[HLSL] Preserve HLSLVkBindingAttr even if the target is not SPIR-V

The attribute needs to be preserved for rewriter scenarios.
Two places are updated to use the ResourceBindingAttrs helper struct
to make sure the HLSLVkBindingAttr is ignored when the target is DirectX.

Author: hekota

clang/include/clang/AST/HLSLResource.h

@@ -69,6 +69,11 @@ struct ResourceBindingAttrs {
     assert(hasImplicitOrderID());
     return RegBinding->getImplicitBindingOrderID();
   }
+
+  void setImplicitOrderID(unsigned Value) const {
+    assert(hasBinding() && !isExplicit() && !hasImplicitOrderID());
+    RegBinding->setImplicitBindingOrderID(Value);
+  }
 };
 
 } // namespace hlsl

clang/lib/Sema/SemaHLSL.cpp

@@ -598,18 +598,17 @@ void SemaHLSL::ActOnFinishBuffer(Decl *Dcl, SourceLocation RBrace) {
 
   validatePackoffset(SemaRef, BufDecl);
 
-  // create buffer layout struct
   createHostLayoutStructForBuffer(SemaRef, BufDecl);
 
-  HLSLVkBindingAttr *VkBinding = Dcl->getAttr<HLSLVkBindingAttr>();
-  HLSLResourceBindingAttr *RBA = Dcl->getAttr<HLSLResourceBindingAttr>();
-  if (!VkBinding && (!RBA || !RBA->hasRegisterSlot())) {
+  // Handle implicit binding if needed.
+  ResourceBindingAttrs ResourceAttrs(Dcl);
+  if (!ResourceAttrs.isExplicit()) {
     SemaRef.Diag(Dcl->getLocation(), diag::warn_hlsl_implicit_binding);
     // Use HLSLResourceBindingAttr to transfer implicit binding order_ID
     // to codegen. If it does not exist, create an implicit attribute.
     uint32_t OrderID = getNextImplicitBindingOrderID();
-    if (RBA)
-      RBA->setImplicitBindingOrderID(OrderID);
+    if (ResourceAttrs.hasBinding())
+      ResourceAttrs.setImplicitOrderID(OrderID);
     else
       addImplicitBindingAttrToDecl(SemaRef, BufDecl,
                                    BufDecl->isCBuffer() ? RegisterType::CBuffer
@@ -1590,10 +1589,6 @@ void SemaHLSL::handleVkConstantIdAttr(Decl *D, const ParsedAttr &AL) {
 }
 
 void SemaHLSL::handleVkBindingAttr(Decl *D, const ParsedAttr &AL) {
-  // The vk::binding attribute only applies to SPIR-V.
-  if (!getASTContext().getTargetInfo().getTriple().isSPIRV())
-    return;
-
   uint32_t Binding = 0;
   if (!SemaRef.checkUInt32Argument(AL, AL.getArgAsExpr(0), Binding))
     return;
@@ -3786,17 +3781,15 @@ void SemaHLSL::ActOnVariableDeclarator(VarDecl *VD) {
       // If the resource array does not have an explicit binding attribute,
       // create an implicit one. It will be used to transfer implicit binding
       // order_ID to codegen.
-      if (!VD->hasAttr<HLSLVkBindingAttr>()) {
-        HLSLResourceBindingAttr *RBA = VD->getAttr<HLSLResourceBindingAttr>();
-        if (!RBA || !RBA->hasRegisterSlot()) {
-          uint32_t OrderID = getNextImplicitBindingOrderID();
-          if (RBA)
-            RBA->setImplicitBindingOrderID(OrderID);
-          else
-            addImplicitBindingAttrToDecl(
-                SemaRef, VD, getRegisterType(getResourceArrayHandleType(VD)),
-                OrderID);
-        }
+      ResourceBindingAttrs Binding(VD);
+      if (!Binding.isExplicit()) {
+        uint32_t OrderID = getNextImplicitBindingOrderID();
+        if (Binding.hasBinding())
+          Binding.setImplicitOrderID(OrderID);
+        else
+          addImplicitBindingAttrToDecl(
+              SemaRef, VD, getRegisterType(getResourceArrayHandleType(VD)),
+              OrderID);
       }
     }
   }

clang/test/AST/HLSL/resource_binding_attr.hlsl

@@ -92,9 +92,8 @@ cbuffer CB3 {
 StructuredBuffer<float> SB[10];
 
