When the compiler insert write barriers, the frontend makes
conservative decisions at an early stage. This may have false
positives which result in write barriers for stack writes.
A new phase, writebarrier, is added to the SSA backend, to delay
the decision and eliminate false positives. The frontend still
makes conservative decisions. When building SSA, instead of
emitting runtime calls directly, it emits WB ops (StoreWB,
MoveWB, etc.), which will be expanded to branches and runtime
calls in writebarrier phase. Writes to static locations on stack
are detected and write barriers are removed.
All write barriers of stack writes found by the script from
issue #17330 are eliminated (except two false positives).
Fixes#17330.
Change-Id: I9bd66333da9d0ceb64dcaa3c6f33502798d1a0f8
Reviewed-on: https://go-review.googlesource.com/31131
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
The runtime traceback code assumes non-empty frame has link
link register saved on LR architectures. Make sure it is so in
the assember.
Also make sure that LR is stored before update SP, so the traceback
code will not see a half-updated stack frame if a signal comes
during the execution of function prologue.
Fixes#17381.
Change-Id: I668b04501999b7f9b080275a2d1f8a57029cbbb3
Reviewed-on: https://go-review.googlesource.com/31760
Reviewed-by: Michael Munday <munday@ca.ibm.com>
Update the ppc64x disassembly code for use by objdump
from golang.org/x/arch/ppc64/ppc64asm commit fcea5ea.
Enable the objdump testcase for external linking on ppc64le
make a minor fix to the expected output.
Fixes#17447
Change-Id: I769cc7f8bfade594690a476dfe77ab33677ac03b
Reviewed-on: https://go-review.googlesource.com/32015
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The Dragonfly libc returns a non-zero value for malloc(-1).
Fixes#17585.
Change-Id: Icfe68011ccbc75c676273ee3c3efdf24a520a004
Reviewed-on: https://go-review.googlesource.com/32050
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
For historical reasons, the go/doc package does not include
the methods within an interface as part of the documented
methods for that type. Thus,
go doc ast.Node.Pos
gives an incorrect and confusing error message:
doc: no method Node.Pos in package go/ast
This CL does some dirty work to dig down to the methods
so interface methods now present their documentation:
% go doc ast.node.pos
func Pos() token.Pos // position of first character belonging to the node
%
It must largely sidestep the doc package to do this, which
is a shame. Perhaps things will improve there one day.
The change does not handle embeddings, and in principle the
same approach could be done for struct fields, but that is also
not here yet. But this CL fixes the thing that was bugging me.
Change-Id: Ic10a91936da96f54ee0b2f4a4fe4a8c9b93a5b4a
Reviewed-on: https://go-review.googlesource.com/31852
Reviewed-by: Robert Griesemer <gri@golang.org>
Instead of generating typelink symbols in the compiler
mark types that should have typelinks with a flag.
The linker detects this flag and adds the marked types
to the typelink table.
name old s/op new s/op delta
LinkCmdCompile 0.27 ± 6% 0.25 ± 6% -6.93% (p=0.000 n=97+98)
LinkCmdGo 0.30 ± 5% 0.29 ±10% -4.22% (p=0.000 n=97+99)
name old MaxRSS new MaxRSS delta
LinkCmdCompile 112k ± 3% 106k ± 2% -4.85% (p=0.000 n=100+100)
LinkCmdGo 107k ± 3% 103k ± 3% -3.00% (p=0.000 n=100+100)
Change-Id: Ic95dd4b0101e90c1fa262c9c6c03a2028d6b3623
Reviewed-on: https://go-review.googlesource.com/31772
Run-TryBot: Shahar Kohanim <skohanim@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
The condition to determine if any further iterations are needed is
evaluated to false in case it encounters a NaN. Instead, flip the
condition to keep looping until the factor is greater than the machine
roundoff error.
Updates #17577
Change-Id: I058abe73fcd49d3ae4e2f7b33020437cc8f290c3
Reviewed-on: https://go-review.googlesource.com/31952
Reviewed-by: Robert Griesemer <gri@golang.org>
In sinit.go, gdata can already handle strings and complex, so no
reason to handle them separately.
In obj.go, inline gdatastring and gdatacomplex into gdata, since it's
the only caller. Allows extracting out the common Linksym calls.
Passes toolstash -cmp.
Change-Id: I3cb18d9b4206a8a269c36e0d30a345d8e6caba1f
Reviewed-on: https://go-review.googlesource.com/31498
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Bug 15141 was apparently fixed by some other change to the
compiler (this is plausible, it was a weird bug dependent
on a particular way of returning a large named array result),
add the test to ensure that it stays fixed.
Updates #15141.
Change-Id: I3d6937556413fab1af31c5a1940e6931563ce2f3
Reviewed-on: https://go-review.googlesource.com/31972
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
It no longer exists as of CL 31010.
Change-Id: Idd61f392544cad8b3f3f8d984dc5c953b473e2e5
Reviewed-on: https://go-review.googlesource.com/31934
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Some original shift opcodes for ppc64x expected an operand to be
a mask instead of a shift count, preventing some valid shift counts
from being written.
This adds new opcodes for shifts where needed, using mnemonics that
match the ppc64 asm and allowing the assembler to accept the full set
of valid shift counts.
Fixes#15016
Change-Id: Id573489f852038d06def279c13fd0523736878a7
Reviewed-on: https://go-review.googlesource.com/31853
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Carlos Eduardo Seo <cseo@linux.vnet.ibm.com>
Reviewed-by: David Chase <drchase@google.com>
These are emulated by the assembler and we don't need them.
