Instead of allocating a new temporary each time one
is needed, keep a list of temporaries which are free
(have already been VARKILLed on every path) and use
one of them.
Should save a lot of stack space. In a function like this:
func main() {
fmt.Printf("%d %d\n", 2, 3)
fmt.Printf("%d %d\n", 4, 5)
fmt.Printf("%d %d\n", 6, 7)
}
The three [2]interface{} arrays used to hold the ... args
all use the same autotmp, instead of 3 different autotmps
as happened previous to this CL.
Change-Id: I2d728e226f81e05ae68ca8247af62014a1b032d3
Reviewed-on: https://go-review.googlesource.com/c/140301
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
When we pass these types by reference, we usually have to allocate
temporaries on the stack, initialize them, then pass their address
to the conversion functions. It's simpler to pass these types
directly by value.
This particularly applies to conversions needed for fmt.Printf
(to interface{} for constructing a [...]interface{}).
func f(a, b, c string) {
fmt.Printf("%s %s\n", a, b)
fmt.Printf("%s %s\n", b, c)
}
This function's stack frame shrinks from 200 to 136 bytes, and
its code shrinks from 535 to 453 bytes.
The go binary shrinks 0.3%.
Update #24286
Aside: for this function f, we don't really need to allocate
temporaries for the convT2E function. We could use the address
of a, b, and c directly. That might get similar (or maybe better?)
improvements. I investigated a bit, but it seemed complicated
to do it safely. This change was much easier.
Change-Id: I78cbe51b501fb41e1e324ce4203f0de56a1db82d
Reviewed-on: https://go-review.googlesource.com/c/135377
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Instead of
MOVB go.string."foo"(SB), AX
do
MOVB $102, AX
When we know the global we're loading from is readonly, we can
do that read at compile time.
I've made this arch-dependent mostly because the cases where this
happens often are memory->memory moves, and those don't get
decomposed until lowering.
Did amd64/386/arm/arm64. Other architectures could follow.
Update #26498
Change-Id: I41b1dc831b2cd0a52dac9b97f4f4457888a46389
Reviewed-on: https://go-review.googlesource.com/c/141118
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Do []byte(string) conversions more efficiently when the string
is a constant. Instead of calling stringtobyteslice, allocate
just the space we need and encode the initialization directly.
[]byte("foo") rewrites to the following pseudocode:
var s [3]byte // on heap or stack, depending on whether b escapes
s = *(*[3]byte)(&"foo"[0]) // initialize s from the string
b = s[:]
which generates this assembly:
0x001d 00029 (tmp1.go:9) LEAQ type.[3]uint8(SB), AX
0x0024 00036 (tmp1.go:9) MOVQ AX, (SP)
0x0028 00040 (tmp1.go:9) CALL runtime.newobject(SB)
0x002d 00045 (tmp1.go:9) MOVQ 8(SP), AX
0x0032 00050 (tmp1.go:9) MOVBLZX go.string."foo"+2(SB), CX
0x0039 00057 (tmp1.go:9) MOVWLZX go.string."foo"(SB), DX
0x0040 00064 (tmp1.go:9) MOVW DX, (AX)
0x0043 00067 (tmp1.go:9) MOVB CL, 2(AX)
// Then the slice is b = {AX, 3, 3}
The generated code is still not optimal, as it still does load/store
from read-only memory instead of constant stores. Next CL...
Update #26498Fixes#10170
Change-Id: I4b990b19f9a308f60c8f4f148934acffefe0a5bd
Reviewed-on: https://go-review.googlesource.com/c/140698
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This was missed as part of adding a top-level VARDEF
for stack tracing (CL 134156).
Fixes#28055
Change-Id: Id14748dfccb119197d788867d2ec6a3b3c9835cf
Reviewed-on: https://go-review.googlesource.com/c/140304
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alberto Donizetti <alb.donizetti@gmail.com>
Allocate a long linked list on the stack. This tests both
lots of live stack objects, and lots of intra-stack pointers
to those objects.
Change-Id: I169e067416455737774851633b1e5367e10e1cf2
Reviewed-on: https://go-review.googlesource.com/c/135296
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
When a function triggers a signal (like a segfault which translates to
a nil pointer exception) during execution, a sigpanic handler is just
below it on the stack. The function itself did not stop at a
safepoint, so we have to figure out what safepoint we should use to
scan its stack frame.
Previously we used the site of the most recent defer to get the live
variables at the signal site. That answer is not quite correct, as
explained in #27518. Instead, use the site of a deferreturn call.
It has all the right variables marked as live (no args, all the return
values, except those that escape to the heap, in which case the
corresponding PAUTOHEAP variables will be live instead).
This CL requires stack objects, so that all the local variables
and args referenced by the deferred closures keep the right variables alive.
Fixes#27518
Change-Id: Id45d8a8666759986c203181090b962e2981e48ca
Reviewed-on: https://go-review.googlesource.com/c/134637
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
The previous CL introduced stack objects. This CL removes the old
ambiguously live liveness analysis. After this CL we're relying
on stack objects exclusively.
Update a bunch of liveness tests to reflect the new world.
Fixes#22350
Change-Id: I739b26e015882231011ce6bc1a7f426049e59f31
Reviewed-on: https://go-review.googlesource.com/c/134156
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
In some optimization rules the type of generated OffPtr was
incorrectly set to the type of the pointee, instead of the
pointer. When the OffPtr value is spilled, this may generate
a spill of the wrong type, e.g. a floating point spill of an
integer (pointer) value. On Wasm, this leads to invalid
bytecode.
Fixes#27961.
Change-Id: I5d464847eb900ed90794105c0013a1a7330756cc
Reviewed-on: https://go-review.googlesource.com/c/139257
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Richard Musiol <neelance@gmail.com>
During a call to a reflect-generated function or method (via
makeFuncStub or methodValueCall), when should we scan the return
values?
When we're starting a reflect call, the space on the stack for the
return values is not initialized yet, as it contains whatever junk was
on the stack of the caller at the time. The return space must not be
scanned during a GC.
When we're finishing a reflect call, the return values are
initialized, and must be scanned during a GC to make sure that any
pointers in the return values are found and their referents retained.
When the GC stack walk comes across a reflect call in progress on the
stack, it needs to know whether to scan the results or not. It doesn't
know the progress of the reflect call, so it can't decide by
itself. The reflect package needs to tell it.
This CL adds another slot in the frame of makeFuncStub and
methodValueCall so we can put a boolean in there which tells the
runtime whether to scan the results or not.
This CL also adds the args length to reflectMethodValue so the
runtime can restrict its scanning to only the args section (not the
results) if the reflect package says the results aren't ready yet.
Do a delicate dance in the reflect package to set the "results are
valid" bit. We need to make sure we set the bit only after we've
copied the results back to the stack. But we must set the bit before
we drop reflect's copy of the results. Otherwise, we might have a
state where (temporarily) no one has a live copy of the results.
That's the state we were observing in issue #27695 before this CL.
The bitmap used by the runtime currently contains only the args.
(Actually, it contains all the bits, but the size is set so we use
only the args portion.) This is safe for early in a reflect call, but
unsafe late in a reflect call. The test issue27695.go demonstrates
this unsafety. We change the bitmap to always include both args
and results, and decide at runtime which portion to use.
issue27695.go only has a test for method calls. Function calls were ok
because there wasn't a safepoint between when reflect dropped its copy
of the return values and when the caller is resumed. This may change
when we introduce safepoints everywhere.
This truncate-to-only-the-args was part of CL 9888 (in 2015). That
part of the CL fixed the problem demonstrated in issue27695b.go but
introduced the problem demonstrated in issue27695.go.
TODO, in another CL: simplify FuncLayout and its test. stack return
value is now identical to frametype.ptrdata + frametype.gcdata.
Fixes#27695
Change-Id: I2d49b34e34a82c6328b34f02610587a291b25c5f
Reviewed-on: https://go-review.googlesource.com/137440
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Also includes a small tweak to test/run.go to allow package names
with Unicode letters (as opposed to just ASCII chars).
Updates #27836
Change-Id: Idbf0bdea24174808cddcb69974dab820eb13e521
Reviewed-on: https://go-review.googlesource.com/138075
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Show a more specifc error message in the form of "%d variables but %v
returns %d values" if an assignment mismatch occurs with a function
or method call on the right.
Fixes#27595
Change-Id: Ibc97d070662b08f150ac22d686059cf224e012ab
Reviewed-on: https://go-review.googlesource.com/135575
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
CL 136855 removed the encoding/binary dependency from the checkbce.go
test by defining a local Uint64 to fix the noopt builder; then a more
general mechanism to skip tests on the noopt builder was introduced in
CL 136898, so we can now restore the binary.Uint64 calls in testbce.
Change-Id: I3efbb41be0bfc446a7e638ce6a593371ead2684f
Reviewed-on: https://go-review.googlesource.com/137056
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Adds a new build tag "gcflags_noopt" that can be used in test/*.go
tests.
Fixes#27833
Change-Id: I4ea0ccd9e9e58c4639de18645fec81eb24a3a929
Reviewed-on: https://go-review.googlesource.com/136898
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
&^ and << have equal precedence. Add some parentheses to make sure
we shift before we andnot.
Fixes#27829
Change-Id: Iba8576201f0f7c52bf9795aaa75d15d8f9a76811
Reviewed-on: https://go-review.googlesource.com/136899
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The existing URL in comment points to an Alioth page which was
deprecated (and not working), so use the new Benchmarks Game URL.
Change-Id: Ifd694382a44a24c44acbed3fe1b17bca6dab998f
Reviewed-on: https://go-review.googlesource.com/136835
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The noopt builder is configured by setting GO_GCFLAGS=-N -l, but the
test/run.go test harness doesn't look at GO_GCFLAGS when processing
"errorcheck" files, it just calls compile:
cmdline := []string{goTool(), "tool", "compile", /* etc */}
This is working as intended, since it makes the tests more robust and
independent from the environment; errorcheck files are supposed to set
additional building flags, when needed, like in:
// errorcheck -0 -N -l
The test/bcecheck.go test used to work on the noopt builder (even if
bce is not active on -N -l) because the test was auto-contained and
the file always compiled with optimizations enabled.
In CL 107355, a new bce test dependent on an external package
(encoding.binary) was added. On the noopt builder the external package
is built using -N -l, and this causes a test failure that broke the
noopt builder:
https://build.golang.org/log/b2be319536285e5807ee9d66d6d0ec4d57433768
To reproduce the failure, one can do:
$ go install -a -gcflags="-N -l" std
$ go run run.go -- checkbce.go
This change fixes the noopt builder breakage by removing the bce test
dependency on encoding/binary by defining a local Uint64() function to
be used in the test.
Change-Id: Ife71aab662001442e715c32a0b7d758349a63ff1
Reviewed-on: https://go-review.googlesource.com/136855
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
See the change and comment in typecheck.go for a detailed explanation.
Fixes#26855.
Change-Id: I7867f948490fc0873b1bd849048cda6acbc36e76
Reviewed-on: https://go-review.googlesource.com/136395
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Teach samesafeexpr to handle arithmetic unary and binary ops.
It makes map lookup optimization possible in
m[k+1] = append(m[k+1], ...)
m[-k] = append(m[-k], ...)
... etc
Does not cover "+" for strings (concatenation).
Change-Id: Ibbb16ac3faf176958da344be1471b06d7cf33a6c
Reviewed-on: https://go-review.googlesource.com/135795
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
That optimization is not valid if x == -0.
The test is a bit tricky because 0 == -0. We distinguish
0 from -0 with 1/0 == inf, 1/-0 == -inf.
This has been a bug since CL 24790 in Go 1.8. Probably doesn't
warrant a backport.
Fixes#27718
Note: the optimization x-0 -> x is actually valid.
But it's probably best to take it out, so as to not confuse readers.
Change-Id: I99f16a93b45f7406ec8053c2dc759a13eba035fa
Reviewed-on: https://go-review.googlesource.com/135701
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Instead of skipping all OSLICEARR, skip only ones with non-pointer
array type. For pointers to arrays, it's safe to apply the
self-assignment slicing optimizations.
Refactored the matching code into separate function for readability.
This is an extension to already existing optimization.
On its own, it does not improve any code under std, but
it opens some new optimization opportunities. One
of them is described in the referenced issue.
Updates #7921
Change-Id: I08ac660d3ef80eb15fd7933fb73cf53ded9333ad
Reviewed-on: https://go-review.googlesource.com/133375
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Makes go binary smaller by 0.2%.
I noticed this in autogenerated equal methods, and there are
probably a lot of those.
Change-Id: I4e04eb3653fbceb9dd6a4eee97ceab1fa4d10b72
Reviewed-on: https://go-review.googlesource.com/135379
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
This adds some improvements to the rules for PPC64 to eliminate
unnecessary zero or sign extends, and fix some rule for truncates
which were not always using the correct sign instruction.
This reduces of size of many functions by 1 or 2 instructions and
can improve performance in cases where the execution time depends
on small loops where at least 1 instruction was removed and where that
loop contributes a significant amount of the total execution time.
Included is a testcase for codegen to verify the sign/zero extend
instructions are omitted.
An example of the improvement (strings):
IndexAnyASCII/256:1-16 392ns ± 0% 369ns ± 0% -5.79% (p=0.000 n=1+10)
IndexAnyASCII/256:2-16 397ns ± 0% 376ns ± 0% -5.23% (p=0.000 n=1+9)
IndexAnyASCII/256:4-16 405ns ± 0% 384ns ± 0% -5.19% (p=1.714 n=1+6)
IndexAnyASCII/256:8-16 427ns ± 0% 403ns ± 0% -5.57% (p=0.000 n=1+10)
IndexAnyASCII/256:16-16 441ns ± 0% 418ns ± 1% -5.33% (p=0.000 n=1+10)
IndexAnyASCII/4096:1-16 5.62µs ± 0% 5.27µs ± 1% -6.31% (p=0.000 n=1+10)
IndexAnyASCII/4096:2-16 5.67µs ± 0% 5.29µs ± 0% -6.67% (p=0.222 n=1+8)
IndexAnyASCII/4096:4-16 5.66µs ± 0% 5.28µs ± 1% -6.66% (p=0.000 n=1+10)
IndexAnyASCII/4096:8-16 5.66µs ± 0% 5.31µs ± 1% -6.10% (p=0.000 n=1+10)
IndexAnyASCII/4096:16-16 5.70µs ± 0% 5.33µs ± 1% -6.43% (p=0.182 n=1+10)
Change-Id: I739a6132b505936d39001aada5a978ff2a5f0500
Reviewed-on: https://go-review.googlesource.com/129875
Reviewed-by: David Chase <drchase@google.com>
math.RoundToEven can be done by one arm64 instruction FRINTND, intrinsify it to improve performance.
The current pure Go implementation of the function Abs is translated into five instructions on arm64:
str, ldr, and, str, ldr. The intrinsic implementation requires only one instruction, so in terms of
performance, intrinsify it is worthwhile.
Benchmarks:
name old time/op new time/op delta
Abs-8 3.50ns ± 0% 1.50ns ± 0% -57.14% (p=0.000 n=10+10)
RoundToEven-8 9.26ns ± 0% 1.50ns ± 0% -83.80% (p=0.000 n=10+10)
Change-Id: I9456b26ab282b544dfac0154fc86f17aed96ac3d
Reviewed-on: https://go-review.googlesource.com/116535
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The CL 132915 added the wrong codegen test for math.Copysign(c, -1),
it should test that AND is not emitted. This CL fixes this error.
Change-Id: Ida1d3d54ebfc7f238abccbc1f70f914e1b5bfd91
Reviewed-on: https://go-review.googlesource.com/134815
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Added some more cases that should be guarded against regression.
Change-Id: I9f1dda2fd0be9b6e167ef1cc018fc8cce55c066c
Reviewed-on: https://go-review.googlesource.com/134017
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Add some rules to match the Go code like:
y &= 63
x << y | x >> (64-y)
or
y &= 63
x >> y | x << (64-y)
as a ROR instruction. Make math/bits.RotateLeft faster on arm64.
Extends CL 132435 to arm64.
Benchmarks of math/bits.RotateLeftxxN:
name old time/op new time/op delta
RotateLeft-8 3.548750ns +- 1% 2.003750ns +- 0% -43.54% (p=0.000 n=8+8)
RotateLeft8-8 3.925000ns +- 0% 3.925000ns +- 0% ~ (p=1.000 n=8+8)
RotateLeft16-8 3.925000ns +- 0% 3.927500ns +- 0% ~ (p=0.608 n=8+8)
RotateLeft32-8 3.925000ns +- 0% 2.002500ns +- 0% -48.98% (p=0.000 n=8+8)
RotateLeft64-8 3.536250ns +- 0% 2.003750ns +- 0% -43.34% (p=0.000 n=8+8)
Change-Id: I77622cd7f39b917427e060647321f5513973232c
Reviewed-on: https://go-review.googlesource.com/122542
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Rationale: small buffer optimization does not work and it has
made things slower since 2014. Until we can make it work,
we should prefer simpler code that also turns out to be more
efficient.
With this change, it's possible to use
NewBuffer(make([]byte, 0, bootstrapSize)) to get the desired
stack-allocated initial buffer since escape analysis can
prove the created slice to be non-escaping.
