diff options
Diffstat (limited to 'src/cmd/compile/internal/ssa/_gen/RISCV64Ops.go')
| -rw-r--r-- | src/cmd/compile/internal/ssa/_gen/RISCV64Ops.go | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/src/cmd/compile/internal/ssa/_gen/RISCV64Ops.go b/src/cmd/compile/internal/ssa/_gen/RISCV64Ops.go index a0e1ab9754..68674211b0 100644 --- a/src/cmd/compile/internal/ssa/_gen/RISCV64Ops.go +++ b/src/cmd/compile/internal/ssa/_gen/RISCV64Ops.go @@ -118,6 +118,7 @@ func init() { regCtxt := regNamed["X26"] callerSave := gpMask | fpMask | regNamed["g"] r5toR6 := regNamed["X5"] | regNamed["X6"] + regX5 := regNamed["X5"] var ( gpstore = regInfo{inputs: []regMask{gpspsbMask, gpspMask, 0}} // SB in first input so we can load from a global, but not in second to avoid using SB as a temporary register @@ -142,9 +143,13 @@ func init() { fpload = regInfo{inputs: []regMask{gpspsbMask, 0}, outputs: []regMask{fpMask}} fp2gp = regInfo{inputs: []regMask{fpMask, fpMask}, outputs: []regMask{gpMask}} - call = regInfo{clobbers: callerSave} - callClosure = regInfo{inputs: []regMask{gpspMask, regCtxt, 0}, clobbers: callerSave} - callInter = regInfo{inputs: []regMask{gpMask}, clobbers: callerSave} + call = regInfo{clobbers: callerSave} + // Avoid using X5 as the source register of calls. Using X5 here triggers + // RAS pop-then-push behavior which is not correct for function calls. + // Please refer to section 2.5.1 of the RISC-V ISA + // (https://docs.riscv.org/reference/isa/unpriv/rv32.html#rashints) for details. + callClosure = regInfo{inputs: []regMask{gpspMask ^ regX5, regCtxt, 0}, clobbers: callerSave} + callInter = regInfo{inputs: []regMask{gpMask ^ regX5}, clobbers: callerSave} ) RISCV64ops := []opData{ |