From 7b09222a9792d9e83c68acea3429e6bd1622e0b8 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Nathan=20Gau=C3=ABr?= Date: Tue, 12 Aug 2025 18:06:17 +0200 Subject: [PATCH 1/2] [HLSL] Add support for input semantics in structs This commit adds the support for semantics annotations on structs, but only for inputs. Due to the current semantics implemented, we cannot test much more than nesting/shadowing. Once user semantics are implemented, we'll be able to test arrays in structs and more complex cases. As-is, this commit has one weakness vs DXC: semantics type validation is not looking at the inner-most type, but the outermost type: ```hlsl struct Inner { uint tid; }; Inner inner : SV_GroupID ``` This sample would fail today because `SV_GroupID` require the type to be an integer. This works in DXC as the inner type is a integer. Because GroupIndex is not correctly validated, I uses this semantic to test the inheritance/shadowing. But this will need to be fixed in a later commit. Requires #152537 --- .../clang/Basic/DiagnosticFrontendKinds.td | 2 + clang/lib/CodeGen/CGHLSLRuntime.cpp | 63 ++++++++++++++++++- clang/lib/CodeGen/CGHLSLRuntime.h | 4 ++ .../semantics/semantic-struct-1.hlsl | 23 +++++++ .../semantics/semantic-struct-2.hlsl | 25 ++++++++ .../semantic-struct-nested-inherit.hlsl | 30 +++++++++ .../semantic-struct-nested-shadow.hlsl | 30 +++++++++ .../semantics/semantic-struct-nested.hlsl | 30 +++++++++ 8 files changed, 204 insertions(+), 3 deletions(-) create mode 100644 clang/test/CodeGenHLSL/semantics/semantic-struct-1.hlsl create mode 100644 clang/test/CodeGenHLSL/semantics/semantic-struct-2.hlsl create mode 100644 clang/test/CodeGenHLSL/semantics/semantic-struct-nested-inherit.hlsl create mode 100644 clang/test/CodeGenHLSL/semantics/semantic-struct-nested-shadow.hlsl create mode 100644 clang/test/CodeGenHLSL/semantics/semantic-struct-nested.hlsl diff --git a/clang/include/clang/Basic/DiagnosticFrontendKinds.td b/clang/include/clang/Basic/DiagnosticFrontendKinds.td index 2fd2ae434d7c5..6c5a92c63d25a 100644 --- a/clang/include/clang/Basic/DiagnosticFrontendKinds.td +++ b/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; diff --git a/clang/lib/CodeGen/CGHLSLRuntime.cpp b/clang/lib/CodeGen/CGHLSLRuntime.cpp index 60ad3eb75afea..f17e9b1d908e9 100644 --- a/clang/lib/CodeGen/CGHLSLRuntime.cpp +++ b/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(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(); + 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 +711,25 @@ 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 (HLSLParamModifierAttr *MA = PD->getAttr()) { + 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); diff --git a/clang/lib/CodeGen/CGHLSLRuntime.h b/clang/lib/CodeGen/CGHLSLRuntime.h index 25d4c65426b0d..5d28994a5277b 100644 --- a/clang/lib/CodeGen/CGHLSLRuntime.h +++ b/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); diff --git a/clang/test/CodeGenHLSL/semantics/semantic-struct-1.hlsl b/clang/test/CodeGenHLSL/semantics/semantic-struct-1.hlsl new file mode 100644 index 0000000000000..ddd0baed41f37 --- /dev/null +++ b/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) {} + diff --git a/clang/test/CodeGenHLSL/semantics/semantic-struct-2.hlsl b/clang/test/CodeGenHLSL/semantics/semantic-struct-2.hlsl new file mode 100644 index 0000000000000..0d9c91e746454 --- /dev/null +++ b/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) {} diff --git a/clang/test/CodeGenHLSL/semantics/semantic-struct-nested-inherit.hlsl b/clang/test/CodeGenHLSL/semantics/semantic-struct-nested-inherit.hlsl new file mode 100644 index 0000000000000..f4c4d86933ca1 --- /dev/null +++ b/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) {} diff --git a/clang/test/CodeGenHLSL/semantics/semantic-struct-nested-shadow.hlsl b/clang/test/CodeGenHLSL/semantics/semantic-struct-nested-shadow.hlsl new file mode 100644 index 0000000000000..e1344dd87a6ed --- /dev/null +++ b/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) {} diff --git a/clang/test/CodeGenHLSL/semantics/semantic-struct-nested.hlsl b/clang/test/CodeGenHLSL/semantics/semantic-struct-nested.hlsl new file mode 100644 index 0000000000000..cd6f9460bc617 --- /dev/null +++ b/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) {} From d4d26faeca220f4d3530916d5dd53e4fbc882501 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Nathan=20Gau=C3=ABr?= Date: Tue, 9 Sep 2025 16:11:13 +0200 Subject: [PATCH 2/2] add maybe_unused on fixme location --- clang/lib/CodeGen/CGHLSLRuntime.cpp | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/clang/lib/CodeGen/CGHLSLRuntime.cpp b/clang/lib/CodeGen/CGHLSLRuntime.cpp index f17e9b1d908e9..15863e8e28dfc 100644 --- a/clang/lib/CodeGen/CGHLSLRuntime.cpp +++ b/clang/lib/CodeGen/CGHLSLRuntime.cpp @@ -712,7 +712,8 @@ void CGHLSLRuntime::emitEntryFunction(const FunctionDecl *FD, const ParmVarDecl *PD = FD->getParamDecl(Param.getArgNo() - SRetOffset); llvm::Value *SemanticValue = nullptr; - if (HLSLParamModifierAttr *MA = PD->getAttr()) { + if ([[maybe_unused]] HLSLParamModifierAttr *MA = + PD->getAttr()) { llvm_unreachable("Not handled yet"); } else { llvm::Type *ParamType =