Instead of relying on the asm names declared in the gccgo version of
cgo_export.h, just emit a dummy symbol with the right asm name. This
is enough to let the _cgo_main link succeed, which is all that matters
here.
Fixes#9294.
Change-Id: I803990705b6b226ed0adf17dc57b58a9f501b213
Reviewed-on: https://go-review.googlesource.com/1901
Reviewed-by: Minux Ma <minux@golang.org>
Previously, liblink would silently truncate register offset constants
to 32 bits. For example,
MOVD $0x200000004(R2),R3
would assemble to
addis r31,r2,0
addi r3,r31,4
To fix this, limit C_LACON to 32 bit (signed) offsets and introduce a
new C_DACON operand type for larger register offsets. We don't
implement this currently, but at least liblink will now give an error
if it encounters an address like this.
Change-Id: I8e87def8cc4cc5b75498b0fb543ac7666cf2964e
Reviewed-on: https://go-review.googlesource.com/1758
Reviewed-by: Minux Ma <minux@golang.org>
On ppc64, there are three ELF ABI versions an ELF file can request.
Previously, we used 0, which means "unspecified". On our test
machines, this meant to use the default (v1 for big endian and v2 for
little endian), but apparently some systems can pick the wrong ABI if
neither is requested. Leaving this as 0 also confuses libbfd, which
confuses gdb, objdump, etc.
Fix these problems by specifying ABI v1 for big endian and v2 for
little endian.
Change-Id: I4d3d5478f37f11baab3681a07daff3da55802322
Reviewed-on: https://go-review.googlesource.com/1800
Reviewed-by: Minux Ma <minux@golang.org>
When we do y = &x for global variables x and y, y gets initialized
at link time. Do the same for y = &x.f if x is a struct and y=&x[5]
if x is an array.
fixes#9217fixes#9355
Change-Id: Iea3c0ce2ce1b309e2b760e345608fd95460b5713
Reviewed-on: https://go-review.googlesource.com/1691
Reviewed-by: Minux Ma <minux@golang.org>
On ppc64, liblink rewrites MOVD's of >32-bit constants by putting the
constant in memory and rewriting the MOVD to load from that memory
address. However, there were two bugs in the condition:
a) owing to an incorrect sign extension, it triggered for all negative
constants, and
b) it could trigger for constant offsets from registers (addresses of
the form $n(Rm) in assembly)
Together, these meant instructions of the form MOVD $-n(Rm), x were
compiled by putting -n in memory and rewriting the MOVD to load this
constant from memory (completely dropping Rm).
Change-Id: I1f6cc980efa3e3d6f164b46c985b2c3b55971cca
Reviewed-on: https://go-review.googlesource.com/1752
Reviewed-by: Minux Ma <minux@golang.org>
People are probably not making this mistake anymore.
Fixes#9164
Change-Id: I86b440ed63d09b4ca676bba7034838860f1a5d8b
Reviewed-on: https://go-review.googlesource.com/1782
Reviewed-by: Minux Ma <minux@golang.org>
Most types are reflexive (k == k for all k of type t), so don't
bother calling equal(k, k) when the key type is reflexive.
Change-Id: Ia716b4198b8b298687843b94b878dbc5e8fc2c65
Reviewed-on: https://go-review.googlesource.com/1480
Reviewed-by: Russ Cox <rsc@golang.org>
Remove carriage returns from //go:generate lines.
Carriage returns are the predecessor of BOMs and still
live on Windows.
Fixes#9264
Change-Id: I637748c74335c696b3630f52f2100061153fcdb4
Reviewed-on: https://go-review.googlesource.com/1564
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>
//go:nowritebarrier can only be used in package runtime.
It does not disable write barriers; it is an assertion, checked
by the compiler, that the following function needs no write
barriers.
Change-Id: Id7978b779b66dc1feea39ee6bda9fd4d80280b7c
Reviewed-on: https://go-review.googlesource.com/1224
Reviewed-by: Rick Hudson <rlh@golang.org>
Still using the ancient go/types API. Updating that to the modern API
should be a separate effort in a separate change.
Change-Id: Ic1c5ae3c13711d34fe757507ecfc00ee883810bf
Reviewed-on: https://go-review.googlesource.com/1404
Reviewed-by: David Symonds <dsymonds@golang.org>
We forgot to do the usual API review.
Make that not possible in the future.
I'll pull this change over to the main
branch too, but it's more important
(and only testable) here.
LGTM=bradfitz
R=bradfitz
CC=golang-codereviews
https://golang.org/cl/185050043
I read through and vetted these but others should look too.
LGTM=bradfitz, adg
R=r, minux, bradfitz, adg
CC=adg, golang-codereviews, gri, iant
https://golang.org/cl/182560043
This flag no longer exists. It has been replaced with -unit=byte.
