[HLSL] Add support for input semantics in structs

clang/include/clang/Basic/DiagnosticFrontendKinds.td

@@ -404,6 +404,8 @@ def err_hlsl_semantic_missing : Error<"semantic annotations must be present "
                                       "for all input and outputs of an entry "
                                       "function or patch constant function">;
 
+def note_hlsl_semantic_used_here : Note<"%0 used here">;
+
 // ClangIR frontend errors
 def err_cir_to_cir_transform_failed : Error<
     "CIR-to-CIR transformation failed">, DefaultFatal;

clang/lib/CodeGen/CGHLSLRuntime.cpp

@@ -619,11 +619,51 @@ CGHLSLRuntime::handleScalarSemanticLoad(IRBuilder<> &B, llvm::Type *Type,
   return emitSystemSemanticLoad(B, Type, Decl, ActiveSemantic);
 }
 
+llvm::Value *
+CGHLSLRuntime::handleStructSemanticLoad(IRBuilder<> &B, llvm::Type *Type,
+                                        const clang::DeclaratorDecl *Decl,
+                                        SemanticInfo &ActiveSemantic) {
+  const llvm::StructType *ST = cast<StructType>(Type);
+  const clang::RecordDecl *RD = Decl->getType()->getAsRecordDecl();
+
+  assert(std::distance(RD->field_begin(), RD->field_end()) ==
+         ST->getNumElements());
+
+  if (!ActiveSemantic.Semantic) {
+    ActiveSemantic.Semantic = Decl->getAttr<HLSLSemanticAttr>();
+    ActiveSemantic.Index = ActiveSemantic.Semantic
+                               ? ActiveSemantic.Semantic->getSemanticIndex()
+                               : 0;
+  }
+
+  llvm::Value *Aggregate = llvm::PoisonValue::get(Type);
+  auto FieldDecl = RD->field_begin();
+  for (unsigned I = 0; I < ST->getNumElements(); ++I) {
+    SemanticInfo Info = ActiveSemantic;
+    llvm::Value *ChildValue =
+        handleSemanticLoad(B, ST->getElementType(I), *FieldDecl, Info);
+    if (!ChildValue) {
+      CGM.getDiags().Report(Decl->getInnerLocStart(),
+                            diag::note_hlsl_semantic_used_here)
+          << Decl;
+      return nullptr;
+    }
+    if (ActiveSemantic.Semantic)
+      ActiveSemantic = Info;
+
+    Aggregate = B.CreateInsertValue(Aggregate, ChildValue, I);
+    ++FieldDecl;
+  }
+
+  return Aggregate;
+}
+
 llvm::Value *
 CGHLSLRuntime::handleSemanticLoad(IRBuilder<> &B, llvm::Type *Type,
                                   const clang::DeclaratorDecl *Decl,
                                   SemanticInfo &ActiveSemantic) {
-  assert(!Type->isStructTy());
+  if (Type->isStructTy())
+    return handleStructSemanticLoad(B, Type, Decl, ActiveSemantic);
   return handleScalarSemanticLoad(B, Type, Decl, ActiveSemantic);
 }
 
@@ -671,8 +711,26 @@ void CGHLSLRuntime::emitEntryFunction(const FunctionDecl *FD,
     }
 
     const ParmVarDecl *PD = FD->getParamDecl(Param.getArgNo() - SRetOffset);
-    SemanticInfo ActiveSemantic = {nullptr, 0};
-    Args.push_back(handleSemanticLoad(B, Param.getType(), PD, ActiveSemantic));
+    llvm::Value *SemanticValue = nullptr;
+    if ([[maybe_unused]] HLSLParamModifierAttr *MA =
+            PD->getAttr<HLSLParamModifierAttr>()) {
+      llvm_unreachable("Not handled yet");
+    } else {
+      llvm::Type *ParamType =
+          Param.hasByValAttr() ? Param.getParamByValType() : Param.getType();
+      SemanticInfo ActiveSemantic = {nullptr, 0};
+      SemanticValue = handleSemanticLoad(B, ParamType, PD, ActiveSemantic);
+      if (!SemanticValue)
+        return;
+      if (Param.hasByValAttr()) {
+        llvm::Value *Var = B.CreateAlloca(Param.getParamByValType());
+        B.CreateStore(SemanticValue, Var);
+        SemanticValue = Var;
+      }
+    }
+
+    assert(SemanticValue);
+    Args.push_back(SemanticValue);
   }
 
