The layout code has to date insisted on stack frames that are 16-aligned
including the saved LR, and it ensured this by growing the frame itself.
This breaks code that refers to values near the top of the frame by positive
offset from SP, and in general it's too magical: if you see TEXT xxx, $N,
you expect that the frame size is actually N, not sometimes N and sometimes N+8.
This led to a serious bug in the compiler where ambiguously live values
were not being zeroed correctly, which in turn triggered an assertion
in the GC about finding only valid pointers. The compiler has been
fixed to always emit aligned frames, and the hand-written assembly
has also been fixed.
Now that everything is aligned, make unaligned an error instead of
something to "fix" silently.
For #9880.
Change-Id: I05f01a9df174d64b37fa19b36a6b6c5f18d5ba2d
Reviewed-on: https://go-review.googlesource.com/12848
Reviewed-by: Austin Clements <austin@google.com>
This is dead code that was missed
during the 'go tool compile' migration.
Change-Id: Ice2af8a9ef72f8fd5f82225ee261854d93b659f1
Reviewed-on: https://go-review.googlesource.com/10430
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This CL fixes the build to use the newly created go tool compile
and go tool link in place of go tool 5g, go tool 5l, and so on.
See golang-dev thread titled "go tool compile, etc" for background.
Although it was not a primary motivation, this conversion does
reduce the wall clock time and cpu time required for make.bash
by about 10%.
Change-Id: I79cbbdb676cab029db8aeefb99a53178ff55f98d
Reviewed-on: https://go-review.googlesource.com/10288
Reviewed-by: Rob Pike <r@golang.org>
Noopt builds get a larger stack guard. This test must take that into account.
Change-Id: I1b5cbafdbbfee8c369ae1bebd0b900524ebf0d7d
Reviewed-on: https://go-review.googlesource.com/9610
Reviewed-by: Russ Cox <rsc@golang.org>
The main issue is that the misc/cgo/{stdio,life} tests are silently
getting skipped when invoked from run.bash.
run.go should ignore any build tags after the first blank line in
source file. It already checks for test actions only upto the first
blank line. Build tags must be specified in the same block.
See http://golang.org/cl/3675 for background.
Change-Id: Id8abf000119e3335f7250d8ef34aac7811fc9dff
Reviewed-on: https://go-review.googlesource.com/3812
Reviewed-by: Minux Ma <minux@golang.org>
This adds a "framepointer" GOEXPERIMENT that that makes the amd64
toolchain maintain base pointer chains in the same way that gcc
-fno-omit-frame-pointer does. Go doesn't use these saved base
pointers, but this does enable external tools like Linux perf and
VTune to unwind Go stacks when collecting system-wide profiles.
This requires support in the compilers to not clobber BP, support in
liblink for generating the BP-saving function prologue and unwinding
epilogue, and support in the runtime to save BPs across preemption, to
skip saved BPs during stack unwinding and, and to adjust saved BPs
during stack moving.
As with other GOEXPERIMENTs, everything from the toolchain to the
runtime must be compiled with this experiment enabled. To do this,
run make.bash (or all.bash) with GOEXPERIMENT=framepointer.
Change-Id: I4024853beefb9539949e5ca381adfdd9cfada544
Reviewed-on: https://go-review.googlesource.com/2992
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
640 bytes ought to be enough for anybody.
We'll bring this back down before Go 1.5. That's issue 9214.
TBR=rlh
CC=golang-codereviews
https://golang.org/cl/188730043
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
If there is a leading ·, assume there is a Go prototype and
attach the Go prototype information to the function.
If the function is not called from Go and does not need a
Go prototype, it can be made file-local instead (using name<>(SB)).
This fixes the current BSD build failures, by giving functions like
sync/atomic.StoreUint32 argument stack map information.
Fixes#8753.
LGTM=khr, iant
R=golang-codereviews, iant, khr, bradfitz
CC=golang-codereviews, r, rlh
https://golang.org/cl/142150043
Increase NOSPLIT reservation from 192 to 384 bytes.
The problem is that the non-Unix systems (Solaris and Windows)
just can't make system calls in a small amount of space,
and then worse they do things that are complex enough
to warrant calling runtime.throw on failure.
We don't have time to rewrite the code to use less stack.
I'm not happy about this, but it's still a small amount.
The good news is that we're doing this to get to only
using copying stacks for stack growth. Once that is true,
we can drop the default stack size from 8k to 4k, which
should more than make up for the bytes we're losing here.
LGTM=r
R=iant, r, bradfitz, aram.h
CC=golang-codereviews
https://golang.org/cl/140350043
In CL 131450043, which raised it to 160,
I'd raise it to 192 if necessary.
Apparently it is necessary on windows/amd64.
One note for those concerned about the growth:
in the old segmented stack world, we wasted this much
space at the bottom of every stack segment.
In the new contiguous stack world, each goroutine has
only one stack segment, so we only waste this much space
once per goroutine. So even raising the limit further might
still be a net savings.
Fixes windows/amd64 build.
TBR=r
CC=golang-codereviews
https://golang.org/cl/132480043
The Go calling convention uses more stack space than C.
On 64-bit systems we've been right up against the limit
(128 bytes, so only 16 words) and doing awful things to
our source code to work around it. Instead of continuing
to do awful things, raise the limit to 160 bytes.
I am prepared to raise the limit to 192 bytes if necessary,
but I think this will be enough.
Should fix current link-time stack overflow errors on
- nacl/arm
- netbsd/amd64
- openbsd/amd64
- solaris/amd64
- windows/amd64
TBR=r
CC=golang-codereviews, iant
https://golang.org/cl/131450043
Add nacl.bash, the NaCl version of all.bash.
It's a separate script because it builds a variant of package syscall
with a large zip file embedded in it, containing all the input files
needed for tests.
Disable various tests new since the last round, mostly the ones using os/exec.
Fixes#7945.
LGTM=dave
R=golang-codereviews, remyoudompheng, dave, bradfitz
CC=golang-codereviews
https://golang.org/cl/100590044
The new code is adapted from the Go 1.2 nosplit code,
but it does not have the bug reported in issue 7623:
g% go run nosplit.go
g% go1.2 run nosplit.go
BUG
rejected incorrectly:
main 0 call f; f 120
linker output:
# _/tmp/go-test-nosplit021064539
main.main: nosplit stack overflow
120 guaranteed after split check in main.main
112 on entry to main.f
-8 after main.f uses 120
g%
Fixes#6931.
Fixes#7623.
LGTM=iant
R=golang-codereviews, iant, ality
CC=golang-codereviews, r
https://golang.org/cl/88190043
