mirror
/
go
mirror of https://github.com/golang/go.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

runtime: use unsigned load for iscgo variable in ppc64x runtime asm 

This changes the runtime asm code that loads iscgo to use MOVBZ
instead of MOVB, avoiding an unnecessary sign extension. This is most
significant in runtime.save_g, reducing the size from 8 to 7
instructions.

Change-Id: Iaa2121464b5309e1f27fd91b19b5603c7aaf619d
Reviewed-on: https://go-review.googlesource.com/c/144217
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
This commit is contained in:
Lynn Boger 2018-10-22 16:02:43 -04:00
parent 6994731ec2
commit e41fbc79cc
3 changed files with 3 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
src/runtime/asm_ppc64x.s
View File

@ -648,7 +648,7 @@ TEXT ·cgocallback_gofunc(SB),NOSPLIT,$16-32
NO_LOCAL_POINTERS
// Load m and g from thread-local storage.
MOVB runtime·iscgo(SB), R3
MOVBZ runtime·iscgo(SB), R3
CMP R3, $0
BEQ nocgo
BL runtime·load_g(SB)

2
src/runtime/sys_linux_ppc64x.s
View File

@ -301,7 +301,7 @@ TEXT runtime·_sigtramp(SB),NOSPLIT,$64
// this might be called in external code context,
// where g is not set.
MOVB runtime·iscgo(SB), R6
MOVBZ runtime·iscgo(SB), R6
CMP R6, $0
BEQ 2(PC)
BL runtime·load_g(SB)

2
src/runtime/tls_ppc64x.s
View File

@ -24,7 +24,7 @@
// NOTE: setg_gcc<> assume this clobbers only R31.
TEXT runtime·save_g(SB),NOSPLIT|NOFRAME,$0-0
#ifndef GOOS_aix
MOVB runtime·iscgo(SB), R31
MOVBZ runtime·iscgo(SB), R31
CMP R31, $0
BEQ nocgo
#endif