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| author | Cherry Mui <cherryyz@google.com> | 2024-04-22 17:40:53 -0400 |
|---|---|---|
| committer | Cherry Mui <cherryyz@google.com> | 2024-04-22 22:46:08 +0000 |
| commit | 0c39dc1ff72181d36f7e9fc61bfacc5a7b7c5c57 (patch) | |
| tree | a11cc8d74f1aacea5f222e5fbd629a82e170c405 | |
| parent | 552faa8927a23fd5967435295c14af1741ac3653 (diff) | |
| download | go-0c39dc1ff72181d36f7e9fc61bfacc5a7b7c5c57.tar.gz go-0c39dc1ff72181d36f7e9fc61bfacc5a7b7c5c57.zip | |
runtime: reduce stack usage for asmcgocall on PPC64
Define it as ABIInternal, so the result does not take space on
stack.
Also use R10 as a temporary register for arithmetics on SP, so it
is hidden from the assembler's SP delta calculation, which is
irrelevant anyway as we are on the system stack.
Change-Id: I8fed467601c19cad2d7afab26978246d15ce3147
Reviewed-on: https://go-review.googlesource.com/c/go/+/580918
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Cherry Mui <cherryyz@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
| -rw-r--r-- | src/runtime/asm_ppc64x.s | 21 |
1 files changed, 12 insertions, 9 deletions
diff --git a/src/runtime/asm_ppc64x.s b/src/runtime/asm_ppc64x.s index ff9b736430..97c2a370bd 100644 --- a/src/runtime/asm_ppc64x.s +++ b/src/runtime/asm_ppc64x.s @@ -615,9 +615,9 @@ TEXT ·asmcgocall_no_g(SB),NOSPLIT,$0-16 // Call fn(arg) on the scheduler stack, // aligned appropriately for the gcc ABI. // See cgocall.go for more details. -TEXT ·asmcgocall(SB),NOSPLIT,$0-20 - MOVD fn+0(FP), R3 - MOVD arg+8(FP), R4 +TEXT ·asmcgocall<ABIInternal>(SB),NOSPLIT,$0-20 + // R3 = fn + // R4 = arg MOVD R1, R7 // save original stack pointer CMP $0, g @@ -651,8 +651,11 @@ TEXT ·asmcgocall(SB),NOSPLIT,$0-20 #endif // Save room for two of our pointers, plus the callee // save area that lives on the caller stack. - SUB $(asmcgocallSaveOffset+16), R1 - RLDCR $0, R1, $~15, R1 // 16-byte alignment for gcc ABI + // Do arithmetics in R10 to hide from the assembler + // counting it as SP delta, which is irrelevant as we are + // on the system stack. + SUB $(asmcgocallSaveOffset+16), R1, R10 + RLDCR $0, R10, $~15, R1 // 16-byte alignment for gcc ABI MOVD R5, (asmcgocallSaveOffset+8)(R1) // save old g on stack MOVD (g_stack+stack_hi)(R5), R5 SUB R7, R5 @@ -689,7 +692,7 @@ TEXT ·asmcgocall(SB),NOSPLIT,$0-20 MOVD R5, R1 BL runtime·save_g(SB) - MOVW R3, ret+16(FP) + // ret = R3 RET nosave: @@ -703,8 +706,8 @@ nosave: // Using this code for all "already on system stack" calls exercises it more, // which should help keep it correct. - SUB $(asmcgocallSaveOffset+8), R1 - RLDCR $0, R1, $~15, R1 // 16-byte alignment for gcc ABI + SUB $(asmcgocallSaveOffset+8), R1, R10 + RLDCR $0, R10, $~15, R1 // 16-byte alignment for gcc ABI MOVD R7, asmcgocallSaveOffset(R1) // Save original stack pointer. MOVD R3, R12 // fn @@ -724,7 +727,7 @@ nosave: #ifndef GOOS_aix MOVD 24(R1), R2 #endif - MOVW R3, ret+16(FP) + // ret = R3 RET // func cgocallback(fn, frame unsafe.Pointer, ctxt uintptr) |