New implementation key points:
- Zero value bytes.Buffer performs better than before
- You can have a truly stack-allocated buffer, and it's not even limited to 64 bytes
- The unsafe.Sizeof(bytes.Buffer{}) is reduced significantly
- Empty writes don't cause allocations
Buffer benchmarks from bytes package:
name old time/op new time/op delta
ReadString-8 9.20µs ± 1% 9.22µs ± 1% ~ (p=0.148 n=10+10)
WriteByte-8 28.1µs ± 0% 26.2µs ± 0% -6.78% (p=0.000 n=10+10)
WriteRune-8 64.9µs ± 0% 65.0µs ± 0% +0.16% (p=0.000 n=10+10)
BufferNotEmptyWriteRead-8 469µs ± 0% 461µs ± 0% -1.76% (p=0.000 n=9+10)
BufferFullSmallReads-8 108µs ± 0% 108µs ± 0% -0.21% (p=0.000 n=10+10)
name old speed new speed delta
ReadString-8 3.56GB/s ± 1% 3.55GB/s ± 1% ~ (p=0.165 n=10+10)
WriteByte-8 146MB/s ± 0% 156MB/s ± 0% +7.26% (p=0.000 n=9+10)
WriteRune-8 189MB/s ± 0% 189MB/s ± 0% -0.16% (p=0.000 n=10+10)
name old alloc/op new alloc/op delta
ReadString-8 32.8kB ± 0% 32.8kB ± 0% ~ (all equal)
WriteByte-8 0.00B 0.00B ~ (all equal)
WriteRune-8 0.00B 0.00B ~ (all equal)
BufferNotEmptyWriteRead-8 4.72kB ± 0% 4.67kB ± 0% -1.02% (p=0.000 n=10+10)
BufferFullSmallReads-8 3.44kB ± 0% 3.33kB ± 0% -3.26% (p=0.000 n=10+10)
name old allocs/op new allocs/op delta
ReadString-8 1.00 ± 0% 1.00 ± 0% ~ (all equal)
WriteByte-8 0.00 0.00 ~ (all equal)
WriteRune-8 0.00 0.00 ~ (all equal)
BufferNotEmptyWriteRead-8 3.00 ± 0% 3.00 ± 0% ~ (all equal)
BufferFullSmallReads-8 3.00 ± 0% 2.00 ± 0% -33.33% (p=0.000 n=10+10)
The most notable thing in go1 benchmarks is reduced allocs in HTTPClientServer (-1 alloc):
HTTPClientServer-8 64.0 ± 0% 63.0 ± 0% -1.56% (p=0.000 n=10+10)
For more explanations and benchmarks see the referenced issue.
Updates #7921
Change-Id: Ica0bf85e1b70fb4f5dc4f6a61045e2cf4ef72aa3
Reviewed-on: https://go-review.googlesource.com/133715
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The existing implementation causes a compiler panic if a function parameter shadows a built-in function, and then calling that shadowed name.
Fixes#27356
Change-Id: I1ffb6dc01e63c7f499e5f6f75f77ce2318f35bcd
Reviewed-on: https://go-review.googlesource.com/132876
Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
For OINDEX and other Left+Right nodes, we want the whole
node to be considered as "may affect memory" if either
of Left or Right affect memory. Initial implementation
only considered node as such if both Left and Right were non-safe.
Change-Id: Icfb965a0b4c24d8f83f3722216db068dad2eba95
Reviewed-on: https://go-review.googlesource.com/133275
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
File is compiled with "-l" flag, so go:noinline is redundant.
Change-Id: Ia269f3b9de9466857fc578ba5164613393e82369
Reviewed-on: https://go-review.googlesource.com/133295
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Makes the error message more consistent between OAS and OAS2.
Fixes#26616.
Change-Id: I07ab46c5ef8a37efb2cb557632697f5d1bf789f7
Reviewed-on: https://go-review.googlesource.com/131280
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Removes unnecessary nil-check when referencing offset from an
address. Suggested by Keith Randall in golang/go#27180.
Updates golang/go#27180
Change-Id: I326ed7fda7cfa98b7e4354c811900707fee26021
Reviewed-on: https://go-review.googlesource.com/131735
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Make OAS2 and OAS2FUNC sink locations point to the assignment position,
not the nth LHS position.
Fixes#26987
Change-Id: Ibeb9df2da754da8b6638fe1e49e813f37515c13c
Reviewed-on: https://go-review.googlesource.com/129315
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
This CL implements the math/bits.OnesCount{8,16,32,64} functions
as intrinsics on s390x using the 'population count' (popcnt)
instruction. This instruction was released as the 'population-count'
facility which uses the same facility bit (45) as the
'distinct-operands' facility which is a pre-requisite for Go on
s390x. We can therefore use it without a feature check.
The s390x popcnt instruction treats a 64 bit register as a vector
of 8 bytes, summing the number of ones in each byte individually.
It then writes the results to the corresponding bytes in the
output register. Therefore to implement OnesCount{16,32,64} we
need to sum the individual byte counts using some extra
instructions. To do this efficiently I've added some additional
pseudo operations to the s390x SSA backend.
Unlike other architectures the new instruction sequence is faster
for OnesCount8, so that is implemented using the intrinsic.
name old time/op new time/op delta
OnesCount 3.21ns ± 1% 1.35ns ± 0% -58.00% (p=0.000 n=20+20)
OnesCount8 0.91ns ± 1% 0.81ns ± 0% -11.43% (p=0.000 n=20+20)
OnesCount16 1.51ns ± 3% 1.21ns ± 0% -19.71% (p=0.000 n=20+17)
OnesCount32 1.91ns ± 0% 1.12ns ± 1% -41.60% (p=0.000 n=19+20)
OnesCount64 3.18ns ± 4% 1.35ns ± 0% -57.52% (p=0.000 n=20+20)
Change-Id: Id54f0bd28b6db9a887ad12c0d72fcc168ef9c4e0
Reviewed-on: https://go-review.googlesource.com/114675
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Teach escape analysis to recognize these assignment patterns
as not causing the src to leak:
val.x = val.y
val.x[i] = val.y[j]
val.x1.x2 = val.x1.y2
... etc
Helps to avoid "leaking param" with assignments showed above.
The implementation is based on somewhat similiar xs=xs[a:b]
special case that is ignored by the escape analysis.
We may figure out more generalized version of this,
but this one looks like a safe step into that direction.
Updates #14858
Change-Id: I6fe5bfedec9c03bdc1d7624883324a523bd11fde
Reviewed-on: https://go-review.googlesource.com/126395
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
This is still not fixed, the testcase reflects that there are still
a few boundchecks. Let's fix the good alternative with an explicit
test though.
Updates #24876
Change-Id: I4da35eb353e19052bd7b69ea6190a69ced8b9b3d
Reviewed-on: https://go-review.googlesource.com/107355
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The codegen testsuite uses regexp to parse the syntax, but it doesn't
have a way to tell line comments containing checks from line comments
containing English sentences. This means that any syntax error (that
is, non-matching regexp) is currently ignored and not reported.
There were some tests in memcombine.go that had an extraneous space
and were thus effectively disabled. It would be great if we could
report it as a syntax error, but for now we just punt and swallow the
spaces as a workaround, to avoid the same mistake again.
Fixes#25452
Change-Id: Ic7747a2278bc00adffd0c199ce40937acbbc9cf0
Reviewed-on: https://go-review.googlesource.com/113835
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Fence-post implications of the form "x-1 >= w && x > min ⇒ x > w"
were not correctly handling unsigned domain, by always checking signed
limits.
This bug was uncovered once we taught prove that len(x) is always
>= 0 in the signed domain.
In the code being miscompiled (s[len(s)-1]), prove checks
whether len(s)-1 >= len(s) in the unsigned domain; if it proves
that this is always false, it can remove the bound check.
Notice that len(s)-1 >= len(s) can be true for len(s) = 0 because
of the wrap-around, so this is something prove should not be
able to deduce.
But because of the bug, the gate condition for the fence-post
implication was len(s) > MinInt64 instead of len(s) > 0; that
condition would be good in the signed domain but not in the
unsigned domain. And since in CL105635 we taught prove that
len(s) >= 0, the condition incorrectly triggered
(len(s) >= 0 > MinInt64) and things were going downfall.
Fixes#27251Fixes#27289
Change-Id: I3dbcb1955ac5a66a0dcbee500f41e8d219409be5
Reviewed-on: https://go-review.googlesource.com/132495
Reviewed-by: Keith Randall <khr@golang.org>
Previously, pattern matching was good enough to achieve good performance
for the RotateLeft* functions, but the inlining cost for them was much
too high. Make RotateLeft* intrinsic on amd64 as a stop-gap for now to
reduce inlining costs.
This should be done (or at least looked at) for other architectures
as well.
Updates golang/go#17566
Change-Id: I6a106ff00b6c4e3f490650af3e083ed2be00c819
Reviewed-on: https://go-review.googlesource.com/132435
Run-TryBot: Andrew Bonventre <andybons@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Nil check is special in that it has no use but we must keep it.
Count it as a use of the auto.
Fixes#27278.
Change-Id: I857c3d0db2ebdca1bc342b4993c0dac5c01e067f
Reviewed-on: https://go-review.googlesource.com/131955
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
This fixes the unwanted behaviour where printing a zero float with the
#v fmt verb outputs "0" - e.g. missing the trailing decimal. This means
that the output would be interpreted as an int rather than a float when
parsed as Go source. After this change the the output is "0.0".
Fixes#26363
Change-Id: Ic5c060522459cd5ce077675d47c848b22ddc34fa
GitHub-Last-Rev: adfb061363
GitHub-Pull-Request: golang/go#26383
Reviewed-on: https://go-review.googlesource.com/123956
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Rob Pike <r@golang.org>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
In the compiler frontend, walkinrange indiscriminately calls Int64()
on const CTINT nodes, even though Int64's return value is undefined
for anything over 2⁶³ (in practise, it'll return a negative number).
This causes the introduction of bad constants during rewrites of
unsigned expressions, which make the compiler reject valid Go
programs.
This change introduces a preliminary check that Int64() is safe to
call on the consts on hand. If it isn't, walkinrange exits without
doing any rewrite.
Fixes#27143
Change-Id: I2017073cae65468a521ff3262d4ea8ab0d7098d9
Reviewed-on: https://go-review.googlesource.com/130735
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Tests in test/safe were neglected after moving to the run.go
framework. This change restores them.
These tests are skipped for go/types via -+ option.
Fixes#25668
Change-Id: I8fe26574a76fa7afa8664c467d7c2e6334f1bba9
Reviewed-on: https://go-review.googlesource.com/124660
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Consolidate decision about whether -race and -msan options are
supported in cmd/internal/sys. Use consolidated functions in
cmd/compile and cmd/go. Use a copy of them in cmd/dist; cmd/dist can't
import cmd/internal/sys because Go 1.4 doesn't have it.
Fixes#24315
Change-Id: I9cecaed4895eb1a2a49379b4848db40de66d32a9
Reviewed-on: https://go-review.googlesource.com/121816
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
We generate MOVBLZX for byte-sized LoadReg, so
(MOVBQZX (LoadReg (Arg))) is the same as
(LoadReg (Arg)). Remove those zero extension where possible.
Triggers several times during all.bash.
Fixes#25378
Updates #15300
Change-Id: If50656e66f217832a13ee8f49c47997f4fcc093a
Reviewed-on: https://go-review.googlesource.com/115617
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Memmove can use AVX/prefetches/other optional instructions, so
only do it for small sizes, when call overhead dominates.
Change-Id: Ice5e93deb11462217f7fb5fc350b703109bb4090
Reviewed-on: https://go-review.googlesource.com/112517
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Munday <mike.munday@ibm.com>
This commit adds an explicit nil check for closure calls on wasm,
so calling a nil func causes a proper panic instead of crashing on the
WebAssembly level.
Change-Id: I6246844f316677976cdd420618be5664444c25ae
Reviewed-on: https://go-review.googlesource.com/127759
Run-TryBot: Richard Musiol <neelance@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Some combined store optimization was already implemented
in go-1.11, but there is no corresponding test cases.
Change-Id: Iebdad186e92047942e53a74f2c20b390922e1e9c
Reviewed-on: https://go-review.googlesource.com/122915
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
If we're compiling a large function, be more picky about how big
the function we're inlining is. If the function is >5000 nodes,
we lower the inlining threshold from a cost of 80 to 20.
Turns out reflect.Value's cost is exactly 80. That's the function
at issue in #26546.
20 was chosen as a proxy for "inlined body is smaller than the call would be".
Simple functions still get inlined, like this one at cost 7:
func ifaceIndir(t *rtype) bool {
return t.kind&kindDirectIface == 0
}
5000 nodes was chosen as the big function size. Here are all the
5000+ node (~~1000+ lines) functions in the stdlib:
5187 cmd/internal/obj/arm (*ctxt5).asmout
6879 cmd/internal/obj/s390x (*ctxtz).asmout
6567 cmd/internal/obj/ppc64 (*ctxt9).asmout
9643 cmd/internal/obj/arm64 (*ctxt7).asmout
5042 cmd/internal/obj/x86 (*AsmBuf).doasm
8768 cmd/compile/internal/ssa rewriteBlockAMD64
8878 cmd/compile/internal/ssa rewriteBlockARM
8344 cmd/compile/internal/ssa rewriteValueARM64_OpARM64OR_20
7916 cmd/compile/internal/ssa rewriteValueARM64_OpARM64OR_30
5427 cmd/compile/internal/ssa rewriteBlockARM64
5126 cmd/compile/internal/ssa rewriteValuePPC64_OpPPC64OR_50
6152 cmd/compile/internal/ssa rewriteValuePPC64_OpPPC64OR_60
6412 cmd/compile/internal/ssa rewriteValuePPC64_OpPPC64OR_70
6486 cmd/compile/internal/ssa rewriteValuePPC64_OpPPC64OR_80
6534 cmd/compile/internal/ssa rewriteValuePPC64_OpPPC64OR_90
6534 cmd/compile/internal/ssa rewriteValuePPC64_OpPPC64OR_100
6534 cmd/compile/internal/ssa rewriteValuePPC64_OpPPC64OR_110
6675 cmd/compile/internal/gc typecheck1
5433 cmd/compile/internal/gc walkexpr
14070 cmd/vendor/golang.org/x/arch/arm64/arm64asm decodeArg
There are a lot more smaller (~1000 node) functions in the stdlib.
The function in #26546 has 12477 nodes.
At some point it might be nice to have a better heuristic for "inlined
body is smaller than the call", a non-cliff way to scale down the cost
as the function gets bigger, doing cheaper inlined calls first, etc.
All that can wait for another release. I'd like to do this CL for
1.11.
Fixes#26546
Update #17566
Change-Id: Idda13020e46ec2b28d79a17217f44b189f8139ac
Reviewed-on: https://go-review.googlesource.com/125516
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Gccgo produced incorrect order of evaluation for expressions
involving &&, || subexpressions. The fix is CL 125299.
Updates #26495.
Change-Id: I18d873281709f3160b3e09f0b2e46f5c120e1cab
Reviewed-on: https://go-review.googlesource.com/125301
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Code fix was in CL 122556. This is a corresponding test case.
Fixes#26426
Change-Id: Ib8769f367aed8bead029da0a8d2ddccee1d1dccb
Reviewed-on: https://go-review.googlesource.com/124535
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
If one tries to use promoted fields in a struct literal, the compiler
errors correctly. However, if the embedded fields are of struct pointer
type, the field.Type.Sym.Name expression below panics.
This is because field.Type.Sym is nil in that case. We can simply use
field.Sym.Name in this piece of code though, as it only concerns
embedded fields, in which case what we are after is the field name.
Added a test mirroring fixedbugs/issue23609.go, but with pointer types.
Fixes#26416.
Change-Id: Ia46ce62995c9e1653f315accb99d592aff2f285e
Reviewed-on: https://go-review.googlesource.com/124395
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
The arm64 backend generates "TST" for "if uint32(a)&uint32(b) == 0",
which should be "TSTW".
fixes#26438
Change-Id: I7d64c30e3a840b43486bcd10eea2e3e75aaa4857
Reviewed-on: https://go-review.googlesource.com/124637
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Autos must be kept if their address reaches the control value of a
block. We didn't see this before because it is rare for an auto's
address to reach a control value without also reaching a phi or
being written to memory. We can probably optimize away the
comparisons that lead to this scenario since autos cannot alias
with pointers from elsewhere, however for now we take the
conservative approach and just ensure the auto is properly
initialised if its address reaches a control value.
Fixes#26407.
Change-Id: I02265793f010a9e001c3e1a5397c290c6769d4de
Reviewed-on: https://go-review.googlesource.com/124335
Reviewed-by: David Chase <drchase@google.com>
If both branches of a write barrier test go to the same block,
then there's no unsafe points.
This can only happen if the resulting memory state is somehow dead,
which can only occur in degenerate cases, like infinite loops. No
point in cleaning up the useless branch in these situations.
Fixes#26024.
Change-Id: I93a7df9fdf2fc94c6c4b1fe61180dc4fd4a0871f
Reviewed-on: https://go-review.googlesource.com/123655
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Lack of a well-defined order between VarDef and related
address operations sometimes causes problems with store order
and write barrier transformations; glitches in the order are
made irreparable (by later optimizations) if the two parts of
the glitch straddle a split in the original block caused by
insertion of a write barrier diamond.
Fix this by creating a LocalAddr for addresses of locals
(what VarDef matters for) that takes a memory input to
help make the order explicit. Addr is modified to only
be legal for SB operand, so there is no overlap between
Addr and LocalAddr uses (there may be some downstream
cleanup from this).
Changes to generic.rules and rewrite.go ensure that codegen
tests continue to pass; CSE of LocalAddr is impaired, not
quite sure of the cost.
Fixes#26105.
Change-Id: Id4192b4440aa4e9d7ba54a465c456df9b530b515
Reviewed-on: https://go-review.googlesource.com/122483
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
For golang.org/cl/74110, I forgot that you can use range-based for
loops to extract key values from a map value.
This wasn't a problem for the binary format importer, because it was
more tolerant about missing inline function bodies. However, the
indexed importer is more particular about this.
We could potentially just make it more lenient like the binary
importer, but tweaking the logic here is easy enough and seems like
the preferable solution.
Fixes#26341.
Change-Id: I54564dcd0be60ea393f8a0f6954b7d3d61e96ee5
Reviewed-on: https://go-review.googlesource.com/123475
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Fix the panic message produced for an interface conversion error to
only say "types from different packages" if they are definitely from
different packges. If they may be from the same package, say "types
from different scopes."
