When we remove a nil check, add it back to the free Value pool immediately.
Fixes#18732
Change-Id: I8d644faabbfb52157d3f2d071150ff0342ac28dc
Reviewed-on: https://go-review.googlesource.com/58810
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
CL 54410 and CL 56250 recently added use of the MOVOstore
instruction to improve performance.
However, we can't use the MOVOstore instruction on Plan 9,
because floating point operations are not allowed in the
note handler.
This change adds a configuration flag useSSE to enable the
use of SSE instructions for non-floating point operations.
This flag is enabled by default and disabled on Plan 9.
When this flag is disabled, the MOVOstore instruction is
not used and the MOVQstoreconst instruction is used instead.
Fixes#21599
Change-Id: Ie609e5d9b82ec0092ae874bab4ce01caa5bc8fb8
Reviewed-on: https://go-review.googlesource.com/58850
Reviewed-by: Keith Randall <khr@golang.org>
For code like the following (where x escapes):
x := []int{1}
We're currently generating a nil check. The line above is really 3 operations:
t := new([1]int)
t[0] = 1
x := t[:]
We remove the nil check for t[0] = 1, but not for t[:].
Our current nil check removal rule is too strict about the possible
memory arguments of the nil check. Unlike zeroing or storing to the
result of runtime.newobject, the nilness of runtime.newobject is
always false, even after other stores have happened in the meantime.
Change-Id: I95fad4e3a59c27effdb37c43ea215e18f30b1e5f
Reviewed-on: https://go-review.googlesource.com/58711
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
In writelines the linker uses various auxiliary information about a
function to create its line table entries. (It also does some unrelated
stuff, but never mind.) There's no reason to do this for non-Go
functions, so it bails out if the symbol has no FuncInfo.
However, it does so *after* it looks up (and implicitly creates!) the
go.info symbol for the function, which doesn't make sense and risks
creating duplicate symbols for static C functions. Move the check up so
that it doesn't do that.
Since non-Go functions can't reference Go types, there shouldn't be any
relocations to type info DIEs that need to be built, so there should be
no harm not doing that.
I wanted to change the Lookup to an ROLookup but that broke the
shared-mode tests with an inscrutable error.
No test. It seems too specific to worry about, but if someone disagrees
I can figure something out.
Fixes#21566
Change-Id: I61f03b7c504a3bf1c4245a8811795b6303469e91
Reviewed-on: https://go-review.googlesource.com/58630
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Otherwise the default computation in symalign kicked in, setting the
alignment to be too high. This didn't matter with GNU ld, which put
each loadable note into a separate PT_NOTE segment, but it did matter
with gold which accumulated them all into a single PT_NOTE segment,
respecting the requested alignment. In the single PT_NOTE segment
generated by gold, the incorrect section alignment made the notes
unreadable.
Fixes#21564
Change-Id: I15eb408bb04a2566c9fdfb6828e14188d9ef2280
Reviewed-on: https://go-review.googlesource.com/58290
Reviewed-by: Russ Cox <rsc@golang.org>
This is a crude compiler pass to eliminate stores to auto variables
that are only ever written to.
Eliminates an unnecessary store to x from the following code:
func f() int {
var x := 1
return *(&x)
}
Fixes#19765.
Change-Id: If2c63a8ae67b8c590b6e0cc98a9610939a3eeffa
Reviewed-on: https://go-review.googlesource.com/38746
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
This prevents unnecessary reg-reg moves during pointer arithmetic.
This change reduces the size of the full hello world binary by 0.4%.
Updates #21572
Change-Id: Ia0427021e5c94545a0dbd83a6801815806e5b12d
Reviewed-on: https://go-review.googlesource.com/58371
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Run "cmd/go terminal test" after standard library tests.
Run "testing race detector" before cgo tests, not in the middle of them.
Fixes#21524
Change-Id: I32964ec6377dd070242138ec452bd8ab1821dcc5
Reviewed-on: https://go-review.googlesource.com/57230
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Joe Tsai <joetsai@google.com>
The current code treats floating-point constant as integer
and does not treat fcmp/fcmpe as the comparison instrucitons
that requires special handling.
The fix corrects the type of immediate arguments and adds fcmp/fcmpe
in the special handing.
Uncomment the fcmp/fcmpe cases.
Fixes#21567
Change-Id: I6782520e2770f6ce70270b667dd5e68f71e2d5ad
Reviewed-on: https://go-review.googlesource.com/57852
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
mkcall is used to construct calls to builtin functions.
Instead of silently ignoring any additional arguments to mkcall
abort compilation with an error.
This protects against accidentally supplying too many arguments to mkcall
when compiler changes are made.
Change appendslice and copyany to construct calls to
slicestringcopy and slicecopy explicitly instead of
relying on the old behavior as a feature.
Change-Id: I3cfe815a57d454a129e3c08aac824f6107779a42
Reviewed-on: https://go-review.googlesource.com/57770
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Where possible generate calls to runtime makemap with int hint argument
during compile time instead of makemap with int64 hint argument.
This eliminates converting the hint argument for calls to makemap with
int64 hint argument for platforms where int64 values do not fit into
an argument of type int.
A similar optimization for makeslice was introduced in CL
golang.org/cl/27851.
386:
name old time/op new time/op delta
NewEmptyMap 53.5ns ± 5% 41.9ns ± 5% -21.56% (p=0.000 n=10+10)
NewSmallMap 182ns ± 1% 165ns ± 1% -8.92% (p=0.000 n=10+10)
Change-Id: Ibd2b4c57b36f171b173bf7a0602b3a59771e6e44
Reviewed-on: https://go-review.googlesource.com/55142
Reviewed-by: Keith Randall <khr@golang.org>
This change adds to the code-generation harness in asm_test.go support
for the use of a '$' placeholder name for test functions.
A few of uninformative function names are also changed to use the
placeholder, to confirm that the change works as expected.
Fixes#21500
Change-Id: Iba168bd85efc9822253305d003b06682cf8a6c5c
Reviewed-on: https://go-review.googlesource.com/57292
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Some debuggers use the declaration line to avoid showing variables
before they're declared. Emit them for local variables and function
parameters.
DW_AT_decl_file would be nice too, but since its value is an index
into a table built by the linker, that's dramatically harder. In
practice, with inlining disabled it's safe to assume that all a
function's variables are declared in the same file, so this should still
be pretty useful.
Change-Id: I8105818c8940cd71bc5473ec98797cce2f3f9872
Reviewed-on: https://go-review.googlesource.com/44350
Reviewed-by: David Chase <drchase@google.com>
eqstring is only called for strings with equal lengths.
