1 files changed, 73 insertions, 3 deletions

diff --git a/src/shader_recompiler/ir_opt/constant_propagation_pass.cpp b/src/shader_recompiler/ir_opt/constant_propagation_pass.cpp
index 826f9a54a..4d81e9336 100644
--- a/src/shader_recompiler/ir_opt/constant_propagation_pass.cpp
+++ b/src/shader_recompiler/ir_opt/constant_propagation_pass.cpp
@@ -7,6 +7,7 @@
 #include <type_traits>
 
 #include "common/bit_cast.h"
+#include "shader_recompiler/environment.h"
 #include "shader_recompiler/exception.h"
 #include "shader_recompiler/frontend/ir/ir_emitter.h"
 #include "shader_recompiler/frontend/ir/value.h"
@@ -515,6 +516,9 @@ void FoldBitCast(IR::Inst& inst, IR::Opcode reverse) {
             case IR::Attribute::PrimitiveId:
             case IR::Attribute::InstanceId:
             case IR::Attribute::VertexId:
+            case IR::Attribute::BaseVertex:
+            case IR::Attribute::BaseInstance:
+            case IR::Attribute::DrawID:
                 break;
             default:
                 return;
@@ -644,7 +648,63 @@ void FoldFSwizzleAdd(IR::Block& block, IR::Inst& inst) {
     }
 }
 
-void ConstantPropagation(IR::Block& block, IR::Inst& inst) {
+void FoldConstBuffer(Environment& env, IR::Block& block, IR::Inst& inst) {
+    const IR::Value bank{inst.Arg(0)};
+    const IR::Value offset{inst.Arg(1)};
+    if (!bank.IsImmediate() || !offset.IsImmediate()) {
+        return;
+    }
+    const auto bank_value = bank.U32();
+    const auto offset_value = offset.U32();
+    auto replacement = env.GetReplaceConstBuffer(bank_value, offset_value);
+    if (!replacement) {
+        return;
+    }
+    const auto new_attribute = [replacement]() {
+        switch (*replacement) {
+        case ReplaceConstant::BaseInstance:
+            return IR::Attribute::BaseInstance;
+        case ReplaceConstant::BaseVertex:
+            return IR::Attribute::BaseVertex;
+        case ReplaceConstant::DrawID:
+            return IR::Attribute::DrawID;
+        default:
+            throw NotImplementedException("Not implemented replacement variable {}", *replacement);
+        }
+    }();
+    IR::IREmitter ir{block, IR::Block::InstructionList::s_iterator_to(inst)};
+    if (inst.GetOpcode() == IR::Opcode::GetCbufU32) {
+        inst.ReplaceUsesWith(ir.GetAttributeU32(new_attribute));
+    } else {
+        inst.ReplaceUsesWith(ir.GetAttribute(new_attribute));
+    }
+}
+
+void FoldDriverConstBuffer(Environment& env, IR::Block& block, IR::Inst& inst, u32 which_bank,
+                           u32 offset_start = 0, u32 offset_end = std::numeric_limits<u16>::max()) {
+    const IR::Value bank{inst.Arg(0)};
+    const IR::Value offset{inst.Arg(1)};
+    if (!bank.IsImmediate() || !offset.IsImmediate()) {
+        return;
+    }
+    const auto bank_value = bank.U32();
+    if (bank_value != which_bank) {
+        return;
+    }
+    const auto offset_value = offset.U32();
+    if (offset_value < offset_start || offset_value >= offset_end) {
+        return;
+    }
+    IR::IREmitter ir{block, IR::Block::InstructionList::s_iterator_to(inst)};
+    if (inst.GetOpcode() == IR::Opcode::GetCbufU32) {
+        inst.ReplaceUsesWith(IR::Value{env.ReadCbufValue(bank_value, offset_value)});
+    } else {
+        inst.ReplaceUsesWith(
+            IR::Value{Common::BitCast<f32>(env.ReadCbufValue(bank_value, offset_value))});
+    }
+}
+
+void ConstantPropagation(Environment& env, IR::Block& block, IR::Inst& inst) {
     switch (inst.GetOpcode()) {
     case IR::Opcode::GetRegister:
         return FoldGetRegister(inst);
@@ -789,18 +849,28 @@ void ConstantPropagation(IR::Block& block, IR::Inst& inst) {
                                     IR::Opcode::CompositeInsertF16x4);
     case IR::Opcode::FSwizzleAdd:
         return FoldFSwizzleAdd(block, inst);
+    case IR::Opcode::GetCbufF32:
+    case IR::Opcode::GetCbufU32:
+        if (env.HasHLEMacroState()) {
+            FoldConstBuffer(env, block, inst);
+        }
+        if (env.IsPropietaryDriver()) {
+            FoldDriverConstBuffer(env, block, inst, 1);
+        }
+        break;
     default:
         break;
     }
 }
+
 } // Anonymous namespace
 
-void ConstantPropagationPass(IR::Program& program) {
+void ConstantPropagationPass(Environment& env, IR::Program& program) {
     const auto end{program.post_order_blocks.rend()};
     for (auto it = program.post_order_blocks.rbegin(); it != end; ++it) {
         IR::Block* const block{*it};
         for (IR::Inst& inst : block->Instructions()) {
-            ConstantPropagation(*block, inst);
+            ConstantPropagation(env, *block, inst);
         }
     }
 }