Updates #18911Fixes#26094
Change-Id: I0cea50ba31007d88e70c067b4680009ede69bab9
Reviewed-on: https://go-review.googlesource.com/123395
Reviewed-by: Austin Clements <austin@google.com>
Functions exported on behalf of other packages need to have their
argument stack maps specified explicitly. They don't get an implicit
map because they are not in the local package, and if they get defer'd
they need argument maps.
Fixes#24419
Change-Id: I35b7d8b4a03d4770ba88699e1007cb3fcb5397a9
Reviewed-on: https://go-review.googlesource.com/122676
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
More test cases of combined load for arm64.
Change-Id: I7a9f4dcec6930f161cbded1f47dbf7fcef1db4f1
Reviewed-on: https://go-review.googlesource.com/122582
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
When DWARF is disabled, some alg functions were not generated.
Make sure they are generated when we about to generate calls to
them.
Fixes#23546.
Change-Id: Iecfa0eea830e42ee92e55268167cefb1540980b2
Reviewed-on: https://go-review.googlesource.com/122403
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
We need to make sure that the terminating comparison has the right
sense given the increment direction. If the increment is positive,
the terminating comparsion must be < or <=. If the increment is
negative, the terminating comparison must be > or >=.
Do a few cleanups, like constant-folding entry==0, adding comments,
removing unused "exported" fields.
Fixes#26116
Change-Id: I14230ee8126054b750e2a1f2b18eb8f09873dbd5
Reviewed-on: https://go-review.googlesource.com/121940
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Expanding interface method sets is handled during width calculation,
which can't be performed concurrently. Make sure that we eagerly
expand interfaces in the frontend when importing them, even if they're
not actually used by code, because we might need to generate a type
description of them.
Fixes#25055.
Change-Id: I6fd2756de2c7d5dbc33056f70b3028ca3aebab41
Reviewed-on: https://go-review.googlesource.com/122517
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Late opt pass may generate dead stores, which messes up store
chain calculation in later passes. Run generic deadcode even
in -N mode to remove them.
Fixes#26163.
Change-Id: I8276101717bb978d5980e6c7998f53fd8d0ae10f
Reviewed-on: https://go-review.googlesource.com/121856
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
If the address of an auto reaches a phi then any further stores to
the pointer represented by the phi probably need to be kept. This
is because stores to the other arguments to the phi may be visible
to the program.
Fixes#26153.
Change-Id: Ic506c6c543bf70d792e5b1a64bdde1e5fdf1126a
Reviewed-on: https://go-review.googlesource.com/121796
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
This reverts commit 1a27f048ad.
Reason for revert: Broke the ssacheck and -N-l builders, and the -N-l fix looks like it will take some time and take a different route entirely.
Change-Id: Ie0ac5e86ab7d72a303dfbbc48dfdf1e092d4f61a
Reviewed-on: https://go-review.googlesource.com/121715
Reviewed-by: David Chase <drchase@google.com>
Given a carefully constructed input, writebarrier would
split a block with the OpAddr in the first half and the
VarDef in the second half which ultimately leads to a
compiler crash because the scheduler is no longer able
to put them in the proper order.
To fix, recognize the implicit dependence of OpAddr on
the VarDef of the same symbol if any exists.
This fix was chosen over making OpAddr take a memory
operand to make the dependence explicit, because this
change is less invasive at this late part of the 1.11
release cycle.
Fixes#26105.
Change-Id: I9b65460673af3af41740ef877d2fca91acd336bc
Reviewed-on: https://go-review.googlesource.com/121436
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
SSA can handle 1-element array, but only when the element type
is SSAable. When building SSA for INDEX of 1-element array, we
did not check the element type is SSAable. And when it's not,
it resulted in an unhandled SSA op.
Fixes#26120.
Change-Id: Id709996b5d9d90212f6c56d3f27eed320a4d8360
Reviewed-on: https://go-review.googlesource.com/121496
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Code generation for OpAMD64CMOV[WLQ]EQF uses AX as a scratch register,
but only CMOVQEQF, correctly lets compiler know. Mark other 2 as
clobbering AX.
Fixes#26097
Change-Id: I2a65bd67bf18a540898b4a0ae6c8766e0b767b19
Reviewed-on: https://go-review.googlesource.com/121336
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
On Wasm, the offset was not folded into LoweredAddr, so it was
not rematerializeable. This led to the address-taken operation
in some cases generated too early, before the local variable
becoming live. The liveness code thinks the variable live when
the address is taken, then backs it up to live at function
entry, then complains about it, because nothing other than
arguments should be live on entry.
This CL folds the offset into the address operation, so it is
rematerializeable and so generated right before use, after the
variable actually becomes live.
It might be possible to relax the liveness code not to think a
variable live when its address being taken, but until the address
actually being used. But it would be quite complicated. As we're
late in Go 1.11 freeze, it would be better not to do it. Also,
I think the address operation is rematerializeable now on all
architectures, so this is probably less necessary.
This may also be a slight optimization, as the address+offset is
now rematerializeable, which can be generated on the Wasm stack,
without using any "registers" which are emulated by local
variables on Wasm. I don't know how to do benchmarks on Wasm. At
least, cmd/go binary size shrinks 9K.
Fixes#25966.
Change-Id: I01e5869515d6a3942fccdcb857f924a866876e57
Reviewed-on: https://go-review.googlesource.com/120599
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Richard Musiol <neelance@gmail.com>
For non-unit increment, loopbce checks to see if the
increment evenly divides the difference between (constant)
loop start and end. This test panics when the increment
is zero.
Fix: check for zero, if found, don't optimize the loop.
Also added missing copyright notice to loopbce.go.
Fixes#26043.
Change-Id: I5f460104879cacc94481949234c9ce8c519d6380
Reviewed-on: https://go-review.googlesource.com/120759
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
If expanding an inline function body required lazily expanding a
package-scoped type whose identifier was shadowed within the function
body, the lazy expansion would instead overwrite the local symbol
definition instead of the package-scoped symbol. This was due to
importsym using s.Def instead of s.PkgDef.
Unfortunately, this is yet another consequence of the current awkward
scope handling code.
Passes toolstash-check.
Fixes#25984.
Change-Id: Ia7033e1749a883e6e979c854d4b12b0b28083dd8
Reviewed-on: https://go-review.googlesource.com/120456
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
MOVWconst's AuxInt is Int32. SSA check complains if the AuxInt
does not fit in int32. Convert uint32 to int32 to make it happy.
The generated code is unchanged. MOVW only cares low 32 bits.
Passes "toolstash -cmp" std cmd for ARM.
Fixes#25993.
Change-Id: I2b6532c9c285ea6d89652505fb7c553f85a98864
Reviewed-on: https://go-review.googlesource.com/120335
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Adds the appropriate check to inl.go.
Includes tests of both -race+go:norace and plain go:norace.
Fixes#24651.
Change-Id: Id806342430c20baf4679a985d12eea3b677092e0
Reviewed-on: https://go-review.googlesource.com/119195
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Inlining of switch statements into a RETURNed expression
can sometimes lead to the switch being walked twice, which
results in a miscompiled switch statement. The bug depends
on:
1) multiple results
2) named results
3) a return statement whose expression includes a call to a
function containing a switch statement that is inlined.
It may also be significant that the default case of that
switch is a panic(), though that's not proven.
Rearranged the walk case for ORETURN so that double walks are
not possible. Added a test, because this is so fiddly.
Added a check against double walks, verified that it fires
w/o other fix.
Fixes#25776.
Change-Id: I2d594351fa082632512ef989af67eb887059729b
Reviewed-on: https://go-review.googlesource.com/118318
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Ensure that compiler error suggestions after case insensitive
field lookups don't mistakenly reported unexported fields if
those fields aren't in the local package being processed.
Fixes#25727
Change-Id: Icae84388c2a82c8cb539f3d43ad348f50a644caa
Reviewed-on: https://go-review.googlesource.com/117755
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The original fix (https://go-review.googlesource.com/c/go/+/35831)
for this issue was incorrect as it reported cycles in cases where
it shouldn't.
Instead, use a different approach: A type cycle containing aliases
is only a cycle if there are no type definitions. As soon as there
is a type definition, alias expansion terminates and there is no
cycle.
Approach: Split sprint_depchain into two non-recursive and more
easily understandable functions (cycleFor and cycleTrace),
and use those instead for cycle reporting. Analyze the cycle
returned by cycleFor before issueing an alias cycle error.
Also: Removed original fix (main.go) which introduced a separate
crash (#23823).
Fixes#18640.
Fixes#23823.
Fixes#24939.
Change-Id: Ic3707a9dec40a71dc928a3e49b4868c5fac3d3b7
Reviewed-on: https://go-review.googlesource.com/118078
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This line of the inlining tuning experiment
https://go-review.googlesource.com/c/go/+/109918/1/src/cmd/compile/internal/gc/inl.go#347
was incorrectly rewritten in a later patch to use the call
cost, not the panic cost, and thus the inlining of panic
didn't occur when it should. I discovered this when I
realized that tests should have failed, but didn't.
Fix is to make the correct change, and also to modify the
tests that this causes to fail. One test now asserts the
new normal, the other calls "ppanic" instead which is
designed to behave like panic but not be inlined.
Change-Id: I423bb7f08bd66a70d999826dd9b87027abf34cdf
Reviewed-on: https://go-review.googlesource.com/116656
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Every action has a short annotation.
The errorCheck function has a comment adapted from errchk script.
Removed redundant assigments to tmpDir.
Change-Id: Ifdd1284de046a0ce2aad26bd8da8a8e6a7707a8e
Reviewed-on: https://go-review.googlesource.com/115856
Run-TryBot: Yury Smolsky <yury@smolsky.by>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The wasm archtecture was missing a rule to handle OffPtr with a
negative offset. This commit makes it so OffPtr always gets lowered
to I64AddConst.
Fixes#25741
Change-Id: I1d48e2954e3ff31deb8cba9a9bf0cab7c4bab71a
Reviewed-on: https://go-review.googlesource.com/116595
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
In the old binary export format, parameter names for parameter lists
which contained only types where never written, so this problem didn't
come up.
Fixes#25101.
Change-Id: Ia8b817f7f467570b05f88d584e86b6ef4acdccc6
Reviewed-on: https://go-review.googlesource.com/116376
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
The stack frame includes the callee args section. At the point where
we were checking the frame size, that part of the frame had not been
computed yet. Move the check later so we can include the callee args size.
Fixes#20780
Update #25507
Change-Id: Iab97cb89b3a24f8ca19b9123ef2a111d6850c3fe
Reviewed-on: https://go-review.googlesource.com/115195
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Before the CL 115277 we did not run the test on Windows,
so let's just go back to not running the test on Windows.
There is nothing OS-specific about this test,
so skipping it on Windows doesn't seem like a big deal.
Updates #25693Fixes#25586
Change-Id: I1eb3e158b322d73e271ef388f8c6e2f2af0a0729
Reviewed-on: https://go-review.googlesource.com/115857
Run-TryBot: Yury Smolsky <yury@smolsky.by>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This CL removes the rundircmpout action completely
because it is not used anywhere.
The run case already looks for output files. Rename the cmpout action
mentioned in tests to the run action and remove "cmpout" from run.go.
Change-Id: I835ceb70082927f8e9360e0ea0ba74f296363ab3
Reviewed-on: https://go-review.googlesource.com/115575
Run-TryBot: Yury Smolsky <yury@smolsky.by>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
To allow testing of fixedbugs/bug345.go in Go,
a new flag -n is introduced. This flag disables setting
of relative path for local imports and imports search path
to current dir, namely -D . -I . are not passed to the compiler.
Error regexps are fixed to allow running the test in temp directory.
This change eliminates the last place where Perl
script "errchk" was used.
Fixes#25586.
Change-Id: If085f466e6955312d77315f96d3ef1cb68495aef
Reviewed-on: https://go-review.googlesource.com/115277
Run-TryBot: Yury Smolsky <yury@smolsky.by>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
When we deadcode-remove a block which is a write barrier test,
remove that block from the list of write barrier test blocks.
Fixes#25516
Change-Id: I1efe732d5476003eab4ad6bf67d0340d7874ff0c
Reviewed-on: https://go-review.googlesource.com/115037
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Extend stack frame limit of 1GB to include large argument/return areas.
Argument/return areas are part of the parent frame, not the frame itself,
so they need to be handled separately.
Fixes#25507.
Change-Id: I309298a58faee3e7c1dac80bd2f1166c82460087
Reviewed-on: https://go-review.googlesource.com/115036
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This change enables bug248 to be tested with Go code.
For that, it adds a flag -1 to error check and run directory
with one package failing compilation prior the last package
which should be run.
Specifically, the "p" package in bug1.go file was renamed into "q"
to compile them in separate steps,
bug2.go and bug3.go files were reordered,
bug2.go was changed into non-main package.
Updates #25586.
Change-Id: Ie47aacd56ebb2ce4eac66c792d1a53e1e30e637c
Reviewed-on: https://go-review.googlesource.com/114818
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
1. Some incorrect test cases are disabled.
2. Some wrong test cases are corrected.
3. Some new test cases are added.
Change-Id: Ib5d0473d55159f233ddab79f96967eaec7b08597
Reviewed-on: https://go-review.googlesource.com/113736
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This modifies issafepoint in liveness analysis to report almost every
operation as a safe point. There are four things we don't mark as
safe-points:
1. Runtime code (other than at calls).
2. go:nosplit functions (other than at calls).
3. Instructions between the load of the write barrier-enabled flag and
the write.
4. Instructions leading up to a uintptr -> unsafe.Pointer conversion.
We'll optimize this in later CLs:
name old time/op new time/op delta
Template 185ms ± 2% 190ms ± 2% +2.95% (p=0.000 n=10+10)
Unicode 96.3ms ± 3% 96.4ms ± 1% ~ (p=0.905 n=10+9)
GoTypes 658ms ± 0% 669ms ± 1% +1.72% (p=0.000 n=10+9)
Compiler 3.14s ± 1% 3.18s ± 1% +1.56% (p=0.000 n=9+10)
SSA 7.41s ± 2% 7.59s ± 1% +2.48% (p=0.000 n=9+10)
Flate 126ms ± 1% 128ms ± 1% +2.08% (p=0.000 n=10+10)
GoParser 153ms ± 1% 157ms ± 2% +2.38% (p=0.000 n=10+10)
Reflect 437ms ± 1% 442ms ± 1% +0.98% (p=0.001 n=10+10)
Tar 178ms ± 1% 179ms ± 1% +0.67% (p=0.035 n=10+9)
XML 223ms ± 1% 229ms ± 1% +2.58% (p=0.000 n=10+10)
[Geo mean] 394ms 401ms +1.75%
No effect on binary size because we're not yet emitting these extra
safe points.
For #24543.
Change-Id: I16a1eebb9183cad7cef9d53c0fd21a973cad6859
Reviewed-on: https://go-review.googlesource.com/109348
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Currently, range loops over slices and arrays are compiled roughly
like:
for i, x := range s { b }
⇓
for i, _n, _p := 0, len(s), &s[0]; i < _n; i, _p = i+1, _p + unsafe.Sizeof(s[0]) { b }
⇓
i, _n, _p := 0, len(s), &s[0]
goto cond
body:
{ b }
i, _p = i+1, _p + unsafe.Sizeof(s[0])
cond:
if i < _n { goto body } else { goto end }
end:
The problem with this lowering is that _p may temporarily point past
the end of the allocation the moment before the loop terminates. Right
now this isn't a problem because there's never a safe-point during
this brief moment.
We're about to introduce safe-points everywhere, so this bad pointer
is going to be a problem. We could mark the increment as an unsafe
block, but this inhibits reordering opportunities and could result in
infrequent safe-points if the body is short.
Instead, this CL fixes this by changing how we compile range loops to
never produce this past-the-end pointer. It changes the lowering to
roughly:
i, _n, _p := 0, len(s), &s[0]
if i < _n { goto body } else { goto end }
top:
_p += unsafe.Sizeof(s[0])
body:
{ b }
i++
if i < _n { goto top } else { goto end }
end:
Notably, the increment is split into two parts: we increment the index
before checking the condition, but increment the pointer only *after*
the condition check has succeeded.
The implementation builds on the OFORUNTIL construct that was
introduced during the loop preemption experiments, since OFORUNTIL
places the increment and condition after the loop body. To support the
extra "late increment" step, we further define OFORUNTIL's "List"
field to contain the late increment statements. This makes all of this
a relatively small change.
This depends on the improvements to the prove pass in CL 102603. With
the current lowering, bounds-check elimination knows that i < _n in
the body because the body block is dominated by the cond block. In the
new lowering, deriving this fact requires detecting that i < _n on
*both* paths into body and hence is true in body. CL 102603 made prove
able to detect this.