Instead of pushing a pointer and length for each argument string
on the stack we can omit pushing one of the lengths on the stack.
Changing eqstrings signature to eqstring(*uint8, *uint8, int) bool
to implement the above optimization would make it very similar to the
existing memequal(*any, *any, uintptr) bool function.
Since string lengths are positive we can avoid code redundancy and
use memequal instead of using eqstring with an optimized signature.
go command binary size reduced by 4128 bytes on amd64.
name old time/op new time/op delta
CompareStringEqual 6.03ns ± 1% 5.71ns ± 1% -5.23% (p=0.000 n=19+18)
CompareStringIdentical 2.88ns ± 1% 3.22ns ± 7% +11.86% (p=0.000 n=20+20)
CompareStringSameLength 4.31ns ± 1% 4.01ns ± 1% -7.17% (p=0.000 n=19+19)
CompareStringDifferentLength 0.29ns ± 2% 0.29ns ± 2% ~ (p=1.000 n=20+20)
CompareStringBigUnaligned 64.3µs ± 2% 64.1µs ± 3% ~ (p=0.164 n=20+19)
CompareStringBig 61.9µs ± 1% 61.6µs ± 2% -0.46% (p=0.033 n=20+19)
Change-Id: Ice15f3b937c981f0d3bc8479a9ea0d10658ac8df
Reviewed-on: https://go-review.googlesource.com/53650
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
If an error was already printed during LHS conversion step, we don't reprint
the "cannot convert" error.
In particular, this prevents `_ = int("1")` (and all similar casts) from
resulting in multiple identical error messages being printed.
Fixes#20812.
Change-Id: If6e52c59eab438599d641ecf6f110ebafca740a9
Reviewed-on: https://go-review.googlesource.com/46912
Reviewed-by: Robert Griesemer <gri@golang.org>
The current code gets shift arguments value from prog.From3.Offset.
But prog.From3.Offset is not assigned the shift arguments value in
instructions assemble process.
The fix calls movcon() function to get the correct value.
Uncomment the movk/movkw cases.
Fixes#21398
Change-Id: I78d40c33c24bd4e3688a04622e4af7ddb5333fa6
Reviewed-on: https://go-review.googlesource.com/54990
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
BFX extracts given bits from the source register, sign extends them
to 32-bit, and writes to destination register. BFXU does the similar
operation with zero extention.
They were introduced in ARMv6T2.
Change-Id: I6822ebf663497a87a662d3645eddd7c611de2b1e
Reviewed-on: https://go-review.googlesource.com/56071
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
On arm64, all boolean-generating instructions (CSET, etc.) set the upper
63 bits of the destination register to zero, so there is no need
to zero-extend the lower 8 bits again.
Fixes#21445
Change-Id: I3b176baab706eb684105400bacbaa24175f721f3
Reviewed-on: https://go-review.googlesource.com/55671
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
The go tool assumed that -buildmode=pie implied internal linking on
linux-amd64. However, that was changed by CL 36417 for issue #18968.
Fixes#21452
Change-Id: I8ed13aea52959cc5c53223f4c41ba35329445545
Reviewed-on: https://go-review.googlesource.com/57231
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Avelino <t@avelino.xxx>
Reviewed-by: Rob Pike <r@golang.org>
We can add a constant to loaction in memory with 1 instruction,
as opposed to load+add+store, so add a new op and relevent ssa rules.
Triggers in e. g. encoding/json isValidNumber:
NumberIsValid-6 36.4ns ± 0% 35.2ns ± 1% -3.32% (p=0.000 n=6+10)
Shaves ~2.5 kb from go tool.
Change-Id: I7ba576676c2522432360f77b290cecb9574a93c3
Reviewed-on: https://go-review.googlesource.com/54431
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
All of these are uints of different sizes, so checking >= 0 or < 0 are
effectively no-ops.
Found with staticcheck.
Change-Id: I16ac900eb7007bc8f9018b302136d42e483a4180
Reviewed-on: https://go-review.googlesource.com/56950
Reviewed-by: Matt Layher <mdlayher@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Matt Layher <mdlayher@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Normally 64-bit div/mod is turned into runtime calls on 32-bit
arch, but the front end leaves power-of-two constant division
and hopes the SSA backend turns into a shift or AND. The SSA rule is
(Mod64u <t> n (Const64 [c])) && isPowerOfTwo(c) -> (And64 n (Const64 <t> [c-1]))
But isPowerOfTwo returns true only for positive int64, which leaves
out 1<<63 unhandled. Add a special case for 1<<63.
Fixes#21517.
Change-Id: I02d27dc7177d4af0ee8d7f5533714edecddf8c95
Reviewed-on: https://go-review.googlesource.com/56890
Reviewed-by: Keith Randall <khr@golang.org>
Instructions added in https://golang.org/cl/18853
2nd change out of 3 to cover AMD64 SSSE3 instruction set in Go asm.
This commit does not actually add any new instructions, only
enables some test cases.
Change-Id: I9596435b31ee4c19460a51dd6cea4530aac9d198
Reviewed-on: https://go-review.googlesource.com/56835
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
Package.Internal.Imports is enough in nearly all cases,
and not maintaining a separate Package.Internal.Deps
avoids the two lists ending up out of sync.
(In some synthesized packages created during go test,
only Internal.Imports is initialized.)
Change-Id: I83f6a3ec6e6cbd75382f1fa0e439d31feec32d5a
Reviewed-on: https://go-review.googlesource.com/56278
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Before it was obj, but if you don't have everything paged in
that sounds a bit like an object file. Use objdir, which is more
clearly a directory and also matches the Action.Objdir struct field.
Change-Id: I268042800f9ca05721814d7f18c728acb4831232
Reviewed-on: https://go-review.googlesource.com/56277
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Update BinaryOnly test by adding import _ "fmt".
Change-Id: I3a1dcfb83a27d8ff50a658060a46e1a3f481f6c7
Reviewed-on: https://go-review.googlesource.com/56276
Reviewed-by: Ian Lance Taylor <iant@golang.org>
ImportPaths is also the name of a top-level function.
It is confusing to have a capitalized local variable.
Change-Id: I1313e05ade4934d4ee250a67e5af6d1bd6229aca
Reviewed-on: https://go-review.googlesource.com/56275
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Now that we have t.Helper, might as well use it to make the
reported failure lines more helpful.
Change-Id: I2a0c64e9ca7bdc0eaf2b62f9f855c41467767084
Reviewed-on: https://go-review.googlesource.com/56274
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>
When we make the go command pay attention to content
instead of time, we want this test to continue working.
