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Commit Graph

34206 Commits

Author SHA1 Message Date
Wei Xiao
531e6c06c4 cmd/asm: refine Go assembly for ARM64
Some ARM64-specific instructions (such as SIMD instructions) are not supported.
This patch adds support for the following:
1. Extended register, e.g.:
     ADD	Rm.<ext>[<<amount], Rn, Rd
     <ext> can have the following values:
       UXTB, UXTH, UXTW, UXTX, SXTB, SXTH, SXTW and SXTX
2. Arrangement for SIMD instructions, e.g.:
     VADDP	Vm.<T>, Vn.<T>, Vd.<T>
     <T> can have the following values:
       B8, B16, H4, H8, S2, S4 and D2
3. Width specifier and element index for SIMD instructions, e.g.:
     VMOV	Vn.<T>[index], Rd // MOV(to general register)
     <T> can have the following values:
       S and D
4. Register List, e.g.:
     VLD1	(Rn), [Vt1.<T>, Vt2.<T>, Vt3.<T>]
5. Register offset variant, e.g.:
     VLD1.P	(Rn)(Rm), [Vt1.<T>, Vt2.<T>] // Rm is the post-index register
6. Go assembly for ARM64 reference manual
     new added instructions are required to have according explanation items in
     the manual and items for existed instructions will be added incrementally

For more information about the refinement background, please refer to the
discussion (https://groups.google.com/forum/#!topic/golang-dev/rWgDxCrL4GU)

This patch only adds syntax and doesn't break any assembly that already exists.

Change-Id: I34e90b7faae032820593a0e417022c354a882008
Reviewed-on: https://go-review.googlesource.com/41654
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-10-13 13:41:19 +00:00
Jed Denlea
31cd20a70e image/gif: try harder to use global color table
The GIF format allows for an image to contain a global color table which
might be used for some or every frame in an animated GIF.  This palette
contains 24-bit opaque RGB values.  An individual frame may use the
global palette and enable transparency by picking one number to be
transparent, instead of the color value in the palette.

image/gif decodes a GIF, which contains an []*image.Paletted that holds
each frame.  When decoded, if a frame has a transparent color and uses
the global palette, a copy of the global []color.Color is made, and the
transparency color index is replaced with color.RGBA{}.

When encoding a GIF, each frame's palette is encoded to the form it
might exist in a GIF, up to 768 bytes "RGBRGBRGBRGB...". If a frame's
encoded palette is equal to the encoded global color table, the frame
will be encoded with the flag set to use the global color table,
otherwise the frame's palette will be included.

So, if the color in the global color table that matches the transparent
index of one frame wasn't black (and it frequently is not), reencoding a
GIF will likely result in a larger file because each frame's palette
will have to be encoded inline.

This commit takes a frame's transparent color index into account when
comparing an individual image.Paletted's encoded color table to the
global color table.

Fixes #22137

Change-Id: I5460021da6e4d7ce19198d5f94a8ce714815bc08
Reviewed-on: https://go-review.googlesource.com/68313
Reviewed-by: Nigel Tao <nigeltao@golang.org>
2017-10-13 04:28:53 +00:00
David Chase
e45e490296 cmd/compile: attempt to deflake debug_test.go
Excluded when -short because it still runs relatively long,
but deflaked.

Removed timeouts from normal path and ensured that they were
not needed and that reference files did not change.

Use "tbreak" instead of "break" with gdb to reduce chance
of multiple hits on main.main.  (Seems not enough, but a
move in the right direction).

By default, testing ignores repeated lines that occur when
nexting.  This appears to sometimes be timing-dependent and
is the observed source of flakiness in testing so far.
Note that these can also be signs of a bug in the generated
debugging output, but it is one of the less-confusing bugs
that can occur.

By default, testing with gdb uses compilation with
inlining disabled to prevent dependence on library code
(it's a bug that library code is seen while Nexting, but
the bug is current behavior).

Also by default exclude all source files outside /testdata
to prevent accidental dependence on library code.  Note that
this is currently only applicable to dlv because (for the
debugging information we produce) gdb does not indicate a
change in the source file for inlined code.

Added flags -i and -r to make gdb testing compile with
inlining and be sensitive to repeats in the next stream.
This is for developer-testing and so we can describe these
problems in bug reports.

Updates #22206.

