gpu: implement mrtz exp target

rpcsx/gpu/lib/gcn-shader/include/shader/SpvConverter.hpp

@@ -17,6 +17,7 @@ struct Context : ir::Context {
   ir::Value perVertex;
   std::map<int, ir::Value> outputs;
   std::map<int, ir::Value> inputs;
+  ir::Value fragDepth;
 
   ir::RegionLike localVariables;
   ir::RegionLike epilogue;
@@ -151,5 +152,7 @@ struct Context : ir::Context {
   ir::Value createOutput(ir::Location loc, int index);
   ir::Value createInput(ir::Location loc, int index);
   ir::Value createAttr(ir::Location loc, int attrId, bool perVertex, bool flat);
+
+  ir::Value createFragDepth(ir::Location loc);
 };
 } // namespace shader::spv

rpcsx/gpu/lib/gcn-shader/src/GcnConverter.cpp

@@ -9,6 +9,7 @@
 #include "rx/die.hpp"
 #include <iostream>
 #include <limits>
+#include <print>
 
 using namespace shader;
 
@@ -651,9 +652,9 @@ static void expToSpv(GcnConverter &converter, gcn::Stage stage,
         continue;
       }
 
-      auto src =
-          builder.createSpvBitcast(loc, context.getTypeFloat32(),
-                                   inst.getOperand(operandIndex++).getAsValue());
+      auto src = builder.createSpvBitcast(
+          loc, context.getTypeFloat32(),
+          inst.getOperand(operandIndex++).getAsValue());
 
       auto srcType = src.getOperand(0).getAsValue();
       ir::Value elementType;
@@ -786,6 +787,26 @@ static void expToSpv(GcnConverter &converter, gcn::Stage stage,
     return;
   }
 
+  if (target == ET_MRTZ) {
+    auto output = context.createFragDepth(loc);
+    auto channelType = context.getTypeFloat32();
+
+    for (int channel = 0; channel < 4; ++channel) {
+      if (~swizzle & (1 << channel)) {
+        continue;
+      }
+
+      auto channelValue =
+          builder.createSpvCompositeExtract(loc, elemType, value, {{channel}});
+      channelValue =
+          context.createCast(loc, builder, channelType, channelValue);
+      builder.createSpvStore(loc, output, channelValue);
+      break;
+    }
+
+    return;
+  }
+
   if (target >= ET_PARAM0 && target <= ET_PARAM31) {
     auto output = context.createOutput(loc, target - ET_PARAM0);
     auto floatT = context.getTypeFloat32();
@@ -849,8 +870,8 @@ static void expToSpv(GcnConverter &converter, gcn::Stage stage,
     return result;
   };
 
-  std::printf("exp target %s.%s\n", targetToString(target).c_str(),
-              swizzleToString(swizzle).c_str());
+  std::println(stderr, "exp target {}.{}", targetToString(target),
+               swizzleToString(swizzle));
   std::abort();
 }
 
@@ -1454,6 +1475,8 @@ static void createEntryPoint(gcn::Context &context, const gcn::Environment &env,
     executionModes.createSpvExecutionMode(
         mainFn.getLocation(), mainFn,
         ir::spv::ExecutionMode::OriginUpperLeft());
+    executionModes.createSpvExecutionMode(
+        mainFn.getLocation(), mainFn, ir::spv::ExecutionMode::DepthReplacing());
   }
 
   if (executionModel == ir::spv::ExecutionModel::GLCompute) {

rpcsx/gpu/lib/gcn-shader/src/SpvConverter.cpp

@@ -571,8 +571,8 @@ ir::Value spv::Context::createOutput(ir::Location loc, int index) {
     auto annotations =
         Builder::createAppend(*this, layout.getOrCreateAnnotations(*this));
 
-    auto variable = globals.createSpvVariable(loc, variableType,
-                                              ir::spv::StorageClass::Output, nullValue);
+    auto variable = globals.createSpvVariable(
+        loc, variableType, ir::spv::StorageClass::Output, nullValue);
 
     annotations.createSpvDecorate(loc, variable,
                                   ir::spv::Decoration::Location(index));
@@ -647,3 +647,30 @@ ir::Value spv::Context::createAttr(ir::Location loc, int attrId, bool perVertex,
 
   return result;
 }
+
+ir::Value spv::Context::createFragDepth(ir::Location loc) {
+  if (fragDepth == nullptr) {
+    auto floatType = getTypeFloat32();
+    auto nullValue = getNull(floatType);
+
+    auto variableType =
+        getTypePointer(ir::spv::StorageClass::Output, floatType);
+
+    auto globals =
+        Builder::createAppend(*this, layout.getOrCreateGlobals(*this));
+    auto annotations =
+        Builder::createAppend(*this, layout.getOrCreateAnnotations(*this));
+
+    auto variable = globals.createSpvVariable(
+        loc, variableType, ir::spv::StorageClass::Output, nullValue);
+
+    annotations.createSpvDecorate(
+        loc, variable,
+        ir::spv::Decoration::BuiltIn(ir::spv::BuiltIn::FragDepth));
+
+    setName(variable, "fragDepth");
+    fragDepth = variable;
+  }
+
+  return fragDepth;
+}