Commit Graph

47904 Commits

Author SHA1 Message Date
Cherry Zhang
5b328c4a2f cmd/compile: use desired register only if it satisfies register mask
In the register allocator, if possible, we allocate a value to its
desired register (the ideal register for its next use). In some
cases the desired register does not satisfies the value's output
register mask. We should not use the register in this case.

In the following example, v33 is going to be returned as a
function result, so it is allocated to its desired register AX.
However, its Op cannot use AX as output, causing miscompilation.

v33 = CMOVQEQF <int> v24 v28 v29 : AX (~R0[int])
v35 = MakeResult <int,int,mem> v33 v26 v18
Ret v35

Change-Id: Id0f4f27c4b233ee297e83077e3c8494fe193e664
Reviewed-on: https://go-review.googlesource.com/c/go/+/314630
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2021-04-28 16:13:40 +00:00
Paschalis Tsilias
cbb3f09047 testing: add -shuffle=off|on|N to alter the execution order of tests and benchmarks
This CL adds a new flag to the testing package and the go test command
which randomizes the execution order for tests and benchmarks.
This can be useful for identifying unwanted dependencies
between test or benchmark functions.
The flag is off by default. If `-shuffle` is set to `on` then the system
clock will be used as the seed value. If `-shuffle` is set to an integer
N, then N will be used as the seed value. In both cases, the seed will
be reported for failed runs so that they can reproduced later on.

Fixes #28592

Change-Id: I62e7dfae5f63f97a0cbd7830ea844d9f7beac335
Reviewed-on: https://go-review.googlesource.com/c/go/+/310033
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emmanuel@orijtech.com>
Trust: Bryan C. Mills <bcmills@google.com>
2021-04-28 16:06:21 +00:00
Ian Lance Taylor
e51246c881 runtime: consolidate Windows time constants into single copy
Change-Id: I1a583d3da9cca4ac51f3fec9b508b7638b452d60
Reviewed-on: https://go-review.googlesource.com/c/go/+/314270
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
2021-04-28 15:58:43 +00:00
Ian Lance Taylor
92c9f3a9b8 cmd/go: include C/C++/Fortran compiler version in build ID
This will force a rebuild if the C/C++/Fortran compiler changes.

No test because a real test requires installing two different compilers.

Fixes #40042

Change-Id: I83cc88ade90d665a6fce06435068f39c811e43af
Reviewed-on: https://go-review.googlesource.com/c/go/+/314276
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2021-04-28 15:57:49 +00:00
Cherry Zhang
becb9a278f test: do not run fuse test in noopt mode
Change-Id: Iad8ac2253ce28fd0a331bde36836d1b7f25797bd
Reviewed-on: https://go-review.googlesource.com/c/go/+/314632
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
2021-04-28 15:55:10 +00:00
Ian Lance Taylor
24ea547a21 cmd/link: don't pass -Wl,--dynamic-linker if -static
As with -rdynamic, clang will pass -Wl,--dynamic-linker to the linker
even when linking statically. When using lld this will produce a statically
linked executable with a dynamic interpreter, which will crash at runtime.
This CL changes the linker to drop -Wl,--dynamic-linker when using -static,
as it already does with -rdynamic.

This has become more important since CL 310349, which changes the linker
to always pass a -Wl,--dynamic-linker option if the Go linker is invoked
with a -I option.

Change-Id: I68ed431064f02c70018bc0547585e5b0ebd20a41
Reviewed-on: https://go-review.googlesource.com/c/go/+/314412
Trust: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2021-04-28 15:52:58 +00:00
Manlio Perillo
12af403624 cmd/go/internal/bug: use envcmd instead of go env
Add the printGoEnv function to print the go environment variables, using
the envcmd package instead of invoking go env.

Add the PrintEnv function to the envcmd package, to avoid duplicating
code.

Updates #45803

Change-Id: I38d5b936c0ebb16e741ffbee4309b95d6d0ecc6c
Reviewed-on: https://go-review.googlesource.com/c/go/+/314230
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Michael Matloob <matloob@golang.org>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
2021-04-28 15:47:34 +00:00
unbyte
5c69cb2a5b cmd/go: populate module info even if an error occurs in loading package
The existing implementation ignores module info if there is any error loading the package.

Fixes #44287

Change-Id: I24142e4c7256517292fc654e29d759871b80bc09
GitHub-Last-Rev: 28e9bf85e8
GitHub-Pull-Request: golang/go#45777
Reviewed-on: https://go-review.googlesource.com/c/go/+/313549
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Michael Matloob <matloob@golang.org>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Michael Matloob <matloob@golang.org>
2021-04-28 15:10:38 +00:00
Cherry Zhang
11052d77a3 cmd/link: use R12 as trampoline scratch register on ARM
The external linker uses R12. Do the same. We previously use R11,
the temp register in Go ABI. This does not really matter if the
caller is Go code, because all registers are clobbered at call.
But it the caller is C code, it may assume R11 live across a call.
Using R11 may clobber live value. On the callee side, R12 is not
an argument register in both Go and C calling convention.