   CallInst *CI = B.CreateCall(FunctionCallee(Fn), Args, OB);

clang/lib/CodeGen/CGHLSLRuntime.h

@@ -156,6 +156,10 @@ class CGHLSLRuntime {
                                         const clang::DeclaratorDecl *Decl,
                                         SemanticInfo &ActiveSemantic);
 
+  llvm::Value *handleStructSemanticLoad(llvm::IRBuilder<> &B, llvm::Type *Type,
+                                        const clang::DeclaratorDecl *Decl,
+                                        SemanticInfo &ActiveSemantic);
+
   llvm::Value *handleSemanticLoad(llvm::IRBuilder<> &B, llvm::Type *Type,
                                   const clang::DeclaratorDecl *Decl,
                                   SemanticInfo &ActiveSemantic);

clang/test/CodeGenHLSL/semantics/semantic-struct-1.hlsl

@@ -0,0 +1,23 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -x hlsl -emit-llvm -finclude-default-header -disable-llvm-passes -o - %s | FileCheck %s --check-prefixes=CHECK,CHECK-DXIL -DTARGET=dx
+// RUN: %clang_cc1 -triple spirv-linux-vulkan-library -x hlsl -emit-llvm -finclude-default-header -disable-llvm-passes -o - %s | FileCheck %s --check-prefixes=CHECK,CHECK-SPIRV -DTARGET=spv
+
+
+struct Input {
+  uint Idx : SV_DispatchThreadID;
+
+};
+
+// Make sure SV_DispatchThreadID translated into dx.thread.id.
+
+// CHECK:       define void @foo()
+// CHECK-DXIL:  %[[#ID:]] = call i32 @llvm.[[TARGET]].thread.id(i32 0)
+// CHECK-SPIRV: %[[#ID:]] = call i32 @llvm.[[TARGET]].thread.id.i32(i32 0)
+// CHECK:      %[[#TMP:]] = insertvalue %struct.Input poison, i32 %[[#ID]], 0
+// CHECK:      %[[#VAR:]] = alloca %struct.Input, align 8
+// CHECK:                   store %struct.Input %[[#TMP]], ptr %[[#VAR]], align 4
+// CHECK-DXIL:              call void @{{.*}}foo{{.*}}(ptr %[[#VAR]])
+// CHECK-SPIRV:             call spir_func void @{{.*}}foo{{.*}}(ptr %[[#VAR]])
+[shader("compute")]
+[numthreads(8,8,1)]
+void foo(Input input) {}
+

