prove is able to find 94 occurrences in std cmd where a divisor
can't have the value -1. The change removes
the extraneous fix-up code for these cases.
Fixes#25239
Change-Id: Ic184de971f47cc57c702eb72805b8e291c14035d
Reviewed-on: https://go-review.googlesource.com/c/130215
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
The second and subsequent return values from f() need to be
converted to the element type of the first return value from f()
(which must be a slice).
Fixes#22327
Change-Id: I5c0a424812c82c1b95b6d124c5626cfc4408bdb6
Reviewed-on: https://go-review.googlesource.com/c/142718
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This CL add 3 rules to combine byte-store to word-store on386 and
amd64.
Change-Id: Iffd9cda42f1961680c81def4edc773ad58f211b3
Reviewed-on: https://go-review.googlesource.com/c/143057
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
As of https://golang.org/cl/43456 gccgo now gives a better error
message for this test.
Before:
fixedbugs/issue5089.go:13:1: error: redefinition of ‘bufio.Buffered’: receiver name changed
func (b *bufio.Reader) Buffered() int { // ERROR "non-local|redefinition"
^
fixedbugs/issue5089.go:11:13: note: previous definition of ‘bufio.Buffered’ was here
import "bufio" // GCCGO_ERROR "previous"
^
Now:
fixedbugs/issue5089.go:13:7: error: may not define methods on non-local type
func (b *bufio.Reader) Buffered() int { // ERROR "non-local|redefinition"
^
Change-Id: I4112ca8d91336f6369f780c1d45b8915b5e8e235
Reviewed-on: https://go-review.googlesource.com/c/130955
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Building with gccgo failed with an undefined symbol error from an
unnecessary hash function.
Updates #19773
Change-Id: Ic78bf1b086ff5ee26d464089c0e14987d3fe8b02
Reviewed-on: https://go-review.googlesource.com/c/130956
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This CL adds more combined load/store test cases for 386/amd64.
Change-Id: I0a483a6ed0212b65c5e84d67ed8c9f50c389ce2d
Reviewed-on: https://go-review.googlesource.com/c/142878
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Nowadays there are better ways to safely run untrusted Go programs, like
NaCl and gVisor.
Change-Id: I20c45f13a50dbcf35c343438b720eb93e7b4e13a
Reviewed-on: https://go-review.googlesource.com/c/142717
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
This appears to have simply been an oversight.
Change-Id: Ia5d1309b3ebc99c9abbf0282397693272d8178aa
Reviewed-on: https://go-review.googlesource.com/c/142885
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Ensure that label redefinition error column numbers
print the actual start of the label instead of the
position of the label's delimiting token ":".
For example, given this program:
package main
func main() {
foo:
foo:
foo:
foo :
}
* Before:
main.go:5:13: label foo defined and not used
main.go:6:7: label foo already defined at main.go:5:13
main.go:7:4: label foo already defined at main.go:5:13
main.go:8:16: label foo already defined at main.go:5:13
* After:
main.go:5:13: label foo defined and not used
main.go:6:4: label foo already defined at main.go:5:13
main.go:7:1: label foo already defined at main.go:5:13
main.go:8:1: label foo already defined at main.go:5:13
Fixes#26411
Change-Id: I8eb874b97fdc8862547176d57ac2fa0f075f2367
Reviewed-on: https://go-review.googlesource.com/c/124595
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Numbers without decimals are valid Go representations of whole-number
floats. That is, "var x float64 = 5" is valid Go. Avoid breakage in
tests that expect a certain output from %#v by reverting to it.
To guarantee the right type is generated by a print use %T(%#v) instead.
Added a test to lock in this behavior.
This reverts commit 7c7cecc184.
Fixes#27634
Updates #26363
Change-Id: I544c400a0903777dd216452a7e86dfe60b0b0283
Reviewed-on: https://go-review.googlesource.com/c/142597
Run-TryBot: Filippo Valsorda <filippo@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
ARMv7's MULAF/MULSF/MULAD/MULSD are not fused,
this CL fixes the confusing test cases.