Change-Id: Ib7d9d0d62bfe87810d71bdfc4f29561a8c70eccc
Reviewed-on: https://go-review.googlesource.com/56273
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Using a fake CC fails today if runtime/cgo is stale, because the
build will try to rebuild runtime/cgo using the fake CC, and the
fake CC is not a working C compiler.
Worse, in the future, when the go command is sensitive to details like
the fact that different CCs produce different outputs, putting in
the fake CC will make runtime/cgo look stale even if it was
formerly up-to-date.
Fix both problems by not overriding CC and instead looking at
the command being run to make sure the flags are quoted as expected.
Change-Id: I4417e35cfab33a07546cc90748ddb6119d8fdb2d
Reviewed-on: https://go-review.googlesource.com/56272
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This makes the construction of pmain.Internal.Imports consistently ordered.
Change-Id: I82348a18c7824378aa7e5bc5b6bcd550d4b758da
Reviewed-on: https://go-review.googlesource.com/56271
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Change-Id: I7f7b1e7ef832d53a93562b08ae914d023247c2c0
Reviewed-on: https://go-review.googlesource.com/56312
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Just to get rid of lots of .Name() stutter in printf calls.
Change-Id: I86cf00b3f7b2172387a1c6a7f189c1897fab6300
Reviewed-on: https://go-review.googlesource.com/56630
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Fix a missed change from:
https://golang.org/cl/56190
pointed out on the fossil mailing list shortly after submission
of the change mentioned above. See:
http://www.mail-archive.com/fossil-users@lists.fossil-scm.org/msg25736.html
This change adds fossil to the general regular expression that is checked last
in the import path check.
For #10010
Change-Id: I6b711cdb1a8d4d767f61e1e28dc29dce529e0fad
Reviewed-on: https://go-review.googlesource.com/56491
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
We already combine const stores up-to MOVQstoreconst.
Combine 2 64-bit stores of const zero into 1 sse store of 128-bit zero.
Shaves significant (>1%) amount of code from go tool:
/localdisk/itocar/golang/bin/go 10334877
go_old 10388125 [53248 bytes]
global text (code) = 51041 bytes (1.343944%)
read-only data = 663 bytes (0.039617%)
Total difference 51704 bytes (0.873981%)
Change-Id: I7bc40968023c3a69f379b10fbb433cdb11364f1b
Reviewed-on: https://go-review.googlesource.com/56250
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Reviewed-by: Keith Randall <khr@golang.org>
Instructions are implemented in the following revisions:
PCMPESTRI - https://golang.org/cl/22337
PHMINPOSUW - https://golang.org/cl/18853
It is unknown when x86test will be updated/re-run, but tests are useful
to check which x86 instructions are not yet supported.
As an example of tool that uses this information, there is Damien
Lespiau x86db.
Part of the mission to add missing amd64 SSE4 instructions to Go asm.
Change-Id: I512ff26040f47a0976b3e37000fb1f37eac5b762
Reviewed-on: https://go-review.googlesource.com/55830
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
This makes it much easier to run individual failing subtests.
Use $(go env CC) instead of always defaulting to clang; this makes it
easier to test with other compilers.
Run C binaries to detect incompatible compiler/kernel pairings instead
of sniffing versions.
updates #21196
Change-Id: I0debb3cc4a4244df44b825157ffdc97b5c09338d
Reviewed-on: https://go-review.googlesource.com/52910
Run-TryBot: Bryan Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Prioritized the chunks of code with 8 or more levels of indentation.
Basically early breaks/returns and joining nested ifs.
Change-Id: I6817df1303226acf2eb904a29f2db720e4f7427a
Reviewed-on: https://go-review.googlesource.com/55630
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Current code detect runtime/cgo iff the package or sub packages imports
runtime/cgo directly. However, when we are using linkshared, imported
shared libraries might have already included runtime/cgo.
This CL handles later case by looking an actual runtime/cgo symbol.
Change-Id: I35e7dfdb5e1a939eafc95a0259ee1af9782bc864
Reviewed-on: https://go-review.googlesource.com/56310
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Test is not run in short mode, except on builders.
Change-Id: I4456830770188951e05ac13669e834a25bf569ae
Reviewed-on: https://go-review.googlesource.com/55973
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Joe Tsai <joetsai@google.com>
Reviewed-by: Joe Tsai <joetsai@google.com>
Reviewed-by: Marvin Stenger <marvin.stenger94@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Currently, we have a workaround for solaris that enforce aboslute
addressing for external symbols. However, We don't want to use the
workaround for darwin.
This CL also refactors code a little bit, because the original function
name is not appropriate now.
Updates #17490
Change-Id: Id21f9cdf33dca6a40647226be49010c2c324ee24
Reviewed-on: https://go-review.googlesource.com/54871
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Fixes#10010.
Change-Id: Ib13ac28eafed72c456d8b5b6549015cdf5fdda94
Reviewed-on: https://go-review.googlesource.com/56190
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
When calling a Go function that returns multiple values from C, cgo
generates a structure to hold the values. According to the documentation
this structure is called `struct <function-name>_return`. When compiling
for gccgo the generated structure name is `struct <function-name>_result`.
This change updates the output for gccgo to match the documentation and
output for gc.
Fixes#20910
Change-Id: Iaea8030a695a7aaf9d9f317447fc05615d8e4adc
Reviewed-on: https://go-review.googlesource.com/49350
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
TestSizes has been added in CL 50170. This test is
failing on Plan 9 because executables don't have
a DWARF symbol table.
Fixes#21480.
Change-Id: I51079abdc18ad944617bdbcfe2dad970a0cea0f2
Reviewed-on: https://go-review.googlesource.com/56210
Run-TryBot: David du Colombier <0intro@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
There are a few cases where this can be useful. Apart from the obvious
(and silly)
100*n + 200*n
where we generate one IMUL instead of two, consider:
15*n + 31*n
Currently, the compiler strength-reduces both imuls, generating:
0x0000 00000 MOVQ "".n+8(SP), AX
0x0005 00005 MOVQ AX, CX
0x0008 00008 SHLQ $4, AX
0x000c 00012 SUBQ CX, AX
0x000f 00015 MOVQ CX, DX
0x0012 00018 SHLQ $5, CX
0x0016 00022 SUBQ DX, CX
0x0019 00025 ADDQ CX, AX
0x001c 00028 MOVQ AX, "".~r1+16(SP)
0x0021 00033 RET
But combining the imuls is both faster and shorter:
0x0000 00000 MOVQ "".n+8(SP), AX
0x0005 00005 IMULQ $46, AX
0x0009 00009 MOVQ AX, "".~r1+16(SP)
0x000e 00014 RET
even without strength-reduction.