Change-Id: I9a30ebbc65aa0153fe77b1858cf19743bdc985e4
Reviewed-on: https://go-review.googlesource.com/69930
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-13 03:25:23 +00:00
Tim Cooper
245e386e4c reflect: allow Copy to a byte array or byte slice from a string
This somewhat mirrors the special case behavior of the copy built-in.

Fixes #22215

Change-Id: Ic353003ad3de659d3a6b4e9d97295b42510f3bf7
Reviewed-on: https://go-review.googlesource.com/70431
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-13 02:35:56 +00:00
Frank Somers
c14dcfda6b runtime: factor amd64 specifics from vdso_linux.go
This is a preparation step for adding vDSO support on linux/386.

This change relocates the elf64 and amd64 specifics from
vdso_linux.go to a new vdso_linux_amd64.go.

This should enable vdso_linux.go to be used for vDSO
support on linux architectures other than amd64.

- Relocate the elf64X structure definitions appropriate to amd64,
  and change their names to elfX so that the code in vdso_linux.go
  is ELFnn-agnostic.

- Relocate the sym_keys and corresponding __vdso_* variables
  appropriate to amd64.

- Provide an amd64-specific constant for the maximum byte size of
  an array, and use this in vdso_linux.go to compute constants for
  sizing the elf structure arrays traversed in the loaded vDSO.

Change-Id: I1edb4e4ec9f2d79b7533aa95fbd09f771fa4edef
Reviewed-on: https://go-review.googlesource.com/69391
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-13 02:04:20 +00:00
David Crawshaw
c58b98b2d6 cmd/link, runtime: put hasmain bit in moduledata
Currently we look to see if the main.main symbol address is in the
module data text range. This requires access to the main.main
symbol, which usually the runtime has, but does not when building
a plugin.

To avoid a dynamic relocation to main.main (which I haven't worked
out how to have the linker generate on darwin), stop using the
symbol. Instead record a boolean in the moduledata if the module
has the main function.

Fixes #22175

Change-Id: If313a118f17ab499d0a760bbc2519771ed654530
Reviewed-on: https://go-review.googlesource.com/69370
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-13 01:13:33 +00:00
David Crawshaw
d06815ba3f cmd/link: split PE loader into its own package
For #22095

Change-Id: I8f48fce571b69a7e8edf2ad7733ffdfd38676e63
Reviewed-on: https://go-review.googlesource.com/70310
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-12 21:35:43 +00:00
Tobias Klauser
fd9fac2c7c cmd/compile: add two error position tests for the typechecker
Follow CL 41477 and add two more line position tests for yyerror calls
in the typechecker which are currently not tested.

Update #19683

Change-Id: Iacd865195a3bfba87d8c22655382af267aba47a9
Reviewed-on: https://go-review.googlesource.com/70251
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
2017-10-12 20:50:20 +00:00
Matthew Dempsky
53bbddd527 cmd/compile: intrinsify runtime/internal/sys.Ctz{32,64} on ppc64
These functions are identical to math/bits.TrailingZeros{32,64}, which
are already intrinsified on ppc64.

Change-Id: If7ee57e7afe53154874f4b66bacdb6237806128a
Reviewed-on: https://go-review.googlesource.com/70350
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-10-12 20:01:16 +00:00
Ian Lance Taylor
56dec8dde2 test: add test case that gccgo miscompiled
Error was

main.go:7:11: error: import error at 162: expected ‘<type ’

Change-Id: Iacfe4bfa003d7708a21ebc89ad1ab2d4a3b041a8
Reviewed-on: https://go-review.googlesource.com/70290
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2017-10-12 19:02:09 +00:00
Austin Clements
97920373fa cmd/link: generate PC ranges for compilation unit DIEs
When we split separate packages into separate compilation units, we
lost PC range information because it was no longer contiguous. This
brings it back by constructing proper per-package PC range tables.

Change-Id: Id0ab5187e08ac5d13b3d3794977bfc857a56224f
Reviewed-on: https://go-review.googlesource.com/69974
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2017-10-12 18:56:26 +00:00
Austin Clements
d4dda76b5f cmd/link: one DWARF compilation unit per package
Currently, the linker generates one huge DWARF compilation unit for
the entire Go binary. This commit creates a separate compilation unit
and line table per Go package.

We temporarily lose compilation unit PC range information, since it's
now discontiguous, so harder to emit. We'll bring it back in the next
commit.

