shader/arithmetic_integer: Change IAdd to UAdd to avoid signed overflow

Signed integer addition overflow might be undefined behavior. It's free
to change operations to UAdd and use unsigned integers to avoid
potential bugs.
This commit is contained in:
ReinUsesLisp 2020-04-25 22:42:33 -03:00
parent 6404cd824b
commit 45cb8fc72a

View file

@ -40,12 +40,12 @@ u32 ShaderIR::DecodeArithmeticInteger(NodeBlock& bb, u32 pc) {
op_a = GetOperandAbsNegInteger(op_a, false, instr.alu_integer.negate_a, true);
op_b = GetOperandAbsNegInteger(op_b, false, instr.alu_integer.negate_b, true);
Node value = Operation(OperationCode::IAdd, op_a, op_b);
Node value = Operation(OperationCode::UAdd, op_a, op_b);
if (instr.iadd.x) {
Node carry = GetInternalFlag(InternalFlag::Carry);
Node x = Operation(OperationCode::Select, std::move(carry), Immediate(1), Immediate(0));
value = Operation(OperationCode::IAdd, std::move(value), std::move(x));
value = Operation(OperationCode::UAdd, std::move(value), std::move(x));
}
if (instr.generates_cc) {