From c788f9c0bd9cb0b0cb66f7424a65032cca3731cc Mon Sep 17 00:00:00 2001
From: ReinUsesLisp <reinuseslisp@airmail.cc>
Date: Sat, 25 Apr 2020 22:41:20 -0300
Subject: [PATCH] shader/arithmetic_integer: Implement IADD.X
IADD.X takes the carry flag and adds it to the result. This is generally
used to emulate 64-bit operations with 32-bit registers.
---
src/video_core/engines/shader_bytecode.h | 4 ++++
src/video_core/shader/decode/arithmetic_integer.cpp | 6 ++++++
2 files changed, 10 insertions(+)
diff --git a/src/video_core/engines/shader_bytecode.h b/src/video_core/engines/shader_bytecode.h
index cde3a26b9d..8dae754d49 100644
--- a/src/video_core/engines/shader_bytecode.h
+++ b/src/video_core/engines/shader_bytecode.h
@@ -813,6 +813,10 @@ union Instruction {
BitField<49, 1, u64> negate_a;
} alu_integer;
+ union {
+ BitField<43, 1, u64> x;
+ } iadd;
+
union {
BitField<39, 1, u64> ftz;
BitField<32, 1, u64> saturate;
diff --git a/src/video_core/shader/decode/arithmetic_integer.cpp b/src/video_core/shader/decode/arithmetic_integer.cpp
index 99b4b6342f..2a3311cb8e 100644
--- a/src/video_core/shader/decode/arithmetic_integer.cpp
+++ b/src/video_core/shader/decode/arithmetic_integer.cpp
@@ -42,6 +42,12 @@ u32 ShaderIR::DecodeArithmeticInteger(NodeBlock& bb, u32 pc) {
Node value = Operation(OperationCode::IAdd, 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));
+ }
+
if (instr.generates_cc) {
const Node i0 = Immediate(0);