Beyond being "more traditional", this has various technical
advantages:

* It should speed up line table lookup, since that requires a
  sequential scan of the line table. With this change, a debugger can
  first locate the per-package line table and then scan only that line
  table.

* Once we emit compilation unit PC ranges again, this should also
  speed up various other debugger reverse PC lookups.

* It puts us in a good position to move more DWARF generation into the
  compiler, which could produce at least the CU header, per-function
  line table fragments, and per-function frame unwinding info that the
  linker could simply paste together.

* It will let us record a per-package compiler command-line flags
  (#22168).

Change-Id: Ibac642890984636b3ef1d4b37fe97f4453c2cc84
Reviewed-on: https://go-review.googlesource.com/69973
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-12 18:56:23 +00:00
Austin Clements
ce6e0b089f cmd/link: remove silly sym.R[:0] truncation
The DWARF code currently clears all section relocations every time it
creates a section. This is unnecessary and confusing, so don't do it.

This dates back to
https://codereview.appspot.com/7891044/diff/26001/src/cmd/ld/dwarf.c.
At the time, this was only done for one symbol and that symbol was
used solely for collecting relocations (which is why it made sense to
clear the relocations but not the actual data). Furthermore, DWARF
generation potentially required two passes, so it was important to
clear the state from the first pass. None of this is true now, but
this pattern had been cargo-culted all over the dwarf.go.

Change-Id: I87d4ff8ccd5c807796241559be46168ce3ccb49a
Reviewed-on: https://go-review.googlesource.com/70312
Run-TryBot: Austin Clements <austin@google.com>
Run-TryBot: Heschi Kreinick <heschi@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-12 18:56:20 +00:00
Austin Clements
77c27c3102 cmd/link: eliminate .debug_aranges
The .debug_aranges section is an odd vestige of DWARF, since its
contents are easy and efficient for a debugger to reconstruct from the
attributes of the top-level compilation unit DIEs. Neither GCC nor
clang emit it by default these days. GDB and Delve ignore it entirely.
LLDB will use it if present, but is happy to construct the index from
the compilation unit attributes (and, indeed, a remarkable variety of
other ways if those aren't available either).

We're about to split up the compilation units by package, which means
they'll have discontiguous PC ranges, which is going to make
.debug_aranges harder to construct (and larger).

Rather than try to maintain this essentially unused code, let's
simplify things and remove it.

Change-Id: I8e0ccc033b583b5b8908cbb2c879b2f2d5f9a50b
Reviewed-on: https://go-review.googlesource.com/69972
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
2017-10-12 18:56:18 +00:00
Heschi Kreinick
a0402b6bf8 cmd/link: suppress unnecessary DWARF relocs that confuse dsymutil
During Mach-O linking, dsymutil takes the DWARF from individual object
files and combines it into a debug archive. Because it's content-aware,
it doesn't need our help to do its job. Nonetheless, it does try to
honor relocations that are present in its input.

When dsymutil encounters a relocation, it uses the value of that
relocation as an index into the debug map to find its final location.
When it does that, it's assuming that the value is an address in the
object file. But DWARF references are section-relative. So when it
processes a relocation for a DWARF reference, it gets confused,
and if the value happens to match the address of a function or
data symbol, it will rewrite it incorrectly.

Since the relocations don't help, and can hurt, drop them when
externally linking a Mach-O binary.

Fixes #22068

Change-Id: I8ec36da626575d9f6c8d0e7a0b76eab8ba22d62c
Reviewed-on: https://go-review.googlesource.com/68330
Run-TryBot: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-12 18:51:54 +00:00
Elias Naur
764a6ac29e runtime: don't restore the alternate signal stack on ios
The alternative signal stack doesn't work on ios, so the setup of
the alternative stack was skipped. The corresponding unminitSignals
was effectively a no-op on ios until CL 70130. Skip unminitSignals
on ios to restore the previous behaviour.

For the ios builders.

Change-Id: I5692ca7f5997e6b9d10cc5f2383a5a37c42b133c
Reviewed-on: https://go-review.googlesource.com/70270
Run-TryBot: Elias Naur <elias.naur@gmail.com>
Reviewed-by: Austin Clements <austin@google.com>
2017-10-12 16:59:32 +00:00
Russ Cox
6054f87f3a cmd/go: delete p.Internal.Target in favor of p.Target
The two are not meaningfully different, and it is confusing to have two.

