shader: Misc fixes

This commit is contained in:
ReinUsesLisp 2021-02-14 01:24:32 -03:00 committed by ameerj
parent 9170200a11
commit 8af9297f09
10 changed files with 104 additions and 89 deletions

View file

@ -113,6 +113,7 @@ private:
IR::Value ReadVariableRecursive(auto variable, IR::Block* block) {
IR::Value val;
if (const std::span preds{block->ImmediatePredecessors()}; preds.size() == 1) {
// Optimize the common case of one predecessor: no phi needed
val = ReadVariable(variable, preds.front());
} else {
// Break potential cycles with operandless phi
@ -160,66 +161,70 @@ private:
DefTable current_def;
};
void VisitInst(Pass& pass, IR::Block* block, IR::Inst& inst) {
switch (inst.Opcode()) {
case IR::Opcode::SetRegister:
if (const IR::Reg reg{inst.Arg(0).Reg()}; reg != IR::Reg::RZ) {
pass.WriteVariable(reg, block, inst.Arg(1));
}
break;
case IR::Opcode::SetPred:
if (const IR::Pred pred{inst.Arg(0).Pred()}; pred != IR::Pred::PT) {
pass.WriteVariable(pred, block, inst.Arg(1));
}
break;
case IR::Opcode::SetGotoVariable:
pass.WriteVariable(GotoVariable{inst.Arg(0).U32()}, block, inst.Arg(1));
break;
case IR::Opcode::SetZFlag:
pass.WriteVariable(ZeroFlagTag{}, block, inst.Arg(0));
break;
case IR::Opcode::SetSFlag:
pass.WriteVariable(SignFlagTag{}, block, inst.Arg(0));
break;
case IR::Opcode::SetCFlag:
pass.WriteVariable(CarryFlagTag{}, block, inst.Arg(0));
break;
case IR::Opcode::SetOFlag:
pass.WriteVariable(OverflowFlagTag{}, block, inst.Arg(0));
break;
case IR::Opcode::GetRegister:
if (const IR::Reg reg{inst.Arg(0).Reg()}; reg != IR::Reg::RZ) {
inst.ReplaceUsesWith(pass.ReadVariable(reg, block));
}
break;
case IR::Opcode::GetPred:
if (const IR::Pred pred{inst.Arg(0).Pred()}; pred != IR::Pred::PT) {
inst.ReplaceUsesWith(pass.ReadVariable(pred, block));
}
break;
case IR::Opcode::GetGotoVariable:
inst.ReplaceUsesWith(pass.ReadVariable(GotoVariable{inst.Arg(0).U32()}, block));
break;
case IR::Opcode::GetZFlag:
inst.ReplaceUsesWith(pass.ReadVariable(ZeroFlagTag{}, block));
break;
case IR::Opcode::GetSFlag:
inst.ReplaceUsesWith(pass.ReadVariable(SignFlagTag{}, block));
break;
case IR::Opcode::GetCFlag:
inst.ReplaceUsesWith(pass.ReadVariable(CarryFlagTag{}, block));
break;
case IR::Opcode::GetOFlag:
inst.ReplaceUsesWith(pass.ReadVariable(OverflowFlagTag{}, block));
break;
default:
break;
}
}
} // Anonymous namespace
void SsaRewritePass(IR::Function& function) {
Pass pass;
for (IR::Block* const block : function.blocks) {
for (IR::Inst& inst : block->Instructions()) {
switch (inst.Opcode()) {
case IR::Opcode::SetRegister:
if (const IR::Reg reg{inst.Arg(0).Reg()}; reg != IR::Reg::RZ) {
pass.WriteVariable(reg, block, inst.Arg(1));
}
break;
case IR::Opcode::SetPred:
if (const IR::Pred pred{inst.Arg(0).Pred()}; pred != IR::Pred::PT) {
pass.WriteVariable(pred, block, inst.Arg(1));
}
break;
case IR::Opcode::SetGotoVariable:
pass.WriteVariable(GotoVariable{inst.Arg(0).U32()}, block, inst.Arg(1));
break;
case IR::Opcode::SetZFlag:
pass.WriteVariable(ZeroFlagTag{}, block, inst.Arg(0));
break;
case IR::Opcode::SetSFlag:
pass.WriteVariable(SignFlagTag{}, block, inst.Arg(0));
break;
case IR::Opcode::SetCFlag:
pass.WriteVariable(CarryFlagTag{}, block, inst.Arg(0));
break;
case IR::Opcode::SetOFlag:
pass.WriteVariable(OverflowFlagTag{}, block, inst.Arg(0));
break;
case IR::Opcode::GetRegister:
if (const IR::Reg reg{inst.Arg(0).Reg()}; reg != IR::Reg::RZ) {
inst.ReplaceUsesWith(pass.ReadVariable(reg, block));
}
break;
case IR::Opcode::GetPred:
if (const IR::Pred pred{inst.Arg(0).Pred()}; pred != IR::Pred::PT) {
inst.ReplaceUsesWith(pass.ReadVariable(pred, block));
}
break;
case IR::Opcode::GetGotoVariable:
inst.ReplaceUsesWith(pass.ReadVariable(GotoVariable{inst.Arg(0).U32()}, block));
break;
case IR::Opcode::GetZFlag:
inst.ReplaceUsesWith(pass.ReadVariable(ZeroFlagTag{}, block));
break;
case IR::Opcode::GetSFlag:
inst.ReplaceUsesWith(pass.ReadVariable(SignFlagTag{}, block));
break;
case IR::Opcode::GetCFlag:
inst.ReplaceUsesWith(pass.ReadVariable(CarryFlagTag{}, block));
break;
case IR::Opcode::GetOFlag:
inst.ReplaceUsesWith(pass.ReadVariable(OverflowFlagTag{}, block));
break;
default:
break;
}
VisitInst(pass, block, inst);
}
}
}