Change-Id: Iff9fc501f2c666067c9b1948c4623c8e3adddb8d
Reviewed-on: https://go-review.googlesource.com/1287
Reviewed-by: Russ Cox <rsc@golang.org>
Avoids a potential O(n^2) performance problem when dequeueing
from very popular channels.
benchmark old ns/op new ns/op delta
BenchmarkChanPopular 2563782 627201 -75.54%
Change-Id: I231aaeafea0ecd93d27b268a0b2128530df3ddd6
Reviewed-on: https://go-review.googlesource.com/1200
Reviewed-by: Russ Cox <rsc@golang.org>
When we start work on Gerrit, ppc64 and garbage collection
work will continue in the master branch, not the dev branches.
(We may still use dev branches for other things later, but
these are ready to be merged, and doing it now, before moving
to Git means we don't have to have dev branches working
in the Gerrit workflow on day one.)
TBR=rlh
CC=golang-codereviews
https://golang.org/cl/183140043
This is the last system-dependent file written by cmd/dist.
They are all now written by go generate.
cmd/dist is not needed to start building package runtime
for a different system anymore.
Now all the generated files can be assumed generated, so
delete the clumsy hacks in cmd/api.
Re-enable api check in run.bash.
LGTM=bradfitz
R=bradfitz
CC=golang-codereviews
https://golang.org/cl/185040044
Frankly, I don't understand how the current code could possibly work except
when every android program is using cgo. Discovered this while working on
the iOS port.
LGTM=crawshaw, rsc
R=rsc, crawshaw
CC=golang-codereviews
https://golang.org/cl/177470043
The new semantics of split require the newline be present.
The test was stale.
LGTM=adg
R=golang-codereviews, adg
CC=golang-codereviews
https://golang.org/cl/182480043
Scanner can't handle stupid long lines and there are
reports of stupid long lines in production.
Note the issue isn't long "//go:generate" lines, but
any long line in any Go source file.
To be fair, if you're going to have a stupid long line
it's not a bad bet you'll want to run it through go
generate, because it's some embeddable asset that
has been machine generated. (One could ask why
that generation process didn't add a newline or two,
but we should cope anyway.)
Rewrite the file scanner in "go generate" so it can
handle arbitrarily long lines, and only stores in memory
those lines that start "//go:generate".
Also: Adjust the documentation to make clear that it
does not parse the file.
Fixes#9143.
Fixes#9196.
LGTM=rsc, dominik.honnef
R=rsc, cespare, minux, dominik.honnef
CC=golang-codereviews
https://golang.org/cl/182970043
While we're at there, also add a message to prompt the user to install
Graphviz if "dot" command is not found.
Fixes#9178.
LGTM=adg, alex.brainman, cookieo9, rsc
R=rsc, adg, bradfitz, alex.brainman, cookieo9, smyrman
CC=golang-codereviews
https://golang.org/cl/180380043
Move change from CL 170770043 to correct file and regenerate docs
for changes from CL 164120043.
LGTM=adg
R=golang-codereviews, adg, bradfitz
CC=golang-codereviews
https://golang.org/cl/183000043
These accomplished the same thing, but R_CALLPOWER expected
the whole instruction to be in the addend (and completely
overwrote what was in the text section), while R_PPC64_REL24
overwrites only bits 6 through 24 of whatever was in the text
section. Make R_CALLPOWER work like R_PPC64_REL24 to ease the
implementation of dynamic linking.
LGTM=rsc
R=rsc
CC=golang-codereviews, minux
https://golang.org/cl/177430043
warning: src/cmd/5g/reg.c:461 format mismatch d VLONG, arg 5
warning: src/cmd/6g/reg.c:396 format mismatch d VLONG, arg 5
warning: src/cmd/9g/reg.c:440 format mismatch d VLONG, arg 5
LGTM=minux
R=rsc, minux
CC=golang-codereviews
https://golang.org/cl/179300043
This was based on the 9c peephole optimizer, modified to work
with code generated by gc and use the proginfo infrastructure
in gc.
LGTM=rsc
R=rsc, bradfitz, minux
CC=golang-codereviews
https://golang.org/cl/179190043
This adds some utilities for converting between the CC, V, and
VCC variants of operations and uses these to derive the
ProgInfo entries for these variants (which are identical to
the ProgInfo for the base operations).
The 9g peephole optimizer will also use these conversion
utilities.
LGTM=minux, rsc
R=rsc, dave, minux
CC=golang-codereviews
https://golang.org/cl/180110044
Previously, 9a was the only assembler that had a different
name for RET, causing unnecessary friction in simple files
that otherwise assembled on all architectures. Add RET so
these work on 9a.
This also renames "R30" to "g" to avoid unintentionally
clobbering g in assembly code. This parallels a change made
to 5a.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/178030043
Eventually I'd like almost everything cmd/dist generates
to be done with 'go generate' and checked in, to simplify
the bootstrap process. The only thing cmd/dist really needs
to do is write things like the current experiment info and
the current version.
This is a first step toward that. It replaces the _NaCl etc
constants with generated ones goos_nacl, goos_darwin,
goarch_386, and so on.
LGTM=dave, austin
R=austin, dave, bradfitz
CC=golang-codereviews, iant, r
https://golang.org/cl/174290043
getFunctionSource gathers five lines of "margin" around every
requested sample line. However, if this margin went past the
end of the source file, getFunctionSource would encounter an
io.EOF error and abort with this error, resulting in listings
like
(pprof) list main.main
ROUTINE ======================== main.main in ...