Moreover, consider:
5*n + 7*(n+1) + 11*(n+2)
We already have a rule that rewrites 7(n+1) into 7n+7, so the
generated code (without imuls merging) looks like this:
0x0000 00000 MOVQ "".n+8(SP), AX
0x0005 00005 LEAQ (AX)(AX*4), CX
0x0009 00009 MOVQ AX, DX
0x000c 00012 NEGQ AX
0x000f 00015 LEAQ (AX)(DX*8), AX
0x0013 00019 ADDQ CX, AX
0x0016 00022 LEAQ (DX)(CX*2), CX
0x001a 00026 LEAQ 29(AX)(CX*1), AX
0x001f 00031 MOVQ AX, "".~r1+16(SP)
But with imuls merging, the 5n, 7n and 11n factors get merged, and the
generated code looks like this:
0x0000 00000 MOVQ "".n+8(SP), AX
0x0005 00005 IMULQ $23, AX
0x0009 00009 ADDQ $29, AX
0x000d 00013 MOVQ AX, "".~r1+16(SP)
0x0012 00018 RET
Which is both faster and shorter; that's also the exact same code that
clang and the intel c compiler generate for the above expression.
Change-Id: Ib4d5503f05d2f2efe31a1be14e2fe6cac33730a9
Reviewed-on: https://go-review.googlesource.com/55143
Reviewed-by: Keith Randall <khr@golang.org>
The DWARF entries for type-specific sudog entries used the
channel value type instead of a pointer-to-value type for the elem field.
Fixes#21094
R=go1.10
Change-Id: I3f63a5664f42b571f729931309f2c9f6f38ab031
Reviewed-on: https://go-review.googlesource.com/50170
Reviewed-by: Ian Lance Taylor <iant@golang.org>
$ gotip tool -h says:
For more about each tool command, see 'go tool command -h'.
But it's better to suggest
go doc cmd/<command>
Fixes#18313
Change-Id: I0a36d585906a5e1879e5b7927d1b6173e97cb500
Reviewed-on: https://go-review.googlesource.com/55990
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This reduces the code footprint of code like:
println("foo=", foo, "bar=", bar)
which is fairly common in the runtime.
Prior to this change, this makes function calls to print each of:
"foo=", " ", foo, " ", "bar=", " ", bar, "\n"
After this change, this prints:
"foo= ", foo, " bar= ", bar, "\n"
This shrinks the hello world binary by 0.4%.
More importantly, this improves the instruction
density of important runtime routines.
Change-Id: I8971bdf5382fbaaf4a82bad4442f9da07c28d395
Reviewed-on: https://go-review.googlesource.com/55098
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Rather than emitting spaces and newlines for println
as we walk the expression, construct it all up front.
This enables further optimizations.
This requires using printstring instead of print in
the implementation of printsp and printnl,
on pain of infinite recursion.
That's ok; it's more efficient anyway, and just as simple.
While we're here, do it for other print routines as well.
Change-Id: I61d7df143810e00710c4d4d948d904007a7fd190
Reviewed-on: https://go-review.googlesource.com/55097
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
I noticed that we don't set an itab's function pointers at compile
time. Instead, we currently do it at executable startup.
Set the function pointers at compile time instead. This shortens
startup time. It has no effect on normal binary size. Object files
will have more relocations, but that isn't a big deal.
For PIE there are additional pointers that will need to be adjusted at
load time. There are already other pointers in an itab that need to be
adjusted, so the cache line will already be paged in. There might be
some binary size overhead to mark these pointers. The "go test -c
-buildmode=pie net/http" binary is 0.18% bigger.
Update #20505
Change-Id: I267c82489915b509ff66e512fc7319b2dd79b8f7
Reviewed-on: https://go-review.googlesource.com/44341
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
The stxr/stxrw/stxrb/stxrh instructions belong to STLXR-like instructions
set and they require special handling. The current code has no special
handling for those instructions.
The fix adds the special handling for those instructions.
Uncomment stxr/stxrw/stxrb/stxrh test cases.
Fixes#21397
Change-Id: I31cee29dd6b30b1c25badd5c7574dda7a01bf016
Reviewed-on: https://go-review.googlesource.com/54951
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Improve static branch prediction in arm64 wrapper prologue
by making the unusual case branch forwards. (Most other
architectures implement this optimization.)
Additionally, replace a CMP+BNE pair with a CBNZ
to save one instruction.
Change-Id: Id970038b34b4aaec18c101d62e2ee00f3e32a761
Reviewed-on: https://go-review.googlesource.com/54070
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Add support for generating TBZ/TBNZ instructions.
The bit-test-and-branch pattern shows up in a number of
important places, including the runtime (gc bitmaps).
Before this change, there were 3 TB[N]?Z instructions in the Go tool,
all of which were in hand-written assembly. After this change, there
are 285. Also, the go1 benchmark binary gets about 4.5kB smaller.
Fixes#21361
Change-Id: I170c138b852754b9b8df149966ca5e62e6dfa771
Reviewed-on: https://go-review.googlesource.com/54470
Run-TryBot: Philip Hofer <phofer@umich.edu>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
TestSizes has been added in CL 55551. This test is
failing on Plan 9 because executables don't have
a DWARF symbol table.
Fixes#21453.
Change-Id: I560611b49aea5417e8c5ac0cec6c7882bd9f8335
Reviewed-on: https://go-review.googlesource.com/55692
Run-TryBot: David du Colombier <0intro@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
We don't use it any more, remove it.
Change-Id: I76ce1a4c2e7048fdd13a37d3718b5abf39ed9d26
Reviewed-on: https://go-review.googlesource.com/44474
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Just use fun[0]==0 to indicate a bad itab.
Change-Id: I28ecb2d2d857090c1ecc40b1d1866ac24a844848
Reviewed-on: https://go-review.googlesource.com/44473
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Keep itabs in a growable hash table.
Use a simple open-addressable hash table, quadratic probing, power
of two sized.
Synchronization gets a bit more tricky. The common read path now
has two atomic reads, one to get the table pointer and one to read
the entry out of the table.
I set the max load factor to 75%, kind of arbitrarily. There's a
space-speed tradeoff here, and I'm not sure where we should land.
Because we use open addressing the itab.link field is no longer needed.
I'll remove it in a separate CL.
Fixes#20505
Change-Id: Ifb3d9a337512d6cf968c1fceb1eeaf89559afebf
Reviewed-on: https://go-review.googlesource.com/44472
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
ld.SymKind and objabi.RelocType have string representations,
which is human friendly. Prefer to use it.
Change-Id: I458ee0ca5866be0db8462c36cd053561a8206c95
Reviewed-on: https://go-review.googlesource.com/55253
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This fixes the -x output so that when it reports environment variables they
are correctly quoted for later execution by the shell.
