shader: Fix instruction transitions in and out of Phi

This commit is contained in:
ReinUsesLisp 2021-03-17 01:30:23 -03:00 committed by ameerj
parent fa2f6e38f4
commit 8dd0acfaeb

View file

@ -182,7 +182,7 @@ void Inst::AddPhiOperand(Block* predecessor, const Value& value) {
void Inst::Invalidate() { void Inst::Invalidate() {
ClearArgs(); ClearArgs();
op = Opcode::Void; ReplaceOpcode(Opcode::Void);
} }
void Inst::ClearArgs() { void Inst::ClearArgs() {
@ -206,20 +206,22 @@ void Inst::ClearArgs() {
void Inst::ReplaceUsesWith(Value replacement) { void Inst::ReplaceUsesWith(Value replacement) {
Invalidate(); Invalidate();
ReplaceOpcode(Opcode::Identity);
op = Opcode::Identity;
if (!replacement.IsImmediate()) { if (!replacement.IsImmediate()) {
Use(replacement); Use(replacement);
} }
if (op == Opcode::Phi) {
phi_args[0].second = replacement;
} else {
args[0] = replacement; args[0] = replacement;
}
} }
void Inst::ReplaceOpcode(IR::Opcode opcode) { void Inst::ReplaceOpcode(IR::Opcode opcode) {
if (opcode == IR::Opcode::Phi) {
throw LogicError("Cannot transition into Phi");
}
if (op == Opcode::Phi) {
// Transition out of phi arguments into non-phi
std::destroy_at(&phi_args);
std::construct_at(&args);
}
op = opcode; op = opcode;
} }