0 8.33s (flat, cum) 99.17% of Total
Error: EOF
(pprof)
Modify the error handling in getFunctionSource so io.EOF is
always considered non-fatal. If it reaches EOF, it simply
returns the lines it has.
LGTM=bradfitz
R=rsc, bradfitz
CC=golang-codereviews
https://golang.org/cl/172600043
debug/goobj is not ready to be published but it is
needed for the various binary-reading commands.
Move to cmd/internal/goobj.
(The Go 1.3 release branch deleted it, but that's not
an option anymore due to the command dependencies.
The API is still not vetted nor terribly well designed.)
LGTM=adg, dsymonds
R=adg, dsymonds
CC=golang-codereviews
https://golang.org/cl/174250043
This change works around the "out of fixed registers"
issue with the Plan 9 C compiler on 386, introduced by
the Bits change to uint64 in CL 169060043.
The purpose of this CL is to be able to properly
follow the conversion of the Plan 9 runtime to Go
on the Plan 9 builders.
This CL could be reverted once the Go compilers will
be converted to Go.
Thanks to Nick Owens for investigating this issue.
LGTM=rsc
R=rsc
CC=austin, golang-codereviews, mischief
https://golang.org/cl/177860043
The garbage collector is now written in Go.
There is plenty to clean up (just like on dev.cc).
all.bash passes on darwin/amd64, darwin/386, linux/amd64, linux/386.
TBR=rlh
R=austin, rlh, bradfitz
CC=golang-codereviews
https://golang.org/cl/173250043
The pretty printers for these make it hard to understand
what's actually in the fields of these structures. These
"ugly printers" show exactly what's in each field, which can
be useful for understanding and debugging code.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/175780043
This is to reduce the delta between dev.cc and dev.garbage to just garbage collector changes.
These are the files that had merge conflicts and have been edited by hand:
malloc.go
mem_linux.go
mgc.go
os1_linux.go
proc1.go
panic1.go
runtime1.go
LGTM=austin
R=austin
CC=golang-codereviews
https://golang.org/cl/174180043
Now the only difference between dev.cc and dev.garbage
is the runtime conversion on the one side and the
garbage collection on the other. They both have the
same set of changes from default and dev.power64.
LGTM=austin
R=austin
CC=golang-codereviews
https://golang.org/cl/172570043
This is more complicated than the other enums because the D_*
enums are full of explicit initializers and repeated values.
This tries its best. (This will get much cleaner once we
tease these constants apart better.)
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/166700043
Theses were very helpful in understanding the regions and
register selection when porting regopt to 9g. Add them to the
other compilers (and improve 9g's successor debug print).
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/174130043
I added several comments to the regopt-related structures when
porting it to 9g. Synchronize those comments back in to the
other compilers.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/175720043
This adds registerization support to 9g equivalent to what the
other compilers have.
LGTM=rsc
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/174980043
None of the other compilers have a tag for this enum.
Cleaning all of this up to use proper types will happen after
the conversion.
LGTM=minux, rsc
R=rsc, minux
CC=golang-codereviews
https://golang.org/cl/166690043
Previously, the 6g and 8g registerizers scanned for used
registers beyond the end of a region being considered for
registerization. This ancient artifact was copied from the C
compilers, where it was probably necessary to track implicitly
used registers. In the Go compilers it's harmless (because it
can only over-restrict the set of available registers), but no
longer necessary because the Go compilers correctly track
register use/set information. The consequences of this extra
scan were (at least) that 1) we would not consider allocating
the AX register if there was a deferproc call in the future
because deferproc uses AX as a return register, so we see the
use of AX, but don't track that AX is set by the CALL, and 2)
we could not consider allocating the DX register if there was
a MUL in the future because MUL implicitly sets DX and (thanks
to an abuse of copyu in this code) we would also consider DX
used.
This commit fixes these problems by nuking this code.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/174110043
For D_OREG addresses, store the used registers in regindex
instead of reguse because they're really part of addressing.
Add implicit register use/set for DUFFZERO/DUFFCOPY.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/174050044
[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]
- Remove references to C compiler directories.
- Remove generation of special header files.
- Remove generation of Go source files from C declarations.
- Compile Go sources before rest of package (was after),
so that Go compiler can write go_asm.h for use in assembly.
- Move TLS information from cmd/dist (was embedding in output)
to src/runtime/go_tls.h, which it can be maintained directly.
LGTM=r
R=r, dave
CC=austin, golang-codereviews, iant, khr
https://golang.org/cl/172960043
[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]
Make gcToolchain.cc return an error (no C compiler!).
Adjust expectations of cgo, now that cgo does not write any C files
(no C compiler!).
For packages with .s files, invoke Go compiler with -asmhdr go_asm.h
so that assembly files can use it. This applies to all packages but is only
needed today by package runtime.