Change-Id: I35022e207e2f0d24a23a7f6f188e41ba8eee9886
Reviewed-on: https://go-review.googlesource.com/c/142439
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Akhil Indurti <aindurti@gmail.com>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
In golang.org/cl/75310, the compiler's typechecker was changed so that
map key types were validated at a later stage, to make sure that all the
necessary type information was present.
This still worked for map type declarations, but caused a regression for
top-level map variable declarations. These now caused a fatal panic
instead of a typechecking error.
The cause was that checkMapKeys was run too early, before all
typechecking was done. In particular, top-level map variable
declarations are typechecked as external declarations, much later than
where checkMapKeys was run.
Add a test case for both exported and unexported top-level map
declarations, and add a second call to checkMapKeys at the actual end of
typechecking. Simply moving the one call isn't a good solution either;
the comments expand on that.
Fixes#28058.
Change-Id: Ia5febb01a1d877447cf66ba44fb49a7e0f4f18a5
Reviewed-on: https://go-review.googlesource.com/c/140417
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
x = map[string(byteslice)] is already optimized by the compiler to avoid a
string allocation. This CL generalizes this optimization to:
x = map[T1{ ... Tn{..., string(byteslice), ...} ... }]
where T1 to Tn is a nesting of struct and array literals.
Found in a hot code path that used a struct of strings made from []byte
slices to make a map lookup.
There are no uses of the more generalized optimization in the standard library.
Passes toolstash -cmp.
MapStringConversion/32/simple 21.9ns ± 2% 21.9ns ± 3% ~ (p=0.995 n=17+20)
MapStringConversion/32/struct 28.8ns ± 3% 22.0ns ± 2% -23.80% (p=0.000 n=20+20)
MapStringConversion/32/array 28.5ns ± 2% 21.9ns ± 2% -23.14% (p=0.000 n=19+16)
MapStringConversion/64/simple 21.0ns ± 2% 21.1ns ± 3% ~ (p=0.072 n=19+18)
MapStringConversion/64/struct 72.4ns ± 3% 21.3ns ± 2% -70.53% (p=0.000 n=20+20)
MapStringConversion/64/array 72.8ns ± 1% 21.0ns ± 2% -71.13% (p=0.000 n=17+19)
name old allocs/op new allocs/op delta
MapStringConversion/32/simple 0.00 0.00 ~ (all equal)
MapStringConversion/32/struct 0.00 0.00 ~ (all equal)
MapStringConversion/32/array 0.00 0.00 ~ (all equal)
MapStringConversion/64/simple 0.00 0.00 ~ (all equal)
MapStringConversion/64/struct 1.00 ± 0% 0.00 -100.00% (p=0.000 n=20+20)
MapStringConversion/64/array 1.00 ± 0% 0.00 -100.00% (p=0.000 n=20+20)
Change-Id: I483b4d84d8d74b1025b62c954da9a365e79b7a3a
Reviewed-on: https://go-review.googlesource.com/c/116275
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This change adds codegen tests for the intrinsification on ppc64 of
the OnesCount{64,32,16,8}, and TrailingZeros{64,32,16,8} math/bits
functions.
Change-Id: Id3364921fbd18316850e15c8c71330c906187fdb
Reviewed-on: https://go-review.googlesource.com/c/141897
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Ensure that we correctly type the stack temps for regular closures,
method function closures, and slice literals.
Then we don't need to override the dummy types later.
Furthermore, this allows order to reuse temporaries of these types.
OARRAYLIT doesn't need a temporary as far as I can tell, so I
removed that case from order.
Change-Id: Ic58520fa50c90639393ff78f33d3c831d5c4acb9
Reviewed-on: https://go-review.googlesource.com/c/140306
Reviewed-by: Cherry Zhang <cherryyz@google.com>
This CL adds tests of fused multiplication-accumulation
on arm/arm64.
Change-Id: Ic85d5277c0d6acb7e1e723653372dfaf96824a39
Reviewed-on: https://go-review.googlesource.com/c/141652
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
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>