The code size effect of this is minimal. The cmd/go binary on
linux/amd64 increases by 0.17%. Performance-wise, this actually
appears to be a net win, though it's mostly noise:
name old time/op new time/op delta
BinaryTree17-12 2.80s ± 0% 2.61s ± 1% -6.88% (p=0.000 n=20+18)
Fannkuch11-12 2.41s ± 0% 2.42s ± 0% +0.05% (p=0.005 n=20+20)
FmtFprintfEmpty-12 41.6ns ± 5% 41.4ns ± 6% ~ (p=0.765 n=20+19)
FmtFprintfString-12 69.4ns ± 3% 69.3ns ± 1% ~ (p=0.084 n=19+17)
FmtFprintfInt-12 76.1ns ± 1% 77.3ns ± 1% +1.57% (p=0.000 n=19+19)
FmtFprintfIntInt-12 122ns ± 2% 123ns ± 3% +0.95% (p=0.015 n=20+20)
FmtFprintfPrefixedInt-12 153ns ± 2% 151ns ± 3% -1.27% (p=0.013 n=20+20)
FmtFprintfFloat-12 215ns ± 0% 216ns ± 0% +0.47% (p=0.000 n=20+16)
FmtManyArgs-12 486ns ± 1% 498ns ± 0% +2.40% (p=0.000 n=20+17)
GobDecode-12 6.43ms ± 0% 6.50ms ± 0% +1.08% (p=0.000 n=18+19)
GobEncode-12 5.43ms ± 1% 5.47ms ± 0% +0.76% (p=0.000 n=20+20)
Gzip-12 218ms ± 1% 218ms ± 1% ~ (p=0.883 n=20+20)
Gunzip-12 38.8ms ± 0% 38.9ms ± 0% ~ (p=0.644 n=19+19)
HTTPClientServer-12 76.2µs ± 1% 76.4µs ± 2% ~ (p=0.218 n=20+20)
JSONEncode-12 12.2ms ± 0% 12.3ms ± 1% +0.45% (p=0.000 n=19+19)
JSONDecode-12 54.2ms ± 1% 53.3ms ± 0% -1.67% (p=0.000 n=20+20)
Mandelbrot200-12 3.71ms ± 0% 3.71ms ± 0% ~ (p=0.143 n=19+20)
GoParse-12 3.22ms ± 0% 3.19ms ± 1% -0.72% (p=0.000 n=20+20)
RegexpMatchEasy0_32-12 76.7ns ± 1% 75.8ns ± 1% -1.19% (p=0.000 n=20+17)
RegexpMatchEasy0_1K-12 245ns ± 1% 243ns ± 0% -0.72% (p=0.000 n=18+17)
RegexpMatchEasy1_32-12 71.9ns ± 0% 71.7ns ± 1% -0.39% (p=0.006 n=12+18)
RegexpMatchEasy1_1K-12 358ns ± 1% 354ns ± 1% -1.13% (p=0.000 n=20+19)
RegexpMatchMedium_32-12 105ns ± 2% 105ns ± 1% -0.63% (p=0.007 n=19+20)
RegexpMatchMedium_1K-12 31.9µs ± 1% 31.9µs ± 1% ~ (p=1.000 n=17+17)
RegexpMatchHard_32-12 1.51µs ± 1% 1.52µs ± 2% +0.46% (p=0.042 n=18+18)
RegexpMatchHard_1K-12 45.3µs ± 1% 45.5µs ± 2% +0.44% (p=0.029 n=18+19)
Revcomp-12 388ms ± 1% 385ms ± 0% -0.57% (p=0.000 n=19+18)
Template-12 63.0ms ± 1% 63.3ms ± 0% +0.50% (p=0.000 n=19+20)
TimeParse-12 309ns ± 1% 307ns ± 0% -0.62% (p=0.000 n=20+20)
TimeFormat-12 328ns ± 0% 333ns ± 0% +1.35% (p=0.000 n=19+19)
[Geo mean] 47.0µs 46.9µs -0.20%
(https://perf.golang.org/search?q=upload:20180326.1)
For #10958.
For #24543.
Change-Id: Icbd52e711fdbe7938a1fea3e6baca1104b53ac3a
Reviewed-on: https://go-review.googlesource.com/102604
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Currently, we compile range loops into for loops with the obvious
initialization and update of the index variable. In this form, the
prove pass can see that the body is dominated by an i < len condition,
and findIndVar can detect that i is an induction variable and that
0 <= i < len.
GOEXPERIMENT=preemptibleloops compiles range loops to OFORUNTIL and
we're preparing to unconditionally switch to a variation of this for
#24543. OFORUNTIL moves the increment and condition *after* the body,
which makes the bounds on the index variable much less obvious. With
OFORUNTIL, proving anything about the index variable requires
understanding the phi that joins the index values at the top of the
loop body block.
This interferes with both prove's ability to see that i < len (this is
true on both paths that enter the body, but from two different
conditional checks) and with findIndVar's ability to detect the
induction pattern.
Fix this by teaching prove to detect that the index in the pattern
constructed by OFORUNTIL is an induction variable and add both bounds
to the facts table. Currently this is done separately from findIndVar
because it depends on prove's factsTable, while findIndVar runs before
visiting blocks and building the factsTable.
Without any GOEXPERIMENT, this has no effect on std or cmd. However,
with GOEXPERIMENT=preemptibleloops, this change becomes necessary to
prove 90 conditions in std and cmd.
Change-Id: Ic025d669f81b53426309da5a6e8010e5ccaf4f49
Reviewed-on: https://go-review.googlesource.com/102603
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
This test measures "line churn" which was minimized to help
improve the debugger experience. With proper is_stmt markers,
this is no longer necessary, and it is more accurate (for
profiling) to allow line numbers to vary willy-nilly.
"Debugger experience" is now better measured by
cmd/compile/internal/ssa/debug_test.go
This CL made the obsoleting change:
https://go-review.googlesource.com/c/go/+/102435
Change-Id: I874ab89f3b243b905aaeba7836118f632225a667
Reviewed-on: https://go-review.googlesource.com/113155
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
A new pass run after ssa building (before any other
optimization) identifies the "first" ssa node for each
statement. Other "noise" nodes are tagged as being never
appropriate for a statement boundary (e.g., VarKill, VarDef,
Phi).
Rewrite, deadcode, cse, and nilcheck are modified to move
the statement boundaries forward whenever possible if a
boundary-tagged ssa value is removed; never-boundary nodes
are ignored in this search (some operations involving
constants are also tagged as never-boundary and also ignored
because they are likely to be moved or removed during
optimization).
Code generation treats all nodes except those explicitly
marked as statement boundaries as "not statement" nodes,
and floats statement boundaries to the beginning of each
same-line run of instructions found within a basic block.
Line number html conversion was modified to make statement
boundary nodes a bit more obvious by prepending a "+".
The code in fuse.go that glued together the value slices
of two blocks produced a result that depended on the
former capacities (not lengths) of the two slices. This
causes differences in the 386 bootstrap, and also can
sometimes put values into an order that does a worse job
of preserving statement boundaries when values are removed.
Portions of two delve tests that had caught problems were
incorporated into ssa/debug_test.go. There are some
opportunities to do better with optimized code, but the
next-ing is not lying or overly jumpy.
Over 4 CLs, compilebench geomean measured binary size
increase of 3.5% and compile user time increase of 3.8%
(this is after optimization to reuse a sparse map instead
of creating multiple maps.)
This CL worsens the optimized-debugging experience with
Delve; we need to work with the delve team so that
they can use the is_stmt marks that we're emitting now.
The reference output changes from time to time depending
on other changes in the compiler, sometimes better,
sometimes worse.
This CL now includes a test ensuring that 99+% of the lines
in the Go command itself (a handy optimized binary) include
is_stmt markers.
Change-Id: I359c94e06843f1eb41f9da437bd614885aa9644a
Reviewed-on: https://go-review.googlesource.com/102435
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Don't do direct loads from argument slots if the sizes don't match.
This prevents us from loading from a float32 using a uint64 load
during expressions like uint64(math.float32Bits(f)) where f is a float32 arg.
Fixes#25322
Change-Id: I3887d76f78c844ba546243e7721d811c3d4a9700
Reviewed-on: https://go-review.googlesource.com/112637
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Initialization of t.UInt is missing from SetTypPtrs in config.go,
preventing rules that use it from matching when they should.
This adds the initialization to allow those rules to work.
Updated test/codegen/rotate.go to test for this case, which
appears in math/bits RotateLeft32 and RotateLeft64. There had been
a testcase for this in go 1.10 but that went away when asm_test.go
was removed.
Change-Id: I82fc825ad8364df6fc36a69a1e448214d2e24ed5
Reviewed-on: https://go-review.googlesource.com/112518
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Move ops can be faster than memmove calls because the number of bytes
to be moved is fixed and they don't incur the overhead of a call.
This change allows memmove to be converted into a Move op when the
arguments are disjoint.
The optimization is only enabled on s390x at the moment, however
other architectures may also benefit from it in the future. The
memmove inlining rule triggers an extra 12 times when compiling the
standard library. It will most likely make more of a difference as the
disjoint function is improved over time (to recognize fresh heap
allocations for example).
Change-Id: I9af570dcfff28257b8e59e0ff584a46d8e248310
Reviewed-on: https://go-review.googlesource.com/110064
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
This test runs independent goroutines modifying a comprehensive variety
of local vars to look for garbage collector regressions. This test has
been verified to trigger issue 22781 on the go1.9.2 tag. This test
expands on test/fixedbugs/issue22781.go.
Tests #22781
Change-Id: Id32f8dde7ef650aea1b1b4cf518e6d045537bfdc
Reviewed-on: https://go-review.googlesource.com/93715
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
replace map clears of the form:
for k := range m {
delete(m, k)
}
(where m is map with key type that is reflexive for ==)
with a new runtime function that clears the maps backing
array with a memclr and reinitializes the hmap struct.
Map key types that for example contain floats are not
replaced by this optimization since NaN keys cannot
be deleted from maps using delete.
name old time/op new time/op delta
GoMapClear/Reflexive/1 92.2ns ± 1% 47.1ns ± 2% -48.89% (p=0.000 n=9+9)
GoMapClear/Reflexive/10 108ns ± 1% 48ns ± 2% -55.68% (p=0.000 n=10+10)
GoMapClear/Reflexive/100 303ns ± 2% 110ns ± 3% -63.56% (p=0.000 n=10+10)
GoMapClear/Reflexive/1000 3.58µs ± 3% 1.23µs ± 2% -65.49% (p=0.000 n=9+10)
GoMapClear/Reflexive/10000 28.2µs ± 3% 10.3µs ± 2% -63.55% (p=0.000 n=9+10)
GoMapClear/NonReflexive/1 121ns ± 2% 124ns ± 7% ~ (p=0.097 n=10+10)
GoMapClear/NonReflexive/10 137ns ± 2% 139ns ± 3% +1.53% (p=0.033 n=10+10)
GoMapClear/NonReflexive/100 331ns ± 3% 334ns ± 2% ~ (p=0.342 n=10+10)
GoMapClear/NonReflexive/1000 3.64µs ± 3% 3.64µs ± 2% ~ (p=0.887 n=9+10)
GoMapClear/NonReflexive/10000 28.1µs ± 2% 28.4µs ± 3% ~ (p=0.247 n=10+10)
Fixes#20138
Change-Id: I181332a8ef434a4f0d89659f492d8711db3f3213
Reviewed-on: https://go-review.googlesource.com/110055
Reviewed-by: Keith Randall <khr@golang.org>
Use conditional moves instead of subtractions with borrow to handle
saturation cases. This allows us to delete the SUBE/SUBEW ops and
associated rules from the SSA backend. Using conditional moves also
means we can detect when shift values are masked so I've added some
new rules to constant fold the relevant comparisons and masking ops.
Also use the new shiftIsBounded() function to avoid generating code
to handle saturation cases where possible.
Updates #25167 for s390x.
Change-Id: Ief9991c91267c9151ce4c5ec07642abb4dcc1c0d
Reviewed-on: https://go-review.googlesource.com/110070
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Rename memclrrange to signify that it does not handle
all types of range clears.
Simplify checks to detect the range clear idiom for
arrays and slices.
Add tests to verify the optimization for the slice
range clear idiom is being applied by the compiler.
Change-Id: I5c3b7c9a479699ebdb4c407fde692f30f377860c
Reviewed-on: https://go-review.googlesource.com/110477
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Now the registration phase looks like:
var cases [4]runtime.scases
var order [8]uint16
selectsend(&cases[0], c1, &v1)
selectrecv(&cases[1], c2, &v2, nil)
selectrecv(&cases[2], c3, &v3, &ok)
selectdefault(&cases[3])
chosen := selectgo(&cases[0], &order[0], 4)
Primarily, this is just preparation for having the compiler open-code
selectsend, selectrecv, and selectdefault.
As a minor benefit, order can now be layed out separately on the stack
in the pointer-free segment, so it won't take up space in the
function's stack pointer maps.
Change-Id: I5552ba594201efd31fcb40084da20b42ea569a45
Reviewed-on: https://go-review.googlesource.com/37933
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
The general policy for the current state of js/wasm is that it only
has to support tests that are also supported by nacl.
The test nilptr3.go makes assumptions about which nil checks can be
removed. Since WebAssembly does not signal on reading a null pointer,
all nil checks have to be explicit.
Updates #18892
Change-Id: I06a687860b8d22ae26b1c391499c0f5183e4c485
Reviewed-on: https://go-review.googlesource.com/110096
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
When a loop has bound len(s)-delta, findIndVar detected it and
returned len(s) as (conservative) upper bound. This little lie
allowed loopbce to drop bound checks.
It is obviously more generic to teach prove about relations like
x+d<w for non-constant "w"; we already handled the case for
constant "w", so we just want to learn that if d<0, then x+d<w
proves that x<w.
To be able to remove the code from findIndVar, we also need
to teach prove that len() and cap() are always non-negative.
This CL allows to prove 633 more checks in cmd+std. Most
of them are cases where the code was already testing before
accessing a slice but the compiler didn't know it. For instance,
take strings.HasSuffix:
func HasSuffix(s, suffix string) bool {
return len(s) >= len(suffix) && s[len(s)-len(suffix):] == suffix
}
When suffix is a literal string, the compiler now understands
that the explicit check is enough to not emit a slice check.
I also found a loopbce test that was incorrectly
written to detect an overflow but had a off-by-one (on the
conservative side), so it unexpectly passed with this CL; I
changed it to really trigger the overflow as intended.
Change-Id: Ib5abade337db46b8811425afebad4719b6e46c4a
Reviewed-on: https://go-review.googlesource.com/105635
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
To be effective, this also requires being able to relax constraints
on min/max bound inclusiveness; they are now exposed through a flags,
and prove has been updated to handle it correctly.
Change-Id: I3490e54461b7b9de8bc4ae40d3b5e2fa2d9f0556
Reviewed-on: https://go-review.googlesource.com/104041
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Test both minimum and maximum bound, and prepare
formatting for more advanced tests (inclusive / esclusive bounds).
Change-Id: Ibe432916d9c938343bc07943798bc9709ad71845
Reviewed-on: https://go-review.googlesource.com/104040
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reuse findIndVar to discover induction variables, and then
register the facts we know about them into the facts table
when entering the loop block.
Moreover, handle "x+delta > w" while updating the facts table,
to be able to prove accesses to slices with constant offsets
such as slice[i-10].
Change-Id: I2a63d050ed58258136d54712ac7015b25c893d71
Reviewed-on: https://go-review.googlesource.com/104038
Run-TryBot: Giovanni Bajo <rasky@develer.com>
Reviewed-by: David Chase <drchase@google.com>
When a branch is followed, we apply the relation as described
in the domain relation table. In case the relation is in the
positive domain, we can also infer an unsigned relation if,
by that point, we know that both operands are non-negative.
Fixes#20393
Change-Id: Ieaf0c81558b36d96616abae3eb834c788dd278d5
Reviewed-on: https://go-review.googlesource.com/100278
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Reviewed-by: David Chase <drchase@google.com>
mips64 softfloat support is based on mips implementation and introduces
new enviroment variable GOMIPS64.
GOMIPS64 is a GOARCH=mips64{,le} specific option, for a choice between
hard-float and soft-float. Valid values are 'hardfloat' (default) and
'softfloat'. It is passed to the assembler as
'GOMIPS64_{hardfloat,softfloat}'.
Change-Id: I7f73078627f7cb37c588a38fb5c997fe09c56134
Reviewed-on: https://go-review.googlesource.com/108475
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
On amd64, Ctz must include special handling of zeros.
But the prove pass has enough information to detect whether the input
is non-zero, allowing a more efficient lowering.
Introduce new CtzNonZero ops to capture and use this information.
Benchmark code:
func BenchmarkVisitBits(b *testing.B) {
b.Run("8", func(b *testing.B) {
for i := 0; i < b.N; i++ {
x := uint8(0xff)
for x != 0 {
sink = bits.TrailingZeros8(x)
x &= x - 1
}
}
})
// and similarly so for 16, 32, 64
}
name old time/op new time/op delta
VisitBits/8-8 7.27ns ± 4% 5.58ns ± 4% -23.35% (p=0.000 n=28+26)
VisitBits/16-8 14.7ns ± 7% 10.5ns ± 4% -28.43% (p=0.000 n=30+28)
VisitBits/32-8 27.6ns ± 8% 19.3ns ± 3% -30.14% (p=0.000 n=30+26)
VisitBits/64-8 44.0ns ±11% 38.0ns ± 5% -13.48% (p=0.000 n=30+30)
Fixes#25077
Change-Id: Ie6e5bd86baf39ee8a4ca7cadcf56d934e047f957
Reviewed-on: https://go-review.googlesource.com/109358
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
This change implements math.Round as an intrinsic on ppc64x so it can be
done using a single instruction.
benchmark old ns/op new ns/op delta
BenchmarkRound-16 2.60 0.69 -73.46%
Change-Id: I9408363e96201abdfc73ced7bcd5f0c29db006a8
Reviewed-on: https://go-review.googlesource.com/109395
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
The previous change sped up the pure computation form of LeadingZeros8.
This places it somewhat close to the table lookup form.
Depending on something that varies from toolchain to toolchain
(alignment, perhaps?), the slowdown from ditching the table lookup
is either 20% or 5%.
This benchmark is the best case scenario for the table lookup:
It is in the L1 cache already.
I think we're close enough that we can switch to the computational version,
and trust that the memory effects and binary size savings will be worth it.