LGTM=r
R=r
CC=austin, golang-codereviews, iant, khr
https://golang.org/cl/171470043
[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]
export.c, lex.c:
Add -asmhdr flag to write assembly header file with struct
field offsets and const values. cmd/dist used to construct this
file by interpreting output from the C compiler.
Generate it from the Go definitions instead.
Also, generate the form we need directly, instead of relying
on cmd/dist for reprocessing.
lex.c, obj.c:
If the C compiler accepted #pragma cgo_xxx, recognize
a directive //go:cgo_xxx instead. The effect is the same as
in the C compiler: accumulate text into a buffer and emit in the
output file, where the linker will find and use it.
lex.c, obj.c:
Accept //go:linkname to control the external symbol name
used for a particular top-level Go variable. This makes it
possible to refer to C symbol names but also symbols from
other packages. It has always been possible to do this from
C and assembly. To drive home the point that this should not
be done lightly, require import "unsafe" in any file containing
//go:linkname.
plive.c, reflect.c, subr.c:
Hard-code that interfaces contain only pointers.
This means code handling multiword values in the garbage
collector and the stack copier can be deleted instead of being
converted. This change is already present in the dev.garbage
branch.
LGTM=r
R=r
CC=austin, golang-codereviews, iant, khr
https://golang.org/cl/169360043
[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]
We changed cgo to write the actual function wrappers in Go
for Go 1.4. The only code left in C output files was the definitions
for pointers to C data and the #pragma cgo directives.
Write both of those to Go outputs instead, using the new
compiler directives introduced in CL 169360043.
(Still generating C files in gccgo mode.)
LGTM=r
R=r
CC=austin, golang-codereviews, iant, khr
https://golang.org/cl/169330045
Let's just do this up front.
This will break the build (here on the dev.cc branch).
The CLs that follow will take care of fixing it.
Leave behind cmd/cc/lexbody and cmd/cc/macbody for the assemblers.
They'll go away later.
LGTM=dave, r
R=r, dave
CC=golang-codereviews
https://golang.org/cl/172170043
This patch is based only on reading the code. I have not
tried to construct a test case.
Fixes#9077.
LGTM=minux
R=minux
CC=golang-codereviews
https://golang.org/cl/172110043
This was a mistake. The cmd/api tool
depends on an old version of go/types.
««« original CL description
cmd/api: use golang.org/x/... import paths
LGTM=bradfitz, rsc
R=rsc, bradfitz
CC=golang-codereviews
https://golang.org/cl/169000043
»»»
TBR=rsc, bradfitz
R=bradfitz, rsc
CC=golang-codereviews
https://golang.org/cl/169320043
This was a mistake; the cmd/api tool
depends on an old version of go/types.
««« original CL description
cmd/api: bump go.tools golden CL hash
TBR=bradfitz
R=rsc
CC=golang-codereviews
https://golang.org/cl/166380043
»»»
TBR=bradfitz, rsc
R=bradfitz, rsc
CC=golang-codereviews
https://golang.org/cl/167430043
Replace a bit-wise AND with a logical one. This happened to
work before because bany returns 0 or 1, but the intent here
is clearly logical (and this makes 5g match with 6g and 8g).
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/172850043
This was missing from CL 167320043.
Happy to apply comments in a followup.
TBR to fix build.
TBR=r
CC=golang-codereviews
https://golang.org/cl/171260043
Moving so that new Go 1.4 pprof can use it.
The old 'GNU objdump workalike' mode for 'go tool objdump'
is now gone, as are the tests for that mode. It was used only
by pre-Go 1.4 pprof. You can still specify an address range on
the command line; you just get the same output format as
you do when dumping the entire binary (without an address
limitation).
LGTM=r
R=r
CC=golang-codereviews, iant
https://golang.org/cl/167320043
For OITAB nodes, 5g's naddr was setting the wrong etype and
failing to set the width of the resulting Addr.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/171220043
9g's naddr was missing assignments to a->width in several
cases, so the optimizer was getting bogus width information.
Add them.
This correct width information also lets us enable the width
check in gins for MOV*.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/167310043
The etype of references to strings was being incorrectly set
to TINT32 on all platforms. Change it to TSTRING. It seems
this doesn't matter for compilation, since x86 uses LEA
instructions to load string addresses and arm and power64
disassemble the string into its constituent pieces (with the
correct types), but it helps when debugging.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/170100043
Previously, mkvar treated, for example, 0(AX) the same as AX.
As a result, a move to an indirect address would be marked as
*setting* the register, rather than just using it, resulting
in unnecessary register moves. Fix this by not producing
variables for indirect addresses.
LGTM=rsc
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/164610043
The test intended to skip direct calls when creating
registerization variables was testing p->to.type instead of
p->to.name, so it always failed, causing regopt to create
unnecessary variables for these names.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/169110043
Now each C printf, Go print, or Go println is guaranteed
not to be interleaved with other calls of those functions.
This should help when debugging concurrent failures.