Change-Id: I2b07c5315a5b642fdb5e50b468453260ae121164
Reviewed-on: https://go-review.googlesource.com/31758
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Before go supported buildmode=shared ·f symbols used to be defined
only when they were used. In order to solve #11480 the strategy
was changed to have these symbols defined on declaration which is
less efficient and generates many unneeded symbols.
With this change the best strategy is chosen for each situation,
improving static linking time:
name old s/op new s/op delta
LinkCmdCompile 0.27 ± 5% 0.25 ± 6% -8.22% (p=0.000 n=98+96)
LinkCmdGo 0.30 ± 6% 0.29 ± 8% -5.03% (p=0.000 n=95+99)
name old MaxRSS new MaxRSS delta
LinkCmdCompile 107k ± 2% 98k ± 3% -8.32% (p=0.000 n=99+100)
LinkCmdGo 106k ± 3% 104k ± 3% -1.94% (p=0.000 n=99+100)
Change-Id: I965eeee30541e724fd363804adcd6fda10f965a4
Reviewed-on: https://go-review.googlesource.com/31031
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
In general, these functions cannot behave correctly when given a
hostname, because a hostname may represent multiple IP addresses, and
first(isIPv4) chooses at most one.
Updates #9334
Change-Id: Icfb629f84af4d976476385a3071270253c0000b1
Reviewed-on: https://go-review.googlesource.com/31931
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Looking at the kernel sources, I don't see how this is possible.
But obviously it is. Just try again.
Fixes#17161.
Change-Id: Iea7d53f7cf75944792d2f75a0d07129831c7bcdb
Reviewed-on: https://go-review.googlesource.com/31823
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The old code leaves garbages in a temporary directory because it
cannot remove the current working directory on windows.
The new code changes the directory before calling os.Remove.
Furthermore, the old code assumes that ioutil.TempDir (os.TempDir)
doesn't return a relative path nor an UNC path.
If it isn't the case, the new code calls t.Fatal earlier for preventing
ambiguous errors.
Finally, the old code reassigns the variable which is used by the defer
function. It could cause unexpected results, so avoid that.
Change-Id: I5fc3902059ecaf18dc1341ecc4979d1206034cd7
Reviewed-on: https://go-review.googlesource.com/31790
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Updates #15345
Change-Id: I447d133512e99a9900928a910e161a85db6e8b75
Reviewed-on: https://go-review.googlesource.com/31792
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
It appears to be a vestigial holding ground for bugs.
But we have an issue tracker, and #1909 is there and open.
Change-Id: I912ff222a24c51fab483be0c67dad534f5a84488
Reviewed-on: https://go-review.googlesource.com/31859
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
CL 31468 added TestLookupNonLDH, which was failing on Plan 9,
because LookupHost was expecting to return errNoSuchHost
on DNS resolution failure, while Plan 9 returned the
"dns failure" string.
In the Plan 9 implementation of lookupHost, we now return
errNoSuchHost instead of the "dns failure" string, so
the behavior is more consistant with other operating systems.
Fixes#17568.
Change-Id: If64f580dc0626a4a4f19e5511ba2ca5daff5f789
Reviewed-on: https://go-review.googlesource.com/31873
Run-TryBot: David du Colombier <0intro@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
VerifyPeerCertificate returns an error if the peer should not be
trusted. It will be called after the initial handshake and before
any other verification checks on the cert or chain are performed.
This provides the callee an opportunity to augment the certificate
verification.
If VerifyPeerCertificate is not nil and returns an error,
then the handshake will fail.
Fixes#16363
Change-Id: I6a22f199f0e81b6f5d5f37c54d85ab878216bb22
Reviewed-on: https://go-review.googlesource.com/26654
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This prevents the traceback code from seeing a half-updated
stack frame when a profiling signal comes during the execution
of function prologue. Also fixes mips64x part of #17381.
Change-Id: Iec9683427e546e3648b2e8b1dde956d13f6eb938
Reviewed-on: https://go-review.googlesource.com/31721
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Since CL 30614, TestCloseError is failing on Plan 9,
because File.Write now checks f.fd == badFd before
calling syscall.Write.
The f.fd == badFd check returns os.ErrClosed, while
syscall.Write returned a syscall.ErrorString error.
TestCloseError was failing because it expected a
syscall.ErrorString error.
We add a case in parseCloseError to handle the
os.ErrClosed case.
Fixes#17569.
Change-Id: I6b4d956d18ed6d3c2ac5211ffd50a4888f7521e1
Reviewed-on: https://go-review.googlesource.com/31872
Run-TryBot: David du Colombier <0intro@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Adds a rule to generate ANDN for AND x ^y.
Fixes#17567
Change-Id: I3b978058d5663f32c42b1af19bb207eac5622615
Reviewed-on: https://go-review.googlesource.com/31769
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
The Gotype field is only used for ATYPE instructions. Instead of
specially storing the Go type symbol in From.Gotype, just store it in
To.Sym like any other 2-argument instruction would.
Modest reduction in allocations:
name old alloc/op new alloc/op delta
Template 42.0MB ± 0% 41.8MB ± 0% -0.40% (p=0.000 n=9+10)
Unicode 34.3MB ± 0% 34.1MB ± 0% -0.48% (p=0.000 n=9+10)
GoTypes 122MB ± 0% 122MB ± 0% -0.14% (p=0.000 n=9+10)
Compiler 518MB ± 0% 518MB ± 0% -0.04% (p=0.000 n=9+10)
Passes toolstash -cmp.
Change-Id: I0e603266b5d7d4e405106a26369e22773a0d3a91
Reviewed-on: https://go-review.googlesource.com/31850
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