Change-Id: I958c5dad52aa51bb282a7ad420f5423863e69c14
Reviewed-on: https://go-review.googlesource.com/c/go/+/314454
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2021-04-28 15:08:29 +00:00
Cherry Zhang
4a7effa418 cmd/compile: mark R12 clobbered for special calls
In external linking mode the external linker may insert
trampolines, which use R12 as a scratch register. So a call could
potentially clobber R12 if the target is laid out too far. Mark
R12 clobbered.

Also, we will use R12 for trampolines in the Go linker as well.

CL 310731 updated the generated rewrite files so imports are
grouped, but the generator was not updated to do so. Grouped
imports are nice. But as those are generated files, for
simplicity and my laziness, just regenerate with the current
generator (which makes imports not grouped).

Change-Id: Iddb741ff7314a291ade5fbffc7d315f555808409
Reviewed-on: https://go-review.googlesource.com/c/go/+/314453
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2021-04-28 14:01:59 +00:00
Daniel Martí
4fe324dd0f cmd/go: make TOOLEXEC_IMPORTPATH consistent with 'go list -f {{.ImportPath}}'
TOOLEXEC_IMPORTPATH is useful for the toolexec program to know what
package is currently being built. This is otherwise tricky to figure out.

Unfortunately, for test packages it was lacking. In the added test case,
we have a total of four packages in 'go list -test':

	test/main
	test/main.test
	test/main [test/main.test]
	test/main_test [test/main.test]

And, when running with -toolexec, one would get the following values:

        # test/main_test [test/main.test]
        compile TOOLEXEC_IMPORTPATH="test/main_test"
        # test/main [test/main.test]
        compile TOOLEXEC_IMPORTPATH="test/main"
        # test/main.test
        compile TOOLEXEC_IMPORTPATH="test/main.test"

Note how the " [test/main.test]" suffixes are missing. Because of that,
when one sees TOOLEXEC_IMPORTPATH="test/main", it is ambiguous whether
the regular "test/main" package is meant, or its test variant, otherwise
known as "test/main [test/main.test]" and including foo_test.go

To fix this, we need unambiguous strings to identify the packages
involved, just like one can do with "go list -test". "go list" already
has such a field, ImportPath, which is also used when printing output
from each build "action" as seen above.

That string is not really an import path - internally, it's
load.Package.Desc, and called a "description". However, it makes sense
to be consistent with "go list -json", because it's the source of truth
for practically all tools interacting with the Go toolchain.

To keep cmd/go more consistent, "go list -f {{.ImportPath}}" now calls
Package.Desc as well, instead of having its own copy of the string
concatenation for ForTest.

Fixes #44963.

Change-Id: Ibce7fbb5549209dac50526043c0c7daa0beebc08
Reviewed-on: https://go-review.googlesource.com/c/go/+/313770
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Daniel Martí <mvdan@mvdan.cc>
2021-04-28 13:49:52 +00:00
Joel Sing
f68878f0fc cmd/dist,runtime: support cgo on openbsd/mips64
Add support for cgo on openbsd/mips64.

Fixes #43005

Change-Id: I2386204f53fa984a01a9d89f0b6c96455768f326
Reviewed-on: https://go-review.googlesource.com/c/go/+/275896
Trust: Joel Sing <joel@sing.id.au>
Run-TryBot: Joel Sing <joel@sing.id.au>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2021-04-28 12:51:42 +00:00
eric fang
92d1afe989 cmd/compile/ssa: optimize the derivable known branch of If block
When the control value of a If block is known for a particular inbound edge
because its value can be inferred from the control value of its predecessor,
then this inbound edge can be redirected to the known successor directly,
This CL optimizes this kind of cases to eliminate unnecessary comparision.

For example, the following piece of code comes from runtime.atoi,
if !neg && un > uint(maxInt) {
	return 0, false
}
if neg && un > uint(maxInt)+1 {
	return 0, false
}

Before this optimization, if the first "if" statement does not return, both
conditions of the second "if" statement will be checked. But obviously the
value of neg is known through the first "if" statement, and there is no need
to check neg repeatedly.

After this optimization, this redundancy check is eliminated, and the execution
logic becomes as follows.
if !neg {
	if un > uint(maxInt) {
		return 0, false
	}
} else {
	if un > uint(maxInt)+1 {
		return 0, false
	}
}

This CL does not bring significant performance changes, but it makes the code
structure look more reasonable.

