[HLSL] Add handle initialization for simple resource declarations

clang/include/clang/AST/Type.h

@@ -6320,6 +6320,10 @@ class HLSLAttributedResourceType : public Type, public llvm::FoldingSetNode {
   static bool classof(const Type *T) {
     return T->getTypeClass() == HLSLAttributedResource;
   }
+
+  // Returns handle type from HLSL resource, if the type is a resource
+  static const HLSLAttributedResourceType *
+  findHandleTypeOnResource(const Type *RT);
 };
 
 class TemplateTypeParmType : public Type, public llvm::FoldingSetNode {

clang/lib/AST/Type.cpp

@@ -5334,3 +5334,18 @@ std::string FunctionEffectWithCondition::description() const {
     Result += "(expr)";
   return Result;
 }
+
+const HLSLAttributedResourceType *
+HLSLAttributedResourceType::findHandleTypeOnResource(const Type *RT) {
+  // If the type T is an HLSL resource class, the first field must
+  // be the resource handle of type HLSLAttributedResourceType
+  const clang::Type *Ty = RT->getUnqualifiedDesugaredType();
+  if (const RecordDecl *RD = Ty->getAsCXXRecordDecl()) {
+    if (!RD->fields().empty()) {
+      const auto &FirstFD = RD->fields().begin();
+      return dyn_cast<HLSLAttributedResourceType>(
+          FirstFD->getType().getTypePtr());
+    }
+  }
+  return nullptr;
+}

clang/lib/CodeGen/CGDeclCXX.cpp

@@ -1121,6 +1121,14 @@ CodeGenFunction::GenerateCXXGlobalInitFunc(llvm::Function *Fn,
       if (Decls[i])
         EmitRuntimeCall(Decls[i]);
 
+    if (getLangOpts().HLSL) {
+      CGHLSLRuntime &CGHLSL = CGM.getHLSLRuntime();
+      if (CGHLSL.needsResourceBindingInitFn()) {
+        llvm::Function *ResInitFn = CGHLSL.createResourceBindingInitFn();
+        Builder.CreateCall(llvm::FunctionCallee(ResInitFn), {});
+      }
+    }
+
     Scope.ForceCleanup();
 
     if (ExitBlock) {

clang/lib/CodeGen/CGHLSLRuntime.cpp

@@ -18,8 +18,13 @@
 #include "TargetInfo.h"
 #include "clang/AST/Decl.h"
 #include "clang/Basic/TargetOptions.h"
+#include "llvm/IR/GlobalVariable.h"
+#include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Metadata.h"
 #include "llvm/IR/Module.h"
+#include "llvm/IR/Value.h"
+#include "llvm/Support/Alignment.h"
+
 #include "llvm/Support/FormatVariadic.h"
 