Change-Id: Ie6a355ea4d79fb4bb79bf5124071a866038b19ba
Reviewed-on: https://go-review.googlesource.com/70211
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-12 13:56:15 +00:00
Alex Brainman
862fb86c6e internal/poll: only call SetFileCompletionNotificationModes for sockets
CL 36799 made SetFileCompletionNotificationModes to be called for
file handles. I don't think it is correct. Revert that change.

Fixes #22024
Fixes #22207

Change-Id: I26260e8a727131cffbf60958d79eca2457495554
Reviewed-on: https://go-review.googlesource.com/69871
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-12 07:13:23 +00:00
Alex Brainman
c37647fc3a internal/poll: do not call SetFileCompletionNotificationModes if it is broken
Current code assumes that SetFileCompletionNotificationModes
is safe to call even if we know that it is not safe to use
FILE_SKIP_COMPLETION_PORT_ON_SUCCESS flag. It appears (see issue #22149),
SetFileCompletionNotificationModes crashes when we call it without
FILE_SKIP_COMPLETION_PORT_ON_SUCCESS flag.

Do not call SetFileCompletionNotificationModes in that situation.
We are allowed to do that, because SetFileCompletionNotificationModes
is just an optimisation.

Fixes #22149

Change-Id: I0ad3aff4eabd8c27739417a62c286b1819ae166a
Reviewed-on: https://go-review.googlesource.com/69870
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-12 07:12:36 +00:00
Artyom Pervukhin
9ce43ce667 image/gif: make Decode only keep the first frame in memory
Decode decodes entire GIF image and returns the first frame as an
image.Image. There's no need for it to keep every decoded frame in
memory except for the one it returns.

Fixes #22199

Change-Id: I76b4bd31608ebc76a1a3df02e85c20eb80df7877
Reviewed-on: https://go-review.googlesource.com/69890
Reviewed-by: Nigel Tao <nigeltao@golang.org>
2017-10-12 05:44:11 +00:00
Austin Clements
58c7b1d160 runtime: fix dragonfly/amd64
CL 69292 unified the amd64 entry-points, but Dragonfly doesn't follow
the same entry-point argument conventions as most other amd64
platforms. Fix the Dragonfly entry point.

Change-Id: I0f84e2e4101ce68217af185ee9baaf455b8b6dad
Reviewed-on: https://go-review.googlesource.com/70212
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-12 04:03:50 +00:00
Ian Lance Taylor
67388e9866 doc: recommend building Go 1.4 with CGO_ENABLED=0
Fixes #21054

Change-Id: I016486dc62c04a80727f8da7d1dcec52f2c7f344
Reviewed-on: https://go-review.googlesource.com/62291
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Reviewed-by: Chris Broadfoot <cbro@golang.org>
2017-10-12 01:03:14 +00:00
David du Colombier
926373ea79 runtime: fix crash on Plan 9
Since CL 46037, the runtime is crashing after calling
exitThread on Plan 9.

The exitThread function shouldn't be called on
Plan 9, because the system manages thread stacks.

Fixes #22221.

Change-Id: I5d61c9660a87dc27e4cfcb3ca3ddcb4b752f2397
Reviewed-on: https://go-review.googlesource.com/70190
Run-TryBot: David du Colombier <0intro@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2017-10-12 00:11:33 +00:00
Matthew Dempsky
a509cae90d cmd/compile: record InlCost in export data
Previously, we were treating cross-package function calls as free for
inlining budgeting.

In theory, we should be able to recompute InlCost from the
exported/reimported function bodies. However, that process mutates the
structure of the Node AST enough that it doesn't preserve InlCost. To
avoid unexpected issues, just record and restore InlCost in the export
data.

Fixes #19261.

Change-Id: Iac2bc0d32d4f948b64524aca657051f9fc96d92d
Reviewed-on: https://go-review.googlesource.com/70151
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-10-11 23:20:44 +00:00
Daniel Martí
1fbeccb15a cmd/compile: deduplicate a few lines in swt.go
Noticed while reading some code that the two branches in this loop body
shared the last statements. Rewrite it in a way that they are not
duplicated.

Passes toolstash -cmp on std.