Statistical data from tool compilecmp on Linux/amd64:
name                      old time/op       new time/op       delta
Template                        380ms ± 4%        385ms ± 3%  +1.16%  (p=0.000 n=50+49)
Unicode                         168ms ± 9%        169ms ± 9%    ~     (p=0.421 n=49+46)
GoTypes                         1.99s ± 4%        2.02s ± 4%  +1.48%  (p=0.000 n=49+49)
Compiler                        188ms ± 8%        188ms ± 9%    ~     (p=0.997 n=49+50)
SSA                             11.8s ± 2%        12.0s ± 2%  +1.24%  (p=0.000 n=48+50)
Flate                           242ms ± 6%        244ms ± 9%    ~     (p=0.307 n=46+49)
GoParser                        361ms ± 3%        366ms ± 4%  +1.23%  (p=0.000 n=48+49)
Reflect                         836ms ± 3%        842ms ± 3%  +0.70%  (p=0.004 n=48+48)
Tar                             335ms ± 3%        340ms ± 4%  +1.47%  (p=0.000 n=49+46)
XML                             432ms ± 4%        437ms ± 4%  +1.11%  (p=0.002 n=49+49)
LinkCompiler                    701ms ± 4%        704ms ± 5%    ~     (p=0.278 n=49+50)
ExternalLinkCompiler            1.83s ± 3%        1.84s ± 3%  +0.51%  (p=0.034 n=48+49)
LinkWithoutDebugCompiler        436ms ± 6%        438ms ± 6%    ~     (p=0.419 n=48+49)
[Geo mean]                      612ms             617ms       +0.84%

name                      old alloc/op      new alloc/op      delta
Template                       38.7MB ± 1%       39.1MB ± 1%  +1.19%  (p=0.000 n=50+50)
Unicode                        28.1MB ± 0%       28.1MB ± 0%  +0.20%  (p=0.000 n=49+45)
GoTypes                         168MB ± 1%        170MB ± 1%  +1.05%  (p=0.000 n=48+49)
Compiler                       23.0MB ± 1%       23.1MB ± 1%  +0.63%  (p=0.000 n=50+50)
SSA                            1.54GB ± 1%       1.55GB ± 1%  +0.85%  (p=0.000 n=50+50)
Flate                          23.6MB ± 1%       23.9MB ± 1%  +1.36%  (p=0.000 n=43+46)
GoParser                       35.0MB ± 1%       35.3MB ± 1%  +0.94%  (p=0.000 n=50+50)
Reflect                        84.7MB ± 1%       86.1MB ± 1%  +1.72%  (p=0.000 n=49+49)
Tar                            34.5MB ± 1%       34.9MB ± 1%  +1.07%  (p=0.000 n=47+48)
XML                            44.2MB ± 3%       44.6MB ± 3%  +0.70%  (p=0.003 n=50+49)
LinkCompiler                    128MB ± 0%        128MB ± 0%  +0.01%  (p=0.004 n=49+50)
ExternalLinkCompiler            120MB ± 0%        120MB ± 0%  +0.01%  (p=0.000 n=49+50)
LinkWithoutDebugCompiler       77.3MB ± 0%       77.3MB ± 0%  +0.02%  (p=0.000 n=50+50)
[Geo mean]                     69.1MB            69.6MB       +0.75%

file      before    after     Δ       %
addr2line 4049276   4051308   +2032   +0.050%
api       5248940   5248996   +56     +0.001%
asm       4868093   4868037   -56     -0.001%
buildid   2627666   2626026   -1640   -0.062%
cgo       4614432   4615040   +608    +0.013%
compile   23298888  23301267  +2379   +0.010%
cover     4591609   4591161   -448    -0.010%
dist      3449638   3450254   +616    +0.018%
doc       3925667   3926363   +696    +0.018%
fix       3322936   3323464   +528    +0.016%
link      6628632   6629560   +928    +0.014%
nm        3991753   3996497   +4744   +0.119%
objdump   4396119   4395615   -504    -0.011%
pack      2399719   2399535   -184    -0.008%
pprof     13616418  13622866  +6448   +0.047%
test2json 2646121   2646081   -40     -0.002%
trace     10233087  10226359  -6728   -0.066%
vet       7117994   7121066   +3072   +0.043%
total     111026988 111039495 +12507  +0.011%

On linux arm64:
name                      old time/op       new time/op       delta
Template                        284ms ± 1%        286ms ± 1%  +0.70%  (p=0.000 n=49+50)
Unicode                         125ms ± 3%        125ms ± 2%    ~     (p=0.548 n=50+50)
GoTypes                         1.69s ± 1%        1.71s ± 1%  +1.02%  (p=0.000 n=49+49)
Compiler                        125ms ± 1%        124ms ± 2%  -0.35%  (p=0.020 n=50+50)
SSA                             12.7s ± 1%        12.8s ± 1%  +1.21%  (p=0.000 n=49+49)
Flate                           172ms ± 1%        173ms ± 1%  +0.20%  (p=0.047 n=50+50)
GoParser                        265ms ± 1%        266ms ± 1%  +0.64%  (p=0.000 n=50+50)
Reflect                         651ms ± 1%        650ms ± 1%    ~     (p=0.079 n=48+48)
Tar                             246ms ± 1%        246ms ± 1%    ~     (p=0.202 n=50+46)
XML                             328ms ± 1%        332ms ± 1%  +1.28%  (p=0.000 n=50+49)
LinkCompiler                    600ms ± 1%        599ms ± 1%    ~     (p=0.264 n=50+50)
ExternalLinkCompiler            1.88s ± 1%        1.90s ± 0%  +1.36%  (p=0.000 n=50+50)
LinkWithoutDebugCompiler        365ms ± 1%        365ms ± 1%    ~     (p=0.602 n=50+46)
[Geo mean]                      490ms             492ms       +0.47%

