diff --git a/src/ir_opt/constant_propagation_pass.cpp b/src/ir_opt/constant_propagation_pass.cpp index 62d9bf01..5b9f7ac5 100644 --- a/src/ir_opt/constant_propagation_pass.cpp +++ b/src/ir_opt/constant_propagation_pass.cpp @@ -11,10 +11,42 @@ #include "ir_opt/passes.h" namespace Dynarmic::Optimization { +namespace { + +// Folds EOR operations based on: +// +// 1. imm_x ^ imm_y -> result +// 2. x ^ 0 -> x +// 3. 0 ^ y -> y +// +void FoldEOR(IR::Inst& inst, bool is_32_bit) { + const auto lhs = inst.GetArg(0); + const auto rhs = inst.GetArg(1); + + const bool is_lhs_immediate = lhs.IsImmediate(); + const bool is_rhs_immediate = rhs.IsImmediate(); + + if (is_lhs_immediate && is_rhs_immediate) { + const u64 result = lhs.GetImmediateAsU64() ^ rhs.GetImmediateAsU64(); + + if (is_32_bit) { + inst.ReplaceUsesWith(IR::Value{static_cast(result)}); + } else { + inst.ReplaceUsesWith(IR::Value{result}); + } + } else if (is_lhs_immediate && lhs.GetImmediateAsU64() == 0) { + inst.ReplaceUsesWith(rhs); + } else if (is_rhs_immediate && rhs.GetImmediateAsU64() == 0) { + inst.ReplaceUsesWith(lhs); + } +} +} // Anonymous namespace void ConstantPropagation(IR::Block& block) { for (auto& inst : block) { - switch (inst.GetOpcode()) { + const auto opcode = inst.GetOpcode(); + + switch (opcode) { case IR::Opcode::LogicalShiftLeft32: case IR::Opcode::LogicalShiftRight32: case IR::Opcode::ArithmeticShiftRight32: @@ -33,6 +65,10 @@ void ConstantPropagation(IR::Block& block) { } break; } + case IR::Opcode::Eor32: + case IR::Opcode::Eor64: + FoldEOR(inst, opcode == IR::Opcode::Eor32); + break; case IR::Opcode::ZeroExtendByteToWord: { if (!inst.AreAllArgsImmediates()) break;