Also fix -x output to use the right path to the pack tool, and note when
we are touching a file.
Fixes#21427
Change-Id: I323ef4edf9905b08bc26944b94183d8da2fa9675
Reviewed-on: https://go-review.googlesource.com/55350
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Only set MH_NOUNDEFS if there are no undefined symbols.
Doesn't seem to matter, but may as well do it right.
Change-Id: I6c472e000578346c28cf0e10f24f870e3a0de628
Reviewed-on: https://go-review.googlesource.com/55310
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
They are currently not given a size, which makes the DWARF reader
very confused. Particularly things like [4]func() get a size of -4, not 32.
Fixes#21097
Change-Id: I01e754134d82fbbe6567e3c7847a4843792a3776
Reviewed-on: https://go-review.googlesource.com/55551
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Currently go fmt formats all files sequentially.
That's a shame. Parallelize it over files.
Reduces time of go fmt ./... in std lib
from ~6.1s to ~0.9s.
Reduces time of go fmt github.com/google/syzkaller/...
from ~5.2s to ~1.8s.
Change-Id: I3d27fc25326106b2a4781e13506a25c12d5bcdc5
Reviewed-on: https://go-review.googlesource.com/45491
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Also, unexport Machoadddynlib
n=`go test -c crypto/x509 && otool -l x509.test | grep libSystem | wc -l`
Before this CL, n = 3.
After this CL, n = 1.
on my environment.
Change-Id: Ic7b8157435cc85086404860dc6c84eb0aecc5d19
Reviewed-on: https://go-review.googlesource.com/44771
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Avelino <t@avelino.xxx>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Change some configurations to enable the feature. Also add the test.
This CL doesn't include internal linking support which is tentatively
disabled due to #18968. We could do that another day.
Fixes#21220
Change-Id: I601d2d78446d36332acc70be0d5b9461ac635208
Reviewed-on: https://go-review.googlesource.com/54790
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Just like https://golang.org/cl/34783
Given cgo.go:
1 package main
2
3 /*
4 long double x = 0;
5 */
6 import "C"
7
8 func main() {
9 _ = C.x
10 _ = C.x
11 }
Before:
./cgo.go:10:6: unexpected: 16-byte float type - long double
After:
./cgo.go:9:6: unexpected: 16-byte float type - long double
The above test case is not portable. So it is tested on only amd64.
Change-Id: If0b84cf73d381a22e2ada71c8e9a6e6ec77ffd2e
Reviewed-on: https://go-review.googlesource.com/54950
Reviewed-by: Ian Lance Taylor <iant@golang.org>
We might want to replace some linker's feature by debug/macho in future.
This CL gathers information of required constants.
Change-Id: Iea14abdb32709a4f5404a17874f9c925d29ba999
Reviewed-on: https://go-review.googlesource.com/55252
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
No semantic change, just clarifying a bit by choosing better words
in a couple of places.
Change-Id: I4496062ee7909baf83d4d22d25e13ef93b358b4b
Reviewed-on: https://go-review.googlesource.com/55255
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This reverts commit f612cd704a.
Reason for revert: We thought the original change had broken the
linux/amd64 and linux/386 builders, but it turned out to be a problem
with the build infrastructure, not the change.
Change-Id: Ic3318a63464fcba8d845ac04494115a7ba620364
Reviewed-on: https://go-review.googlesource.com/55050
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
$ go tool -h says:
For more about each tool command, see 'go tool command -h'.
but it was suggested to change the suggestion to say:
see 'go doc command'
In #18313.
That would work for every tool except dist, which has no doc.go.
This change adds a doc.go file to cmd/dist.
Updates #18313
Change-Id: If67a21934b87647a69359d9c14d8de3775c587b7
Reviewed-on: https://go-review.googlesource.com/54351
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Currently all trace slices get shifted to start at time 0. This makes
it very difficult to find specific points in time unless they fall in
the first slice.
For example, right now when you click "View trace
(6.005646218s-8.155419698s)" on the trace tool's main page, the trace
view puts the first event in that slice at time 0. If you're looking
for something that happened at time 7s, you have to look at time
0.9943537s in the trace view. And if you want to subtract times taken
from different slices, you have to figure out what those time really
correspond to.
Fix this by telling the trace viewer not to shift the times when it
imports the trace. In the above example, this makes the view of that
second trace slice start at time 6.005646218s, so you don't have to do
any gymnastics to find or calculate times in later slices.
Change-Id: I04e0afda60f5573fdd8ad96238c24013297ef263
Reviewed-on: https://go-review.googlesource.com/54633
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
This updates the HTML served for the trace viewer to follow the latest
revision of the example from the upstream tracing project.
The main thing this adds is CSS for the trace viewer (which was
actually in the example at the originally referenced revision, so I'm
not sure why it got dropped). In particular, this expands the trace
viewer to use the entire browser client area, which fixes several
problems with the current page:
1. The details pane gets cut off at a strange place and can get a
scroll bar even if there's plenty of room below it on the page. This
fixes the bottom of the details pane to the bottom of the window.
2. If the track view is very tall (lots of procs), there's no way to
view the top tracks and the details pane at the same time. This fixes
this problem by limiting the height of the track view to something
less than the height of the window so it gets a scroll bar of its own
if necessary.
3. Dragging the divider between the track pane and the details pane
actually moves the bottom of the details pane without moving the
divider. Fixing the height of the trace viewer fixes this problem.
Change-Id: Ia811e72a7413417ca21c45e932c9db2724974633
Reviewed-on: https://go-review.googlesource.com/54632
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
This implements trunc, floor, and ceil in the math package
as intrinsics on ppc64x. Significant improvement mainly due
to avoiding call overhead of args and return value.
BenchmarkCeil-16 5.95 0.69 -88.40%
BenchmarkFloor-16 5.95 0.69 -88.40%
BenchmarkTrunc-16 5.82 0.69 -88.14%
Updates #21390
Change-Id: I951e182694f6e0c431da79c577272b81fb0ebad0
Reviewed-on: https://go-review.googlesource.com/54654
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Carlos Eduardo Seo <cseo@linux.vnet.ibm.com>
Reviewed-by: David Chase <drchase@google.com>
Change-Id: I8d295ea32bf56adc42171947133f3e16a88664c6
Reviewed-on: https://go-review.googlesource.com/54911
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Change-Id: I84b0e1d86728a76bc6a87fee4accf6fc43d87006
Reviewed-on: https://go-review.googlesource.com/54814
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This reverts commit f0b3626904.