name                      old alloc/op      new alloc/op      delta
Template                       38.8MB ± 1%       39.1MB ± 1%  +0.92%  (p=0.000 n=44+42)
Unicode                        28.4MB ± 0%       28.4MB ± 0%  +0.22%  (p=0.000 n=44+45)
GoTypes                         169MB ± 1%        171MB ± 1%  +1.12%  (p=0.000 n=50+50)
Compiler                       23.2MB ± 1%       23.3MB ± 1%  +0.56%  (p=0.000 n=42+43)
SSA                            1.55GB ± 0%       1.56GB ± 0%  +0.91%  (p=0.000 n=48+49)
Flate                          23.7MB ± 2%       24.0MB ± 1%  +1.20%  (p=0.000 n=50+50)
GoParser                       35.3MB ± 1%       35.6MB ± 1%  +0.88%  (p=0.000 n=50+50)
Reflect                        85.0MB ± 0%       86.5MB ± 0%  +1.70%  (p=0.000 n=49+48)
Tar                            34.5MB ± 1%       34.9MB ± 1%  +1.03%  (p=0.000 n=47+50)
XML                            43.8MB ± 2%       44.0MB ± 0%  +0.41%  (p=0.002 n=49+38)
LinkCompiler                    136MB ± 0%        136MB ± 0%  +0.01%  (p=0.006 n=50+49)
ExternalLinkCompiler            127MB ± 0%        127MB ± 0%  +0.02%  (p=0.000 n=49+50)
LinkWithoutDebugCompiler       84.1MB ± 0%       84.1MB ± 0%    ~     (p=0.534 n=50+50)
[Geo mean]                     70.4MB            70.9MB       +0.69%

file      before    after     Δ       %
addr2line 4006004   4004556   -1448   -0.036%
api       5029716   5028828   -888    -0.018%
asm       4936863   4934943   -1920   -0.039%
buildid   2594947   2594099   -848    -0.033%
cgo       4399702   4399502   -200    -0.005%
compile   22233139  22230486  -2653   -0.012%
cover     4443681   4443881   +200    +0.005%
dist      3365902   3365486   -416    -0.012%
doc       3776175   3776151   -24     -0.001%
fix       3218624   3218600   -24     -0.001%
link      6365001   6361409   -3592   -0.056%
nm        3923345   3923065   -280    -0.007%
objdump   4295473   4296673   +1200   +0.028%
pack      2390561   2389393   -1168   -0.049%
pprof     12866419  12865115  -1304   -0.010%
test2json 2587113   2585561   -1552   -0.060%
trace     9609814   9610846   +1032   +0.011%
vet       6790272   6789760   -512    -0.008%
total     106832751 106818354 -14397  -0.013%

Update: #37608

Change-Id: I2831238b12e3af5aef2261f64f804bf0a8b43f86
Reviewed-on: https://go-review.googlesource.com/c/go/+/244737
Reviewed-by: eric fang <eric.fang@arm.com>
Reviewed-by: Keith Randall <khr@golang.org>
Trust: eric fang <eric.fang@arm.com>
Run-TryBot: eric fang <eric.fang@arm.com>
TryBot-Result: Go Bot <gobot@golang.org>
2021-04-28 02:39:09 +00:00
eric fang
9726c78539 cmd/asm: add check for register and shift/extension combination on arm64
The current code lacks a check on whether the register and shift/extension
combination is valid, for example the follow instructions also compiles.
	ADD     F1<<1, R1, R3
	ADD     V1<<1, R1, R3
	MOVW    (R9)(F8.SXTW<<2), R19
	VST1    R4.D[1], (R0)

Actually only general registers can perform shift operations, and element
and arrangement extensions are only applicable to vector registers. This
CL adds a check for the register and shift/extension combination on arm64.

Change-Id: I93dd9343e92a66899cba8eaf4e0ac5430e94692b
Reviewed-on: https://go-review.googlesource.com/c/go/+/312571
Trust: eric fang <eric.fang@arm.com>
Reviewed-by: eric fang <eric.fang@arm.com>
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: eric fang <eric.fang@arm.com>
TryBot-Result: Go Bot <gobot@golang.org>
2021-04-28 01:19:40 +00:00
eric fang
f439a76253 cmd/internal/obj/arm64: fix the wrong error message of out-of-range checking
The error message of checking whether the offset value of load/store
instruction is out of range is wrong. The right range is [-256, 255], not
[-255, 254]. The CL fixes it.

Change-Id: Ia342957f1f6bcec65eceb45944221d3972641bed
Reviewed-on: https://go-review.googlesource.com/c/go/+/313891
Reviewed-by: eric fang <eric.fang@arm.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Trust: eric fang <eric.fang@arm.com>
Run-TryBot: eric fang <eric.fang@arm.com>
2021-04-28 01:16:38 +00:00
Cuong Manh Le
c9f43507c6 cmd/compile: fix typechecking logical operators panic with non-boolean operand
In CL 255899, we added code to make clearer error when non-bool used
as operand to logical operators. The code is safe, because node type
is guaranteed to be non-nil.

