A new environment variable GO386 is introduced to choose between
code generation targeting 387 or SSE2. No auto-detection is
performed and the setting defaults to 387 to preserve previous
behaviour.
The patch is a reorganization of CL6549052 by rsc.
Fixes#3912.
R=minux.ma, rsc
CC=golang-dev
https://golang.org/cl/6962043
Unnamed types like structs with embedded fields can have methods.
These methods are generated on-the-fly by the compiler and
it may happen for identical types in different packages.
The linker must accept these multiple definitions.
Fixes#4590.
R=golang-dev, rsc
CC=golang-dev, remy
https://golang.org/cl/7030051
Before this CL, defining the variable worked fine, but then when
the implicit package-level init func was created, that caused a
name collision and a confusing error about the redeclaration.
Also add a test for issue 3705 (func init() needs body).
Fixes#4517.
R=ken2
CC=golang-dev
https://golang.org/cl/7008045
An error during the compilation can be more precise
than an error at link time.
For 'func init', the error happens always: you can't forward
declare an init func because the name gets mangled.
For other funcs, the error happens only with the special
(and never used by hand) -= flag, which tells 6g the
package is pure go.
The go command now passes -= for pure Go packages.
Fixes#3705.
R=ken2
CC=golang-dev
https://golang.org/cl/6996054
Ordinary variable load was assumed to be not worth saving,
but not if one of the function calls later might change
its value.
Fixes#4313.
R=ken2
CC=golang-dev
https://golang.org/cl/6997047
The patch makes the compile user an ordinary package-local
symbol for the name of embedded fields of builtin type.
This is incompatible with the fix delivered for issue 2687
(revision 3c060add43fb) but fixes it in a different way, because
the explicit symbol on the field makes the typechecker able to
find it in lookdot.
Fixes#3552.
R=lvd, rsc, daniel.morsing
CC=golang-dev
https://golang.org/cl/6866047
The typechecking code was doing an extra, unnecessary
indirection.
Fixes#4458.
R=golang-dev, daniel.morsing, rsc
CC=golang-dev
https://golang.org/cl/6998051
remove zerostack compiler experiment; will do at link time instead
««« original CL description
cmd/gc: add GOEXPERIMENT=zerostack to clear stack on function entry
This is expensive but it might be useful in cases where
people are suffering from false positives during garbage
collection and are willing to trade the CPU time for getting
rid of the false positives.
On the other hand it only eliminates false positives caused
by other function calls, not false positives caused by dead
temporaries stored in the current function call.
The 5g/6g/8g changes were pulled out of the history, from
the last time we needed to do this (to work around a goto bug).
The code in go.h, lex.c, pgen.c is new but tiny.
R=ken2
CC=golang-dev
https://golang.org/cl/6938073
»»»
R=ken2
CC=golang-dev
https://golang.org/cl/7002051
A fatal error used to happen when escassign-ing a multiple
function return to a single node. However, the situation
naturally appears when using "go f(g())" or "defer f(g())",
because g() is escassign-ed to sink.
Fixes#4529.
R=golang-dev, lvd, minux.ma, rsc
CC=golang-dev
https://golang.org/cl/6920060
The OpenBSD ld.so(1) does not currently support PT_TLS and refuses
to load ELF binaries that contain PT_TLS sections. Do not emit PT_TLS
sections - we will handle this appropriately in runtime/cgo instead.
R=golang-dev, minux.ma, iant
CC=golang-dev
https://golang.org/cl/6846064
This is expensive but it might be useful in cases where
people are suffering from false positives during garbage
collection and are willing to trade the CPU time for getting
rid of the false positives.
On the other hand it only eliminates false positives caused
by other function calls, not false positives caused by dead
temporaries stored in the current function call.
The 5g/6g/8g changes were pulled out of the history, from
the last time we needed to do this (to work around a goto bug).
The code in go.h, lex.c, pgen.c is new but tiny.
