diff options
Diffstat (limited to 'src/runtime/asm_wasm.s')
| -rw-r--r-- | src/runtime/asm_wasm.s | 64 |
1 files changed, 45 insertions, 19 deletions
diff --git a/src/runtime/asm_wasm.s b/src/runtime/asm_wasm.s index e108bb4362..330c10cc0c 100644 --- a/src/runtime/asm_wasm.s +++ b/src/runtime/asm_wasm.s @@ -404,12 +404,15 @@ TEXT runtime·goexit(SB), NOSPLIT|TOPFRAME, $0-0 TEXT runtime·cgocallback(SB), NOSPLIT, $0-24 UNDEF -// gcWriteBarrier performs a heap pointer write and informs the GC. +// gcWriteBarrier informs the GC about heap pointer writes. // -// gcWriteBarrier does NOT follow the Go ABI. It has two WebAssembly parameters: -// R0: the destination of the write (i64) -// R1: the value being written (i64) -TEXT runtime·gcWriteBarrier(SB), NOSPLIT, $16 +// gcWriteBarrier does NOT follow the Go ABI. It accepts the +// number of bytes of buffer needed as a wasm argument +// (put on the TOS by the caller, lives in local R0 in this body) +// and returns a pointer to the buffer space as a wasm result +// (left on the TOS in this body, appears on the wasm stack +// in the caller). +TEXT gcWriteBarrier<>(SB), NOSPLIT, $0 Loop // R3 = g.m MOVD g_m(g), R3 @@ -420,7 +423,7 @@ TEXT runtime·gcWriteBarrier(SB), NOSPLIT, $16 // Increment wbBuf.next Get R5 - I64Const $16 + Get R0 I64Add Set R5 @@ -432,27 +435,50 @@ TEXT runtime·gcWriteBarrier(SB), NOSPLIT, $16 // Commit to the larger buffer. MOVD R5, p_wbBuf+wbBuf_next(R4) - // Back up to write position (wasm stores can't use negative offsets) + // Make return value (the original next position) Get R5 - I64Const $16 + Get R0 I64Sub - Set R5 - // Record value - MOVD R1, 0(R5) - // Record *slot - MOVD (R0), 8(R5) - - RET + Return End // Flush - MOVD R0, 0(SP) - MOVD R1, 8(SP) CALLNORESUME runtime·wbBufFlush(SB) - MOVD 0(SP), R0 - MOVD 8(SP), R1 // Retry Br $0 End + +TEXT runtime·gcWriteBarrier1<ABIInternal>(SB),NOSPLIT,$0 + I64Const $8 + Call gcWriteBarrier<>(SB) + Return +TEXT runtime·gcWriteBarrier2<ABIInternal>(SB),NOSPLIT,$0 + I64Const $16 + Call gcWriteBarrier<>(SB) + Return +TEXT runtime·gcWriteBarrier3<ABIInternal>(SB),NOSPLIT,$0 + I64Const $24 + Call gcWriteBarrier<>(SB) + Return +TEXT runtime·gcWriteBarrier4<ABIInternal>(SB),NOSPLIT,$0 + I64Const $32 + Call gcWriteBarrier<>(SB) + Return +TEXT runtime·gcWriteBarrier5<ABIInternal>(SB),NOSPLIT,$0 + I64Const $40 + Call gcWriteBarrier<>(SB) + Return +TEXT runtime·gcWriteBarrier6<ABIInternal>(SB),NOSPLIT,$0 + I64Const $48 + Call gcWriteBarrier<>(SB) + Return +TEXT runtime·gcWriteBarrier7<ABIInternal>(SB),NOSPLIT,$0 + I64Const $56 + Call gcWriteBarrier<>(SB) + Return +TEXT runtime·gcWriteBarrier8<ABIInternal>(SB),NOSPLIT,$0 + I64Const $64 + Call gcWriteBarrier<>(SB) + Return |