In CL 279442, we refactored typechecking arith, including moving
typechecking logical operators to separate case. Now we have to
explicitly check if operand type is not nil, because calling Expr can
set operand type nil for non-bool operands.

Fixes #45804

Change-Id: Ie2b6e18f65c0614a803b343f60e78ee1d660bbeb
Reviewed-on: https://go-review.googlesource.com/c/go/+/314209
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2021-04-28 00:49:58 +00:00
Paul E. Murphy
983dea90c1 cmd/link: disable plugin support if cgo is disabled
Functional plugin support requires cgo to be enabled. Disable
it if the environment has disabled cgo.

This prevents unexpected linker failures when linking large
binaries with cgo disabled which use the plugin package.

Fixes #45564

Change-Id: Ib71f0e089f7373b7b3e3cd53da3612291e7bc473
Reviewed-on: https://go-review.googlesource.com/c/go/+/314449
Run-TryBot: Paul Murphy <murp@ibm.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Lynn Boger <laboger@linux.vnet.ibm.com>
2021-04-27 22:46:28 +00:00
Rob Findley
214c8dd80c go/types: factor out index/slice expr handling
This is a port of CL 308370 to go/types. There are some differences in
the index checking code, but the methodology for moving the code was the
same: replace `goto Error` with `x.mode = invalid; return`.

Change-Id: I880f577a7720e6ad8a5b096207001fcf7620396d
Reviewed-on: https://go-review.googlesource.com/c/go/+/312095
Trust: Robert Findley <rfindley@google.com>
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2021-04-27 21:55:07 +00:00
Julien Tant
645cb62ee3 testing: document that TestMain can be used with benchmarks
Fixes #45764

Change-Id: Ie6c18bb5c20721c2ffa8b4a9cf9f97cdc665a450
GitHub-Last-Rev: 8bcea7e0ff
GitHub-Pull-Request: golang/go#45808
Reviewed-on: https://go-review.googlesource.com/c/go/+/314349
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Trust: Bryan C. Mills <bcmills@google.com>
2021-04-27 21:44:16 +00:00
SataQiu
30002e6656 cmd/go/internal/modload: treat \ as a path separator instead of a shell special character
According to the code comment, \ should be treated as a path separator.
See fileNameOK in golang.org/x/mod/module/module.go.

Change-Id: I05e05246005191ecccfecf46848aba5cb1359956
Reviewed-on: https://go-review.googlesource.com/c/go/+/310429
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Trust: Robert Findley <rfindley@google.com>
2021-04-27 21:16:55 +00:00
cuiweixie
b9dfaf77f5 cmd/compile/internal/walk: merge operations
Change-Id: I018872da519dfb4aa6c252ea28fc09289c2d9711
GitHub-Last-Rev: 5969776197
GitHub-Pull-Request: golang/go#45795
Reviewed-on: https://go-review.googlesource.com/c/go/+/313550
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
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2021-04-27 19:40:24 +00:00
Ian Lance Taylor
13e87cda00 time: increase slop for TestTicker
Also sleep a bit each time it fails, in case the system is overloaded.

Fixes #37332

Change-Id: Iabf3d0a27b5834c1e2a87c826b6206146b4f62c5
Reviewed-on: https://go-review.googlesource.com/c/go/+/313849
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2021-04-27 19:37:31 +00:00
Keith Randall
f432d3fc41 cmd/compile: fix nongeneric closures in generic functions
Ensure that formal parameter Names are correctly copied and marked
with the correct Curfn. We need to ensure this even when the underlying
closure has no type parameters.

(Aside: it is strange that the types of things contain formal
parameter names that need to be copied. Maybe that's an underlying
larger problem that needs to be fixed.)

Fixes #45738

Change-Id: Ia13d69eea992ff7080bd44065115bc52eb624e73
Reviewed-on: https://go-review.googlesource.com/c/go/+/313652
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2021-04-27 19:30:11 +00:00
Bryan C. Mills
8ab7064e33 cmd/go: use a real Go version in the go.mod files in TestScript/mod_readonly
For some reason, the go.mod file added to this test in CL 147281 lists
'go 1.20' instead of the version that was actually current when the
go.mod file was added.

That causes the test's behavior to change under lazy loading, because
1.20 is above the threshold to trigger lazy-loading invariants (1.17).

For #36460

Change-Id: I92400996cb051ab30e99bfffafd91ff32a1e7087
Reviewed-on: https://go-review.googlesource.com/c/go/+/314049
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2021-04-27 19:18:02 +00:00
Ian Lance Taylor
0c3557e6ad syscall: move TestForegroundSignal create call out of goroutine
That way the skip takes effect.

Also ignore the result of calling TIOCSPGRP when cleaing up TestForeground.
It has started to fail for some reason, and the result doesn't matter.

Also call TIOCSPGRP to clean up in TestForegroundSignal.