Code:
func f8(x uint8) { z = bits.LeadingZeros8(x) }
Before:
"".f8 STEXT nosplit size=34 args=0x8 locals=0x0
0x0000 00000 (x.go:7) TEXT "".f8(SB), NOSPLIT, $0-8
0x0000 00000 (x.go:7) FUNCDATA $0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
0x0000 00000 (x.go:7) FUNCDATA $1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
0x0000 00000 (x.go:7) MOVBLZX "".x+8(SP), AX
0x0005 00005 (x.go:7) MOVBLZX AL, AX
0x0008 00008 (x.go:7) LEAQ math/bits.len8tab(SB), CX
0x000f 00015 (x.go:7) MOVBLZX (CX)(AX*1), AX
0x0013 00019 (x.go:7) ADDQ $-8, AX
0x0017 00023 (x.go:7) NEGQ AX
0x001a 00026 (x.go:7) MOVQ AX, "".z(SB)
0x0021 00033 (x.go:7) RET
After:
"".f8 STEXT nosplit size=30 args=0x8 locals=0x0
0x0000 00000 (x.go:7) TEXT "".f8(SB), NOSPLIT, $0-8
0x0000 00000 (x.go:7) FUNCDATA $0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
0x0000 00000 (x.go:7) FUNCDATA $1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
0x0000 00000 (x.go:7) MOVBLZX "".x+8(SP), AX
0x0005 00005 (x.go:7) MOVBLZX AL, AX
0x0008 00008 (x.go:7) LEAL 1(AX)(AX*1), AX
0x000c 00012 (x.go:7) BSRL AX, AX
0x000f 00015 (x.go:7) ADDQ $-8, AX
0x0013 00019 (x.go:7) NEGQ AX
0x0016 00022 (x.go:7) MOVQ AX, "".z(SB)
0x001d 00029 (x.go:7) RET
Change-Id: Icc7db50a7820fb9a3da8a816d6b6940d7f8e193e
Reviewed-on: https://go-review.googlesource.com/108942
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
We currently rewrite
(TESTQ (MOVQconst [c] x)) into (TESTQconst [c] x)
and (TESTQconst [-1] x) into (TESTQ x x)
if x is a (MOVQconst [-1]) we will be stuck in the endless rewrite loop.
Don't perform the rewrite in such cases.
Fixes#25006
Change-Id: I77f561ba2605fc104f1e5d5c57f32e9d67a2c000
Reviewed-on: https://go-review.googlesource.com/108879
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Rewrite x<<1+c into x+x+c, which can be expressed as a single LEAQ/LEAL.
Bit of a special case, but the single-instruction
LEA is both shorter and faster than SHL then ADD.
Triggers 293 times during make.bash.
Change-Id: I3f09c8e9a8f3859d1eeed336f095fc3ada79c2c1
Reviewed-on: https://go-review.googlesource.com/108938
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
This triggers three times while building std,
once in image/png and twice in go/internal/gccgoimporter.
There are no instances in std in which a more aggressive
optimization would have triggered.
This doesn't necessarily avoid an allocation,
because escape analysis is already able in many cases
to use a temporary backing for the string,
but it does at a minimum avoid the runtime call and copy.
Fixes#24937
Change-Id: I7019e85638ba8cd7e2f03890e672558b858579bc
Reviewed-on: https://go-review.googlesource.com/108035
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Due to some recent optimizations related to the compare
instruction, DS-form load instructions started to be used
to load 8-byte go.strings. This can cause link time errors
if the go.string is not aligned to 4 bytes.
For DS-form instructions, the value in the offset field must
be a multiple of 4. If the offset is known at the time the
rules are processed, a DS-form load will not be chosen. But for
go.strings, the offset is not known at that time, but a
relocation is generated indicating that the linker should fill
in the DS relocation. When the linker tries to fill in the
relocation, if the offset is not aligned properly, a link error
will occur.
To fix this, when loading a go.string using MOVDload, the full
address of the go.string is generated and loaded into the base
register. Then the go.string is loaded with a 0 offset field.
Added a testcase that reproduces this problem.
Fixes#24799
Change-Id: I6a154e8e1cba64eae290be0fbcb608b75884ecdd
Reviewed-on: https://go-review.googlesource.com/107855
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
The escape analysis models the flow of "content" of X with a
level of "indirection" (OIND node) of X. This content can be
pointer dereference, or slice/string element. For the latter
case, the type of the OIND node should be the element type of
the slice/string. This CL fixes this. In particular, this
matters when the element type is pointerless, where the data
flow should not cause any escape.
Fixes#15730.
Change-Id: Iba9f92898681625e7e3ddef76ae65d7cd61c41e0
Reviewed-on: https://go-review.googlesource.com/107597
Reviewed-by: David Chase <drchase@google.com>
If both inputs are constant offsets from the same pointer then we
can evaluate NeqPtr and EqPtr at compile time. Triggers a few times
during all.bash. Removes a conditional branch in the following
code:
copy(x[1:], x[:])
This branch was recently added as an optimization in CL 94596. We
now skip the memmove if the pointers are equal. However, in the
above code we know at compile time that they are never equal.
Also, when the offset is variable, check if the offset is zero
rather than if the pointers are equal. For example:
copy(x[a:], x[:])
This would now skip the copy if a == 0, rather than if x + a == x.
Finally I've also added a rule to make IsNonNil true for pointers
to values on the stack. The nil check elimination pass will catch
these anyway, but eliminating them here might eliminate branches
earlier.
Change-Id: If72f436fef0a96ad0f4e296d3a1f8b6c3e712085
Reviewed-on: https://go-review.googlesource.com/106635
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
While writing CL 107315, I went back and forth for the syntax used for
constraints of build environments in which the architecture did not
support varitants ("plan9/amd64" vs "plan9/amd64/"). I eventually
settled for the latter because the code required less heuristics
(think parsing "plan9/386" vs "386/sse2") but there were a few
leftovers in code and comments.
Change-Id: I9d9a008f3814f9a1642609650eb571e7f1a675cf
Reviewed-on: https://go-review.googlesource.com/107338
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This CL makes the codegen testsuite automatically test all
architecture variants for architecture specified in tests. For
instance, if a test file specifies a "arm" test, it will be
automatically run on all GOARM variants (5,6,7), to increase
the coverage.
The CL also introduces a syntax to specify only a specific
variant (eg: "arm/7") in case the test makes sense only there.
The same syntax also allows to specify the operating system
in case it matters (eg: "plan9/386/sse2").
Fixes#24658
Change-Id: I2eba8b918f51bb6a77a8431a309f8b71af07ea22
Reviewed-on: https://go-review.googlesource.com/107315
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
And remove it from asmtest. Next CL will remove the whole
asmtest infrastructure.
Change-Id: I5851bf7c617456d62a3c6cffacf70252df7b056b
Reviewed-on: https://go-review.googlesource.com/107335
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The escape analysis models "loop depth". If the address of an
expression is assigned to something defined at a lower (outer)
loop depth, the escape analysis decides it escapes. However, it
uses the loop depth of the address operator instead of where
the RHS is defined. This causes an unnecessary escape if there is
an assignment inside a loop but the RHS is defined outside the
loop. This CL propagates the loop depth.
Fixes#24730.
Change-Id: I5ff1530688bdfd90561a7b39c8be9bfc009a9dae
Reviewed-on: https://go-review.googlesource.com/105257
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
I was wrong. There was a need to loop here.
Fixes#24761
Change-Id: If13b3ab72febde930bdaebdddd1c05e0d0446020
Reviewed-on: https://go-review.googlesource.com/105615
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
And delete them from asm_test.
Also delete an arm64 cmov test has been already ported to the new test
harness.
Change-Id: I4458721e1f512bc9ecbbe1c22a2c9c7109ad68fe
Reviewed-on: https://go-review.googlesource.com/106335
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
The check was previously disallowing package main from even importing
a non-function symbol named "main".
Fixes#24801.
Change-Id: I849b9713890429f0a16860ef16b5dc7e970d04a4
Reviewed-on: https://go-review.googlesource.com/106120
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
And delete them from asm_test.
Change-Id: I24f421b87e8cb4770c887a6dfd58eacd0088947d
Reviewed-on: https://go-review.googlesource.com/106056
Reviewed-by: Keith Randall <khr@golang.org>
And delete them from asm_test.
Change-Id: I9a75efe9858ef9d7ac86065f860c2ae3f25b0941
Reviewed-on: https://go-review.googlesource.com/105597
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Also, when statically building itabs, compare *types.Sym instead of
name alone so that method sets with duplicate non-exported methods are
handled correctly.
Fixes#24693.
Change-Id: I2db8a3d6e80991a71fef5586a15134b6de116269
Reviewed-on: https://go-review.googlesource.com/105039
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Previously, constant pointer-typed expressions could use either Mpint
or NilVal as their Val depending on their construction, but const.go
expects each type to have a single corresponding Val kind.
This CL changes pointer-typed expressions to exclusively use Mpint.
Fixes#21221.
Change-Id: I6ba36c9b11eb19a68306f0b296acb11a8c254c41
Reviewed-on: https://go-review.googlesource.com/105315
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Multi-byte comparison operations were used on amd64, arm64, i386
and s390x for comparisons with constant arrays, but only amd64 and
i386 for comparisons with string constants. This CL combines the
check for platform capability, since they have the same requirements,
and also enables both on ppc64le which also supports load merging.
Note that these optimizations currently use little endian byte order
which results in byte reversal instructions on s390x. This should
be fixed at some point.
Change-Id: Ie612d13359b50c77f4d7c6e73fea4a59fa11f322
Reviewed-on: https://go-review.googlesource.com/102558
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
And delete them from asm_test.
Change-Id: I0e33d58274951ab5acb67b0117b60ef617ea887a
Reviewed-on: https://go-review.googlesource.com/105735
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Method expressions with anonymous receiver types like "struct { T }.m"
require wrapper functions, which we weren't always creating. This in
turn resulted in linker errors.
This CL ensures that we generate wrapper functions for any anonymous
receiver types used in a method expression.
Fixes#22444.
Change-Id: Ia8ac27f238c2898965e57b82a91d959792d2ddd4
Reviewed-on: https://go-review.googlesource.com/105044
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
There were multiple ad hoc ways to create method symbols, with subtle
and confusing differences between them. This CL unifies them into a
single well-documented encoding and implementation.
This introduces some inconsequential changes to symbol format for the
sake of simplicity and consistency. Two notable changes:
1) Symbol construction is now insensitive to the package currently
being compiled. Previously, non-exported methods on anonymous types
received different method symbols depending on whether the method was
local or imported.
2) Symbols for method values parenthesized non-pointer receiver types
and non-exported method names, and also always package-qualified
non-exported method names. Now they use the same rules as normal
method symbols.
The methodSym function is also now stricter about rejecting
non-sensical method/receiver combinations. Notably, this means that
typecheckfunc needs to call addmethod to validate the method before
calling declare, which also means we no longer emit errors about
redeclaring bogus methods.
Change-Id: I9501c7a53dd70ef60e5c74603974e5ecc06e2003
Reviewed-on: https://go-review.googlesource.com/104876
Reviewed-by: Robert Griesemer <gri@golang.org>
Since it's been reliably failing on one of the linux-arm builders
(arm5spacemonkey) for a long time.
Updates #24221.
Change-Id: I8fccc7e16631de497ccc2c285e510a110a93ad95
Reviewed-on: https://go-review.googlesource.com/104535
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
And delete them from asm_test.
Change-Id: Id533130470da9176a401cb94972f626f43a62148
Reviewed-on: https://go-review.googlesource.com/103656
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
The logic in addBranchRestrictions didn't allow to correctly
model OpIs(Slice)Bound for signed domain, and it was also partly
implemented within addRestrictions.
Thanks to the previous changes, it is now possible to handle
the negative conditions correctly, so that we can learn
both signed/LT + unsigned/LT on the positive side, and
signed/GE + unsigned/GE on the negative side (but only if
the index can be proved to be non-negative).
This is able to prove ~50 more slice accesses in std+cmd.
Change-Id: I9858080dc03b16f85993a55983dbc4b00f8491b0
Reviewed-on: https://go-review.googlesource.com/104037
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Don't report errors if we don't have a correct type switch
guard; instead ignore it and leave it to the type-checker
to report the error. This leads to better error messages
concentrating on the type switch guard rather than errors
around (confusing) syntactic details.
Also clean up some code setting up AssertExpr (they never
have a nil Type field) and remove some incorrect TODOs.
Fixes#24470.
Change-Id: I69512f36e0417e3b5ea9c8856768e04b19d654a8
Reviewed-on: https://go-review.googlesource.com/103615
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
When test/run script was removed, these two tests
were changed to be executed by test/run.go.
Because errchk does not exit with non-zero status on
errors, they were silently failing for a while.
This change makes 2 things:
1. Compile tested packages in GOROOT/test to match older runner script
behavior (strictly required only in bug345, optional in bug248)
2. Check command output with "(?m)^BUG" regexp.
It approximates older `grep -q '^BUG' that was used before.
See referenced issue for detailed explanation.
Fixes#24629
Change-Id: Ie888dcdb4e25cdbb19d434bbc5cb03eb633e9ee8
Reviewed-on: https://go-review.googlesource.com/104095
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
CL 38338 introduced SSA rules to optimize two types of pointer equality
tests: a pointer compared with itself, and comparison of addresses taken
of two symbols which may have the same base. This patch adds rules to
apply the same optimization to pointer inequality tests, which also ensures
that two pointers to zero-width types cannot be both equal and unequal
at the same time.
Fixes#24503.
Change-Id: Ic828aeb86ae2e680caf66c35f4c247674768a9ba
Reviewed-on: https://go-review.googlesource.com/102275
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
And delete them from asm_test.
Change-Id: Idfe1249052d82d15b9c30b292c78656a0bf7b48d
Reviewed-on: https://go-review.googlesource.com/103315
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
This change modifies the codegen test harness driver so that it no
longer modifies the environment GOOS/GOARCH, since that seems to cause
flakiness in other concurrently-running tests.
The change also enables the codegen tests in run.go.
Fixes#24538
Change-Id: I997ac1eb38eb92054efff67fe5c4d3cccc86412b
Reviewed-on: https://go-review.googlesource.com/103455
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The escape_because.go test file (which tests the "because" escape
explainations printed by `-m -m`) cointains a machine-generated list
of all the escape reasons seen in the escape tests.
The list appears to be outdated; moreove a new escape reason was added
in CL 102895. This change re-generates the list.
Change-Id: Idc721c6bbfe9516895b5cf1e6d09b77deda5a3dd
Reviewed-on: https://go-review.googlesource.com/103375
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This change makes `-m -m` print a better explanation for the case
where a slice is marked as escaping and heap-allocated because it
has a non-constant len/cap.
Fixes#24578
Change-Id: I0ebafb77c758a99857d72b365817bdba7b446cc0
Reviewed-on: https://go-review.googlesource.com/102895
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
In expandmeth, we call expand1/expand0 to build a list of all
candidate methods to promote, and then we use dotpath to prune down
which names actually resolve to a promoted method and how.
However, previously we still computed "followsptr" based on the
expand1/expand0 traversal (which is depth-first), rather than
dotpath (which is breadth-first). The result is that we could
sometimes end up miscomputing whether a particular promoted method
involves a pointer traversal, which could result in bad code
generation for method trampolines.
Fixes#24547.
Change-Id: I57dc014466d81c165b05d78b98610dc3765b7a90
Reviewed-on: https://go-review.googlesource.com/102618
Reviewed-by: Robert Griesemer <gri@golang.org>
And delete them from asm_test.
Change-Id: I34fcf85ae8ce09cd146fe4ce6a0ae7616bd97e2d
Reviewed-on: https://go-review.googlesource.com/102296
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
And remove them from asm_test.
Change-Id: I1ca29b40546d6de06f20bfd550ed8ff87f495454
Reviewed-on: https://go-review.googlesource.com/102115
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
And delete them from asm_test.
Change-Id: I64c512bfef3b3da6db5c5d29277675dade28b8ab
Reviewed-on: https://go-review.googlesource.com/101595
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
The atomic add instructions modify the condition code and so need to
be marked as clobbering flags.
Fixes#24449.
Change-Id: Ic69c8d775fbdbfb2a56c5e0cfca7a49c0d7f6897
Reviewed-on: https://go-review.googlesource.com/101455
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
And delete them from asm_test.
Change-Id: I3cf0934706a640136cb0f646509174f8c1bf3363
Reviewed-on: https://go-review.googlesource.com/101395
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
And delete them from asm_test.
Change-Id: Ibdaca3496eefc73c731b511ddb9636a1f3dff68c
Reviewed-on: https://go-review.googlesource.com/100915
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
And delete them from asm_test.
Change-Id: I29c8d098a8893e6b669b6272a2f508985ac9d618
Reviewed-on: https://go-review.googlesource.com/100876
Reviewed-by: Cherry Zhang <cherryyz@google.com>
This reverts commit 080187f4f7.
It broke build of golang.org/x/exp/shiny/iconvg
See issue 24395 for details
Change-Id: Ifd6134f6214e6cee40bd3c63c32941d5fc96ae8b
Reviewed-on: https://go-review.googlesource.com/100755
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
This change ports all the remaining tests checking that small memmoves
are replaced with MOVs to the new codegen test harness, and deletes
them from the asm_test file.
Change-Id: I01c94b441e27a5d61518035af62d62779dafeb56
Reviewed-on: https://go-review.googlesource.com/100476
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Add tests for the "negative size argument in make.*" and "size argument
too large in make.*" error messages to appear at call sites in case the
size is a const defined on another line.
As suggested by Matthew in a comment on CL 69910.
Change-Id: I5c33d4bec4e3d20bb21fe8019df27999997ddff3
Reviewed-on: https://go-review.googlesource.com/100395
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
As a side effect of working on mid-stack inlining, we've fixed support
for inlining variadic functions. Might as well enable it.
Change-Id: I7f555f8b941969791db7eb598c0b49f6dc0820aa
Reviewed-on: https://go-review.googlesource.com/100456
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Currently, order desugars map assignment operations like
m[k] op= r
into
m[k] = m[k] op r
which in turn is transformed during walk into:
tmp := *mapaccess(m, k)
tmp = tmp op r
*mapassign(m, k) = tmp
However, this is suboptimal, as we could instead produce just:
*mapassign(m, k) op= r
One complication though is if "r == 0", then "m[k] /= r" and "m[k] %=
r" will panic, and they need to do so *before* calling mapassign,
otherwise we may insert a new zero-value element into the map.
It would be spec compliant to just emit the "r != 0" check before
calling mapassign (see #23735), but currently these checks aren't
generated until SSA construction. For now, it's simpler to continue
desugaring /= and %= into two map indexing operations.
Fixes#23661.
