glsl: Fix "reg" allocing

based on glasm with some tweaks

1 files changed, 28 insertions, 0 deletions

diff --git a/src/shader_recompiler/backend/glsl/emit_glsl_bitwise_conversion.cpp b/src/shader_recompiler/backend/glsl/emit_glsl_bitwise_conversion.cpp
index e69de29bb..7c654e4e7 100644
--- a/src/shader_recompiler/backend/glsl/emit_glsl_bitwise_conversion.cpp
+++ b/src/shader_recompiler/backend/glsl/emit_glsl_bitwise_conversion.cpp
@@ -0,0 +1,28 @@
+// Copyright 2021 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <string_view>
+
+#include "shader_recompiler/backend/glsl/emit_context.h"
+#include "shader_recompiler/backend/glsl/emit_glsl_instructions.h"
+#include "shader_recompiler/frontend/ir/value.h"
+#include "shader_recompiler/profile.h"
+
+namespace Shader::Backend::GLSL {
+namespace {
+static void Alias(IR::Inst& inst, const IR::Value& value) {
+    if (value.IsImmediate()) {
+        return;
+    }
+    IR::Inst& value_inst{RegAlloc::AliasInst(*value.Inst())};
+    value_inst.DestructiveAddUsage(inst.UseCount());
+    value_inst.DestructiveRemoveUsage();
+    inst.SetDefinition(value_inst.Definition<Id>());
+}
+} // namespace
+
+void EmitIdentity(EmitContext&, IR::Inst* inst, const IR::Value& value) {
+    Alias(*inst, value);
+}
+} // namespace Shader::Backend::GLSL