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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-16 19:25:22 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-16 19:25:22 +0000 |
commit | f6ad4dcef54c5ce997a4bad5a6d86de229015700 (patch) | |
tree | 7cfa4e31ace5c2bd95c72b154d15af494b2bcbef /src/runtime/internal/atomic/atomic_riscv64.s | |
parent | Initial commit. (diff) | |
download | golang-1.22-f6ad4dcef54c5ce997a4bad5a6d86de229015700.tar.xz golang-1.22-f6ad4dcef54c5ce997a4bad5a6d86de229015700.zip |
Adding upstream version 1.22.1.upstream/1.22.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/runtime/internal/atomic/atomic_riscv64.s')
-rw-r--r-- | src/runtime/internal/atomic/atomic_riscv64.s | 324 |
1 files changed, 324 insertions, 0 deletions
diff --git a/src/runtime/internal/atomic/atomic_riscv64.s b/src/runtime/internal/atomic/atomic_riscv64.s new file mode 100644 index 0000000..bf6bd35 --- /dev/null +++ b/src/runtime/internal/atomic/atomic_riscv64.s @@ -0,0 +1,324 @@ +// Copyright 2014 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// RISC-V's atomic operations have two bits, aq ("acquire") and rl ("release"), +// which may be toggled on and off. Their precise semantics are defined in +// section 6.3 of the specification, but the basic idea is as follows: +// +// - If neither aq nor rl is set, the CPU may reorder the atomic arbitrarily. +// It guarantees only that it will execute atomically. +// +// - If aq is set, the CPU may move the instruction backward, but not forward. +// +// - If rl is set, the CPU may move the instruction forward, but not backward. +// +// - If both are set, the CPU may not reorder the instruction at all. +// +// These four modes correspond to other well-known memory models on other CPUs. +// On ARM, aq corresponds to a dmb ishst, aq+rl corresponds to a dmb ish. On +// Intel, aq corresponds to an lfence, rl to an sfence, and aq+rl to an mfence +// (or a lock prefix). +// +// Go's memory model requires that +// - if a read happens after a write, the read must observe the write, and +// that +// - if a read happens concurrently with a write, the read may observe the +// write. +// aq is sufficient to guarantee this, so that's what we use here. (This jibes +// with ARM, which uses dmb ishst.) + +#include "textflag.h" + +// func Cas(ptr *uint64, old, new uint64) bool +// Atomically: +// if(*val == old){ +// *val = new; +// return 1; +// } else { +// return 0; +// } +TEXT ·Cas(SB), NOSPLIT, $0-17 + MOV ptr+0(FP), A0 + MOVW old+8(FP), A1 + MOVW new+12(FP), A2 +cas_again: + LRW (A0), A3 + BNE A3, A1, cas_fail + SCW A2, (A0), A4 + BNE A4, ZERO, cas_again + MOV $1, A0 + MOVB A0, ret+16(FP) + RET +cas_fail: + MOV $0, A0 + MOV A0, ret+16(FP) + RET + +// func Cas64(ptr *uint64, old, new uint64) bool +TEXT ·Cas64(SB), NOSPLIT, $0-25 + MOV ptr+0(FP), A0 + MOV old+8(FP), A1 + MOV new+16(FP), A2 +cas_again: + LRD (A0), A3 + BNE A3, A1, cas_fail + SCD A2, (A0), A4 + BNE A4, ZERO, cas_again + MOV $1, A0 + MOVB A0, ret+24(FP) + RET +cas_fail: + MOVB ZERO, ret+24(FP) + RET + +// func Load(ptr *uint32) uint32 +TEXT ·Load(SB),NOSPLIT|NOFRAME,$0-12 + MOV ptr+0(FP), A0 + LRW (A0), A0 + MOVW A0, ret+8(FP) + RET + +// func Load8(ptr *uint8) uint8 +TEXT ·Load8(SB),NOSPLIT|NOFRAME,$0-9 + MOV ptr+0(FP), A0 + FENCE + MOVBU (A0), A1 + FENCE + MOVB A1, ret+8(FP) + RET + +// func Load64(ptr *uint64) uint64 +TEXT ·Load64(SB),NOSPLIT|NOFRAME,$0-16 + MOV ptr+0(FP), A0 + LRD (A0), A0 + MOV A0, ret+8(FP) + RET + +// func Store(ptr *uint32, val uint32) +TEXT ·Store(SB), NOSPLIT, $0-12 + MOV ptr+0(FP), A0 + MOVW val+8(FP), A1 + AMOSWAPW A1, (A0), ZERO + RET + +// func Store8(ptr *uint8, val uint8) +TEXT ·Store8(SB), NOSPLIT, $0-9 + MOV ptr+0(FP), A0 + MOVBU val+8(FP), A1 + FENCE + MOVB A1, (A0) + FENCE + RET + +// func Store64(ptr *uint64, val uint64) +TEXT ·Store64(SB), NOSPLIT, $0-16 + MOV ptr+0(FP), A0 + MOV val+8(FP), A1 + AMOSWAPD A1, (A0), ZERO + RET + +TEXT ·Casp1(SB), NOSPLIT, $0-25 + JMP ·Cas64(SB) + +TEXT ·Casint32(SB),NOSPLIT,$0-17 + JMP ·Cas(SB) + +TEXT ·Casint64(SB),NOSPLIT,$0-25 + JMP ·Cas64(SB) + +TEXT ·Casuintptr(SB),NOSPLIT,$0-25 + JMP ·Cas64(SB) + +TEXT ·CasRel(SB), NOSPLIT, $0-17 + JMP ·Cas(SB) + +TEXT ·Loaduintptr(SB),NOSPLIT,$0-16 + JMP ·Load64(SB) + +TEXT ·Storeint32(SB),NOSPLIT,$0-12 + JMP ·Store(SB) + +TEXT ·Storeint64(SB),NOSPLIT,$0-16 + JMP ·Store64(SB) + +TEXT ·Storeuintptr(SB),NOSPLIT,$0-16 + JMP ·Store64(SB) + +TEXT ·Loaduint(SB),NOSPLIT,$0-16 + JMP ·Loaduintptr(SB) + +TEXT ·Loadint32(SB),NOSPLIT,$0-12 + JMP ·Load(SB) + +TEXT ·Loadint64(SB),NOSPLIT,$0-16 + JMP ·Load64(SB) + +TEXT ·Xaddint32(SB),NOSPLIT,$0-20 + JMP ·Xadd(SB) + +TEXT ·Xaddint64(SB),NOSPLIT,$0-24 + MOV ptr+0(FP), A0 + MOV delta+8(FP), A1 + AMOADDD A1, (A0), A0 + ADD A0, A1, A0 + MOVW A0, ret+16(FP) + RET + +TEXT ·LoadAcq(SB),NOSPLIT|NOFRAME,$0-12 + JMP ·Load(SB) + +TEXT ·LoadAcq64(SB),NOSPLIT|NOFRAME,$0-16 + JMP ·Load64(SB) + +TEXT ·LoadAcquintptr(SB),NOSPLIT|NOFRAME,$0-16 + JMP ·Load64(SB) + +// func Loadp(ptr unsafe.Pointer) unsafe.Pointer +TEXT ·Loadp(SB),NOSPLIT,$0-16 + JMP ·Load64(SB) + +// func StorepNoWB(ptr unsafe.Pointer, val unsafe.Pointer) +TEXT ·StorepNoWB(SB), NOSPLIT, $0-16 + JMP ·Store64(SB) + +TEXT ·StoreRel(SB), NOSPLIT, $0-12 + JMP ·Store(SB) + +TEXT ·StoreRel64(SB), NOSPLIT, $0-16 + JMP ·Store64(SB) + +TEXT ·StoreReluintptr(SB), NOSPLIT, $0-16 + JMP ·Store64(SB) + +// func Xchg(ptr *uint32, new uint32) uint32 +TEXT ·Xchg(SB), NOSPLIT, $0-20 + MOV ptr+0(FP), A0 + MOVW new+8(FP), A1 + AMOSWAPW A1, (A0), A1 + MOVW A1, ret+16(FP) + RET + +// func Xchg64(ptr *uint64, new uint64) uint64 +TEXT ·Xchg64(SB), NOSPLIT, $0-24 + MOV ptr+0(FP), A0 + MOV new+8(FP), A1 + AMOSWAPD A1, (A0), A1 + MOV A1, ret+16(FP) + RET + +// Atomically: +// *val += delta; +// return *val; + +// func Xadd(ptr *uint32, delta int32) uint32 +TEXT ·Xadd(SB), NOSPLIT, $0-20 + MOV ptr+0(FP), A0 + MOVW delta+8(FP), A1 + AMOADDW A1, (A0), A2 + ADD A2,A1,A0 + MOVW A0, ret+16(FP) + RET + +// func Xadd64(ptr *uint64, delta int64) uint64 +TEXT ·Xadd64(SB), NOSPLIT, $0-24 + MOV ptr+0(FP), A0 + MOV delta+8(FP), A1 + AMOADDD A1, (A0), A2 + ADD A2, A1, A0 + MOV A0, ret+16(FP) + RET + +// func Xadduintptr(ptr *uintptr, delta uintptr) uintptr +TEXT ·Xadduintptr(SB), NOSPLIT, $0-24 + JMP ·Xadd64(SB) + +// func Xchgint32(ptr *int32, new int32) int32 +TEXT ·Xchgint32(SB), NOSPLIT, $0-20 + JMP ·Xchg(SB) + +// func Xchgint64(ptr *int64, new int64) int64 +TEXT ·Xchgint64(SB), NOSPLIT, $0-24 + JMP ·Xchg64(SB) + +// func Xchguintptr(ptr *uintptr, new uintptr) uintptr +TEXT ·Xchguintptr(SB), NOSPLIT, $0-24 + JMP ·Xchg64(SB) + +// func And8(ptr *uint8, val uint8) +TEXT ·And8(SB), NOSPLIT, $0-9 + MOV ptr+0(FP), A0 + MOVBU val+8(FP), A1 + AND $3, A0, A2 + AND $-4, A0 + SLL $3, A2 + XOR $255, A1 + SLL A2, A1 + XOR $-1, A1 + AMOANDW A1, (A0), ZERO + RET + +// func Or8(ptr *uint8, val uint8) +TEXT ·Or8(SB), NOSPLIT, $0-9 + MOV ptr+0(FP), A0 + MOVBU val+8(FP), A1 + AND $3, A0, A2 + AND $-4, A0 + SLL $3, A2 + SLL A2, A1 + AMOORW A1, (A0), ZERO + RET + +// func And(ptr *uint32, val uint32) +TEXT ·And(SB), NOSPLIT, $0-12 + MOV ptr+0(FP), A0 + MOVW val+8(FP), A1 + AMOANDW A1, (A0), ZERO + RET + +// func Or(ptr *uint32, val uint32) +TEXT ·Or(SB), NOSPLIT, $0-12 + MOV ptr+0(FP), A0 + MOVW val+8(FP), A1 + AMOORW A1, (A0), ZERO + RET + +// func Or32(ptr *uint32, val uint32) uint32 +TEXT ·Or32(SB), NOSPLIT, $0-20 + MOV ptr+0(FP), A0 + MOVW val+8(FP), A1 + AMOORW A1, (A0), A2 + MOVW A2, ret+16(FP) + RET + +// func And32(ptr *uint32, val uint32) uint32 +TEXT ·And32(SB), NOSPLIT, $0-20 + MOV ptr+0(FP), A0 + MOVW val+8(FP), A1 + AMOANDW A1, (A0), A2 + MOVW A2, ret+16(FP) + RET + +// func Or64(ptr *uint64, val uint64) uint64 +TEXT ·Or64(SB), NOSPLIT, $0-24 + MOV ptr+0(FP), A0 + MOV val+8(FP), A1 + AMOORD A1, (A0), A2 + MOV A2, ret+16(FP) + RET + +// func And64(ptr *uint64, val uint64) uint64 +TEXT ·And64(SB), NOSPLIT, $0-24 + MOV ptr+0(FP), A0 + MOV val+8(FP), A1 + AMOANDD A1, (A0), A2 + MOV A2, ret+16(FP) + RET + +// func Anduintptr(ptr *uintptr, val uintptr) uintptr +TEXT ·Anduintptr(SB), NOSPLIT, $0-24 + JMP ·And64(SB) + +// func Oruintptr(ptr *uintptr, val uintptr) uintptr +TEXT ·Oruintptr(SB), NOSPLIT, $0-24 + JMP ·Or64(SB) |