Change-Id: I46e3739d9adef10e92b46fdd78b88d5aabe68952
Reviewed-on: https://go-review.googlesource.com/91557
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
cmd/asm now supports three-operand form of IMUL,
so instead of using IMUL with resultInArg0, emit IMUL3 instruction.
This results in less redundant MOVs where SSA assigns
different registers to input[0] and dst arguments.
Note: these have exactly the same encoding when reg0=reg1:
IMUL3x $const, reg0, reg1
IMULx $const, reg
Two-operand IMULx is like a crippled IMUL3x, with dst fixed to input[0].
This is why we don't bother to generate IMULx for the case where
dst is the same as input[0].
Change-Id: I4becda475b3dffdd07b6fdf1c75bacc82af654e4
Reviewed-on: https://go-review.googlesource.com/99656
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Reviewed-by: Keith Randall <khr@golang.org>
Remove old tests from asm_test.
Change-Id: Ib408ec7faa60068bddecf709b93ce308e0ef665a
Reviewed-on: https://go-review.googlesource.com/100075
Reviewed-by: Alberto Donizetti <alb.donizetti@gmail.com>
This change adds a README file inside the test/codegen directory,
explaining how to run the codegen tests and the syntax of the regexps
comments used to match assembly instructions.
Change-Id: Ica4eb3ffa9c6975371538cc8ae0ac3c1a3a03baf
Reviewed-on: https://go-review.googlesource.com/99156
Reviewed-by: Keith Randall <khr@golang.org>
And delete them from asm_go.
Change-Id: I0057cbd90ca55fa51c596e32406e190f3866f93e
Reviewed-on: https://go-review.googlesource.com/99815
Reviewed-by: Keith Randall <khr@golang.org>
Only RotateLeft{64,32} were tested, and just for ppc64. This CL adds
tests for RotateLeft{64,32,16,8} on arm64 and amd64/386, for the cases
where the calls are actually instrinsified.
RotateLeft tests (the last ones for math/bits functions) are deleted
from asm_test.
This CL also adds a space between the "//" and the arch name in the
comments, to uniform this file to the style used in all the other
files.
Change-Id: Ifc2a27261d70bcc294b4ec64490d8367f62d2b89
Reviewed-on: https://go-review.googlesource.com/99596
Reviewed-by: Giovanni Bajo <rasky@develer.com>
This adds four new deductions to the prove pass, all related to adding
or subtracting one from a value. This is the first hint of actual
arithmetic relations in the prove pass.
The most effective of these is
x-1 >= w && x > min ⇒ x > w
This helps eliminate bounds checks in code like
if x > 0 {
// do something with s[x-1]
}
Altogether, these deductions prove an additional 260 branches in std
and cmd. Furthermore, they will let us eliminate some tricky
compiler-inserted panics in the runtime that are interfering with
static analysis.
Fixes#23354.
Change-Id: I7088223e0e0cd6ff062a75c127eb4bb60e6dce02
Reviewed-on: https://go-review.googlesource.com/87480
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Alexandru Moșoi <alexandru@mosoi.ro>
This adds a few simple deductions to the prove pass' fact table to
derive unsigned concrete limits from signed concrete limits where
possible.
This tweak lets the pass prove 70 additional branch conditions in std
and cmd.
This is based on a comment from the recently-deleted factsTable.get:
"// TODO: also use signed data if lim.min >= 0".
Change-Id: Ib4340249e7733070f004a0aa31254adf5df8a392
Reviewed-on: https://go-review.googlesource.com/87479
Reviewed-by: Alexandru Moșoi <alexandru@mosoi.ro>
Reviewed-by: Keith Randall <khr@golang.org>
Currently the prove pass uses implication queries. For each block, it
collects the set of branch conditions leading to that block, and
queries this fact table for whether any of these facts imply the
block's own branch condition (or its inverse). This works remarkably
well considering it doesn't do any deduction on these facts, but it
has various downsides:
1. It requires an implementation both of adding facts to the table and
determining implications. These are very nearly duals of each
other, but require separate implementations. Likewise, the process
of asserting facts of dominating branch conditions is very nearly
the dual of the process of querying implied branch conditions.
2. It leads to less effective use of derived facts. For example, the
prove pass currently derives facts about the relations between len
and cap, but can't make use of these unless a branch condition is
in the exact form of a derived fact. If one of these derived facts
contradicts another fact, it won't notice or make use of this.
This CL changes the approach of the prove pass to instead use
*contradiction* instead of implication. Rather than ever querying a
branch condition, it simply adds branch conditions to the fact table.
If this leads to a contradiction (specifically, it makes the fact set
unsatisfiable), that branch is impossible and can be cut. As a result,
1. We can eliminate the code for determining implications
(factsTable.get disappears entirely). Also, there is now a single
implementation of visiting and asserting branch conditions, since
we don't have to flip them around to treat them as facts in one
place and queries in another.
2. Derived facts can be used effectively. It doesn't matter *why* the
fact table is unsatisfiable; a contradiction in any of the facts is
enough.
3. As an added benefit, it's now quite easy to avoid traversing beyond
provably-unreachable blocks. In contrast, the current
implementation always visits all blocks.
The prove pass already has nearly all of the mechanism necessary to
compute unsatisfiability, which means this both simplifies the code
and makes it more powerful.
The only complication is that the current implication procedure has a
hack for dealing with the 0 <= Args[0] condition of OpIsInBounds and
OpIsSliceInBounds. We replace this with asserting the appropriate fact
when we process one of these conditions. This seems much cleaner
anyway, and works because we can now take advantage of derived facts.
This has no measurable effect on compiler performance.
Effectiveness:
There is exactly one condition in all of std and cmd that this fails
to prove that the old implementation could: (int64(^uint(0)>>1) < x)
in encoding/gob. This can never be true because x is an int, and it's
basically coincidence that the old code gets this. (For example, it
fails to prove the similar (x < ^int64(^uint(0)>>1)) condition that
immediately precedes it, and even though the conditions are logically
unrelated, it wouldn't get the second one if it hadn't first processed
the first!)
It does, however, prove a few dozen additional branches. These come
from facts that are added to the fact table about the relations
between len and cap. These were almost never queried directly before,
but could lead to contradictions, which the unsat-based approach is
able to use.
There are exactly two branches in std and cmd that this implementation
proves in the *other* direction. This sounds scary, but is okay
because both occur in already-unreachable blocks, so it doesn't matter
what we chose. Because the fact table logic is sound but incomplete,
it fails to prove that the block isn't reachable, even though it is
able to prove that both outgoing branches are impossible. We could
turn these blocks into BlockExit blocks, but it doesn't seem worth the
trouble of the extra proof effort for something that happens twice in
all of std and cmd.
Tests:
This CL updates test/prove.go to change the expected messages because
it can no longer give a "reason" why it proved or disproved a
condition. It also adds a new test of a branch it couldn't prove
before.
It mostly guts test/sliceopt.go, removing everything related to slice
bounds optimizations and moving a few relevant tests to test/prove.go.
Much of this test is actually unreachable. The new prove pass figures
this out and doesn't try to prove anything about the unreachable
parts. The output on the unreachable parts is already suspect because
anything can be proved at that point, so it's really just a regression
test for an algorithm the compiler no longer uses.
This is a step toward fixing #23354. That issue is quite easy to fix
once we can use derived facts effectively.
Change-Id: Ia48a1b9ee081310579fe474e4a61857424ff8ce8
Reviewed-on: https://go-review.googlesource.com/87478
Reviewed-by: Keith Randall <khr@golang.org>
And delete them from the asm_test.go file.
Change-Id: I124c8c352299646ec7db0968cdb0fe59a3b5d83d
Reviewed-on: https://go-review.googlesource.com/99475
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
This was already done for normal parameters, and the same logic
applies for receiver parameters too.
Updates #24305.
Change-Id: Ia2a46f68d14e8fb62004ff0da1db0f065a95a1b7
Reviewed-on: https://go-review.googlesource.com/99335
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This recently added arm64 memmove codegen check:
func movesmall() {
// arm64:-"memmove"
x := [...]byte{1, 2, 3, 4, 5, 6, 7}
copy(x[1:], x[:])
}
is not correct, for two reasons:
1. regexps are matched from the start of the disasm line (excluding
line information). This mean that a negative -"memmove" check will
pass against a 'CALL runtime.memmove' line because the line does
not start with 'memmove' (its starts with CALL...).
The way to specify no 'memmove' match whatsoever on the line is
-".*memmove"
2. AFAIK comments on their own line are matched against the first
subsequent non-comment line. So the code above only verifies that
the x := ... line does not generate a memmove. The comment should
be moved near the copy() line, if it's that one we want to not
generate a memmove call.
The fact that the test above is not effective can be checked by
running `go run run.go -v codegen` in the toplevel test directory with
a go1.10 toolchain (that does not have the memmove-elision
optimization). The test will still pass (it shouldn't).
This change changes the regexp to -".*memmove" and moves it near the
line it needs to (not)match.
Change-Id: Ie01ef4d775e77d92dc8d8b7856b89b200f5e5ef2
Reviewed-on: https://go-review.googlesource.com/98977
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
And remove them from ssa_test.
Change-Id: If767af662801219774d1bdb787c77edfa6067770
Reviewed-on: https://go-review.googlesource.com/98976
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Current implementation doesn't consider MOVDreg type operand and fail to combine
it into larger store. This patch fixes the issue.
Fixes#24242
Change-Id: I7d68697f80e76f48c3528ece01a602bf513248ec
Reviewed-on: https://go-review.googlesource.com/98397
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
And remove them from ssa_test.
Change-Id: I3efac5fea529bb0efa2dae32124530482ba5058e
Reviewed-on: https://go-review.googlesource.com/98815
Reviewed-by: Keith Randall <khr@golang.org>
And remove them from ssa_test.
Change-Id: Ib5de5c0d908f23915e0847eca338cacf2fa5325b
Reviewed-on: https://go-review.googlesource.com/98795
Reviewed-by: Giovanni Bajo <rasky@develer.com>
This change move bits.Len* intrinsification tests to the new codegen
test harness, removing them from the old ssa_test file. Five different
test functions (one for each bit.Len function tested) was used, to
avoid possible unwanted interactions between multiple calls inside one
function.
Change-Id: Iffd5be55b58e88597fa30a562a28dacb01236d8b
Reviewed-on: https://go-review.googlesource.com/98156
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
This CL moves the load/store combining tests into asmcheck.
In addition at being more compact, it's also now easier to
spot what it is missing in each architecture.
While doing so, I think I uncovered a bug in ppc64le and arm64
rules, because they fail to load/store combine in non-trivial
functions. Not sure why, I'll open an issue.
Change-Id: Ia1572d53c0553d9104f3e52b95e4d1768a8440a3
Reviewed-on: https://go-review.googlesource.com/98441
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Before this change, in case of any failure, asmcheck was
dumping to stderr the whole output of compile -S, which
can be very long if it contains multiple functions.
Make it so it filters the output to only display the
assembly output of functions for which at least one opcode
check failed. This greatly simplifies debugging.
Change-Id: I1bbf54473b8252a3384e2c1dade82d926afc119d
Reviewed-on: https://go-review.googlesource.com/98444
Run-TryBot: Giovanni Bajo <rasky@develer.com>
Reviewed-by: Keith Randall <khr@golang.org>
Currently, the top-level testsuite always uses whatever version
of Go is found in the PATH to execute all the tests. This
forces the developers to tweak the PATH to run the testsuite.
Change it to use the same version of Go used to run run.go.
This allows developers to run the testsuite using the tip
compiler by simply saying "../bin/go run run.go".
I think this is a better solution compared to always forcing
"../bin/go", because it allows developers to run the testsuite
using different Go versions, for instance to check if a new
test is fixed in tip compared to the installed compiler.
Fixes#24217
Change-Id: I41b299c753b6e77c41e28be9091b2b630efea9d2
Reviewed-on: https://go-review.googlesource.com/98439
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
In RET instruction, the operand is the return jump's target,
which should be put in Prog.To.
Add an action "buildrundir" to the test driver, which builds
(compile+assemble+link) the code in a directory and runs the
resulting binary.
Fixes#23838.
Change-Id: I7ebe7eda49024b40a69a24857322c5ca9c67babb
Reviewed-on: https://go-review.googlesource.com/94175
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
This avoid simple bugs like "ADD" matching "FADD". Obviously
"ADD" will still match "ADDQ" so some care is still required
in this regard, but at least a first class of possible errors
is taken care of.
Change-Id: I7deb04c31de30bedac9c026d9889ace4a1d2adcb
Reviewed-on: https://go-review.googlesource.com/97817
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Reviewed-by: Keith Randall <khr@golang.org>
asmcheck comments now support a compact form of specifying
multiple checks for each platform, using the following syntax:
amd64:"SHL\t[$]4","SHR\t[$]4"
Negative checks are also parsed using the following syntax:
amd64:-"ROR"
though they are still not working.
Moreover, out-of-line comments have been implemented. This
allows to specify asmchecks on comment-only lines, that will
be matched on the first subsequent non-comment non-empty line.
// amd64:"XOR"
// arm:"EOR"
x ^= 1
Change-Id: I110c7462fc6a5c70fd4af0d42f516016ae7f2760
Reviewed-on: https://go-review.googlesource.com/97816
Reviewed-by: Keith Randall <khr@golang.org>
When the slice/string length is very large,
probably artifically large as in CL 97523,
adding BX (length) to R11 (pointer) overflows.
As a result, checking DI < R11 yields the wrong result.
Since they will be equal when the loop is done,
just check DI != R11 instead.
Yes, the pointer itself could overflow, but if that happens,
something else has gone pretty wrong; not our concern here.
Fixes#24187
Change-Id: I2f60fc6ccae739345d01bc80528560726ad4f8c6
Reviewed-on: https://go-review.googlesource.com/97802
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
The top-level test harness is modified to support a new kind
of test: "asmcheck". This is meant to replace asm_test.go
as an easier and more readable way to test code generation.
I've added a couple of codegen tests to get initial feedback
on the syntax. I've created them under a common "codegen"
subdirectory, so that it's easier to run them all with
"go run run.go -v codegen".
The asmcheck syntax allows to insert line comments that
can specify a regular expression to match in the assembly code,
for multiple architectures (the testsuite will automatically
build each testfile multiple times, one per mentioned architecture).
Negative matches are unsupported for now, so this cannot fully
replace asm_test yet.
Change-Id: Ifdbba389f01d55e63e73c99e5f5449e642101d55
Reviewed-on: https://go-review.googlesource.com/97355
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Alberto Donizetti <alb.donizetti@gmail.com>
OCOMPLIT stores the pre-typechecked type in n.Right, and then moves it
to n.Type. However, it wasn't clearing n.Right, so n.Right continued
to point to the OTYPE node. (Exception: slice literals reused n.Right
to store the array length.)
When exporting inline function bodies, we don't expect to need to save
any type aliases. Doing so wouldn't be wrong per se, but it's
completely unnecessary and would just bloat the export data.
However, reexportdep (whose role is to identify types needed by inline
function bodies) uses a generic tree traversal mechanism, which visits
n.Right even for O{ARRAY,MAP,STRUCT}LIT nodes. This means it finds the
OTYPE node, and mistakenly interpreted that the type alias needs to be
exported.
The straight forward fix is to just clear n.Right when typechecking
composite literals.
Fixes#24173.
Change-Id: Ia2d556bfdd806c83695b08e18b6cd71eff0772fc
Reviewed-on: https://go-review.googlesource.com/97719
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
Otherwise, the error can be confusing if one forgets or doesn't know
that the builtin is being shadowed, which is not common practice.
Fixes#22822.
Change-Id: I735393b5ce28cb83815a1c3f7cd2e7bb5080a32d
Reviewed-on: https://go-review.googlesource.com/97455
Reviewed-by: Robert Griesemer <gri@golang.org>
This change enables printing of relative column information if a
prior line directive specified a valid column. If there was no
line directive, or the line directive didn't specify a column
(or the -C flag is specified), no column information is shown in
file positions.
Implementation: Column values (and line values, for that matter)
that are zero are interpreted as "unknown". A line directive that
doesn't specify a column records that as a zero column in the
respective PosBase data structure. When computing relative columns,
a relative value is zero of the base's column value is zero.
When formatting a position, a zero column value is not printed.
To make this work without special cases, the PosBase for a file
is given a concrete (non-0:0) position 1:1 with the PosBase's
line and column also being 1:1. In other words, at the position
1:1 of a file, it's relative positions are starting with 1:1 as
one would expect.
In the package syntax, this requires self-recursive PosBases for
file bases, matching what cmd/internal/src.PosBase was already
doing. In src.PosBase, file and inlining bases also need to be
based at 1:1 to indicate "known" positions.
This change completes the cmd/compiler part of the issue below.
Fixes#22662.
Change-Id: I6c3d2dee26709581fba0d0261b1d12e93f1cba1a
Reviewed-on: https://go-review.googlesource.com/97375
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
The first word of an interface is a pointer, but for the purposes
of GC we don't need to treat it as such.
1. If it is a non-empty interface, the pointer points to an itab
which is always in persistentalloc space.
2. If it is an empty interface, the pointer points to a _type.
a. If it is a compile-time-allocated type, it points into
the read-only data section.
b. If it is a reflect-allocated type, it points into the Go heap.
Reflect is responsible for keeping a reference to
the underlying type so it won't be GCd.
If we ever have a moving GC, we need to change this for 2b (as
well as scan itabs to update their itab._type fields).
Write barriers on the first word of interfaces have already been removed.
Change-Id: I643e91d7ac4de980ac2717436eff94097c65d959
Reviewed-on: https://go-review.googlesource.com/97518
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
We accidentally overlooked needing to still visit Ninit for OIF
statements with constant conditions in golang.org/cl/96778.
Fixes#24120.