For #37217

Change-Id: I2e4282d7d91ad9a198eeb12cef01c2214c2a98c2
Reviewed-on: https://go-review.googlesource.com/c/go/+/314271
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2021-04-27 19:12:41 +00:00
kumakichi
291eb0178f go: various minor cleanups with the help of Goland
• fix some typos
    • remove superfluous conversions/parentheses
    • remove superfluous nil checks

Change-Id: I428bf6a7be551b79270567047878c3076dd6f2ff
GitHub-Last-Rev: 3b1c7573cf
GitHub-Pull-Request: golang/go#45799
Reviewed-on: https://go-review.googlesource.com/c/go/+/314069
Reviewed-by: Robert Griesemer <gri@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>
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2021-04-27 18:57:27 +00:00
Felix Geisendörfer
0ae9c3b98b runtime/pprof: fix block profile bias
Block profiles were biased towards infrequent long events over frequent
short events. This fix corrects the bias by aggregating shorter events
as longer but less frequent in the profiles. As a result their
cumulative duration will be accurately represented in the profile
without skewing their sample mean (duration/count).

Credit to @dvyukov for suggesting to adjust the count in the
saveblockevent function.

Fixes #44192.

Change-Id: I71a99d7f6ebdb2d484d44890a2517863cceb4004
Reviewed-on: https://go-review.googlesource.com/c/go/+/299991
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2021-04-27 18:54:49 +00:00
Bryan C. Mills
8e0023b81b cmd/go/internal/load: treat packages with errors as potentially main packages
If a package declares 'package main' but for some reason we fail to
read its name (for example, due to a permission or checksum error),
we may be tempted to drop the package from the output of
mainPackagesOnly. However, that leads to a confusing
"no packages loaded from …" error message.

Instead, we will treat packages with errors as potentially-main
packages, and print the error. At least if we print why the package is
broken, the user will understand that the weird behavior is due to the
broken package rather than, say, a typo on their part in the command
arguments.

Updates #42088
For #36460

Change-Id: I033c0d28ac7d105d9df3ba5f9327e5c0c2a29954
Reviewed-on: https://go-review.googlesource.com/c/go/+/314050
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2021-04-27 18:34:55 +00:00
Ray Wu
bd2175e1b1 cmd/go: show warnings about symlinks only for patterns containing ...
Go commands show a warning message any time a pattern is expanded and a
symlink to a directory is encountered. For monorepo with non Go projects
using symlinks underneath, the output of go commands could be spammed by
this warning.

This commit includes the behavior change to only print this warning when
there's a pattern containing ... .

Fixes #35941

Change-Id: I094da2628bcd47b86fee8c6529d1066aa013a43b
Reviewed-on: https://go-review.googlesource.com/c/go/+/311890
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2021-04-27 18:17:01 +00:00
Cherry Zhang
222101549a syscall: restore nosplit for ptrace1 on Darwin
ptrace1 must be nosplit because it is called from
forAndExecInChild. It was marked nosplit in the generated code
but not in the generator. CL 313230 regenerated the code and lost
the nosplit mark. This CL restores it.

Change-Id: I4645d83650f1818bed3cb650328bba97074b6b2d
Reviewed-on: https://go-review.googlesource.com/c/go/+/314249
Trust: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
2021-04-27 17:18:15 +00:00
Rob Findley
cde6a675bc go/scanner: optimize scanIdentifier
While profiling parsing, I noticed that scanIdentifier was extremely
hot, and could be optimized: it is responsible for a significant
fraction of scanning and had a lot of unnecessary branching, bounds
checks, and function calls.

This CL implements some of those optimizations, while trying to strike a
balance between optimization and readability. It achieves this by
optimizing for the common case of ASCII identifiers, falling back on the
slower scan when encountering the first non-ASCII character.

Benchmark results:

name                               old time/op    new time/op    delta
Scan-12                              16.9µs ± 4%    15.8µs ± 5%   -6.92%  (p=0.000 n=20+18)
ScanFiles/go/types/expr.go-12         793µs ± 4%     672µs ± 6%  -15.23%  (p=0.000 n=20+20)
ScanFiles/go/parser/parser.go-12     1.08ms ± 6%    0.90ms ± 4%  -16.68%  (p=0.000 n=20+20)
ScanFiles/net/http/server.go-12      1.44ms ± 4%    1.23ms ± 5%  -14.58%  (p=0.000 n=18+20)
ScanFiles/go/scanner/errors.go-12    40.7µs ± 2%    32.6µs ± 3%  -20.01%  (p=0.000 n=19+20)

Change-Id: If78380004248e3ea75cfc78eb7f38f528124dced
Reviewed-on: https://go-review.googlesource.com/c/go/+/308611
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2021-04-27 17:05:58 +00:00
Rémy Oudompheng
074a49bfe8 strconv: remove unused extfloat (Grisu3) ftoa code
Change-Id: Ie8995362f9e8072b173d08820330d2d1e512aa71
Reviewed-on: https://go-review.googlesource.com/c/go/+/314029
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2021-04-27 17:03:53 +00:00
Dan Scales
55c517a8b3 cmd/compile: fix handling of ir.CurFunc during stenciling
The transform functions (specifically transformArgs, which is used from
transformCall/transformReturn) require that ir.CurFunc is set correctly.
Since transformCall() is used on the call of an instantiated generic
function, we need to set ir.CurFunc correctly in stencil(). Also,
correctly save/restore ir.CurFunc in genericSubst().