LGTM=rlh
R=rlh
CC=golang-codereviews
https://golang.org/cl/169120043
So far all of our architectures have had at most 32 registers,
so we've been able to use entry 0 in the Bits uint32 array
directly as a register mask. Power64 has 64 registers, so
this converts Bits to a uint64 array so we can continue to use
entry 0 directly as a register mask on Power64.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/169060043
The check for unknown command line debug flags in gc was
incorrect: the loop over debugtab terminates when it reaches a
nil entry, but it was only reporting an error if the parser
had passed the last entry of debugtab (which it never did).
Fix this by reporting the usage error if the loop reaches a
nil entry.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/166110043
Previously, nilopt was disabled on power64x because it threw
away "seemly random segments of code." Indeed, excise on
power64x failed to preserve the link field, so it excised not
only the requested instruction but all following instructions
in the function. Fix excise to retain the link field while
otherwise zeroing the instruction.
This makes nilopt safe on power64x. It still fails
nilptr3.go's tests for removal of repeated nil checks because
those depend on also optimizing away repeated loads, which
doesn't currently happen on power64x.
LGTM=dave, rsc
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/168120043
All three cases of clearfat were wrong on power64x.
The cases that handle 1032 bytes and up and 32 bytes and up
both use MOVDU (one directly generated in a loop and the other
via duffzero), which leaves the pointer register pointing at
the *last written* address. The generated code was not
accounting for this, so the byte fill loop was re-zeroing the
last zeroed dword, rather than the bytes following the last
zeroed dword. Fix this by simply adding an additional 8 byte
offset to the byte zeroing loop.
The case that handled under 32 bytes was also wrong. It
didn't update the pointer register at all, so the byte zeroing
loop was simply re-zeroing the beginning of region. Again,
the fix is to add an offset to the byte zeroing loop to
account for this.
LGTM=dave, bradfitz
R=rsc, dave, bradfitz
CC=golang-codereviews
https://golang.org/cl/168870043
This CL implements the many multiword write barriers by calling
writebarrierptr, so that only writebarrierptr needs the actual barrier.
In lieu of an actual barrier, writebarrierptr checks that the value
being copied is not a small non-zero integer. This is enough to
shake out bugs where the barrier is being called when it should not
(for non-pointer values). It also found a few tests in sync/atomic
that were being too clever.
This CL adds a write barrier for the memory moved during the
builtin copy function, which I forgot when inserting barriers for Go 1.4.
This CL re-enables some write barriers that were disabled for Go 1.4.
Those were disabled because it is possible to change the generated
code so that they are unnecessary most of the time, but we have not
changed the generated code yet. For safety they must be enabled.
None of this is terribly efficient. We are aiming for correct first.
LGTM=rlh
R=rlh
CC=golang-codereviews
https://golang.org/cl/168770043
This removes a bunch of ugly duplicate code.
The end goal is to factor the disassembly code
into cmd/internal/objfile too, so that pprof can use it,
but one step at a time.
LGTM=r, iant
R=r, alex.brainman, iant
CC=golang-codereviews
https://golang.org/cl/149400043
The goal here is to get the big-endian fixes so that
in some upcoming code movement for write barriers
I don't make them unmergeable.
LGTM=rlh
R=rlh
CC=golang-codereviews
https://golang.org/cl/166890043
goprintf is a printf-like print for Go.
It is used in the code generated by 'defer print(...)' and 'go print(...)'.
Normally print(1, 2, 3) turns into
printint(1)
printint(2)
printint(3)
but defer and go need a single function call to give the runtime;
they give the runtime something like goprintf("%d%d%d", 1, 2, 3).
Variadic functions like goprintf cannot be described in the new
type information world, so we have to replace it.
Replace with a custom function, so that defer print(1, 2, 3) turns
into
defer func(a1, a2, a3 int) {
print(a1, a2, a3)
}(1, 2, 3)
(and then the print becomes three different printints as usual).
Fixes#8614.
LGTM=austin
R=austin
CC=golang-codereviews, r
https://golang.org/cl/159700043
I removed support for jumping between functions years ago,
as part of doing the instruction layout for each function separately.
Given that, it makes sense to treat labels as function-scoped.
This lets each function have its own 'loop' label, for example.
Makes the assembly much cleaner and removes the last
reason anyone would reach for the 123(PC) form instead.
Note that this is on the dev.power64 branch, but it changes all
the assemblers. The change will ship in Go 1.5 (perhaps after
being ported into the new assembler).
Came up as part of CL 167730043.
LGTM=r
R=r
CC=austin, dave, golang-codereviews, minux
https://golang.org/cl/159670043
The "to" field was the penultimate argument to outgcode,
instead of the last argument, which swapped the third and
fourth operands. The argument order was correct in a.y, so
just swap the meaning of the arguments in outgcode. This
hadn't come up because we hadn't used these more obscure
operations in any hand-written assembly until now.
LGTM=rsc, dave
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/160690043
get -u now checks that remote repo paths match the
ones predicted by the import paths: if you are get -u'ing
rsc.io/pdf, it has to be checked out from the right location.
This is important in case the rsc.io/pdf redirect changes.
In some cases, people have good reasons to use
non-standard remote repos. Add -f flag to allow that.
The f can stand for force or fork, as you see fit.
Fixes#8850.