R=ken2
CC=golang-dev
https://golang.org/cl/6938073
The code:
func main() {
v := make([]int64, 10)
i := 1
_ = v[(i*4)/3]
}
crashes compiler with:
Program received signal SIGSEGV, Segmentation fault.
0x000000000043c274 in walkexpr (np=0x7fffffffc9b8, init=0x0) at src/cmd/gc/walk.c:587
587 *init = concat(*init, n->ninit);
(gdb) bt
#0 0x000000000043c274 in walkexpr (np=0x7fffffffc9b8, init=0x0) at src/cmd/gc/walk.c:587
#1 0x0000000000432d15 in copyexpr (n=0x7ffff7f69a48, t=<optimized out>, init=0x0) at src/cmd/gc/subr.c:2020
#2 0x000000000043f281 in walkdiv (init=0x0, np=0x7fffffffca70) at src/cmd/gc/walk.c:2901
#3 walkexpr (np=0x7ffff7f69760, init=0x0) at src/cmd/gc/walk.c:956
#4 0x000000000043d801 in walkexpr (np=0x7ffff7f69bc0, init=0x0) at src/cmd/gc/walk.c:988
#5 0x000000000043cc9b in walkexpr (np=0x7ffff7f69d38, init=0x0) at src/cmd/gc/walk.c:1068
#6 0x000000000043c50b in walkexpr (np=0x7ffff7f69f50, init=0x0) at src/cmd/gc/walk.c:879
#7 0x000000000043c50b in walkexpr (np=0x7ffff7f6a0c8, init=0x0) at src/cmd/gc/walk.c:879
#8 0x0000000000440a53 in walkexprlist (l=0x7ffff7f6a0c8, init=0x0) at src/cmd/gc/walk.c:357
#9 0x000000000043d0bf in walkexpr (np=0x7fffffffd318, init=0x0) at src/cmd/gc/walk.c:566
#10 0x00000000004402bf in vmkcall (fn=<optimized out>, t=0x0, init=0x0, va=0x7fffffffd368) at src/cmd/gc/walk.c:2275
#11 0x000000000044059a in mkcall (name=<optimized out>, t=0x0, init=0x0) at src/cmd/gc/walk.c:2287
#12 0x000000000042862b in callinstr (np=0x7fffffffd4c8, init=0x7fffffffd568, wr=0, skip=<optimized out>) at src/cmd/gc/racewalk.c:478
#13 0x00000000004288b7 in racewalknode (np=0x7ffff7f68108, init=0x7fffffffd568, wr=0, skip=0) at src/cmd/gc/racewalk.c:287
#14 0x0000000000428781 in racewalknode (np=0x7ffff7f65840, init=0x7fffffffd568, wr=0, skip=0) at src/cmd/gc/racewalk.c:302
#15 0x0000000000428abd in racewalklist (l=0x7ffff7f65840, init=0x0) at src/cmd/gc/racewalk.c:97
#16 0x0000000000428d0b in racewalk (fn=0x7ffff7f5f010) at src/cmd/gc/racewalk.c:63
#17 0x0000000000402b9c in compile (fn=0x7ffff7f5f010) at src/cmd/6g/../gc/pgen.c:67
#18 0x0000000000419f86 in funccompile (n=0x7ffff7f5f010, isclosure=0) at src/cmd/gc/dcl.c:1414
#19 0x0000000000424161 in p9main (argc=<optimized out>, argv=<optimized out>) at src/cmd/gc/lex.c:431
#20 0x0000000000401739 in main (argc=<optimized out>, argv=<optimized out>) at src/lib9/main.c:35
The problem is nil init passed to mkcall().
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/6940045
Ignore signals during "go run" and wait for running child
process to exit. Stop executing further tests during "go test",
wait for running tests to exit and report error exit code.
Original CL 6351053 by dfc.
Fixes#3572.
Fixes#3581.
R=golang-dev, dave, rsc
CC=golang-dev
https://golang.org/cl/6903061
5g: Prog went from 128 bytes to 88 bytes
6g: Prog went from 174 bytes to 144 bytes
8g: Prog went from 124 bytes to 92 bytes
There may be a little more that can be squeezed out of Addr, but alignment will be a factor.
