diff --git a/src/cmd/compile/internal/ssa/regalloc.go b/src/cmd/compile/internal/ssa/regalloc.go index c81d5574fe..3b90b8769c 100644 --- a/src/cmd/compile/internal/ssa/regalloc.go +++ b/src/cmd/compile/internal/ssa/regalloc.go @@ -1882,6 +1882,10 @@ func (s *regAllocState) placeSpills() { phiRegs[b.ID] = m } + mustBeFirst := func(op Op) bool { + return op.isLoweredGetClosurePtr() || op == OpPhi || op == OpArgIntReg || op == OpArgFloatReg + } + // Start maps block IDs to the list of spills // that go at the start of the block (but after any phis). start := map[ID][]*Value{} @@ -1971,7 +1975,7 @@ func (s *regAllocState) placeSpills() { // Put the spill in the best block we found. spill.Block = best spill.AddArg(bestArg) - if best == v.Block && v.Op != OpPhi { + if best == v.Block && !mustBeFirst(v.Op) { // Place immediately after v. after[v.ID] = append(after[v.ID], spill) } else { @@ -1983,15 +1987,15 @@ func (s *regAllocState) placeSpills() { // Insert spill instructions into the block schedules. var oldSched []*Value for _, b := range s.visitOrder { - nphi := 0 + nfirst := 0 for _, v := range b.Values { - if v.Op != OpPhi { + if !mustBeFirst(v.Op) { break } - nphi++ + nfirst++ } - oldSched = append(oldSched[:0], b.Values[nphi:]...) - b.Values = b.Values[:nphi] + oldSched = append(oldSched[:0], b.Values[nfirst:]...) + b.Values = b.Values[:nfirst] b.Values = append(b.Values, start[b.ID]...) for _, v := range oldSched { b.Values = append(b.Values, v)