Change-Id: I3356ca9fa37c32eee496e221d7830bfc581dade1
Reviewed-on: https://go-review.googlesource.com/66470
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-10-11 23:03:47 +00:00
Hugues Bruant
4f70a2a699 cmd/compile: inline calls to local closures
Calls to a closure held in a local, non-escaping,
variable can be inlined, provided the closure body
can be inlined and the variable is never written to.

The current implementation has the following limitations:

 - closures with captured variables are not inlined because
   doing so naively triggers invariant violation in the SSA
   phase
 - re-assignment check is currently approximated by checking
   the Addrtaken property of the variable which should be safe
   but may miss optimization opportunities if the address is
   not used for a write before the invocation

Updates #15561

Change-Id: I508cad5d28f027bd7e933b1f793c14dcfef8b5a1
Reviewed-on: https://go-review.googlesource.com/65071
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Hugues Bruant <hugues.bruant@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
2017-10-11 22:32:36 +00:00
Austin Clements
44d9e96da9 runtime: don't try to free OS-created signal stacks
Android's libc creates a signal stack for every thread it creates. In
Go, minitSignalStack picks up this existing signal stack and puts it
in m.gsignal.stack. However, if we later try to exit a thread (because
a locked goroutine is exiting), we'll attempt to stackfree this
libc-allocated signal stack and panic.

Fix this by clearing gsignal.stack when we unminitSignals in such a
situation.

This should fix the Android build, which is currently broken.

Change-Id: Ieea8d72ef063d22741c54c9daddd8bb84926a488
Reviewed-on: https://go-review.googlesource.com/70130
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-11 22:17:30 +00:00
Joe Tsai
a3e013b082 encoding/json: use Deprecated markers
In #10909, it was decided that "Deprecated:" is a magic string for
tools (e.g., #17056 for godoc) to detect deprecated identifiers.
Use those convention instead of custom written prose.

Change-Id: Ia514fc3c88fc502e86c6e3de361c435f4cb80b22
Reviewed-on: https://go-review.googlesource.com/70110
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
2017-10-11 22:09:22 +00:00
David Chase
edcf2d0cd6 cmd/compile: add line numbers to values & blocks in ssa.html
In order to improve the line numbering for debuggers,
it's necessary to trace lines through compilation.
This makes it (much) easier to follow.

The format of the last column of the ssa.html output was
also changed to reduce the spamminess of the file name,
which is usually the same and makes it far harder to read
instructions and line numbers, and to make it wider and also
able to break words when wrapping (long path names still
can push off the end otherwise; side-to-side scrolling was
tried but was more annoying than the occasional wrapped
line).

Sample output now, where [...] is elision for sake of making
the CL character-counter happy -- and the (##) line numbers
are rendered in italics and a smaller font (11 point) under
control of a CSS class "line-number".

genssa
      # /Users/drchase/[...]/ssa/testdata/hist.go
      00000 (35) TEXT	"".main(SB)
      00001 (35) FUNCDATA	$0, gclocals·7be4bb[...]1e8b(SB)
      00002 (35) FUNCDATA	$1, gclocals·9ab98a[...]4568(SB)
v920  00003 (36) LEAQ	""..autotmp_31-640(SP), DI
v858  00004 (36) XORPS	X0, X0
v6    00005 (36) LEAQ	-48(DI), DI
v6    00006 (36) DUFFZERO	$277
v576  00007 (36) LEAQ	""..autotmp_31-640(SP), AX
v10   00008 (36) TESTB	AX, (AX)
b1    00009 (36) JMP	10

and from an earlier phase:

b18: ← b17
v242 (47) = Copy <mem> v238
v243 (47) = VarKill <mem> {.autotmp_16} v242
v244 (48) = Addr <**bufio.Scanner> {scanner} v2
v245 (48) = Load <*bufio.Scanner> v244 v243
[...]
v279 (49) = Store <mem> {int64} v277 v276 v278
v280 (49) = Addr <*error> {.autotmp_18} v2
v281 (49) = Load <error> v280 v279
v282 (49) = Addr <*error> {err} v2
v283 (49) = VarDef <mem> {err} v279
v284 (49) = Store <mem> {error} v282 v281 v283
v285 (47) = VarKill <mem> {.autotmp_18} v284
v286 (47) = VarKill <mem> {.autotmp_17} v285
v287 (50) = Addr <*error> {err} v2
v288 (50) = Load <error> v287 v286
v289 (50) = NeqInter <bool> v288 v51
If v289 → b21 b22 (line 50)

Change-Id: I3f46310918f965761f59e6f03ea53067237c28a8
Reviewed-on: https://go-review.googlesource.com/69591
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-10-11 21:46:20 +00:00
Ian Lance Taylor
30cb30e596 runtime: unify amd64 -buildmode=c-archive/c-shared entry point code
This adds the _lib entry point to various GOOS_amd64.s files.
A future CL will enable c-archive/c-shared mode for those targets.