All: remove the unused pun field from Addr
R=rsc, minux.ma
CC=golang-dev
https://golang.org/cl/6922048
Change suggested by iant. The compiler generates
special code for a/b when a is -0x80...0 and b = -1.
A single instruction can cover the case where b is -1,
so only one comparison is needed.
Fixes#3551.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/6922049
The code inside the casee and casep labels can perfectly be merged since
they essentially do the same. The character to be stored where cp points is
just the character contained by the c variable.
R=golang-dev, dave, rsc
CC=golang-dev
https://golang.org/cl/6845112
This check for BADWIDTH might happen while in defercheckwidth, making it raise errors for non-erroneous situations.
Fixes#4495.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/6927043
Fixes#4492.
% go version
go version devel +6b602ab487d6 Sat Dec 08 14:43:00 2012 +0100 linux/amd64
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/6906058
The fixjmp step eliminates redundant chains of JMP
instructions that are produced by the compiler during
code generation.
It is already implemented in gc, and can be adapted to 6c/8c with
the exception that JMPs refer to destination by pc instead of by
pointer. The algorithm is modified to operate on Regs instead of Progs
for this reason. The pcs are already restored later by regopt.
R=goalng-dev, rsc
CC=golang-dev
https://golang.org/cl/6865046
Add missing file that should have been included in CL 6854063 / 5eac1a2d6fc3
R=remyoudompheng, minux.ma, rsc
CC=golang-dev
https://golang.org/cl/6891049
The 0-length part is fine, but some callers that write 0 bytes
also pass nil as the data pointer, and the Plan 9 kernel kills the
process with 'invalid address in sys call' in that case.
R=ken2
CC=golang-dev
https://golang.org/cl/6862051
Used to say:
issue4251.go:12: inverted slice range
issue4251.go:12: constant -1 overflows uint64
issue4251.go:16: inverted slice range
issue4251.go:16: constant -1 overflows uint64
issue4251.go:20: inverted slice range
issue4251.go:20: constant -1 overflows uint64
With this patch, only gives the "inverted slice range" errors.
R=golang-dev, daniel.morsing
CC=golang-dev
https://golang.org/cl/6871058
Fixes#4396.
For fixed arrays larger than the unmapped page, agenr would general a nil check by loading the first word of the array. However there is no requirement for the first element of a byte array to be word aligned, so this check causes a trap on ARMv5 hardware (ARMv6 since relaxed that restriction, but it probably still comes at a cost).
Switching the check to MOVB ensures alignment is not an issue. This check is only invoked in a few places in the code where large fixed arrays are embedded into structs, compress/lzw is the biggest offender, and switching to MOVB has no observable performance penalty.
Thanks to Rémy and Daniel Morsing for helping me debug this on IRC last night.
R=remyoudompheng, minux.ma, rsc
CC=golang-dev
https://golang.org/cl/6854063
The debian/kFreeBSD project uses the FreeBSD kernel and the debian userspace. From our point of view, this is freebsd not linux as GOOS talks about the kernel syscall interface, not the userspace (although cgo alters that). As debian/kFreeBSD is experimental at this time, I do not think it is worth the effort of duplicating all the freebsd specific code so this is proposal represents a reasonable workaround.
Currently cgo is not supported, make.bash will detect this and disable cgo automatically during the build.
dfc@debian:~/go/src$ uname -a
GNU/kFreeBSD debian 8.1-1-686 #0 Sat Jul 21 17:02:04 UTC 2012 i686 i386 Intel(R) Core(TM) i5-2415M CPU @ 2.30GHz GNU/kFreeBSD
dfc@debian:~/go/src$ ../bin/go version
go version devel +d05272f402ec Sat Dec 01 15:15:14 2012 -0800
Tested with GOOS=freebsd GOARCH=386
R=golang-dev
CC=golang-dev
https://golang.org/cl/6868046
The compiler was confused when inlining a T.Method(f()) call
where f returns multiple values: support for this was marked
as TODO.