 using namespace clang;
@@ -489,3 +494,92 @@ void CGHLSLRuntime::generateGlobalCtorDtorCalls() {
       GV->eraseFromParent();
   }
 }
+
+// Returns handle type from a resource, if the type is a resource
+static const HLSLAttributedResourceType *
+findHandleTypeOnResource(const clang::Type *Ty) {
+  return HLSLAttributedResourceType::findHandleTypeOnResource(Ty);
+}
+
+void CGHLSLRuntime::handleGlobalVarDefinition(const VarDecl *VD,
+                                              llvm::GlobalVariable *GV) {
+  // If the global variable has resource binding, add it to the list of globals
+  // that need resource binding initialization.
+  const HLSLResourceBindingAttr *RBA = VD->getAttr<HLSLResourceBindingAttr>();
+  if (!RBA)
+    return;
+
+  if (!findHandleTypeOnResource(VD->getType().getTypePtr()))
+    // FIXME: Only simple declarations of resources are supported for now.
+    // Arrays of resources or resources in user defined classes are
+    // not implemented yet.
+    return;
+
+  ResourcesToBind.emplace_back(VD, GV);
+}
+
+bool CGHLSLRuntime::needsResourceBindingInitFn() {
+  return !ResourcesToBind.empty();
+}
+
+llvm::Function *CGHLSLRuntime::createResourceBindingInitFn() {
+  // No resources to bind
+  assert(needsResourceBindingInitFn() && "no resources to bind");
+
+  LLVMContext &Ctx = CGM.getLLVMContext();
+  llvm::Type *Int1Ty = llvm::Type::getInt1Ty(Ctx);
+
+  llvm::Function *InitResBindingsFunc =
+      llvm::Function::Create(llvm::FunctionType::get(CGM.VoidTy, false),
+                             llvm::GlobalValue::InternalLinkage,
+                             "_init_resource_bindings", CGM.getModule());
+
+  llvm::BasicBlock *EntryBB =
+      llvm::BasicBlock::Create(Ctx, "entry", InitResBindingsFunc);
+  CGBuilderTy Builder(CGM, Ctx);
+  const DataLayout &DL = CGM.getModule().getDataLayout();
+  Builder.SetInsertPoint(EntryBB);
+
+  for (const auto &[VD, GV] : ResourcesToBind) {
+    for (Attr *A : VD->getAttrs()) {
+      HLSLResourceBindingAttr *RBA = dyn_cast<HLSLResourceBindingAttr>(A);
+      if (!RBA)
+        continue;
+
+      const HLSLAttributedResourceType *AttrResType =
+          findHandleTypeOnResource(VD->getType().getTypePtr());
+
+      // FIXME: Only simple declarations of resources are supported for now.
+      // Arrays of resources or resources in user defined classes are
+      // not implemented yet.
+      assert(AttrResType != nullptr &&
+             "Resource class must have a handle of HLSLAttributedResourceType");
+
+      llvm::Type *TargetTy =
+          CGM.getTargetCodeGenInfo().getHLSLType(CGM, AttrResType);
+      assert(TargetTy != nullptr &&
+             "Failed to convert resource handle to target type");
+
+      auto *Space = llvm::ConstantInt::get(CGM.IntTy, RBA->getSpaceNumber());
+      auto *Slot = llvm::ConstantInt::get(CGM.IntTy, RBA->getSlotNumber());
+      // FIXME: resource arrays are not yet implemented
+      auto *Range = llvm::ConstantInt::get(CGM.IntTy, 1);
+      auto *Index = llvm::ConstantInt::get(CGM.IntTy, 0);
+      // FIXME: NonUniformResourceIndex bit is not yet implemented
+      auto *NonUniform = llvm::ConstantInt::get(Int1Ty, false);
+      llvm::Value *Args[] = {Space, Slot, Range, Index, NonUniform};
+
+      llvm::Value *CreateHandle = Builder.CreateIntrinsic(
+          /*ReturnType=*/TargetTy, getCreateHandleFromBindingIntrinsic(), Args,
+          nullptr, Twine(VD->getName()).concat("_h"));
+
+      llvm::Value *HandleRef =
+          Builder.CreateStructGEP(GV->getValueType(), GV, 0);
+      Builder.CreateAlignedStore(CreateHandle, HandleRef,
+                                 HandleRef->getPointerAlignment(DL));
+    }
+  }
+
+  Builder.CreateRetVoid();
+  return InitResBindingsFunc;
+}

clang/lib/CodeGen/CGHLSLRuntime.h

@@ -92,6 +92,8 @@ class CGHLSLRuntime {
   GENERATE_HLSL_INTRINSIC_FUNCTION(WaveIsFirstLane, wave_is_first_lane)
   GENERATE_HLSL_INTRINSIC_FUNCTION(WaveReadLaneAt, wave_readlane)
 
+  GENERATE_HLSL_INTRINSIC_FUNCTION(CreateHandleFromBinding, handle_fromBinding)
+
   //===----------------------------------------------------------------------===//
   // End of reserved area for HLSL intrinsic getters.
   //===----------------------------------------------------------------------===//
@@ -137,6 +139,10 @@ class CGHLSLRuntime {
 
   void emitEntryFunction(const FunctionDecl *FD, llvm::Function *Fn);
   void setHLSLFunctionAttributes(const FunctionDecl *FD, llvm::Function *Fn);
+  void handleGlobalVarDefinition(const VarDecl *VD, llvm::GlobalVariable *Var);
+
+  bool needsResourceBindingInitFn();
+  llvm::Function *createResourceBindingInitFn();
 
 private:
   void addBufferResourceAnnotation(llvm::GlobalVariable *GV,
@@ -148,6 +154,9 @@ class CGHLSLRuntime {
   void addBufferDecls(const DeclContext *DC, Buffer &CB);
   llvm::Triple::ArchType getArch();
   llvm::SmallVector<Buffer> Buffers;
+
+  llvm::SmallVector<std::pair<const VarDecl *, llvm::GlobalVariable *>>
+      ResourcesToBind;
 };
 