As far as I can tell, the newosproc0 function in os_darwin.go was
passing the wrong arguments to bsdthread_create. The newosproc0
function is never called in the current testsuite.

Change-Id: Ie7c1c2e326cec87013e0fea84f751091b0ea7f51
Reviewed-on: https://go-review.googlesource.com/69711
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2017-10-11 21:12:51 +00:00
Lynn Boger
c15c44ec48 misc/cgo/testcarchive: use -no-pie where needed
Starting in gcc 6, -pie is passed to the linker by default
on some platforms, including ppc64le. If the objects
being linked are not built for -pie then in some cases the
executable could be in error. To avoid that problem, -no-pie
should be used with gcc to override the default -pie option
and generate a correct executable that can be run without error.

Fixes #22126

Change-Id: I4a052bba8b9b3bd6706f5d27ca9a7cebcb504c95
Reviewed-on: https://go-review.googlesource.com/70072
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-11 21:01:45 +00:00
David Crawshaw
ecfa7375e4 cmd/link: move ELF reader to its own package
Along the way, switch to using relocation constants from debug/elf.

For #22095

Change-Id: I1a64353619f95dde5aa39060c4b9d001af7dc1e4
Reviewed-on: https://go-review.googlesource.com/69013
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-11 20:53:39 +00:00
Cherry Zhang
70576947fd test: skip issue22200b.go on mipsle
It should be skipped on 32-bit architectures.

Change-Id: If7a64b9e90e47c3e8734dd62729bfd2944ae926c
Reviewed-on: https://go-review.googlesource.com/70071
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
2017-10-11 20:37:23 +00:00
Russ Cox
d19ced040a cmd/dist: refresh deps.go after recent package io changes
Change-Id: Iaa960c85011289e047c64b53cf610838eb50332d
Reviewed-on: https://go-review.googlesource.com/70073
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2017-10-11 20:31:38 +00:00
Ian Lance Taylor
cf3f771203 runtime: unify amd64 -buildmode=exe entry point code
All of the amd64 entry point code is the same except for Plan 9.
Unify it all into asm_amd64.s.

Change-Id: Id47ce3a7bb2bb0fd48f326a2d88ed18b17dee456
Reviewed-on: https://go-review.googlesource.com/69292
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-11 20:07:31 +00:00
Austin Clements
e29efbcbcb cmd/link: fix some unintentional symbol creation
There are two places in DWARF generation that create symbols when they
really just want to get the symbol if it exists. writeranges, in
particular, will create a DWARF range symbol for every single textp
symbol (though they won't get linked into any list, so they don't
affect the binary).

Fix these to use ROLookup instead of Lookup.

Change-Id: I401eadf22890e296bd08bccaa6ba2fd8fac800cd
Reviewed-on: https://go-review.googlesource.com/69971
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
2017-10-11 20:06:41 +00:00
Joe Tsai
371eda4558 io: simplify pipe implementation
In the distant past, Pipe was implemented with channels and a
long running pipe.run goroutine (see CL 994043).
This approach of having all communication serialized through the
run method was error prone giving Pipe a history of deadlocks
and race conditions.

After the introduction of sync.Cond, the implementation was rewritten
(see CL 4252057) to use condition variables and avoid the
long running pipe.run goroutine. While this implementation is superior
to the previous one, this implementation is strange in that the
p.data field is always set immediately prior to signaling the other
goroutine with Cond.Signal, effectively making the combination of the
two a channel-like operation. Inferior to a channel, however, this still
requires explicit locking around the p.data field.

The data+rwait can be effectively be replaced by a "chan []byte" to
inform a reader that there is data available.
The data+wwait can be effectively be replaced by a "chan int" to
inform a writer of how many bytes were read.

This implementation is a simplified from net.Pipe in CL 37402.