Variadic calls are not supported but are not inlined either.
Add a test preventively for that case.
Fixes#4167.
R=golang-dev, rsc, lvd
CC=golang-dev
https://golang.org/cl/6871043
`godoc net/http` used to complain "/target contains more than one package: http, main"
R=golang-dev, bradfitz, rsc
CC=golang-dev
https://golang.org/cl/6852100
W/o this change stack traces do not show from where sync.Once()
or atomic.XXX was called.
This change add funcenter/exit instrumentation to sync/sync.atomic
packages.
R=golang-dev
CC=golang-dev
https://golang.org/cl/6854112
Package format is a utility package that takes care of
parsing, sorting of imports, and formatting of .go source
using the canonical gofmt formatting parameters.
Use go/format in various clients instead of the lower-level components.
R=r, bradfitz, dave, rogpeppe, rsc
CC=golang-dev
https://golang.org/cl/6852075
This allows 5g and 8g to benefit from the rewrite as shifts
or magic multiplies. The 64-bit arithmetic is not handled there,
and left in 6g.
Update #2230.
R=golang-dev, dave, mtj, iant, rsc
CC=golang-dev
https://golang.org/cl/6819123
Bools from comparisons can be assigned to all bool types, but this idealness would propagate through logical operators when the result should have been lowered to a non-ideal form.
Fixes#3924.
R=golang-dev, remyoudompheng, r, rsc, mtj
CC=golang-dev
https://golang.org/cl/6855061
The stack overflow checker in the linker uses the spadj field
to determine whether stack space will be large enough or not.
When spadj=0, the checker treats the function as a nosplit
and emits an error although the program is correct.
Also enable the stack checker in 8l.
Fixes#4316.
R=rsc, golang-dev
CC=golang-dev
https://golang.org/cl/6855088
The 8l linker automatically inserts XCHG instructions
to support otherwise impossible byte registers
(only available on AX, BX, CX, DX).
Sometimes AX or DX is needed (for MUL and DIV) so
we need to avoid clobbering them.
R=golang-dev, dave, iant, iant, rsc
CC=golang-dev
https://golang.org/cl/6846057
This CL starts to introduce IPv6 scoped addressing capability
into the net package.
The Public API changes are:
+pkg net, type IPAddr struct, Zone string
+pkg net, type IPNet struct, Zone string
+pkg net, type TCPAddr struct, Zone string
+pkg net, type UDPAddr struct, Zone string
Update #4234.
R=rsc, bradfitz, iant
CC=golang-dev
https://golang.org/cl/6849045
Check the return value from malloc - do not assume that we were
allocated memory just because we asked for it.
Update #4415.
R=minux.ma, daniel.morsing, remyoudompheng, rsc
CC=golang-dev
https://golang.org/cl/6782100
Saves 5 seconds on my machine. If Issue 4380 is fixed this
clone can be removed.
Update #4380
R=golang-dev, remyoudompheng, minux.ma, gri
CC=golang-dev
https://golang.org/cl/6845058
In order to add these, we need to be able to find references
to such types that already exist in the binary. To do that, introduce
a new linker section holding a list of the types corresponding to
arrays, chans, maps, and slices.
To offset the storage cost of this list, and to simplify the code,
remove the interface{} header from the representation of a
runtime type. It was used in early versions of the code but was
made obsolete by the kind field: a switch on kind is more efficient
than a type switch.
In the godoc binary, removing the interface{} header cuts two
words from each of about 10,000 types. Adding back the list of pointers
to array, chan, map, and slice types reintroduces one word for
each of about 500 types. On a 64-bit machine, then, this CL *removes*
a net 156 kB of read-only data from the binary.
This CL does not include the needed support for precise garbage
collection. I have created issue 4375 to track that.
This CL also does not set the 'algorithm' - specifically the equality
and copy functions - for a new array correctly, so I have unexported
ArrayOf for now. That is also part of issue 4375.
Fixes#2339.