Change-Id: I5b341913065ff90e1163fb872b9e8d47e2a789d2
Reviewed-on: https://go-review.googlesource.com/97475
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Extend cmd/internal/src.PosBase to track column information,
and adjust the meaning of the PosBase position to mean the
position at which the PosBase's relative (line, col) position
starts (rather than indicating the position of the //line
directive). Because this semantic change is made in the
compiler's noder, it doesn't affect the logic of src.PosBase,
only its test setup (where PosBases are constructed with
corrected incomming positions). In short, src.PosBase now
matches syntax.PosBase with respect to the semantics of
src.PosBase.pos.
For #22662.
Change-Id: I5b1451cb88fff3f149920c2eec08b6167955ce27
Reviewed-on: https://go-review.googlesource.com/96535
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
When we go from a branch block to a plain block, reset the
branch prediction bit. Downstream passes asssume that if the
branch prediction is set, then the block has 2 successors.
Fixes#23504
Change-Id: I2898ec002228b2e34fe80ce420c6939201c0a5aa
Reviewed-on: https://go-review.googlesource.com/88955
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
This replaces the contiguous heap arena mapping with a potentially
sparse mapping that can support heap mappings anywhere in the address
space.
This has several advantages over the current approach:
* There is no longer any limit on the size of the Go heap. (Currently
it's limited to 512GB.) Hence, this fixes#10460.
* It eliminates many failures modes of heap initialization and
growing. In particular it eliminates any possibility of panicking
with an address space conflict. This can happen for many reasons and
even causes a low but steady rate of TSAN test failures because of
conflicts with the TSAN runtime. See #16936 and #11993.
* It eliminates the notion of "non-reserved" heap, which was added
because creating huge address space reservations (particularly on
64-bit) led to huge process VSIZE. This was at best confusing and at
worst conflicted badly with ulimit -v. However, the non-reserved
heap logic is complicated, can race with other mappings in non-pure
Go binaries (e.g., #18976), and requires that the entire heap be
either reserved or non-reserved. We currently maintain the latter
property, but it's quite difficult to convince yourself of that, and
hence difficult to keep correct. This logic is still present, but
will be removed in the next CL.
* It fixes problems on 32-bit where skipping over parts of the address
space leads to mapping huge (and never-to-be-used) metadata
structures. See #19831.
This also completely rewrites and significantly simplifies
mheap.sysAlloc, which has been a source of many bugs. E.g., #21044,
#20259, #18651, and #13143 (and maybe #23222).
This change also makes it possible to allocate individual objects
larger than 512GB. As a result, a few tests that expected huge
allocations to fail needed to be changed to make even larger
allocations. However, at the moment attempting to allocate a humongous
object may cause the program to freeze for several minutes on Linux as
we fall back to probing every page with addrspace_free. That logic
(and this failure mode) will be removed in the next CL.
Fixes#10460.
Fixes#22204 (since it rewrites the code involved).
This slightly slows down compilebench and the x/benchmarks garbage
benchmark.
name old time/op new time/op delta
Template 184ms ± 1% 185ms ± 1% ~ (p=0.065 n=10+9)
Unicode 86.9ms ± 3% 86.3ms ± 1% ~ (p=0.631 n=10+10)
GoTypes 599ms ± 0% 602ms ± 0% +0.56% (p=0.000 n=10+9)
Compiler 2.87s ± 1% 2.89s ± 1% +0.51% (p=0.002 n=9+10)
SSA 7.29s ± 1% 7.25s ± 1% ~ (p=0.182 n=10+9)
Flate 118ms ± 2% 118ms ± 1% ~ (p=0.113 n=9+9)
GoParser 147ms ± 1% 148ms ± 1% +1.07% (p=0.003 n=9+10)
Reflect 401ms ± 1% 404ms ± 1% +0.71% (p=0.003 n=10+9)
Tar 175ms ± 1% 175ms ± 1% ~ (p=0.604 n=9+10)
XML 209ms ± 1% 210ms ± 1% ~ (p=0.052 n=10+10)
(https://perf.golang.org/search?q=upload:20171231.4)
name old time/op new time/op delta
Garbage/benchmem-MB=64-12 2.23ms ± 1% 2.25ms ± 1% +0.84% (p=0.000 n=19+19)
(https://perf.golang.org/search?q=upload:20171231.3)
Relative to the start of the sparse heap changes (starting at and
including "runtime: fix various contiguous bitmap assumptions"),
overall slowdown is roughly 1% on GC-intensive benchmarks:
name old time/op new time/op delta
Template 183ms ± 1% 185ms ± 1% +1.32% (p=0.000 n=9+9)
Unicode 84.9ms ± 2% 86.3ms ± 1% +1.65% (p=0.000 n=9+10)
GoTypes 595ms ± 1% 602ms ± 0% +1.19% (p=0.000 n=9+9)
Compiler 2.86s ± 0% 2.89s ± 1% +0.91% (p=0.000 n=9+10)
SSA 7.19s ± 0% 7.25s ± 1% +0.75% (p=0.000 n=8+9)
Flate 117ms ± 1% 118ms ± 1% +1.10% (p=0.000 n=10+9)
GoParser 146ms ± 2% 148ms ± 1% +1.48% (p=0.002 n=10+10)
Reflect 398ms ± 1% 404ms ± 1% +1.51% (p=0.000 n=10+9)
Tar 173ms ± 1% 175ms ± 1% +1.17% (p=0.000 n=10+10)
XML 208ms ± 1% 210ms ± 1% +0.62% (p=0.011 n=10+10)
[Geo mean] 369ms 373ms +1.17%
(https://perf.golang.org/search?q=upload:20180101.2)
name old time/op new time/op delta
Garbage/benchmem-MB=64-12 2.22ms ± 1% 2.25ms ± 1% +1.51% (p=0.000 n=20+19)
(https://perf.golang.org/search?q=upload:20180101.3)
Change-Id: I5daf4cfec24b252e5a57001f0a6c03f22479d0f0
Reviewed-on: https://go-review.googlesource.com/85887
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
The scanner assumed that ~ really meant ^, which may be helpful when
coming from C. But ~ is not a valid Go token, and pretending that it
should be ^ can lead to confusing error messages. Better to be upfront
about it and complain about the invalid character in the first place.
This was code "inherited" from the original yacc parser which was
derived from a C compiler. It's 10 years later and we can probably
assume that people are less confused about C and Go.
Fixes#23587.
Change-Id: I8d8f9b55b0dff009b75c1530d729bf9092c5aea6
Reviewed-on: https://go-review.googlesource.com/94160
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Assume that an expression that is not a function call in a defer/go
statement is indeed a function that is just missing its invocation.
Report the error but continue with a sane syntax tree.
Fixes#23586.
Change-Id: Ib45ebac57c83b3e39ae4a1b137ffa291dec5b50d
Reviewed-on: https://go-review.googlesource.com/94156
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Previously, if we typechecked a statement like
var x bool = p1.f == p2.f && p1.g == p2.g
we would correctly update the '&&' node's type from 'untyped bool' to
'bool', but the '==' nodes would stay 'untyped bool'. This is
inconsistent, and caused consistency checks during walk to fail.
This CL doesn't pass toolstash because it seems to slightly affect the
register allocator's heuristics. (Presumably 'untyped bool's were
previously making it all the way through SSA?)
Fixes#23414.
Change-Id: Ia85f8cfc69b5ba35dfeb157f4edf57612ecc3285
Reviewed-on: https://go-review.googlesource.com/94022
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
The tag was overwritten by the code for special handling unnamed
parameters.
Fixes#23045.
Change-Id: Ie2e1db3e902a07a2bbbc2a3424cea300f0a42cc3
Reviewed-on: https://go-review.googlesource.com/82775
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Per the language spec clarification in https://golang.org/cl/14727.
Updates #12576
Updates #12621
Change-Id: I1e459c3c11a571bd29582761faacaa9ca3178ba6
Reviewed-on: https://go-review.googlesource.com/91895
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The sub-word shifts need to sign-extend before shifting, to avoid
bringing in data from higher in the argument.
Fixes#23812
Change-Id: I0a95a0b49c48f3b40b85765bb4a9bb492be0cd73
Reviewed-on: https://go-review.googlesource.com/93716
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Fixes#23732
Disambiguate "too few" or "too many" values in struct
initializer messages by reporting the name of the literal.
After:
issue23732.go:27:3: too few values in Foo literal
issue23732.go:34:12: too many values in Bar literal
issue23732.go:40:6: too few values in Foo literal
issue23732.go:40:12: too many values in Bar literal
Change-Id: Ieca37298441d907ac78ffe960c5ab55741a362ef
Reviewed-on: https://go-review.googlesource.com/93277
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Now that the buffered write barrier is implemented for all
architectures, we can remove the old eager write barrier
implementation. This CL removes the implementation from the runtime,
support in the compiler for calling it, and updates some compiler
tests that relied on the old eager barrier support. It also makes sure
that all of the useful comments from the old write barrier
implementation still have a place to live.
Fixes#22460.
Updates #21640 since this fixes the layering concerns of the write
barrier (but not the other things in that issue).
Change-Id: I580f93c152e89607e0a72fe43370237ba97bae74
Reviewed-on: https://go-review.googlesource.com/92705
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Rick Hudson <rlh@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
When loading multiple elements of an array into a single register,
make sure we treat them as unsigned. When treated as signed, the
upper bits might all be set, causing the shift-or combo to clobber
the values higher in the register.
Fixes#23719.
Change-Id: Ic87da03e9bd0fe2c60bb214b99f846e4e9446052
Reviewed-on: https://go-review.googlesource.com/92335
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
The fix is CL 91035.
Build only with gccgo at the moment, as it hits issue #23546.
Updates #23545.
Change-Id: I3a1367bb31b04773d31f71016f8fd7bd1855d7b5
Reviewed-on: https://go-review.googlesource.com/89735
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The compiler allows code to have multiple differently-typed views of a
single argument. For instance, if we have
func f(x float64) {
y := *(*int64)(unsafe.Pointer(&x))
...
}
Then in SSA we get two OpArg ops, one with float64 type and one with
int64 type.
The compiler will try to reuse argument slots for spill slots. It
checks that the argument slot is dead by consulting an interference
graph.
When building the interference graph, we normally ignore cross-type
edges because the values on either end of that edge can't be allocated
to the same slot. (This is just a space-saving optimization.) This
rule breaks down when one of the values is an argument, because of the
multiple views described above. If we're spilling a float64, it is not
enough that the float64 version of x is dead; the int64 version of x
has to be dead also.
Remove the optimization of not recording interference edges if types
don't match. That optimization is incorrect if one of the values
connected by the edge is an argument.
Fixes#23522
Change-Id: I361f85d80fe3bc7249014ca2c3ec887c3dc30271
Reviewed-on: https://go-review.googlesource.com/89335
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
A Select Op could produce a value with upper 32 bits NOT zeroed,
for example, Div32 is lowered to (Select0 (DIVL x y)).
In theory, we could look into the argument of a Select to decide
whether the upper bits are zeroed. As it is late in release cycle,
just disable this optimization for Select for now.
Fixes#23305.
Change-Id: Icf665a2af9ccb0a7ba0ae00c683c9e349638bf85
Reviewed-on: https://go-review.googlesource.com/85736
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
My previous fix for issue 23179 was incomplete; it turns out that if
an unnamed parameter is below a specific size threshold, it gets
register-promoted away by the compiler (hence not encountered during
some parts of DWARF inline info processing), but if it is sufficiently
large, it is allocated to the stack as a named variable and treated as
a regular parameter by DWARF generation. Interestingly, something in
the ppc64le build of k8s causes an unnamed parameter to be retained
(where on amd64 it is deleted), meaning that this wasn't caught in my
amd64 testing.
The fix is to insure that "_" params are treated in the same way that
"~r%d" return temps are when matching up post-optimization inlined
routine params with pre-inlining declarations. I've also updated the
test case to include a "_" parameter with a very large size, which
also triggers the bug on amd64.
Fixes#23179.
Change-Id: I961c84cc7a873ad3f8f91db098a5e13896c4856e
Reviewed-on: https://go-review.googlesource.com/84975
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
The helper routine for returning pre-inlining parameter declarations
wasn't properly handling the case where you have more than one
parameter named "_" in a function signature; this triggered a map
collision later on when the function was inlined and DWARF was
generated for the inlined routine instance.
Fixes#23179.
Change-Id: I12e5d6556ec5ce08e982a6b53666a4dcc1d22201
Reviewed-on: https://go-review.googlesource.com/84755
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
This allows errchk to be used with "go vet" output (as opposed to "go tool vet").
Change-Id: I0009a53c9cb74accd5bd3923c137d6dbf9e46326
Reviewed-on: https://go-review.googlesource.com/83836
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
We can't currently inline functions that contain closures anyway, so
just delete this budgeting code for now. Re-enable once we can (if
ever) inline functions with nested closures.
Updates #15561.
Fixes#23093.
Change-Id: Idc5f8e042ccfcc8921022e58d3843719d4ab821e
Reviewed-on: https://go-review.googlesource.com/83538
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
The package unsafe docs say it's safe to convert an unsafe.Pointer to
uintptr in the argument list to an assembly function, but it was
erroneously only detecting normal pointers converted to unsafe.Pointer
and then to intptr.
Fixes#23051.
Change-Id: Id1be19f6d8f26f2d17ba815191717d2f4f899732
Reviewed-on: https://go-review.googlesource.com/82817
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Pointer arithemetic is done mod 2^32 on 386, so we can just
drop the high bits of any large constant offsets.
The bounds check will make sure wraparounds are never observed.
Fixes#21655
Change-Id: I68ae5bbea9f02c73968ea2b21ca017e5ecb89223
Reviewed-on: https://go-review.googlesource.com/82675
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Make sure that when we're assigning to a map, we evaluate the
right-hand side before we attempt to insert into the map.
We used to evaluate the left-hand side to a pointer-to-slot-in-bucket
(which as a side effect does len(m)++), then evaluate the right-hand side,
then do the assignment. That clearly isn't correct when the right-hand side
might panic.
Fixes#22881
Change-Id: I42a62870ff4bf480568c9bdbf0bb18958962bdf0
Reviewed-on: https://go-review.googlesource.com/81817
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This test was added recently as a regress test for the spec relaxation
in #9060, but doesn't work correctly yet. Disable for now to fix noopt
builders.
Updates #22444.
Change-Id: I45c521ae0da7ffb0c6859d6f7220c59828ac6149
Reviewed-on: https://go-review.googlesource.com/81775
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The DWARF inline info generation hooks weren't properly
handling unused auto vars in certain cases, triggering an assert (now
fixed). Also with this change, introduce a new autom "flavor" to
use for autom entries that are added to insure that a specific
auto type makes it into the linker (this is a follow-on to the fix
for 22941).
Fixes#22962.
Change-Id: I7a2d8caf47f6ca897b12acb6a6de0eb25f5cac8f
Reviewed-on: https://go-review.googlesource.com/81557
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Per the decision for #14844, index expressions that are non-constant
shifts where the LHS operand is representable as an int are now valid.
Fixes#21693.
Change-Id: Ifafad2c0c65975e0200ce7e28d1db210e0eacd9d
Reviewed-on: https://go-review.googlesource.com/81277
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
The code that generates the list of DWARF variables for a function
(params and autos) will emit a "no-location" entry in the DWARF for a
user var that appears in the original pre-optimization version of the
function but is no longer around when optimization is complete. The
intent is that if a GDB user types "print foo" (where foo has been
optimized out), the response will be "<optimized out>" as opposed to
"there is no such variable 'foo'). This change fixes said code to
include vars on the autom list for the function, to insure that the
type symbol for the variable makes it to the linker.
Fixes#22941.
Change-Id: Id29f1f39d68fbb798602dfd6728603040624fc41
Reviewed-on: https://go-review.googlesource.com/81415
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
ORANGE node's Right node is the expression it is ranging over,
which is evaluated before the loop. In the escape analysis,
we should walk this node without loop depth incremented.
Fixes#21709.
Change-Id: Idc1e4c76e39afb5a344d85f6b497930a488ce5cf
Reviewed-on: https://go-review.googlesource.com/80740
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
For "type T = U" we were accidentally emitting a #define for "U__size"
instead of "T__size".
Fixes#22877.
Change-Id: I5ed6757d697753ed6d944077c16150759f6e1285
Reviewed-on: https://go-review.googlesource.com/80759
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The signature of the mapassign_fast* routines need to distinguish
the pointerness of their key argument. If the affected routines
suspend part way through, the object pointed to by the key might
get garbage collected because the key is typed as a uint{32,64}.
This is not a problem for mapaccess or mapdelete because the key
in those situations do not live beyond the call involved. If the
object referenced by the key is garbage collected prematurely, the
code still works fine. Even if that object is subsequently reallocated,
it can't be written to the map in time to affect the lookup/delete.
Fixes#22781
Change-Id: I0bbbc5e9883d5ce702faf4e655348be1191ee439
Reviewed-on: https://go-review.googlesource.com/79018
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
CL 76551 modified inline_callers.go to build everything, including the
runtime, with -l=4. While that works in most places (and ideally
should work everywhere), it blows out the nosplit stack on
solaris/amd64.
Fix this by only building the test itself with -l=4.
This undoes some of the changes to this test from CL 73212, which
originally changed the go tool to rebuild all packages with the given
flags. This change modified the expected output of this test, so now
that we can go back to building only the test itself with inlining, we
revert these changes to the expected output. (That CL also changed
log.Fatalf to log.Printf, but didn't add "\n" to the end of the lines,
so this CL fixes that, too.)
Fixes#22797.
Change-Id: I6a91963a59ebe98edbe0921d8717af6b2c2191b0
Reviewed-on: https://go-review.googlesource.com/79197
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Improve the error message for wrong
case-field names in composite literals,
by mentioning the correct field name.
Given the program:
package main
type it struct {
ID string
}
func main() {
i1 := &it{id: "Bar"}
}
just like we do for usage of fields, we now
report wrongly cased fields as hints to give:
ts.go:8:14: unknown field 'id' in struct literal of type it (but does have ID)
instead of before:
ts.go:8:14: unknown field 'id' in struct literal of type it
Fixes#22794
Change-Id: I18cd70e75817025cb1df083503cae306e8d659fd
Reviewed-on: https://go-review.googlesource.com/78545
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This test fails on 1.9.2, but is ok on tip.