clang/test/CodeGenHLSL/semantics/semantic-struct-2.hlsl

@@ -0,0 +1,25 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -x hlsl -emit-llvm -finclude-default-header -disable-llvm-passes -o - %s | FileCheck %s --check-prefixes=CHECK,CHECK-DXIL -DTARGET=dx
+// RUN: %clang_cc1 -triple spirv-linux-vulkan-library -x hlsl -emit-llvm -finclude-default-header -disable-llvm-passes -o - %s | FileCheck %s --check-prefixes=CHECK,CHECK-SPIRV -DTARGET=spv
+
+
+struct Input {
+  uint Idx : SV_DispatchThreadID;
+  uint Gid : SV_GroupID;
+};
+
+// Make sure SV_DispatchThreadID translated into dx.thread.id.
+
+// CHECK:       define void @foo()
+// CHECK-DXIL:  %[[#ID:]] = call i32 @llvm.[[TARGET]].thread.id(i32 0)
+// CHECK-SPIRV: %[[#ID:]] = call i32 @llvm.[[TARGET]].thread.id.i32(i32 0)
+// CHECK:     %[[#TMP1:]] = insertvalue %struct.Input poison, i32 %[[#ID]], 0
+// CHECK-DXIL: %[[#GID:]] = call i32 @llvm.[[TARGET]].group.id(i32 0)
+// CHECK-SPIRV:%[[#GID:]] = call i32 @llvm.[[TARGET]].group.id.i32(i32 0)
+// CHECK:     %[[#TMP2:]] = insertvalue %struct.Input %[[#TMP1]], i32 %[[#GID]], 1
+// CHECK:      %[[#VAR:]] = alloca %struct.Input, align 8
+// CHECK:                   store %struct.Input %[[#TMP2]], ptr %[[#VAR]], align 4
+// CHECK-DXIL:              call void @{{.*}}foo{{.*}}(ptr %[[#VAR]])
+// CHECK-SPIRV:             call spir_func void @{{.*}}foo{{.*}}(ptr %[[#VAR]])
+[shader("compute")]
+[numthreads(8,8,1)]
+void foo(Input input) {}

clang/test/CodeGenHLSL/semantics/semantic-struct-nested-inherit.hlsl

@@ -0,0 +1,30 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -x hlsl -emit-llvm -finclude-default-header -disable-llvm-passes -o - %s | FileCheck %s --check-prefixes=CHECK,CHECK-DXIL -DTARGET=dx
+// RUN: %clang_cc1 -triple spirv-linux-vulkan-library -x hlsl -emit-llvm -finclude-default-header -disable-llvm-passes -o - %s | FileCheck %s --check-prefixes=CHECK,CHECK-SPIRV -DTARGET=spv
+
+
+struct Inner {
+  uint Gid;
+};
+
+struct Input {
+  uint Idx : SV_DispatchThreadID;
+  Inner inner : SV_GroupIndex;
+};
+
+// Make sure SV_DispatchThreadID translated into dx.thread.id.
+
+// CHECK:       define void @foo()
+// CHECK-DXIL:  %[[#ID:]] = call i32 @llvm.[[TARGET]].thread.id(i32 0)
+// CHECK-SPIRV: %[[#ID:]] = call i32 @llvm.[[TARGET]].thread.id.i32(i32 0)
+// CHECK:     %[[#TMP1:]] = insertvalue %struct.Input poison, i32 %[[#ID]], 0
+// CHECK-DXIL: %[[#GID:]] = call i32 @llvm.dx.flattened.thread.id.in.group()
+// CHECK-SPIRV:%[[#GID:]] = call i32 @llvm.spv.flattened.thread.id.in.group()
+// CHECK:     %[[#TMP2:]] = insertvalue %struct.Inner poison, i32 %[[#GID]], 0
+// CHECK:     %[[#TMP3:]] = insertvalue %struct.Input %[[#TMP1]], %struct.Inner %[[#TMP2]], 1
+// CHECK:      %[[#VAR:]] = alloca %struct.Input, align 8
+// CHECK:                   store %struct.Input %[[#TMP3]], ptr %[[#VAR]], align 4
+// CHECK-DXIL:              call void @{{.*}}foo{{.*}}(ptr %[[#VAR]])
+// CHECK-SPIRV:             call spir_func void @{{.*}}foo{{.*}}(ptr %[[#VAR]])
+[shader("compute")]
+[numthreads(8,8,1)]
+void foo(Input input) {}