Change-Id: Ia5b26320b0525934fd87a3b69a091c787167f5aa
Reviewed-on: https://go-review.googlesource.com/65330
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
2017-10-11 20:00:54 +00:00
Joe Tsai
e2dd8ca946 net: implement deadline functionality on Pipe
Implement deadline functionality on Pipe so that it properly implements
the semantics of the Conn interface. This aids usages of Pipe (often in
unit tests) with a more realistic and complete implementation.

The new implementation avoids a dependency on a io.Pipe since it is
impossible to keep the prior semantics of synchronous reads and writes
while also trying to implement cancelation over an io.{Reader,Writer}
that fundamentally has no cancelation support.

The fact that net.Pipe is synchronous (and documented as such)
is unfortunate because no realistic network connection is synchronous.
Instead real networks introduces a read and write buffer of some sort.
However, we do not change the semantics for backwards compatibility.

The approach taken does not leave any long-running goroutines,
meaning that tests that never call Close will not cause a resource leak.

Fixes #18170

Change-Id: I5140b1f289a0a49fb2d485f031b5aa0ee99ecc30
Reviewed-on: https://go-review.googlesource.com/37402
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-11 20:00:52 +00:00
Russ Cox
7dcd33302a cmd/internal/buildid: add missing f.Close in ReadFile
On Windows, not closing f keeps us from being able to remove it.

Change-Id: Id4cb709b6ce0b30485b87364a9f0e6e71d2782bd
Reviewed-on: https://go-review.googlesource.com/70070
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-11 19:38:04 +00:00
Russ Cox
31896332b3 cmd/dist: reenable TestDeps
It looks like I forgot to reenable this test when I fixed #21522.
Update deps.go and reenable.

Change-Id: I68a45df09b418f48d93d2e7ab1d274e056c192e6
Reviewed-on: https://go-review.googlesource.com/70050
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-11 19:10:31 +00:00
Russ Cox
cdbc363cb2 cmd/go: record both build ID and content ID in archives and binaries
The content ID will be needed for content-based staleness
determination. It is defined as the SHA256 hash of the file
in which it appears, with occurrences of the build+content IDs
changed to zeros during the hashing operation.

Storing the content ID in the archives is a little tricky
but it means that later builds need not rehash the archives
each time they are referenced, so under the assumption
that each package is imported at least once after being
compiled, hashing at build time is a win. (Also the whole
file is more likely to be in cache at build time,
since we just wrote it.)

In my unscientific tests, the time for "go build -a std cmd"
rises from about 14.3s to 14.5s on my laptop, or under 2%.

Change-Id: Ia3d4dc657d003e8295631f73363868bd92ebf96a
Reviewed-on: https://go-review.googlesource.com/69054
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-11 19:03:26 +00:00
Austin Clements
85f93c889a cmd/compile: fix some plive comments
The liveness analysis no longer directly emits PCDATA. Fix stale
comments that say so.

Change-Id: Id26b112ddf4c13a12ebf766f64bf57c68fbfe3ef
Reviewed-on: https://go-review.googlesource.com/67691
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-10-11 18:29:36 +00:00
Keith Randall
e130dcf051 cmd/compile: abort earlier if stack frame too large
If the stack frame is too large, abort immediately.
We used to generate code first, then abort.
In issue 22200, generating code raised a panic
so we got an ICE instead of an error message.

Change the max frame size to 1GB (from 2GB).
Stack frames between 1.1GB and 2GB didn't used to work anyway,
the pcln table generation would have failed and generated an ICE.

Fixes #22200

Change-Id: I1d918ab27ba6ebf5c87ec65d1bccf973f8c8541e
Reviewed-on: https://go-review.googlesource.com/69810
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-11 18:24:13 +00:00
Keith Randall
624630b824 cmd/compile: fold constant comparisions into SETxxmem ops.
Fixes #22198

Change-Id: I5cb91c73069af8b16a2580d28756efd58c84b690
Reviewed-on: https://go-review.googlesource.com/69990
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-10-11 18:23:09 +00:00
Russ Cox
9ad2319bbc cmd/buildid: add new tool factoring out code needed by go command
This CL does a few things.