CL 77331 has both the 1.9.2 fix and this test, and is on the 1.9 release branch.
This CL is just the test, and is on HEAD. The buggy code doesn't exist on tip.
Update #22683
Change-Id: I04a24bd6c2d3068e18ca81da3347e2c1366f4447
Reviewed-on: https://go-review.googlesource.com/77332
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Also, with this change, error locations don't print absolute positions
in [] brackets following positions relative to line directives. To get
the absolute positions as well, specify the -L flag.
Fixes#22660.
Change-Id: I9ecfa254f053defba9c802222874155fa12fee2c
Reviewed-on: https://go-review.googlesource.com/77090
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
It has always been problematic that there was no way to specify
tool flags that applied only to the build of certain packages;
it was only to specify flags for all packages being built.
The usual workaround was to install all dependencies of something,
then build just that one thing with different flags. Since the
dependencies appeared to be up-to-date, they were not rebuilt
with the different flags. The new content-based staleness
(up-to-date) checks see through this trick, because they detect
changes in flags. This forces us to address the underlying problem
of providing a way to specify per-package flags.
The solution is to allow -gcflags=pattern=flags, which means
that flags apply to packages matching pattern, in addition to the
usual -gcflags=flags, which is now redefined to apply only to
the packages named on the command line.
See #22527 for discussion and rationale.
Fixes#22527.
Change-Id: I6716bed69edc324767f707b5bbf3aaa90e8e7302
Reviewed-on: https://go-review.googlesource.com/76551
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Plain blocks that contain only uninteresting instructions
(that do not have reliable Pos information themselves)
need to have their Pos left unset so that they can
inherit it from their successors. The "uninteresting"
test was not properly applied and not properly defined.
OpFwdRef does not appear in the ssa.html debugging output,
but at the time of the test these instructions did appear,
and it needs to be part of the test.
Fixes#22365.
Change-Id: I99e5b271acd8f6bcfe0f72395f905c7744ea9a02
Reviewed-on: https://go-review.googlesource.com/74252
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
They could get picked up by reflect code, yielding the wrong type.
Fixes#22605
Change-Id: Ie11fb361ca7f3255e662037b3407565c8f0a2c4c
Reviewed-on: https://go-review.googlesource.com/76315
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Be more pessimistic when parsing if/switch/for headers for better error
messages when things go wrong.
Fixes#22581.
Change-Id: Ibb99925291ff53f35021bc0a59a4c9a7f695a194
Reviewed-on: https://go-review.googlesource.com/76290
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Updates #21317
@mdempsky fixed issue #21317 with CL 66810,
so lock a test in to ensure we don't regress.
The test is manual for now before test/run.go
has support for matching column numbers so do
it old school and match expected output after
an exec.
Change-Id: I6c2a66ddf04248f79d17ed7033a3280d50e41562
Reviewed-on: https://go-review.googlesource.com/76150
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Currently, assigning a []T where T is a go:notinheap type generates an
unnecessary write barrier for storing the slice pointer.
This fixes this by teaching HasHeapPointer that this type does not
have a heap pointer, and tweaking the lowering of slice assignments so
the pointer store retains the correct type rather than simply lowering
it to a *uint8 store.
Change-Id: I8bf7c66e64a7fefdd14f2bd0de8a5a3596340bab
Reviewed-on: https://go-review.googlesource.com/76027
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Updates #22389
@mdempsky's CL 70850 fixed the unnecessary
compile stack trace printing during ICE diagnostics.
This CL adds a test to lock in this behavior.
Change-Id: I9ce49923c80b78cb8c0bb5dc4af3c860a43d63ba
Reviewed-on: https://go-review.googlesource.com/74630
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
CL 65071 enabled inlining for local closures with no captures.
To determine safety of inlining a call sites, we check whether the
variable holding the closure has any assignments after its original
definition.
Unfortunately, that check did not catch OAS2MAPR and OAS2DOTTYPE,
leading to incorrect inlining when a variable holding a closure was
subsequently reassigned through a type conversion or a 2-valued map
access.
There was another more subtle issue wherein reassignment check would
always return a false positive for closure calls inside other
closures. This was caused by the Name.Curfn field of local variables
pointing to the OCLOSURE node instead of the corresponding ODCLFUNC,
which resulted in reassigned walking an empty Nbody and thus never
seeing any reassignments.
This CL fixes these oversights and adds many more tests for closure
inlining which ensure not only that inlining triggers but also the
correctness of the resulting code.
Updates #15561
Change-Id: I74bdae849c4ecfa328546d6d62b512e8d54d04ce
Reviewed-on: https://go-review.googlesource.com/75770
Reviewed-by: Hugues Bruant <hugues.bruant@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Instead of trying to validate map key types eagerly in some
cases, delay their validation to the end of type-checking,
when we all type information is present.
Passes go build -toolexec 'toolstash -cmp' -a std .
Fixes#21273.
Fixes#21657.
Change-Id: I532369dc91c6adca1502d6aa456bb06b57e6c7ff
Reviewed-on: https://go-review.googlesource.com/75310
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Handle make(map[any]any) and make(map[any]any, hint) where
hint <= BUCKETSIZE special to allow for faster map initialization
and to improve binary size by using runtime calls with fewer arguments.
Given hint is smaller or equal to BUCKETSIZE in which case
overLoadFactor(hint, 0) is false and no buckets would be allocated by makemap:
* If hmap needs to be allocated on the stack then only hmap's hash0
field needs to be initialized and no call to makemap is needed.
* If hmap needs to be allocated on the heap then a new special
makehmap function will allocate hmap and intialize hmap's
hash0 field.
Reduces size of the godoc by ~36kb.
AMD64
name old time/op new time/op delta
NewEmptyMap 16.6ns ± 2% 5.5ns ± 2% -66.72% (p=0.000 n=10+10)
NewSmallMap 64.8ns ± 1% 56.5ns ± 1% -12.75% (p=0.000 n=9+10)
Updates #6853
Change-Id: I624e90da6775afaa061178e95db8aca674f44e9b
Reviewed-on: https://go-review.googlesource.com/61190
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
The test was skipped because it did not work on AMD64 with
frame pointer enabled, and accidentally skipped on other
architectures. Now frame pointer is the default on AMD64.
Update the test to work with frame pointer. Now the test
is skipped only when frame pointer is NOT enabled on AMD64.
Fixes#18317.
Change-Id: I724cb6874e562f16e67ce5f389a1d032a2003115
Reviewed-on: https://go-review.googlesource.com/68610
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
This cuts 6 seconds off all.bash with the new go command.
Not a ton, but also an easy 6 seconds to grab.
The -tags=use_go_run in the misc/cgo tests is just some
go command flag that will make run.go use go run,
but without making everything look stale.
(Those tests have relative imports,
so go tool compile+link is not enough.)
Change-Id: I43bf4bb661d3adde2b2d4aad5e8f64b97bc69ba9
Reviewed-on: https://go-review.googlesource.com/73994
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This CL changes the go command to base all its rebuilding decisions
on the content of the files being processed and not their file system
modification times. It also eliminates the special handling of release
toolchains, which were previously considered always up-to-date
because modification time order could not be trusted when unpacking
a pre-built release.
The go command previously tracked "build IDs" as a backup to
modification times, to catch changes not reflected in modification times.
For example, if you remove one .go file in a package with multiple .go
files, there is no modification time remaining in the system that indicates
that the installed package is out of date. The old build ID was the hash
of a list of file names and a few other factors, expected to change if
those factors changed.
This CL moves to using this kind of build ID as the only way to
detect staleness, making sure that the build ID hash includes all
possible factors that need to influence the rebuild decision.
One such factor is the compiler flags. As of this CL, if you run
go build -gcflags -N cmd/gofmt
you will get a gofmt where every package is built with -N,
regardless of what may or may not be installed already.
Another such factor is the linker flags. As of this CL, if you run
go install myprog
go install -ldflags=-s myprog
the second go install will now correctly build a new myprog with
the updated linker flags. (Previously the installed myprog appeared
up-to-date, because the ldflags were not included in the build ID.)
Because we have more precise information we can also validate whether
the target of a "go test -c" operation is already the right binary and
therefore can avoid a rebuild.
This CL sets us up for having a more general build artifact cache,
maybe even a step toward not having a pkg directory with .a files,
but this CL does not take that step. For now the result of go install
is the same as it ever was; we just do a better job of what needs to
be installed.
This CL does slow down builds a small amount by reading all the
dependent source files in full. (The go command already read the
beginning of every dependent source file to discover build tags
and imports.) On my MacBook Pro, before this CL all.bash takes
3m58s, while after this CL and a few optimizations stacked above it
all.bash takes 4m28s. Given that CL 73850 cut 1m43s off the all.bash
time earlier today, we can afford adding 30s back for now.
More optimizations are planned that should make the go command
more efficient than it was even before this CL.
Fixes#15799.
Fixes#18369.
Fixes#19340.
Fixes#21477.
Change-Id: I10d7ca0e31ca3f58aabb9b1f11e2e3d9d18f0bc9
Reviewed-on: https://go-review.googlesource.com/73212
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
If the go install doesn't use the same flags as the main build
it can overwrite the installed standard library, leading to
flakiness and slow future tests.
Force uses of 'go install' etc to propagate $GO_GCFLAGS
or disable them entirely, to avoid problems.
As I understand it, the main place this happens is the ssacheck builder.
If there are other uses that need to run some of the now-disabled
tests we can reenable fixed tests in followup CLs.
Change-Id: Ib860a253539f402f8a96a3c00ec34f0bbf137c9a
Reviewed-on: https://go-review.googlesource.com/74470
Reviewed-by: David Crawshaw <crawshaw@golang.org>
The test for #18902 reads the assembly stream to be sure
that the line number does not change too often (this is an
indication that debugging the code will be unpleasant and
that the compiler is probably getting line numbers "wrong").
It checks that it is getting "enough" input, but the
compiler has gotten enough better since the test was written
that it now fails for lack of enough input. The old
threshould was 200 instructions, the new one is 150 (the
minimum observed input is on arm64 with 184 instructions).
Fixes#22494.
Change-Id: Ibba7e9ff4ab6a7be369e5dd5859d150b7db94653
Reviewed-on: https://go-review.googlesource.com/74357
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
KeepAlive needs to introduce a use of the spill of the
value it is keeping alive. Without that, we don't guarantee
that the spill dominates the KeepAlive.
This bug was probably introduced with the code to move spills
down to the dominator of the restores, instead of always spilling
just after the value itself (CL 34822).
Fixes#22458.
Change-Id: I94955a21960448ffdacc4df775fe1213967b1d4c
Reviewed-on: https://go-review.googlesource.com/74210
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
Currently copy and append for types containing only scalars and
notinheap pointers still get compiled to have write barriers, even
though those write barriers are unnecessary. Fix these to use
HasHeapPointer instead of just Haspointer so that they elide write
barriers when possible.
This fixes the unnecessary write barrier in runtime.recordspan when it
grows the h.allspans slice. This is important because recordspan gets
called (*very* indirectly) from (*gcWork).tryGet, which is
go:nowritebarrierrec. Unfortunately, the compiler's analysis has no
hope of seeing this because it goes through the indirect call
fixalloc.first, but I saw it happen.
Change-Id: Ieba3abc555a45f573705eab780debcfe5c4f5dd1
Reviewed-on: https://go-review.googlesource.com/73413
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Currently (*Type).HasHeapPointer only ignores pointers go:notinheap
types if the type itself is a pointer to a go:notinheap type. However,
if it's some other type that contains pointers where all of those
pointers are go:notinheap, it will conservatively return true. As a
result, we'll use write barriers where they aren't needed, for example
calling typedmemmove instead of just memmove on structs that contain
only go:notinheap pointers.
Fix this by making HasHeapPointer walk the whole type looking for
pointers that aren't marked go:notinheap.
Change-Id: Ib8c6abf6f7a20f34969d1d402c5498e0b990be59
Reviewed-on: https://go-review.googlesource.com/73412
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
The current go:nowritebarrierrec checker has two problems that limit
its coverage:
1. It doesn't understand that systemstack calls its argument, which
means there are several cases where we fail to detect prohibited write
barriers.
2. It only observes calls in the AST, so calls constructed during
lowering by SSA aren't followed.
This CL completely rewrites this checker to address these issues.
The current checker runs entirely after walk and uses visitBottomUp,
which introduces several problems for checking across systemstack.
First, visitBottomUp itself doesn't understand systemstack calls, so
the callee may be ordered after the caller, causing the checker to
fail to propagate constraints. Second, many systemstack calls are
passed a closure, which is quite difficult to resolve back to the
function definition after transformclosure and walk have run. Third,
visitBottomUp works exclusively on the AST, so it can't observe calls
created by SSA.
To address these problems, this commit splits the check into two
phases and rewrites it to use a call graph generated during SSA
lowering. The first phase runs before transformclosure/walk and simply
records systemstack arguments when they're easy to get. Then, it
modifies genssa to record static call edges at the point where we're
lowering to Progs (which is the latest point at which position
information is conveniently available). Finally, the second phase runs
after all functions have been lowered and uses a direct BFS walk of
the call graph (combining systemstack calls with static calls) to find
prohibited write barriers and construct nice error messages.
Fixes#22384.
For #22460.
Change-Id: I39668f7f2366ab3c1ab1a71eaf25484d25349540
Reviewed-on: https://go-review.googlesource.com/72773
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
...because that's an illegal addressing mode.
I double-checked handling of this code, and 387 is the only
place where this check is missing.
Fixes#22429
Change-Id: I2284fe729ea86251c6af2f04076ddf7a5e66367c
Reviewed-on: https://go-review.googlesource.com/73551
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
If n.Type==nil after typechecking, then we should have already
reported a more useful error somewhere else. Just return 0 in
evalunsafe without trying to do anything else that's likely to cause
problems.
Also, further split out issue7525.go into more test files, because
cmd/compile reports at most one typechecking loop per compilation
unit.
Fixes#22351.
Change-Id: I3ebf505f72c48fcbfef5ec915606224406026597
Reviewed-on: https://go-review.googlesource.com/72251
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Robert Griesemer <gri@golang.org>
Fine-tune skipping of tokens after missing closing parentheses in lists.
Fixes#22164.
Change-Id: I575d86e21048cd40340a2c08399e8b0deec337cf
Reviewed-on: https://go-review.googlesource.com/71250
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Follow CL 41477 and add two more line position tests for yyerror calls
in the typechecker which are currently not tested.
Update #19683
Change-Id: Iacd865195a3bfba87d8c22655382af267aba47a9
Reviewed-on: https://go-review.googlesource.com/70251
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Previously, we were treating cross-package function calls as free for
inlining budgeting.
In theory, we should be able to recompute InlCost from the
exported/reimported function bodies. However, that process mutates the
structure of the Node AST enough that it doesn't preserve InlCost. To
avoid unexpected issues, just record and restore InlCost in the export
data.
Fixes#19261.
Change-Id: Iac2bc0d32d4f948b64524aca657051f9fc96d92d
Reviewed-on: https://go-review.googlesource.com/70151
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
Calls to a closure held in a local, non-escaping,
variable can be inlined, provided the closure body
can be inlined and the variable is never written to.
The current implementation has the following limitations:
- closures with captured variables are not inlined because
doing so naively triggers invariant violation in the SSA
phase
- re-assignment check is currently approximated by checking
the Addrtaken property of the variable which should be safe
but may miss optimization opportunities if the address is
not used for a write before the invocation
Updates #15561
Change-Id: I508cad5d28f027bd7e933b1f793c14dcfef8b5a1
Reviewed-on: https://go-review.googlesource.com/65071
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Hugues Bruant <hugues.bruant@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
It should be skipped on 32-bit architectures.
Change-Id: If7a64b9e90e47c3e8734dd62729bfd2944ae926c
Reviewed-on: https://go-review.googlesource.com/70071
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
If the stack frame is too large, abort immediately.
We used to generate code first, then abort.
In issue 22200, generating code raised a panic
so we got an ICE instead of an error message.
Change the max frame size to 1GB (from 2GB).
Stack frames between 1.1GB and 2GB didn't used to work anyway,
the pcln table generation would have failed and generated an ICE.
Fixes#22200
Change-Id: I1d918ab27ba6ebf5c87ec65d1bccf973f8c8541e
Reviewed-on: https://go-review.googlesource.com/69810
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This re-enables functionality that inadvertently was disabled in the
(long) past.
Also, don't perform branch checks if we had errors in a function
to avoid spurious errors or (worst-case) crashes.
Slightly modified test/fixedbugs/issue14006.go to make sure the
test still reports invalid label errors (the surrounding function
must be syntactically correct).
Change-Id: Id5642930877d7cf3400649094ec75c753b5084b7
Reviewed-on: https://go-review.googlesource.com/69770
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
We've supported inlining methods called as functions for a while now.
Change-Id: I53fba426e45f91d65a38f00456c2ae1527372b50
Reviewed-on: https://go-review.googlesource.com/69530
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Keep left-to-right order when referring to the number of
variables and values involved.
Fixes#22159.
Change-Id: Iccca12d3222f9d5e049939a9ccec07513c393faa
Reviewed-on: https://go-review.googlesource.com/68690
Reviewed-by: Russ Cox <rsc@golang.org>
C_PPAUTO was matching offsets that is a multiple 8. But this
condition is dropped in CL 55610, causing unaligned offset
between 256 and 504 mistakenly matched to some classes, e.g.
C_UAUTO8K. This CL restores this condition, also fixes an
error that C_PPAUTO shouldn't match C_PSAUTO, because the
latter is not guaranteed to be multiple of 8. C_PPAUTO_8 is
unnecessary, removed.
Fixes#21992.
Change-Id: I75d5a0e5f5dc3dae335721fbec1bbcd4a3b862f2
Reviewed-on: https://go-review.googlesource.com/65730
Reviewed-by: David Chase <drchase@google.com>