R=r, remyoudompheng, mirtchovski, iant
CC=golang-dev
https://golang.org/cl/6572043
This patch introduces a sort of pre-regopt peephole optimization.
When a temporary is introduced that just holds a value for the
duration of the next instruction and is otherwise unused, we
elide it to make the job of regopt easier.
Since x86 has very few registers, this situation happens very
often. The result is large savings in stack variables for
arithmetic-heavy functions.
crypto/aes
benchmark old ns/op new ns/op delta
BenchmarkEncrypt 1301 392 -69.87%
BenchmarkDecrypt 1309 368 -71.89%
BenchmarkExpand 2913 1036 -64.44%
benchmark old MB/s new MB/s speedup
BenchmarkEncrypt 12.29 40.74 3.31x
BenchmarkDecrypt 12.21 43.37 3.55x
crypto/md5
benchmark old ns/op new ns/op delta
BenchmarkHash8Bytes 1761 914 -48.10%
BenchmarkHash1K 16912 5570 -67.06%
BenchmarkHash8K 123895 38286 -69.10%
benchmark old MB/s new MB/s speedup
BenchmarkHash8Bytes 4.54 8.75 1.93x
BenchmarkHash1K 60.55 183.83 3.04x
BenchmarkHash8K 66.12 213.97 3.24x
bench/go1
benchmark old ns/op new ns/op delta
BenchmarkBinaryTree17 8364835000 8303154000 -0.74%
BenchmarkFannkuch11 7511723000 6381729000 -15.04%
BenchmarkGobDecode 27764090 27103270 -2.38%
BenchmarkGobEncode 11240880 11184370 -0.50%
BenchmarkGzip 1470224000 856668400 -41.73%
BenchmarkGunzip 240660800 201697300 -16.19%
BenchmarkJSONEncode 155225800 185571900 +19.55%
BenchmarkJSONDecode 243347900 282123000 +15.93%
BenchmarkMandelbrot200 12240970 12201880 -0.32%
BenchmarkParse 8837445 8765210 -0.82%
BenchmarkRevcomp 2556310000 1868566000 -26.90%
BenchmarkTemplate 389298000 379792000 -2.44%
benchmark old MB/s new MB/s speedup
BenchmarkGobDecode 27.64 28.32 1.02x
BenchmarkGobEncode 68.28 68.63 1.01x
BenchmarkGzip 13.20 22.65 1.72x
BenchmarkGunzip 80.63 96.21 1.19x
BenchmarkJSONEncode 12.50 10.46 0.84x
BenchmarkJSONDecode 7.97 6.88 0.86x
BenchmarkParse 6.55 6.61 1.01x
BenchmarkRevcomp 99.43 136.02 1.37x
BenchmarkTemplate 4.98 5.11 1.03x
Fixes#4035.
R=golang-dev, minux.ma, rsc
CC=golang-dev
https://golang.org/cl/6828056
The patch adds more cases to agenr to allocate registers later,
and makes 6g generate addresses for sgen in something else than
SI and DI. It avoids a complex save/restore sequence that
amounts to allocate a register before descending in subtrees.
Fixes#4207.
R=golang-dev, dave, rsc
CC=golang-dev
https://golang.org/cl/6817080
xtramodes' C_PBIT optimisation transforms:
MOVW 0(R3),R1
ADD $4,R3,R3
into:
MOVW.P 4(R3),R1
and the AADD optimisation tranforms:
ADD R0,R1
MOVBU 0(R1),R0
into:
MOVBU R0<<0(R1),R0
5g does not appear to generate sequences that
can be transformed by xtramodes' AMOVW.
R=remyoudompheng, rsc
CC=golang-dev
https://golang.org/cl/6817085
On ARM, char is unsigned, and the code generation for
multiplication gets totally broken.
Fixes#4354.
R=golang-dev, dave, minux.ma, rsc
CC=golang-dev
https://golang.org/cl/6826079
Currently it works incorrectly if user specifies own build tags
and with race detection (e.g. runtime/race is not selected,
because it contains only test files with +build race).
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/6814107