LGTM=r
R=r
CC=golang-codereviews
https://golang.org/cl/164120043
This brings dev.power64 up-to-date with the current tip of
default. go_bootstrap is still panicking with a bad defer
when initializing the runtime (even on amd64).
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/152570049
This also removes pkg/runtime/traceback_lr.c, which was ported
to Go in an earlier commit and then moved to
runtime/traceback.go.
Reviewer: rsc@golang.org
rsc: LGTM
Partial undo, changes to ldelf.c retained.
Some platforms are still not working even with the integrated assembler disabled, will have to find another solution.
««« original CL description
cmd/cgo: disable clang's integrated assembler
Fixes#8348.
Clang's internal assembler (introduced by default in clang 3.4) understands the .arch directive, but doesn't change the default value of -march. This causes the build to fail when we use BLX (armv5 and above) when clang is compiled for the default armv4t architecture (which appears to be the default on all the distros I've used).
This is probably a clang bug, so work around it for the time being by disabling the integrated assembler when compiling the cgo assembly shim.
This CL also includes a small change to ldelf.c which was required as clang 3.4 and above generate more weird symtab entries.
LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/156430044
»»»
LGTM=minux
R=iant, minux
CC=golang-codereviews
https://golang.org/cl/162880044
This brings cmd/gc in line with the spec on this question.
It might break existing code, but that code was not conformant
with the spec.
Credit to Rémy for finding the broken code.
Fixes#6366.
LGTM=r
R=golang-codereviews, r
CC=adonovan, golang-codereviews, gri
https://golang.org/cl/129550043
Fixes#8348.
Clang's internal assembler (introduced by default in clang 3.4) understands the .arch directive, but doesn't change the default value of -march. This causes the build to fail when we use BLX (armv5 and above) when clang is compiled for the default armv4t architecture (which appears to be the default on all the distros I've used).
This is probably a clang bug, so work around it for the time being by disabling the integrated assembler when compiling the cgo assembly shim.
This CL also includes a small change to ldelf.c which was required as clang 3.4 and above generate more weird symtab entries.
LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/156430044
https://golang.org/cl/152700045/ made it possible for struct literals assigned to globals to use <N> as the RHS. Normally, this is to zero out variables on first use. Because globals are already zero (or their linker initialized value), we just ignored this.
Now that <N> can occur from non-initialization code, we need to emit this code. We don't use <N> for initialization of globals any more, so this shouldn't cause any excessive zeroing.
Fixes#8961.
LGTM=rsc
R=golang-codereviews, rsc
CC=bradfitz, golang-codereviews
https://golang.org/cl/154540044
Better to avoid the memory loads and just use immediate constants.
This especially applies to zeroing, which was being done by
copying zeros from elsewhere in the binary, even if the value
was going to be completely initialized with non-zero values.
The zero writes were optimized away but the zero loads from
the data segment were not.
LGTM=r
R=r, bradfitz, dvyukov
CC=golang-codereviews
https://golang.org/cl/152700045
hg was unable to create a CL on the code review server for this,
so I am submitting the merge by hand.
The only manual edits are in mgc0.c, to reapply the
removal of cached/ncached to the new code.
Both of these forms can avoid writing to the base pointer in x
(in the slice, always, and in the append, most of the time).
For Go 1.5, will need to change the compilation of x = x[0:y]
to avoid writing to the base pointer, so that the elision is safe,
and will need to change the compilation of x = append(x, ...)
to write to the base pointer (through a barrier) only when
growing the underlying array, so that the general elision is safe.
For Go 1.4, elide the write barrier always, a change that should
have equivalent performance characteristics but is much
simpler and therefore safer.
benchmark old ns/op new ns/op delta
BenchmarkBinaryTree17 3910526122 3918802545 +0.21%
BenchmarkFannkuch11 3747650699 3732600693 -0.40%
BenchmarkFmtFprintfEmpty 106 98.7 -6.89%
BenchmarkFmtFprintfString 280 269 -3.93%
BenchmarkFmtFprintfInt 296 282 -4.73%
BenchmarkFmtFprintfIntInt 467 470 +0.64%
BenchmarkFmtFprintfPrefixedInt 418 398 -4.78%
BenchmarkFmtFprintfFloat 574 535 -6.79%
BenchmarkFmtManyArgs 1768 1818 +2.83%
BenchmarkGobDecode 14916799 14925182 +0.06%
BenchmarkGobEncode 14110076 13358298 -5.33%
BenchmarkGzip 546609795 542630402 -0.73%
BenchmarkGunzip 136270657 136496277 +0.17%
BenchmarkHTTPClientServer 126574 125245 -1.05%
BenchmarkJSONEncode 30006238 27862354 -7.14%
BenchmarkJSONDecode 106020889 102664600 -3.17%
BenchmarkMandelbrot200 5793550 5818320 +0.43%
BenchmarkGoParse 5437608 5463962 +0.48%
BenchmarkRegexpMatchEasy0_32 192 179 -6.77%
BenchmarkRegexpMatchEasy0_1K 462 460 -0.43%
BenchmarkRegexpMatchEasy1_32 168 153 -8.93%
BenchmarkRegexpMatchEasy1_1K 1420 1280 -9.86%
BenchmarkRegexpMatchMedium_32 338 286 -15.38%
BenchmarkRegexpMatchMedium_1K 107435 98027 -8.76%
BenchmarkRegexpMatchHard_32 5941 4846 -18.43%
BenchmarkRegexpMatchHard_1K 185965 153830 -17.28%
BenchmarkRevcomp 795497458 798447829 +0.37%
BenchmarkTemplate 132091559 134938425 +2.16%
BenchmarkTimeParse 604 608 +0.66%
BenchmarkTimeFormat 551 548 -0.54%
LGTM=r
R=r, dave
CC=golang-codereviews, iant, khr, rlh
https://golang.org/cl/159960043
Among other things, *x = T{} does not need a write barrier.