Reason for revert: this change caused the runtime tests on all linux/amd64 and linux/386 builders to timeout
Change-Id: Idf8cfdfc84540e21e8da403e74df5596a1d9327b
Reviewed-on: https://go-review.googlesource.com/54490
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Mostly node and position parameters that are no longer used.
Also remove an unnecessary node variable while at it.
Found with github.com/mvdan/unparam.
Change-Id: I88f9bd5d20bfc5b0f6f63ea81869daa246175061
Reviewed-on: https://go-review.googlesource.com/54130
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
If we've already imported a named type, then there's no need to
process its associated methods except to validate that the signature
matches the existing known method.
However, the current import code still creates a new function node for
each method, saves its inline body (if any), and adds the node to the
global importlist. Because of this, the duplicate methods are never
garbage collected.
This CL changes the compiler to avoid amassing uncollectable garbage
or performing any unnecessary processing.
This is particularly noticeable for protobuf-heavy code. For the
motivating Go package, this CL reduced compile max-RSS from ~12GB to
~3GB and compile time from ~65s to ~50s.
Passes toolstash -cmp for std, cmd, and k8s.io/kubernetes/cmd/....
Change-Id: Ib53ba9f2ad3212995671cf6ba220ee8a56d8d009
Reviewed-on: https://go-review.googlesource.com/51331
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
This change enables buildmode c-shared on ppc64le.
A bug was fixed in runtime/rt0_linux_ppc64le.s that was necessary to
make this work. In _rt0_ppc64le_linux_lib, there is code to store
the value of r2 onto the caller's stack. However, if this file
is compiled using a build mode that maintains the TOC address in
r2, then instructions will be inserted at the beginning of this
function to generate the r2 value for the callee, not the caller.
That means the r2 value for the callee is stored onto the caller's
stack. If caller and callee don't have the same r2 values, then
the caller will restore the wrong r2 value after it returns. This
situation can happen when using dlopen since the caller of this
function will be in ld64.so and will definitely have a different
TOC.
Updates #20756
Change-Id: I6e165e0d0716e73721bbbcc520e8302e4856e3ba
Reviewed-on: https://go-review.googlesource.com/53890
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Otherwise, vet might have false positives when "C" is a variable and
we're just using a method on it. Or when an import was renamed to "C".
Add test files for both of these cases.
Fixes#20655.
Change-Id: I55fb93119444a67fcf7891ad92653678cbd4670e
Reviewed-on: https://go-review.googlesource.com/45551
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Rob Pike <r@golang.org>
These rules trigger a few times during make.bash.
When we eliminate boundedness checks from walk.go
we'll rely on them more heavily.
Updates #19692
Change-Id: I268c36ae2f1401c68dd685b15f2d30f5d6971176
Reviewed-on: https://go-review.googlesource.com/43775
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
gc.Sysfunc must not be called concurrently.
We set up runtime routines used by the backend
prior to doing any backend compilation.
I missed the 387 ones; fix that.
Sysfunc should have been unexported during 1.9.
I will rectify that in a subsequent CL.
Fixes#21352
Change-Id: I8386eaa1e05879c25c672b9c9fc693c938e9aeb6
Reviewed-on: https://go-review.googlesource.com/54090
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Avelino <t@avelino.xxx>
TryBot-Result: Gobot Gobot <gobot@golang.org>
ADDSDmem comment said f32 (likely a copy-paste mistake).
Also swap ADDSSmem and ADDSDmem positions in the list to uniform the
list order.
Fixes#21225
Change-Id: I26bb116900c1cf4c4e6faeef613d7318c9c85b98
Reviewed-on: https://go-review.googlesource.com/52071
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
Reviewed-by: Keith Randall <khr@golang.org>
The vet tool only reports a type checking error when invoked with -v.
Don't let that by itself cause vet to exit with an error exit status.
Updates #21188
Change-Id: I172c13d46c35d49e229e96e833683d8c82a77de7
Reviewed-on: https://go-review.googlesource.com/52851
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Rob Pike <r@golang.org>
Fixes#21205
Change-Id: I81b001eb42cbf2a5d5b7b82eb63548b22f501be5
Reviewed-on: https://go-review.googlesource.com/52110
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
For address of an auto or arg, on all non-x86 architectures
the assembler backend encodes the actual SP offset in the
instruction but leaves the offset in Prog unchanged. When the
assembly is printed in compile -S, it shows an offset
relative to pseudo FP/SP with an actual hardware SP base
register (e.g. R13 on ARM). This is confusing. Unset the
base register if it is indeed SP, so the assembly output is
consistent. If the base register isn't SP, it should be an
error and the error output contains the actual base register.
For address loading instructions, the base register isn't set
in the compiler on non-x86 architectures. Set it. Normally it
is SP and will be unset in the change mentioned above for
printing. If it is not, it will be an error and the error
output contains the actual base register.
No change in generated binary, only printed assembly. Passes
"go build -a -toolexec 'toolstash -cmp' std cmd" on all
architectures.
Fixes#21064.
Change-Id: Ifafe8d5f9b437efbe824b63b3cbc2f5f6cdc1fd5
Reviewed-on: https://go-review.googlesource.com/49432
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Debuggers use DWARF information to find local variables on the
stack and in registers. Prior to this CL, the DWARF information for
functions claimed that all variables were on the stack at all times.
That's incorrect when optimizations are enabled, and results in
debuggers showing data that is out of date or complete gibberish.
After this CL, the compiler is capable of representing variable
locations more accurately, and attempts to do so. Due to limitations of
the SSA backend, it's not possible to be completely correct.
There are a number of problems in the current design. One of the easier
to understand is that variable names currently must be attached to an
SSA value, but not all assignments in the source code actually result
in machine code. For example:
type myint int
var a int
b := myint(int)
and
b := (*uint64)(unsafe.Pointer(a))
don't generate machine code because the underlying representation is the
same, so the correct value of b will not be set when the user would
expect.
Generating the more precise debug information is behind a flag,
dwarflocationlists. Because of the issues described above, setting the
flag may not make the debugging experience much better, and may actually
make it worse in cases where the variable actually is on the stack and
the more complicated analysis doesn't realize it.
A number of changes are included:
- Add a new pseudo-instruction, RegKill, which indicates that the value
in the register has been clobbered.
- Adjust regalloc to emit RegKills in the right places. Significantly,
this means that phis are mixed with StoreReg and RegKills after
regalloc.
- Track variable decomposition in ssa.LocalSlots.
- After the SSA backend is done, analyze the result and build location
lists for each LocalSlot.
- After assembly is done, update the location lists with the assembled
PC offsets, recompose variables, and build DWARF location lists. Emit the
list as a new linker symbol, one per function.
- In the linker, aggregate the location lists into a .debug_loc section.
