3 files changed, 38 insertions, 2 deletions

diff --git a/src/video_core/shader/node.h b/src/video_core/shader/node.h
index 4d2f4d6a8..4e155542a 100644
--- a/src/video_core/shader/node.h
+++ b/src/video_core/shader/node.h
@@ -392,8 +392,30 @@ struct MetaImage {
 using Meta =
     std::variant<MetaArithmetic, MetaTexture, MetaImage, MetaStackClass, Tegra::Shader::HalfType>;
 
+class AmendNode {
+public:
+    std::optional<std::size_t> GetAmendIndex() const {
+        if (amend_index == amend_null_index) {
+            return std::nullopt;
+        }
+        return {amend_index};
+    }
+
+    void SetAmendIndex(std::size_t index) {
+        amend_index = index;
+    }
+
+    void ClearAmend() {
+        amend_index = amend_null_index;
+    }
+
+private:
+    static constexpr std::size_t amend_null_index = 0xFFFFFFFFFFFFFFFFULL;
+    std::size_t amend_index{amend_null_index};
+};
+
 /// Holds any kind of operation that can be done in the IR
-class OperationNode final {
+class OperationNode final : public AmendNode {
 public:
     explicit OperationNode(OperationCode code) : OperationNode(code, Meta{}) {}
 
@@ -433,7 +455,7 @@ private:
 };
 
 /// Encloses inside any kind of node that returns a boolean conditionally-executed code
-class ConditionalNode final {
+class ConditionalNode final : public AmendNode {
 public:
     explicit ConditionalNode(Node condition, std::vector<Node>&& code)
         : condition{std::move(condition)}, code{std::move(code)} {}
diff --git a/src/video_core/shader/shader_ir.cpp b/src/video_core/shader/shader_ir.cpp
index 1d9825c76..31eecb3f4 100644
--- a/src/video_core/shader/shader_ir.cpp
+++ b/src/video_core/shader/shader_ir.cpp
@@ -446,4 +446,10 @@ Node ShaderIR::BitfieldInsert(Node base, Node insert, u32 offset, u32 bits) {
                      Immediate(bits));
 }
 
+std::size_t ShaderIR::DeclareAmend(Node new_amend) {
+    const std::size_t id = amend_code.size();
+    amend_code.push_back(new_amend);
+    return id;
+}
+
 } // namespace VideoCommon::Shader
diff --git a/src/video_core/shader/shader_ir.h b/src/video_core/shader/shader_ir.h
index baed06ccd..aacd0a0da 100644
--- a/src/video_core/shader/shader_ir.h
+++ b/src/video_core/shader/shader_ir.h
@@ -176,6 +176,10 @@ public:
     /// Returns a condition code evaluated from internal flags
     Node GetConditionCode(Tegra::Shader::ConditionCode cc) const;
 
+    const Node& GetAmendNode(std::size_t index) const {
+        return amend_code[index];
+    }
+
 private:
     friend class ASTDecoder;
 
@@ -392,6 +396,9 @@ private:
                                                                Tegra::Shader::Instruction instr,
                                                                bool is_write);
 
+    /// Register new amending code and obtain the reference id.
+    std::size_t DeclareAmend(Node new_amend);
+
     const ProgramCode& program_code;
     const u32 main_offset;
     const CompilerSettings settings;
@@ -406,6 +413,7 @@ private:
     std::map<u32, NodeBlock> basic_blocks;
     NodeBlock global_code;
     ASTManager program_manager{true, true};
+    std::vector<Node> amend_code;
 
     std::set<u32> used_registers;
     std::set<Tegra::Shader::Pred> used_predicates;