clang/test/CodeGenHLSL/semantics/semantic-struct-nested-shadow.hlsl

@@ -0,0 +1,30 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -x hlsl -emit-llvm -finclude-default-header -disable-llvm-passes -o - %s | FileCheck %s --check-prefixes=CHECK,CHECK-DXIL -DTARGET=dx
+// RUN: %clang_cc1 -triple spirv-linux-vulkan-library -x hlsl -emit-llvm -finclude-default-header -disable-llvm-passes -o - %s | FileCheck %s --check-prefixes=CHECK,CHECK-SPIRV -DTARGET=spv
+
+
+struct Inner {
+  uint Gid : SV_GroupID;
+};
+
+struct Input {
+  uint Idx : SV_DispatchThreadID;
+  Inner inner : SV_GroupIndex;
+};
+
+// Make sure SV_DispatchThreadID translated into dx.thread.id.
+
+// CHECK:       define void @foo()
+// CHECK-DXIL:  %[[#ID:]] = call i32 @llvm.[[TARGET]].thread.id(i32 0)
+// CHECK-SPIRV: %[[#ID:]] = call i32 @llvm.[[TARGET]].thread.id.i32(i32 0)
+// CHECK:     %[[#TMP1:]] = insertvalue %struct.Input poison, i32 %[[#ID]], 0
+// CHECK-DXIL: %[[#GID:]] = call i32 @llvm.dx.flattened.thread.id.in.group()
+// CHECK-SPIRV:%[[#GID:]] = call i32 @llvm.spv.flattened.thread.id.in.group()
+// CHECK:     %[[#TMP2:]] = insertvalue %struct.Inner poison, i32 %[[#GID]], 0
+// CHECK:     %[[#TMP3:]] = insertvalue %struct.Input %[[#TMP1]], %struct.Inner %[[#TMP2]], 1
+// CHECK:      %[[#VAR:]] = alloca %struct.Input, align 8
+// CHECK:                   store %struct.Input %[[#TMP3]], ptr %[[#VAR]], align 4
+// CHECK-DXIL:              call void @{{.*}}foo{{.*}}(ptr %[[#VAR]])
+// CHECK-SPIRV:             call spir_func void @{{.*}}foo{{.*}}(ptr %[[#VAR]])
+[shader("compute")]
+[numthreads(8,8,1)]
+void foo(Input input) {}

clang/test/CodeGenHLSL/semantics/semantic-struct-nested.hlsl

@@ -0,0 +1,30 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -x hlsl -emit-llvm -finclude-default-header -disable-llvm-passes -o - %s | FileCheck %s --check-prefixes=CHECK,CHECK-DXIL -DTARGET=dx
+// RUN: %clang_cc1 -triple spirv-linux-vulkan-library -x hlsl -emit-llvm -finclude-default-header -disable-llvm-passes -o - %s | FileCheck %s --check-prefixes=CHECK,CHECK-SPIRV -DTARGET=spv
+
+
+struct Inner {
+  uint Gid : SV_GroupID;
+};
+
+struct Input {
+  uint Idx : SV_DispatchThreadID;
+  Inner inner;
+};
+
+// Make sure SV_DispatchThreadID translated into dx.thread.id.
+
+// CHECK:       define void @foo()
+// CHECK-DXIL:  %[[#ID:]] = call i32 @llvm.[[TARGET]].thread.id(i32 0)
+// CHECK-SPIRV: %[[#ID:]] = call i32 @llvm.[[TARGET]].thread.id.i32(i32 0)
+// CHECK:     %[[#TMP1:]] = insertvalue %struct.Input poison, i32 %[[#ID]], 0
+// CHECK-DXIL: %[[#GID:]] = call i32 @llvm.[[TARGET]].group.id(i32 0)
+// CHECK-SPIRV:%[[#GID:]] = call i32 @llvm.[[TARGET]].group.id.i32(i32 0)
+// CHECK:     %[[#TMP2:]] = insertvalue %struct.Inner poison, i32 %[[#GID]], 0
+// CHECK:     %[[#TMP3:]] = insertvalue %struct.Input %[[#TMP1]], %struct.Inner %[[#TMP2]], 1
+// CHECK:      %[[#VAR:]] = alloca %struct.Input, align 8
+// CHECK:                   store %struct.Input %[[#TMP3]], ptr %[[#VAR]], align 4
+// CHECK-DXIL:              call void @{{.*}}foo{{.*}}(ptr %[[#VAR]])
+// CHECK-SPIRV:             call spir_func void @{{.*}}foo{{.*}}(ptr %[[#VAR]])
+[shader("compute")]
+[numthreads(8,8,1)]
+void foo(Input input) {}