 } // namespace CodeGen

clang/lib/CodeGen/CodeGenModule.cpp

@@ -5634,6 +5634,9 @@ void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D,
     getCUDARuntime().handleVarRegistration(D, *GV);
   }
 
+  if (LangOpts.HLSL)
+    getHLSLRuntime().handleGlobalVarDefinition(D, GV);
+
   GV->setInitializer(Init);
   if (emitter)
     emitter->finalize(GV);

clang/lib/Sema/SemaHLSL.cpp

@@ -1050,16 +1050,7 @@ SemaHLSL::TakeLocForHLSLAttribute(const HLSLAttributedResourceType *RT) {
 // Returns handle type of a resource, if the type is a resource
 static const HLSLAttributedResourceType *
 findHandleTypeOnResource(const Type *Ty) {
-  // If Ty is a resource class, the first field must
-  // be the resource handle of type HLSLAttributedResourceType
-  if (RecordDecl *RD = Ty->getAsCXXRecordDecl()) {
-    if (!RD->fields().empty()) {
-      const auto &FirstFD = RD->fields().begin();
-      return dyn_cast<HLSLAttributedResourceType>(
-          FirstFD->getType().getTypePtr());
-    }
-  }
-  return nullptr;
+  return HLSLAttributedResourceType::findHandleTypeOnResource(Ty);
 }
 
 // Walks though the global variable declaration, collects all resource binding

clang/test/CodeGenHLSL/builtins/RWBuffer-constructor.hlsl

@@ -1,19 +1,22 @@
-// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -x hlsl -emit-llvm -disable-llvm-passes -o - %s | FileCheck %s
-// RUN: %clang_cc1 -triple spirv-vulkan-library -x hlsl -emit-llvm -disable-llvm-passes -o - %s | FileCheck %s --check-prefix=CHECK-SPIRV
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -x hlsl -emit-llvm -disable-llvm-passes -o - %s | FileCheck %s --check-prefixes=CHECK,CHECK-DXIL
+// FIXME: SPIR-V codegen of llvm.spv.handle.fromBinding is not yet implemented
+// RUN-DISABLED: %clang_cc1 -triple spirv-vulkan-library -x hlsl -emit-llvm -disable-llvm-passes -o - %s | FileCheck %s --check-prefixes=CHECK,CHECK-SPIRV
 
-// XFAIL: *
-// This expectedly fails because create.handle is no longer called
-// from RWBuffer constructor and the replacement has not been
-// implemented yet. This test should be updated to expect
-// dx.create.handleFromBinding as part of issue #105076.
+// NOTE: SPIRV codegen for resource types is not yet implemented
 
-RWBuffer<float> Buf;
+RWBuffer<float> Buf : register(u5, space3);
 
 // CHECK: define linkonce_odr noundef ptr @"??0?$RWBuffer@M@hlsl@@QAA@XZ"
 // CHECK-NEXT: entry:
 
-// CHECK: %[[HandleRes:[0-9]+]] = call ptr @llvm.dx.create.handle(i8 1)
-// CHECK: store ptr %[[HandleRes]], ptr %h, align 4
+// CHECK: define internal void @_GLOBAL__sub_I_RWBuffer_constructor.hlsl()
+// CHECK-NEXT: entry:
+// CHECK-NEXT: call void @"??__EBuf@@YAXXZ"()
+// CHECK-NEXT: call void @_init_resource_bindings()
 