The changes here avoid an unnecessary copy even when
no pointers are involved, so it may have larger effects.
In 6g and 8g, avoid manually repeated STOSQ in favor of
writing explicit MOVs, under the theory that the MOVs
should have fewer dependencies and pipeline better.
Benchmarks compare best of 5 on a 2012 MacBook Pro Core i5
with TurboBoost disabled. Most improvements can be explained
by the changes in this CL.
The effect in Revcomp is real but harder to explain: none of
the instructions in the inner loop changed. I suspect loop
alignment but really have no idea.
benchmark old new delta
BenchmarkBinaryTree17 3809027371 3819907076 +0.29%
BenchmarkFannkuch11 3607547556 3686983012 +2.20%
BenchmarkFmtFprintfEmpty 118 103 -12.71%
BenchmarkFmtFprintfString 289 277 -4.15%
BenchmarkFmtFprintfInt 304 290 -4.61%
BenchmarkFmtFprintfIntInt 507 458 -9.66%
BenchmarkFmtFprintfPrefixedInt 425 408 -4.00%
BenchmarkFmtFprintfFloat 555 555 +0.00%
BenchmarkFmtManyArgs 1835 1733 -5.56%
BenchmarkGobDecode 14738209 14639331 -0.67%
BenchmarkGobEncode 14239039 13703571 -3.76%
BenchmarkGzip 538211054 538701315 +0.09%
BenchmarkGunzip 135430877 134818459 -0.45%
BenchmarkHTTPClientServer 116488 116618 +0.11%
BenchmarkJSONEncode 28923406 29294334 +1.28%
BenchmarkJSONDecode 105779820 104289543 -1.41%
BenchmarkMandelbrot200 5791758 5771964 -0.34%
BenchmarkGoParse 5376642 5310943 -1.22%
BenchmarkRegexpMatchEasy0_32 195 190 -2.56%
BenchmarkRegexpMatchEasy0_1K 477 455 -4.61%
BenchmarkRegexpMatchEasy1_32 170 165 -2.94%
BenchmarkRegexpMatchEasy1_1K 1410 1394 -1.13%
BenchmarkRegexpMatchMedium_32 336 329 -2.08%
BenchmarkRegexpMatchMedium_1K 108979 106328 -2.43%
BenchmarkRegexpMatchHard_32 5854 5821 -0.56%
BenchmarkRegexpMatchHard_1K 185089 182838 -1.22%
BenchmarkRevcomp 834920364 780202624 -6.55%
BenchmarkTemplate 137046937 129728756 -5.34%
BenchmarkTimeParse 600 594 -1.00%
BenchmarkTimeFormat 559 539 -3.58%
LGTM=r
R=r
CC=golang-codereviews, iant, khr, rlh
https://golang.org/cl/157910047
The assembler could give a better error, but this one
is good enough for now.
Fixes#8880.
LGTM=r
R=r
CC=golang-codereviews
https://golang.org/cl/153610043
The racewalk code was not updated for the new write barriers.
Make it more future-proof.
The new write barrier code assumed that +1 pointer would
be aligned properly for any type that might follow, but that's
not true on 32-bit systems where some types are 64-bit aligned.
The only system like that today is nacl/amd64p32.
Insert a dummy pointer so that the ambiguously typed
value is at +2 pointers, which is always max-aligned.
LGTM=r
R=r
CC=golang-codereviews, iant, khr
https://golang.org/cl/158890046
Assignments of 2-, 3-, and 4-word values were handled
by individual MOV instructions (and for scalars still are).
But if there are pointers involved, those assignments now
go through the write barrier routine. Before this CL, they
went to writebarrierfat, which calls memmove.
Memmove is too much overhead for these small
amounts of data.
Instead, call writebarrierfat{2,3,4}, which are specialized
for the specific amount of data being copied.
Today the write barrier does not care which words are
pointers, so size alone is enough to distinguish the cases.
If we keep these distinctions in Go 1.5 we will need to
expand them for all the pointer-vs-scalar possibilities,
so the current 3 functions will become 3+7+15 = 25,
still not a large burden (we deleted more morestack
functions than that when we dropped segmented stacks).
