diff options
author | Russ Cox <rsc@golang.org> | 2014-09-04 00:01:55 -0400 |
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committer | Russ Cox <rsc@golang.org> | 2014-09-04 00:01:55 -0400 |
commit | 82105b28f41fe63cbe2eaecf687659be44266d04 (patch) | |
tree | 1d942471032ae6fb056ea2d5cb324bcd269fd484 /src/pkg | |
parent | d28eaeb139d3c1cc90b86e55d0f3343c0ffa16fb (diff) | |
download | go-82105b28f41fe63cbe2eaecf687659be44266d04.tar.gz |
runtime: refactor/fix asmcgocall/asmcgocall_errno
Instead of making asmcgocall call asmcgocall_errno,
make both load args into registers and call a shared
assembly function.
On amd64, this costs 1 word in the asmcgocall_errno path
but saves 3 words in the asmcgocall path, and the latter
is what happens on critical nosplit paths on Windows.
On arm, this fixes build failures: asmcgocall was writing
the arguments for asmcgocall_errno into the wrong
place on the stack. Passing them in registers avoids the
decision entirely.
On 386, this isn't really needed, since the nosplit paths
have twice as many words to work with, but do it for consistency.
Update issue 8635
Fixes arm build (except GOARM=5).
TBR=iant
CC=golang-codereviews
https://codereview.appspot.com/134390043
Diffstat (limited to 'src/pkg')
-rw-r--r-- | src/pkg/runtime/asm_386.s | 13 | ||||
-rw-r--r-- | src/pkg/runtime/asm_amd64.s | 13 | ||||
-rw-r--r-- | src/pkg/runtime/asm_arm.s | 15 |
3 files changed, 25 insertions, 16 deletions
diff --git a/src/pkg/runtime/asm_386.s b/src/pkg/runtime/asm_386.s index 2477726f5..aafe960ce 100644 --- a/src/pkg/runtime/asm_386.s +++ b/src/pkg/runtime/asm_386.s @@ -680,17 +680,21 @@ TEXT gosave<>(SB),NOSPLIT,$0 // Call fn(arg) on the scheduler stack, // aligned appropriately for the gcc ABI. // See cgocall.c for more details. -TEXT runtime·asmcgocall(SB),NOSPLIT,$12-8 +TEXT runtime·asmcgocall(SB),NOSPLIT,$0-8 MOVL fn+0(FP), AX MOVL arg+4(FP), BX - MOVL AX, 0(SP) - MOVL BX, 4(SP) - CALL runtime·asmcgocall_errno(SB) + CALL asmcgocall<>(SB) RET TEXT runtime·asmcgocall_errno(SB),NOSPLIT,$0-12 MOVL fn+0(FP), AX MOVL arg+4(FP), BX + CALL asmcgocall<>(SB) + MOVL AX, ret+8(FP) + RET + +TEXT asmcgocall<>(SB),NOSPLIT,$0-12 + // fn in AX, arg in BX MOVL SP, DX // Figure out if we need to switch to m->g0 stack. @@ -720,7 +724,6 @@ TEXT runtime·asmcgocall_errno(SB),NOSPLIT,$0-12 MOVL 8(SP), DI MOVL DI, g(CX) MOVL 4(SP), SP - MOVL AX, ret+8(FP) RET // cgocallback(void (*fn)(void*), void *frame, uintptr framesize) diff --git a/src/pkg/runtime/asm_amd64.s b/src/pkg/runtime/asm_amd64.s index d7e30de7b..5840b56c8 100644 --- a/src/pkg/runtime/asm_amd64.s +++ b/src/pkg/runtime/asm_amd64.s @@ -764,17 +764,21 @@ TEXT gosave<>(SB),NOSPLIT,$0 // Call fn(arg) on the scheduler stack, // aligned appropriately for the gcc ABI. // See cgocall.c for more details. -TEXT runtime·asmcgocall(SB),NOSPLIT,$24-16 +TEXT runtime·asmcgocall(SB),NOSPLIT,$0-16 MOVQ fn+0(FP), AX MOVQ arg+8(FP), BX - MOVQ AX, 0(SP) - MOVQ BX, 8(SP) - CALL runtime·asmcgocall_errno(SB) + CALL asmcgocall<>(SB) RET TEXT runtime·asmcgocall_errno(SB),NOSPLIT,$0-20 MOVQ fn+0(FP), AX MOVQ arg+8(FP), BX + CALL asmcgocall<>(SB) + MOVL AX, ret+16(FP) + RET + +// asmcgocall common code. fn in AX, arg in BX. returns errno in AX. +TEXT asmcgocall<>(SB),NOSPLIT,$0-0 MOVQ SP, DX // Figure out if we need to switch to m->g0 stack. @@ -813,7 +817,6 @@ nosave: MOVQ 48(SP), DI MOVQ DI, g(CX) MOVQ 40(SP), SP - MOVL AX, ret+16(FP) RET // cgocallback(void (*fn)(void*), void *frame, uintptr framesize) diff --git a/src/pkg/runtime/asm_arm.s b/src/pkg/runtime/asm_arm.s index 26b58cfb1..49a863258 100644 --- a/src/pkg/runtime/asm_arm.s +++ b/src/pkg/runtime/asm_arm.s @@ -493,17 +493,21 @@ TEXT gosave<>(SB),NOSPLIT,$0 // Call fn(arg) on the scheduler stack, // aligned appropriately for the gcc ABI. // See cgocall.c for more details. -TEXT runtime·asmcgocall(SB),NOSPLIT,$12-8 +TEXT runtime·asmcgocall(SB),NOSPLIT,$0-8 MOVW fn+0(FP), R1 - MOVW arg+4(FP), R2 - MOVW R1, 0(R13) - MOVW R2, 4(R13) - BL runtime·asmcgocall_errno(SB) + MOVW arg+4(FP), R0 + BL asmcgocall<>(SB) RET TEXT runtime·asmcgocall_errno(SB),NOSPLIT,$0-12 MOVW fn+0(FP), R1 MOVW arg+4(FP), R0 + BL asmcgocall<>(SB) + MOVW R0, ret+8(FP) + RET + +TEXT asmcgocall<>(SB),NOSPLIT,$0-0 + // fn in R1, arg in R0. MOVW R13, R2 MOVW g, R5 @@ -529,7 +533,6 @@ TEXT runtime·asmcgocall_errno(SB),NOSPLIT,$0-12 // Restore registers, g, stack pointer. MOVW 20(R13), g MOVW 16(R13), R13 - MOVW R0, ret+8(FP) RET // cgocallback(void (*fn)(void*), void *frame, uintptr framesize) |