TODO:
- currently disabled for non-X86/AMD64 because there are no data tables.
go build -toolexec 'toolstash -cmp' -a std succeeds.
With -dwarflocationlists false:
before: f02812195637909ff675782c0b46836a8ff01976
after: 06f61e8112a42ac34fb80e0c818b3cdb84a5e7ec
benchstat -geomean /tmp/220352263 /tmp/621364410
completed 15 of 15, estimated time remaining 0s (eta 3:52PM)
name old time/op new time/op delta
Template 199ms ± 3% 198ms ± 2% ~ (p=0.400 n=15+14)
Unicode 96.6ms ± 5% 96.4ms ± 5% ~ (p=0.838 n=15+15)
GoTypes 653ms ± 2% 647ms ± 2% ~ (p=0.102 n=15+14)
Flate 133ms ± 6% 129ms ± 3% -2.62% (p=0.041 n=15+15)
GoParser 164ms ± 5% 159ms ± 3% -3.05% (p=0.000 n=15+15)
Reflect 428ms ± 4% 422ms ± 3% ~ (p=0.156 n=15+13)
Tar 123ms ±10% 124ms ± 8% ~ (p=0.461 n=15+15)
XML 228ms ± 3% 224ms ± 3% -1.57% (p=0.045 n=15+15)
[Geo mean] 206ms 377ms +82.86%
name old user-time/op new user-time/op delta
Template 292ms ±10% 301ms ±12% ~ (p=0.189 n=15+15)
Unicode 166ms ±37% 158ms ±14% ~ (p=0.418 n=15+14)
GoTypes 962ms ± 6% 963ms ± 7% ~ (p=0.976 n=15+15)
Flate 207ms ±19% 200ms ±14% ~ (p=0.345 n=14+15)
GoParser 246ms ±22% 240ms ±15% ~ (p=0.587 n=15+15)
Reflect 611ms ±13% 587ms ±14% ~ (p=0.085 n=15+13)
Tar 211ms ±12% 217ms ±14% ~ (p=0.355 n=14+15)
XML 335ms ±15% 320ms ±18% ~ (p=0.169 n=15+15)
[Geo mean] 317ms 583ms +83.72%
name old alloc/op new alloc/op delta
Template 40.2MB ± 0% 40.2MB ± 0% -0.15% (p=0.000 n=14+15)
Unicode 29.2MB ± 0% 29.3MB ± 0% ~ (p=0.624 n=15+15)
GoTypes 114MB ± 0% 114MB ± 0% -0.15% (p=0.000 n=15+14)
Flate 25.7MB ± 0% 25.6MB ± 0% -0.18% (p=0.000 n=13+15)
GoParser 32.2MB ± 0% 32.2MB ± 0% -0.14% (p=0.003 n=15+15)
Reflect 77.8MB ± 0% 77.9MB ± 0% ~ (p=0.061 n=15+15)
Tar 27.1MB ± 0% 27.0MB ± 0% -0.11% (p=0.029 n=15+15)
XML 42.7MB ± 0% 42.5MB ± 0% -0.29% (p=0.000 n=15+15)
[Geo mean] 42.1MB 75.0MB +78.05%
name old allocs/op new allocs/op delta
Template 402k ± 1% 398k ± 0% -0.91% (p=0.000 n=15+15)
Unicode 344k ± 1% 344k ± 0% ~ (p=0.715 n=15+14)
GoTypes 1.18M ± 0% 1.17M ± 0% -0.91% (p=0.000 n=15+14)
Flate 243k ± 0% 240k ± 1% -1.05% (p=0.000 n=13+15)
GoParser 327k ± 1% 324k ± 1% -0.96% (p=0.000 n=15+15)
Reflect 984k ± 1% 982k ± 0% ~ (p=0.050 n=15+15)
Tar 261k ± 1% 259k ± 1% -0.77% (p=0.000 n=15+15)
XML 411k ± 0% 404k ± 1% -1.55% (p=0.000 n=15+15)
[Geo mean] 439k 755k +72.01%
name old text-bytes new text-bytes delta
HelloSize 694kB ± 0% 694kB ± 0% -0.00% (p=0.000 n=15+15)
name old data-bytes new data-bytes delta
HelloSize 5.55kB ± 0% 5.55kB ± 0% ~ (all equal)
name old bss-bytes new bss-bytes delta
HelloSize 133kB ± 0% 133kB ± 0% ~ (all equal)
name old exe-bytes new exe-bytes delta
HelloSize 1.04MB ± 0% 1.04MB ± 0% ~ (all equal)
Change-Id: I991fc553ef175db46bb23b2128317bbd48de70d8
Reviewed-on: https://go-review.googlesource.com/41770
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
The linker is pretty good at combining a bunch of symbols into a
section, so let it do .debug_ranges the normal way. Along the way,
remove a bunch of globals that were only used by one function that would
only be called once per invocation.
Change-Id: I1a528a438b193c41e7c444e8830516b07f11affc
Reviewed-on: https://go-review.googlesource.com/43890
Reviewed-by: Alessandro Arzilli <alessandro.arzilli@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
When the compiler decomposes a user variable, track its origin so that
it can be recomposed during DWARF generation.
Change-Id: Ia71c7f8e7f4d65f0652f1c97b0dda5d9cad41936
Reviewed-on: https://go-review.googlesource.com/50878
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Fix an oversight in decompose that caused floats to be missing from the
Names list.
Change-Id: I5db9c9498e9a4421742389eb929752fdac873b38
Reviewed-on: https://go-review.googlesource.com/50877
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
When we start tracking the mapping from Value to Prog, valueProgs will
be confusing. Disambiguate.
Change-Id: Ib3b302fedb7eb0ff1bde789d70a11656d82f0897
Reviewed-on: https://go-review.googlesource.com/50876
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
After we track decomposition, offset could mean stack offset or offset
in recomposed variable. Disambiguate.
Change-Id: I4d810b8c0dcac7a4ec25ac1e52898f55477025df
Reviewed-on: https://go-review.googlesource.com/50875
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
It is possible to have an unexported name with a nil package,
for an embedded field whose type is a pointer to an unexported type.
We must encode that fact in the type..namedata symbol name,
to avoid incorrectly merging an unexported name with an exported name.
Fixes#21120
Change-Id: I2e3879d77fa15c05ad92e0bf8e55f74082db5111
Reviewed-on: https://go-review.googlesource.com/50710
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
This avoids an error from clang when using -nopie during compilation,
and permits us to check that the entire build succeeds.
Updates #21042
Change-Id: I2e6c7d5c97a85c223ed3288622bbb58ce33b8774
Reviewed-on: https://go-review.googlesource.com/50874
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Fixes TestGoBuildUmask when the user has a POSIX ACL on the Go source tree.