Without this fix, ir.CurFunc can be nil when we call TransformCall()
from stencil(), which leads to some temp variables being added
incorrectly to ir.TodoFunc (which leads to the fatal panic in the
issue).

Fixes #45722

Change-Id: Iddf4a67d28f2100dde8cde5dbc9ca1e00dad6089
Reviewed-on: https://go-review.googlesource.com/c/go/+/313869
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2021-04-27 16:55:20 +00:00
yangwenmai
d553c0144d bits: use same expression with system bit size
Change-Id: Ibce07f8f36f7c64f7022ce656f8efbec5dff3f82
Reviewed-on: https://go-review.googlesource.com/c/go/+/313829
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Reviewed-by: Keith Randall <khr@golang.org>
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2021-04-27 16:25:40 +00:00
Rob Findley
bc6288794d go/scanner: improve variety in benchmarks for file scanning
BenchmarkScanFile was scanning scanner.go, which makes comparison
difficult for a CL modifying that file. That file is also is not
necessarily representative syntax.

Add a few additional files as subtests to provide a larger variety of
metrics.

Change-Id: Ib78303c2546debd84a0b5478ae438ba891d9e6e9
Reviewed-on: https://go-review.googlesource.com/c/go/+/308610
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2021-04-27 15:57:56 +00:00
Rob Findley
6fa12172d9 go/parser: add benchmarks for syntax-only parsing and object resolution
Change-Id: I73d1b2d18ab4051443d66c60df493d1163d0ba3f
Reviewed-on: https://go-review.googlesource.com/c/go/+/306150
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2021-04-27 15:57:10 +00:00
Tobias Klauser
88a8a27056 os: don't check non-nil err twice in Symlink on windows
Change-Id: I398d324723025b559fdca783fc334de9be68f2d1
Reviewed-on: https://go-review.googlesource.com/c/go/+/314030
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2021-04-27 15:50:45 +00:00
Michael Anthony Knyszek
0b9ca4d907 runtime/metrics: add tiny allocs metric
Currently tiny allocations are not represented in either MemStats or
runtime/metrics, but they're represented in MemStats (indirectly) via
Mallocs. Add them to runtime/metrics by first merging
memstats.tinyallocs into consistentHeapStats (just for simplicity; it's
monotonic so metrics would still be self-consistent if we just read it
atomically) and then adding /gc/heap/tiny/allocs:objects to the list of
supported metrics.

Change-Id: Ie478006ab942a3e877b4a79065ffa43569722f3d
Reviewed-on: https://go-review.googlesource.com/c/go/+/312909
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2021-04-27 13:59:22 +00:00
Ian Lance Taylor
7d22c2181b syscall: restore signal mask after setting foreground process group
Fixes #37217

Change-Id: I0151bb77fc4c4552d1b19c31d784943b72f84b80
Reviewed-on: https://go-review.googlesource.com/c/go/+/313653
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2021-04-27 13:50:09 +00:00
Rob Findley
39844971fb go/types: don't panic when checking a ListExpr in exprInternal
As an alternative to CL 312149, add a catch-all error message in
exprInternal when encountering a ListExpr, rather than panicking.

We still might want something like CL 312149 to improve the error
message or recovery from bad indexing.

Change-Id: I865f7cc4eefa4a3b7bd8f3100df96d0144e1712f
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2021-04-27 13:46:16 +00:00
Paul E. Murphy
6edd573218 cmd/link: enforce larger alignment on split ppc64 text sections
When laying out, we lazily increase the alignment for text sections
as symbols are found requiring more. This works if the start of
the virtual address (VA) for the section is greater than or equal
to the alignment required by any symbols placed in this section.

The minimum alignment of the section is only known after all
symbols are placed. The starting VA of this section is adjusted
upwards in ld.(*Link).address to meet the requested alignment.

This is a problem if the starting VA of the text section is not
already aligned. This can happen when the final symbol placed
into the previous section results in an insufficiently aligned
start VA of the next text section.

To workaround this, additional text sections are split, and both
the starting VA, and alignment of the section are aligned up to
match the known worst case alignment.

64B is chosen as the worst case alignment for all ppc64 targets,
as it will respect PCALIGN and eventually prefixed instructions
which will be introduced in the future.

Likewise, the xcoff size calculations need to be improved to
handle padding bytes when function symbols have been aligned.
This is done by tracking the largest valid VA offset encountered
when placing symbols.

Change-Id: Iefef09a1ee7c963fb8dfce2288a084a95cb77fca
Reviewed-on: https://go-review.googlesource.com/c/go/+/307431
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2021-04-27 11:55:52 +00:00
Paul E. Murphy
1eca6aa747 cmd/internal/obj: refactor ppc64 address relocation code generation
The code for generating a long constant versus generating an address
(either via a relocation, or known offset) should be handled in the
same place.