1. It moves the existing "read a build ID" code out of the go command
and into cmd/internal/buildid.

2. It adds new code there to "write a build ID".

3. It adds better tests.

4. It encapsulates cmd/internal/buildid into a new standalone program
"go tool buildid".

The go command is going to use the new "write a build ID" functionality
in a future CL. Adding the separate "go tool buildid" gives "go build -x"
a printable command to explain what it is doing in that new step.
(This is similar to the go command printing "go tool pack" commands
equivalent to the actions it is taking, even though it's not invoking pack
directly.) Keeping go build -x honest means that other build systems can
potentially keep up with the go command.

Change-Id: I01c0a66e30a80fa7254e3f2879283d3cd7aa03b4
Reviewed-on: https://go-review.googlesource.com/69053
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-11 18:16:02 +00:00
Austin Clements
0bede7f34e cmd/compile: split TestNexting into subtests
This makes it more obvious which of the two builds is failing by
putting "dbg" or "opt" directly in the test name. It also makes it
possible for them to fail independently, so a failure in "dbg" doesn't
mask a failure in "opt", and to visibly skip the opt test when run
with an unoptimized runtime.

Change-Id: I3403a7fd3c1a13ad51a938bb95dfe54c320bb58e
Reviewed-on: https://go-review.googlesource.com/69970
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
2017-10-11 17:53:10 +00:00
Austin Clements
0aef82aa4a runtime: make (Un)LockOSThread doc more prescriptive
Right now users have to infer why they would want LockOSThread and
when it may or may not be appropriate to call UnlockOSThread. This
requires some understanding of Go's internal thread pool
implementation, which is unfortunate.

Improve the situation by making the documentation on these functions
more prescriptive so users can figure out when to use them even if
they don't know about the scheduler.

Change-Id: Ide221791e37cb5106dd8a172f89fbc5b3b98fe32
Reviewed-on: https://go-review.googlesource.com/52871
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-10-11 17:47:23 +00:00
Austin Clements
4f34a52913 runtime: terminate locked OS thread if its goroutine exits
runtime.LockOSThread is sometimes used when the caller intends to put
the OS thread into an unusual state. In this case, we never want to
return this thread to the runtime thread pool. However, currently
exiting the goroutine implicitly unlocks its OS thread.

Fix this by terminating the locked OS thread when its goroutine exits,
rather than simply returning it to the pool.

Fixes #20395.

Change-Id: I3dcec63b200957709965f7240dc216fa84b62ad9
Reviewed-on: https://go-review.googlesource.com/46038
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-10-11 17:47:21 +00:00
Austin Clements
eff2b2620d runtime: make it possible to exit Go-created threads
Currently, threads created by the runtime exist until the whole
program exits. For #14592 and #20395, we want to be able to exit and
clean up threads created by the runtime. This commit implements that
mechanism.

The main difficulty is how to clean up the g0 stack. In cgo mode and
on Solaris and Windows where the OS manages thread stacks, we simply
arrange to return from mstart and let the system clean up the thread.
If the runtime allocated the g0 stack, then we use a new exitThread
syscall wrapper that arranges to clear a flag in the M once the stack
can safely be reaped and call the thread termination syscall.

exitThread is based on the existing exit1 wrapper, which was always
meant to terminate the calling thread. However, exit1 has never been
used since it was introduced 9 years ago, so it was broken on several
platforms. exitThread also has the additional complication of having
to flag that the stack is unused, which requires some tricks on
platforms that use the stack for syscalls.

This still leaves the problem of how to reap the unused g0 stacks. For
this, we move the M from allm to a new freem list as part of the M
exiting. Later, allocm scans the freem list, finds Ms that are marked
as done with their stack, removes these from the list and frees their
g0 stacks. This also allows these Ms to be garbage collected.

This CL does not yet use any of this functionality. Follow-up CLs
will. Likewise, there are no new tests in this CL because we'll need
follow-up functionality to test it.

Change-Id: Ic851ee74227b6d39c6fc1219fc71b45d3004bc63
Reviewed-on: https://go-review.googlesource.com/46037
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-10-11 17:47:18 +00:00
Russ Cox
a9c3d09d0e cmd/go: make cmd/* default to go tool installation
Every cmd/thing is 'go tool thing' except for go and gofmt.
But the table in cmd/go enumerates all the things instead of
saying that go and gofmt are the exceptions.
Change that, so that when adding new tools it's not
necessary to update this table.

Change-Id: Ia6fef41b4d967249b19971a0d03e5acb0317ea82
Reviewed-on: https://go-review.googlesource.com/69052
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-11 17:47:17 +00:00