-// CHECK-SPIRV: %[[HandleRes:[0-9]+]] = call ptr @llvm.spv.create.handle(i8 1)
-// CHECK-SPIRV: store ptr %[[HandleRes]], ptr %h, align 8
+// CHECK: define internal void @_init_resource_bindings() {
+// CHECK-NEXT: entry:
+// CHECK-DXIL-NEXT: %Buf_h = call target("dx.TypedBuffer", float, 1, 0, 0) @llvm.dx.handle.fromBinding.tdx.TypedBuffer_f32_1_0_0t(i32 3, i32 5, i32 1, i32 0, i1 false)
+// CHECK-DXIL-NEXT: store target("dx.TypedBuffer", float, 1, 0, 0) %Buf_h, ptr @"?Buf@@3V?$RWBuffer@M@hlsl@@A", align 4
+// CHECK-SPIRV-NEXT: %Buf_h = call target("dx.TypedBuffer", float, 1, 0, 0) @llvm.spv.handle.fromBinding.tdx.TypedBuffer_f32_1_0_0t(i32 3, i32 5, i32 1, i32 0, i1 false)
+// CHECK-SPIRV-NEXT: store target("dx.TypedBuffer", float, 1, 0, 0) %Buf_h, ptr @"?Buf@@3V?$RWBuffer@M@hlsl@@A", align 4

clang/test/CodeGenHLSL/builtins/StructuredBuffer-constructor.hlsl

@@ -1,19 +1,20 @@
-// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -x hlsl -emit-llvm -disable-llvm-passes -o - %s | FileCheck %s
-// RUN: %clang_cc1 -triple spirv-vulkan-library -x hlsl -emit-llvm -disable-llvm-passes -o - %s | FileCheck %s --check-prefix=CHECK-SPIRV
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -x hlsl -emit-llvm -disable-llvm-passes -o - %s | FileCheck %s --check-prefixes=CHECK,CHECK-DXIL
+// RUN-DISABLED: %clang_cc1 -triple spirv-vulkan-library -x hlsl -emit-llvm -disable-llvm-passes -o - %s | FileCheck %s --check-prefixes=CHECK,CHECK-SPIRV
 
-// XFAIL: *
-// This expectedly fails because create.handle is no longer invoked
-// from StructuredBuffer constructor and the replacement has not been
-// implemented yet. This test should be updated to expect
-// dx.create.handleFromBinding as part of issue #105076.
-
-StructuredBuffer<float> Buf;
+// NOTE: SPIRV codegen for resource types is not yet implemented
+StructuredBuffer<float> Buf : register(u10);
 
 // CHECK: define linkonce_odr noundef ptr @"??0?$StructuredBuffer@M@hlsl@@QAA@XZ"
 // CHECK-NEXT: entry:
 
-// CHECK: %[[HandleRes:[0-9]+]] = call ptr @llvm.dx.create.handle(i8 1)
-// CHECK: store ptr %[[HandleRes]], ptr %h, align 4
+// CHECK: define internal void @_GLOBAL__sub_I_StructuredBuffer_constructor.hlsl()
+// CHECK-NEXT: entry:
+// CHECK-NEXT: call void @"??__EBuf@@YAXXZ"()
+// CHECK-NEXT: call void @_init_resource_bindings()
 
-// CHECK-SPIRV: %[[HandleRes:[0-9]+]] = call ptr @llvm.spv.create.handle(i8 1)
-// CHECK-SPIRV: store ptr %[[HandleRes]], ptr %h, align 8
+// CHECK: define internal void @_init_resource_bindings() {
+// CHECK-NEXT: entry:
+// CHECK-DXIL-NEXT: %Buf_h = call target("dx.RawBuffer", float, 1, 0) @llvm.dx.handle.fromBinding.tdx.RawBuffer_f32_1_0t(i32 0, i32 10, i32 1, i32 0, i1 false)
+// CHECK-DXIL-NEXT: store target("dx.RawBuffer", float, 1, 0) %Buf_h, ptr @"?Buf@@3V?$StructuredBuffer@M@hlsl@@A", align 4
+// CHECK-SPIRV-NEXT: %Buf_h = call target("dx.RawBuffer", float, 1, 0) @llvm.spv.handle.fromBinding.tdx.RawBuffer_f32_1_0t(i32 0, i32 10, i32 1, i32 0, i1 false)
+// CHECK-SPIRV-NEXT: store target("dx.RawBuffer", float, 1, 0) %Buf_h, ptr @"?Buf@@3V?$StructuredBuffer@M@hlsl@@A", align 4