 // CHECK: VarDecl {{.*}} SB2 'StructuredBuffer<float>[10]'
+// CHECK: HLSLVkBindingAttr {{.*}} 2 0
 // DXIL: HLSLResourceBindingAttr {{.*}} Implicit
-// DXIL-NOT: HLSLVkBindingAttr
-// SPV: HLSLVkBindingAttr {{.*}} 2 0
 // SPV-NOT: HLSLResourceBindingAttr {{.*}} Implicit
 [[vk::binding(2)]]
 StructuredBuffer<float> SB2[10];

clang/test/AST/HLSL/vk_binding_attr.hlsl

@@ -10,8 +10,7 @@
 // SPV-NEXT: IntegerLiteral {{.*}} 'unsigned int' 102
 // DXIL-NEXT: IntegerLiteral {{.*}} 'unsigned int' 0
 // DXIL-NEXT: IntegerLiteral {{.*}} 'unsigned int' 0
-// SPV: HLSLVkBindingAttr {{.*}} 23 102
-// DXIL-NOT: HLSLVkBindingAttr
+// CHECK: HLSLVkBindingAttr {{.*}} 23 102
 [[vk::binding(23, 102)]] StructuredBuffer<float> Buf;
 
 // CHECK: VarDecl {{.*}} Buf2 'StructuredBuffer<float>':'hlsl::StructuredBuffer<float>'
@@ -23,8 +22,7 @@
 // SPV-NEXT: IntegerLiteral {{.*}} 'unsigned int' 1
 // DXIL-NEXT: IntegerLiteral {{.*}} 'unsigned int' 23
 // DXIL-NEXT: IntegerLiteral {{.*}} 'unsigned int' 102
-// SPV: HLSLVkBindingAttr {{.*}} 14 1
-// DXIL-NOT: HLSLVkBindingAttr
+// CHECK: HLSLVkBindingAttr {{.*}} 14 1
 // CHECK: HLSLResourceBindingAttr {{.*}} "t23" "space102"
 [[vk::binding(14, 1)]] StructuredBuffer<float> Buf2 : register(t23, space102);
 
@@ -37,15 +35,13 @@
 // SPV-NEXT: IntegerLiteral {{.*}} 'unsigned int' 0
 // DXIL-NEXT: IntegerLiteral {{.*}} 'unsigned int' 23
 // DXIL-NEXT: IntegerLiteral {{.*}} 'unsigned int' 102
-// SPV: HLSLVkBindingAttr {{.*}} 14 0
-// DXIL-NOT: HLSLVkBindingAttr
+// CHECK: HLSLVkBindingAttr {{.*}} 14 0
 // CHECK: HLSLResourceBindingAttr {{.*}} "t23" "space102"
 [[vk::binding(14)]] StructuredBuffer<float> Buf3 : register(t23, space102);
 