Resolve this by classifying memory arguments as C_LACON (a long
address constant) instead of C_LCON (a long constant).

Likewise, reorder AMOVD/AMOVW optab entries to keep similar
classifications near each other. An extra optab entry for
DWORD is also added to continue handling C_LACON arguments
correctly.

Change-Id: I5ce28400492a071f615125a9b8d260826f1600d7
Reviewed-on: https://go-review.googlesource.com/c/go/+/312296
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2021-04-27 11:50:41 +00:00
Alex Brainman
e0815d041c runtime: replace --buildmode with -buildmode in tests
While debugging issue #45638, I discovered that some tests were using
--buildmode command line parameter instead of -buildmode.

The --buildmode parameter is handled properly by the flag package - it
is read as -buildmode. But we should correct code anyway.

Updates #45638

Change-Id: I75cf95c7d11dcdf4aeccf568b2dea77bd8942352
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2021-04-27 08:39:25 +00:00
Alex Brainman
ca8e8317be runtime: add missing import "C" in TestLibraryCtrlHandler
CL 211139 added TestLibraryCtrlHandler. But the CL left out import "C"
line in the test file that is supposed to be build with Cgo.

While debugging issue #45638, I discovered that the DLL built during
TestLibraryCtrlHandler does not have Dummy function. Adding import "C"
makes Dummy function appear in DLL function list.

TestLibraryCtrlHandler does not actually calls Dummy function. So I
don't see how this change affects issue #45638, but still let's make
this code correct.

Updates #45638

Change-Id: Ibab8fed29ef2ae446d0815842cf0bd040a5fb943
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2021-04-27 08:36:54 +00:00
Matthew Dempsky
cb34026a95 cmd/compile: tighten exportWriter.qualifiedIdent signature
It always takes an *ir.Name and would panic given anything else
anyway, so tighten the signature to match.

Change-Id: I44fec5c5cc6d7f0b9c59eb91c9f9633137485360
Reviewed-on: https://go-review.googlesource.com/c/go/+/314009
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2021-04-27 05:44:56 +00:00
lixianyang
c249491572 doc: change <a/> to </a> in spec
Change-Id: I21d0ee83c9204d51c587bd944209df2232b460ad
GitHub-Last-Rev: 47fab8dc58
GitHub-Pull-Request: golang/go#45771
Reviewed-on: https://go-review.googlesource.com/c/go/+/313449
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2021-04-27 04:44:55 +00:00
Bryan C. Mills
7ef0237d89 cmd/go/internal/modload: clean up error reporting
• Consolidate 'if ld.AllowErrors' conditions into an 'ld.errorf'
  method.

• Rename SilenceErrors to SilencePackageErrors and clarify its
  documentation. (There is currently no way to silence errors in the
  module graph. Perhaps we should add one, but for now let's at least
  clarify the existing behavior.)

• Move 'tidy -v' verbose logging into LoadPackages, where other
  logging happens.

• Make checkMultiplePaths a loader method (since it only matters
  during package loading anyway).

• Check package and module-graph errors in loadFromRoots instead of
  LoadPackages. These checks were previously omitted on the
  ImportFromFiles path, which seems likely to be a bug. (We now
  suppress package errors explicitly in ImportFromFiles, which at
  least makes the bug more explicit.)

This somewhat simplifies the code structure in preparation for
the lazy-mode tidy implementation.

For #36460

Change-Id: I3ce3586c6934989d5194f00f99e7cc4423cf767f
Reviewed-on: https://go-review.googlesource.com/c/go/+/313229
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2021-04-27 03:24:21 +00:00
Bryan C. Mills
3cc3a16029 cmd/go: add tests for convergence in 'go mod tidy'
For #36460

Change-Id: I40194bb1ebab77459e5c9d43bdac4d9c1b826ac2
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2021-04-27 03:23:38 +00:00
Cuong Manh Le
434e12f772 cmd/compile: add more doc for Name.Defn
As discussion in CL 313289, Name.Defn is also be set for variables
declared in type switch, or name function.

Change-Id: I3deb3d79fca269356e4432b77df7c7720a523674
Reviewed-on: https://go-review.googlesource.com/c/go/+/313889
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2021-04-27 02:39:52 +00:00
Rob Findley
15105dd4b5 go/types: walk all imports when determining package name ambiguity
CL 209578 disambiguated paths among imported packages, but as
demonstrated in #43119, formatted types may reference packages that are
not directly imported.

Fix this by recursively walking all imports to determine whether there
is any ambiguity in the import graph. This might result in
over-qualification of names, but it is straightforward and should
eliminate any ambiguity.

In general this should be fine, but might introduce risk of infinite
recursion in the case of an importer bug, or performance problems for
very large import graphs. Mitigate the former by tracking seen packages,
and the latter by only walking the import graph once an error has been
produced.

Fixes #43119

Change-Id: If874f050ad0e808db8e354c2ffc88bc6d64fd277
Reviewed-on: https://go-review.googlesource.com/c/go/+/313035
Trust: Robert Findley <rfindley@google.com>
Trust: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2021-04-27 02:20:29 +00:00