Fixes#17909.
Change-Id: I5bc19099af8353afd41071258f4f317612b4c8c1
Reviewed-on: https://go-review.googlesource.com/50370
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Load/store-merging and move optimizations can result in unaligned
memory accesses. This is fine so long as the load/store instruction
used does not take a relative offset. In the SSA rules this means we
must not merge (MOVDaddr (SB)) ops into loads/stores unless we can
guarantee the alignment of the target.
Fixes#21048.
Change-Id: I70f13a62a148d5f0a56e704e8f76e36b4a4226d9
Reviewed-on: https://go-review.googlesource.com/49250
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Currently, Windows stacks are either 128kB or 2MB depending on whether
the binary uses cgo. This is because we assume that Go system stacks
and the small amount of C code invoked by the standard library can
operate within smaller stacks, but general Windows C code assumes
larger stacks.
However, it's easy to call into arbitrary C code using the syscall
package on Windows without ever importing cgo into a binary. Such
binaries need larger system stacks even though they don't use cgo.
Fix this on 64-bit by increasing the system stack size to 2MB always.
This only costs address space, which is free enough on 64-bit to not
worry about. We keep (for now) the existing heuristic on 32-bit, where
address space comes at more of a premium.
Updates #20975.
Change-Id: Iaaaa9a2fcbadc825cddc797aaaea8d34ef8debf2
Reviewed-on: https://go-review.googlesource.com/49331
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Framepointer is the default now. Only print an X: list
if the settings are _not_ the default.
Before:
$ go tool compile -V
compile version devel +a5f30d9508 Sun Jul 16 14:43:48 2017 -0400 X:framepointer
$ go1.8 tool compile -V
compile version go1.8 X:framepointer
$
After:
$ go tool compile -V
compile version devel +a5f30d9508 Sun Jul 16 14:43:48 2017 -0400
$ go1.9 tool compile -V # imagined
compile version go1.9
$
Perpetuates #18317.
Change-Id: I981ba5c62be32e650a166fc9740703122595639b
Reviewed-on: https://go-review.googlesource.com/49252
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Fails on iOS because CC_FOR_TARGET points to clangwrap.sh in the
original GOROOT. We could fix that but it doesn't seem worth it.
Fails on Android with "exec format error". I'm not sure why but I
doubt it is interesting.
Fails on Plan 9 because the original GOROOT is being preserved in some
unknown way. This is issue #21016.
Updates #21016
Change-Id: I4e7115d734fc7bf21e5a2ba18fb6ad0bfa31c735
Reviewed-on: https://go-review.googlesource.com/48650
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: David du Colombier <0intro@gmail.com>
Reviewed-by: Elias Naur <elias.naur@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This is necessary to make a relocated GOROOT work correctly.
Fixes#20997
Change-Id: I18624bd2e109721066cd9e4a887a12583ab79f5d
Reviewed-on: https://go-review.googlesource.com/48550
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Previous code failed to account for particular control flow
involving nested loops when updating phi function inputs.
Fix involves:
1) remove incorrect shortcut
2) generate a "better" order for children in dominator tree
3) note inner-loop updates and check before applying
outer-loop updates.
Fixes#20675.
Change-Id: I2fe21470604b5c259e777ad8b15de95f7706894d
Reviewed-on: https://go-review.googlesource.com/45791
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
CL 44352 changed the behavior of SIGINT, which can break tests that
themselves use SIGINT. I think we can only implement this if the
testing package has a way to know whether the code under test is using
SIGINT, but os/signal does not provide an API for that. Roll back for
1.9 and think about this again for 1.10.
Updates #19397
Change-Id: I021c314db2b9d0a80d0088b120a6ade685459990
Reviewed-on: https://go-review.googlesource.com/48370
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
When a local variable is moved to the heap the declaration position
should be preserved so that later on we can assign it to the correct
DW_TAG_lexical_block.
Fixes#20959
Change-Id: I3700ef53c68ccd506d0633f11374ad88a52b2898
Reviewed-on: https://go-review.googlesource.com/47852
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
ld.addpltsym adds an R_X86_64_JMP_SLOT dynamic relocation to .rela.plt
and uses Addaddrplus to reference the GOT in Elf64_Rela.r_offset.
Addaddrplus results in an R_ADDR relocation, which here we transform
into an R_X86_64_64 dynamic relocation. This is wrong for several
reasons:
1. .rela.plt is not a writable, relro section. It is mapped read-only,
causing the dynamic linker to segfault when it tried to handle the
relocation. This was the immediate cause of internal PIE cgo
crashes.
2. Relocations targetting other reloc sections are, as far as I can
tell, undefined behavior in the ELF spec and are unlikely to be a
good idea.
3. Even if the relocation did work, it isn't what we want. The
relocation, if successfully handled, would have put an absolute
address as the JMP_SLOT offset, but it should be the offset from the
beginning of the binary, just like any other relocation. What we want
is a statically resolved R_ADDR relocation, just as is used below for
the R_X86_64_64 relocation.
Skipping the .rela.plt allows reloc() to handle these R_ADDR
relocations.
With this CL, internal PIE cgo binaries work.
Updates #18968
Change-Id: Ie74e6fe249e88150baa0e340b1cb128cf7f28673
Reviewed-on: https://go-review.googlesource.com/47837
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This reverts commit 168eb9cf33.
CL 47831 fixes the issue with plugins on ARMv5, so we can re-enable the test.
Updates #19674.
Change-Id: Idcb29f93ffb0460413f1fab5bb82fa2605795038
Reviewed-on: https://go-review.googlesource.com/47834
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The text before CL 45816 was:
-timeout t
If a test runs longer than t, panic.
The default is 10 minutes (10m).
CL 45816 was supposed to be about clarifying test vs test binary,
and it did add the clarification of referring to "duration d",
but it also introduced incorrect text about timeout 0.
The new text in this CL preserves the good change and
eliminates the incorrect one:
-timeout d
If a test binary runs longer than duration d, panic.
The default is 10 minutes (10m).
For #14780.
Change-Id: I4f79d6e48ed9295bc9f34a36aa90d3b03b40d7f5
Reviewed-on: https://go-review.googlesource.com/47571
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Wrong instructions "MOVW 8(F0), R1" and "MOVW R0<<0(F1), R1"
are silently accepted, and all Fx are treated as Rx.
The patch checks all those illegal base registers.
fixes#20724
Change-Id: I05d41bb43fe774b023205163b7daf4a846e9dc88
Reviewed-on: https://go-review.googlesource.com/46132
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