 // CHECK: HLSLBufferDecl {{.*}} cbuffer CB
 // CHECK-NEXT: HLSLResourceClassAttr {{.*}} Implicit CBuffer
-// SPV-NEXT: HLSLVkBindingAttr {{.*}} 1 2
-// DXIL-NOT: HLSLVkBindingAttr
+// CHECK: HLSLVkBindingAttr {{.*}} 1 2
 [[vk::binding(1, 2)]] cbuffer CB {
   float a;
 }
@@ -54,15 +50,14 @@
 // CHECK-NEXT: CallExpr {{.*}} 'Buffer<int>':'hlsl::Buffer<int>'
 // CHECK-NEXT: ImplicitCastExpr {{.*}} 'hlsl::Buffer<int> (*)(unsigned int, unsigned int, int, unsigned int, const char *)' <FunctionToPointerDecay>
 // SPV-NEXT: DeclRefExpr {{.*}} 'hlsl::Buffer<int> (unsigned int, unsigned int, int, unsigned int, const char *)' 
-// SPV-NEXT-SAME: CXXMethod {{.*}} '__createFromBinding' 'Buffer<int> (unsigned int, unsigned int, int, unsigned int, const char *)'
+// SPV-NEXT-SAME: CXXMethod {{.*}} '__createFromBinding' 'hlsl::Buffer<int> (unsigned int, unsigned int, int, unsigned int, const char *)'
 // SPV-NEXT: IntegerLiteral {{.*}} 'unsigned int' 24
 // SPV-NEXT: IntegerLiteral {{.*}} 'unsigned int' 103
-// DXIL-NEXT: DeclRefExpr {{.*}} 'hlsl::Buffer<int> (unsigned int, unsigned int, int, unsigned int, const char *)' 
-// DXIL-NEXT-SAME: CXXMethod {{.*}} '__createFromImplicitBinding' 'Buffer<int> (unsigned int, unsigned int, int, unsigned int, const char *)'
+// DXIL-NEXT: DeclRefExpr {{.*}} 'hlsl::Buffer<int> (unsigned int, unsigned int, int, unsigned int, const char *)'
+// DXIL-NEXT-SAME: CXXMethod {{.*}} '__createFromImplicitBinding' 'hlsl::Buffer<int> (unsigned int, unsigned int, int, unsigned int, const char *)'
 // DXIL-NEXT: IntegerLiteral {{.*}} 'unsigned int' 2
 // DXIL-NEXT: IntegerLiteral {{.*}} 'unsigned int' 0
-// SPV: HLSLVkBindingAttr {{.*}} 24 103
-// DXIL-NOT: HLSLVkBindingAttr
+// CHECK: HLSLVkBindingAttr {{.*}} 24 103
 [[vk::binding(24, 103)]] Buffer<int> Buf4;
 
 // CHECK: VarDecl {{.*}} Buf5 'RWBuffer<int2>':'hlsl::RWBuffer<vector<int, 2>>'
@@ -76,8 +71,7 @@
 // DXIL-NEXT-SAME: CXXMethod {{.*}} '__createFromImplicitBinding' 'Buffer<int2> (unsigned int, unsigned int, int, unsigned int, const char *)'
 // DXIL-NEXT: IntegerLiteral {{.*}} 'unsigned int' 3
 // DXIL-NEXT: IntegerLiteral {{.*}} 'unsigned int' 0
-// SPV: HLSLVkBindingAttr {{.*}} 25 104
-// DXIL-NOT: HLSLVkBindingAttr
+// CHECK: HLSLVkBindingAttr {{.*}} 25 104
 [[vk::binding(25, 104)]] RWBuffer<int2> Buf5;
 
 // CHECK: VarDecl {{.*}} Buf6 'RWStructuredBuffer<int>':'hlsl::RWStructuredBuffer<int>'
@@ -91,6 +85,5 @@
 // DXIL-NEXT-SAME: CXXMethod {{.*}} '__createFromBinding' 'hlsl::RWStructuredBuffer<int> (unsigned int, unsigned int, int, unsigned int, const char *)'
 // DXIL-NEXT: IntegerLiteral {{.*}} 'unsigned int' 4
 // DXIL-NEXT: IntegerLiteral {{.*}} 'unsigned int' 0
-// SPV: HLSLVkBindingAttr {{.*}} 26 105
-// DXIL-NOT: HLSLVkBindingAttr
+// CHECK: HLSLVkBindingAttr {{.*}} 26 105
 [[vk::binding(26, 105)]] RWStructuredBuffer<int> Buf6;