BenchmarkBinaryTree17 3250972583 3123910344 -3.91%
BenchmarkFannkuch11 3067605223 2964737839 -3.35%
BenchmarkFmtFprintfEmpty 101 96.0 -4.95%
BenchmarkFmtFprintfString 267 235 -11.99%
BenchmarkFmtFprintfInt 261 253 -3.07%
BenchmarkFmtFprintfIntInt 444 402 -9.46%
BenchmarkFmtFprintfPrefixedInt 374 346 -7.49%
BenchmarkFmtFprintfFloat 472 449 -4.87%
BenchmarkFmtManyArgs 1537 1476 -3.97%
BenchmarkGobDecode 13986528 12432985 -11.11%
BenchmarkGobEncode 13120323 12537420 -4.44%
BenchmarkGzip 451925758 437500578 -3.19%
BenchmarkGunzip 113267612 110053644 -2.84%
BenchmarkHTTPClientServer 103151 77100 -25.26%
BenchmarkJSONEncode 25002733 23435278 -6.27%
BenchmarkJSONDecode 94213717 82568789 -12.36%
BenchmarkMandelbrot200 4804246 4713070 -1.90%
BenchmarkGoParse 4646114 4379456 -5.74%
BenchmarkRegexpMatchEasy0_32 163 158 -3.07%
BenchmarkRegexpMatchEasy0_1K 433 391 -9.70%
BenchmarkRegexpMatchEasy1_32 154 138 -10.39%
BenchmarkRegexpMatchEasy1_1K 1481 1132 -23.57%
BenchmarkRegexpMatchMedium_32 282 270 -4.26%
BenchmarkRegexpMatchMedium_1K 92421 86149 -6.79%
BenchmarkRegexpMatchHard_32 5209 4718 -9.43%
BenchmarkRegexpMatchHard_1K 158141 147921 -6.46%
BenchmarkRevcomp 699818791 642222464 -8.23%
BenchmarkTemplate 132402383 108269713 -18.23%
BenchmarkTimeParse 509 478 -6.09%
BenchmarkTimeFormat 462 456 -1.30%
LGTM=r
R=r
CC=golang-codereviews
https://golang.org/cl/156200043
Our current pe object reader assumes that every symbol starting with
'.' is section. It appeared to be true, until now gcc 4.9.1 generates
some symbols with '.' at the front. Change that logic to check other
symbol fields in addition to checking for '.'. I am not an expert
here, but it seems reasonable to me.
Added test, but it is only good, if tested with gcc 4.9.1. Otherwise
the test PASSes regardless.
Fixes#8811.
Fixes#8856.
LGTM=jfrederich, iant, stephen.gutekanst
R=golang-codereviews, jfrederich, stephen.gutekanst, iant
CC=alex.brainman, golang-codereviews
https://golang.org/cl/152410043
gcc 4.9.1 generates pe sections with names longer then 8 charters.
From IMAGE_SECTION_HEADER definition:
Name
An 8-byte, null-padded UTF-8 string. There is no terminating null character
if the string is exactly eight characters long. For longer names, this
member contains a forward slash (/) followed by an ASCII representation
of a decimal number that is an offset into the string table.
Our current pe object file reader does not read string table when section
names starts with /. Do that, so (issue 8811 example)
c:\go\path\src\isssue8811>go build
# isssue8811
isssue8811/glfw(.text): isssue8811/glfw(/76): not defined
isssue8811/glfw(.text): undefined: isssue8811/glfw(/76)
becomes
c:\go\path\src\isssue8811>go build
# isssue8811
isssue8811/glfw(.text): isssue8811/glfw(.rdata$.refptr._glfwInitialized): not defined
isssue8811/glfw(.text): undefined: isssue8811/glfw(.rdata$.refptr._glfwInitialized)
Small progress to
Update #8811
LGTM=iant, jfrederich
R=golang-codereviews, iant, jfrederich
CC=golang-codereviews
https://golang.org/cl/154210044
I diffed the output of `nm -n gofmt' before and after this change,
and verified that all changes are correct and all corrupted symbol
names are fixed.
Fixes#8906.
LGTM=iant, cookieo9
R=golang-codereviews, iant, cookieo9
CC=golang-codereviews
https://golang.org/cl/159750043
It seems reasonable that people might want to look up the
ImportComment with "go list".
LGTM=r
R=golang-codereviews, r
CC=golang-codereviews
https://golang.org/cl/143600043
This will help find bugs during the release freeze.
It's not clear it should be kept for the release itself.
That's issue 8861.
The most likely thing that would trigger this is stale
pointers that previously were ignored or caused memory
leaks. These were allowed due to the use of conservative
collection. Now that everything is precise, we should not
see them anymore.
The small number check reinforces what the stack copier
is already doing, catching the storage of integers in pointers.
It caught issue 8864.
The check is disabled if _cgo_allocate is linked into the binary,
which is to say if the binary is using SWIG to allocate untyped
Go memory. In that case, there are invalid pointers and there's
nothing we can do about it.
LGTM=rlh
R=golang-codereviews, dvyukov, rlh
CC=golang-codereviews, iant, khr, r
https://golang.org/cl/148470043