[HLSL] Fix placement of const for resource operator[] (llvm#116698)

We had an incorrect AST here - We want `const T &`, not `T &const`.

Author: bogner

clang/lib/Sema/HLSLExternalSemaSource.cpp

@@ -212,11 +212,11 @@ struct BuiltinTypeDeclBuilder {
 
     // Subscript operators return references to elements, const makes the
     // reference and method const so that the underlying data is not mutable.
-    ReturnTy = AST.getLValueReferenceType(ReturnTy);
     if (IsConst) {
       ExtInfo.TypeQuals.addConst();
       ReturnTy.addConst();
     }
+    ReturnTy = AST.getLValueReferenceType(ReturnTy);
 
     QualType MethodTy =
         AST.getFunctionType(ReturnTy, {AST.UnsignedIntTy}, ExtInfo);

clang/test/AST/HLSL/AppendStructuredBuffer-AST.hlsl

@@ -36,7 +36,7 @@ AppendStructuredBuffer<int> Buffer;
 // CHECK-SAME{LITERAL}: [[hlsl::contained_type(element_type)]]
 // CHECK-NEXT: HLSLResourceAttr 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> Implicit RawBuffer
 
-// CHECK-NOT: CXXMethodDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> operator[] 'element_type &const (unsigned int) const'
+// CHECK-NOT: CXXMethodDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> operator[] 'const element_type &(unsigned int) const'
 // CHECK-NOT: CXXMethodDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> operator[] 'element_type &(unsigned int)'
 
 // CHECK: ClassTemplateSpecializationDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> class AppendStructuredBuffer definition

clang/test/AST/HLSL/ConsumeStructuredBuffer-AST.hlsl

@@ -36,7 +36,7 @@ ConsumeStructuredBuffer<int> Buffer;
 // CHECK-SAME{LITERAL}: [[hlsl::contained_type(element_type)]]
 // CHECK-NEXT: HLSLResourceAttr 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> Implicit RawBuffer
 
-// CHECK-NOT: CXXMethodDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> operator[] 'element_type &const (unsigned int) const'
+// CHECK-NOT: CXXMethodDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> operator[] 'const element_type &(unsigned int) const'
 // CHECK-NOT: CXXMethodDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> operator[] 'element_type &(unsigned int)'
 
 // CHECK: ClassTemplateSpecializationDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> class ConsumeStructuredBuffer definition

clang/test/AST/HLSL/RWBuffer-AST.hlsl

@@ -34,7 +34,7 @@ RWBuffer<float> Buffer;
 // CHECK-SAME{LITERAL}: [[hlsl::contained_type(element_type)]]
 // CHECK-NEXT: HLSLResourceAttr 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> Implicit TypedBuffer
 
-// CHECK: CXXMethodDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> operator[] 'element_type &const (unsigned int) const'
+// CHECK: CXXMethodDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> operator[] 'const element_type &(unsigned int) const'
 // CHECK-NEXT: ParmVarDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> Idx 'unsigned int'
 // CHECK-NEXT: CompoundStmt 0x{{[0-9A-Fa-f]+}} <<invalid sloc>>
 // CHECK-NEXT: ReturnStmt 0x{{[0-9A-Fa-f]+}} <<invalid sloc>>

clang/test/AST/HLSL/RWStructuredBuffer-AST.hlsl

@@ -36,7 +36,7 @@ RWStructuredBuffer<int> Buffer;
 // CHECK-SAME{LITERAL}: [[hlsl::contained_type(element_type)]]
 // CHECK-NEXT: HLSLResourceAttr 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> Implicit RawBuffer
 
-// CHECK: CXXMethodDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> operator[] 'element_type &const (unsigned int) const'
+// CHECK: CXXMethodDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> operator[] 'const element_type &(unsigned int) const'
 // CHECK-NEXT: ParmVarDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> Idx 'unsigned int'
 // CHECK-NEXT: CompoundStmt 0x{{[0-9A-Fa-f]+}} <<invalid sloc>>
 // CHECK-NEXT: ReturnStmt 0x{{[0-9A-Fa-f]+}} <<invalid sloc>>

clang/test/AST/HLSL/RasterizerOrderedStructuredBuffer-AST.hlsl

@@ -37,7 +37,7 @@ RasterizerOrderedStructuredBuffer<int> Buffer;
 // CHECK-SAME{LITERAL}: [[hlsl::contained_type(element_type)]]
 // CHECK-NEXT: HLSLResourceAttr 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> Implicit RawBuffer
 
-// CHECK: CXXMethodDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> operator[] 'element_type &const (unsigned int) const'
+// CHECK: CXXMethodDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> operator[] 'const element_type &(unsigned int) const'
 // CHECK-NEXT: ParmVarDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> Idx 'unsigned int'
 // CHECK-NEXT: CompoundStmt 0x{{[0-9A-Fa-f]+}} <<invalid sloc>>
 // CHECK-NEXT: ReturnStmt 0x{{[0-9A-Fa-f]+}} <<invalid sloc>>

clang/test/AST/HLSL/StructuredBuffer-AST.hlsl

@@ -36,7 +36,7 @@ StructuredBuffer<float> Buffer;
 // CHECK-SAME{LITERAL}: [[hlsl::contained_type(element_type)]]
 // CHECK-NEXT: HLSLResourceAttr 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> Implicit RawBuffer
 
-// CHECK: CXXMethodDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> operator[] 'element_type &const (unsigned int) const'
+// CHECK: CXXMethodDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> operator[] 'const element_type &(unsigned int) const'
 // CHECK-NEXT: ParmVarDecl 0x{{[0-9A-Fa-f]+}} <<invalid sloc>> <invalid sloc> Idx 'unsigned int'
 // CHECK-NEXT: CompoundStmt 0x{{[0-9A-Fa-f]+}} <<invalid sloc>>
 // CHECK-NEXT: ReturnStmt 0x{{[0-9A-Fa-f]+}} <<invalid sloc>>