[HLSL] Add support for fixed-size global resource arrays

[hekota]

Adds support for fixed-size resource arrays declared at the global scope.

When a global resource array is indexed to access an individual resource, codegen will translate the ArraySubscriptExpr into a constructor call for the specific resource record type and binding.

Related to 145424

[hekota]

Making this a draft for now because it only supports register binding and it will have conflicts with the change that adds [[vk:binding]] attribute (#150957). Once that gets merged, I will update this PR to resolve the conflicts and add [[vk:binding]] support for arrays as well.

@s-perron - is your change ready to get merged?

[s-perron]

I'll see what I can do. I'm on vacation right now. I need to make the change you suggested

[hekota]

I'll see what I can do. I'm on vacation right now. I need to make the change you suggested

If that's the only thing blocking the merge, feel free to go ahead and merge it without my suggested change. I can do the update on my side. I think I need to move that function higher in the file anyway.

[hekota]

@s-perron - when you come back from your vacation - do you have any thoughts on how to update the CodeGenHLSL/convergence/global_array.hlsl? With this change resource arrays are no longer initialized with a loop that calls the default constructor.

The tests has been added in #140120.

[github-actions]

⚠️ C/C++ code formatter, clang-format found issues in your code. ⚠️

You can test this locally with the following command:

git-clang-format --diff HEAD~1 HEAD --extensions cpp,h -- clang/include/clang/AST/Type.h clang/include/clang/Sema/SemaHLSL.h clang/lib/AST/Type.cpp clang/lib/CodeGen/CGExpr.cpp clang/lib/CodeGen/CGHLSLRuntime.cpp clang/lib/CodeGen/CGHLSLRuntime.h clang/lib/CodeGen/CodeGenModule.cpp clang/lib/Sema/SemaHLSL.cpp

View the diff from clang-format here.

diff --git a/clang/lib/CodeGen/CGHLSLRuntime.cpp b/clang/lib/CodeGen/CGHLSLRuntime.cpp
index 8a362cc55..915e967c3 100644
--- a/clang/lib/CodeGen/CGHLSLRuntime.cpp
+++ b/clang/lib/CodeGen/CGHLSLRuntime.cpp
@@ -857,7 +857,8 @@ std::optional<LValue> CGHLSLRuntime::emitResourceArraySubscriptExpr(
   }
 
   // find binding info for the resource array
-  // (for implicit binding an HLSLResourceBindingAttr should have been added by SemaHLSL)
+  // (for implicit binding an HLSLResourceBindingAttr should have been added by
+  // SemaHLSL)
   QualType ResourceTy = ArraySubsExpr->getType();
   HLSLVkBindingAttr *VkBinding = ArrayDecl->getAttr<HLSLVkBindingAttr>();
   HLSLResourceBindingAttr *RBA = ArrayDecl->getAttr<HLSLResourceBindingAttr>();
@@ -865,8 +866,9 @@ std::optional<LValue> CGHLSLRuntime::emitResourceArraySubscriptExpr(
 
   // lookup the resource class constructor based on the resource type and
   // binding
-  CXXConstructorDecl *CD = findResourceConstructorDecl(
-      ArrayDecl->getASTContext(), ResourceTy, VkBinding || RBA->hasRegisterSlot());
+  CXXConstructorDecl *CD =
+      findResourceConstructorDecl(ArrayDecl->getASTContext(), ResourceTy,
+                                  VkBinding || RBA->hasRegisterSlot());
 
   // create a temporary variable for the resource class instance (we need to
   // return an LValue)
diff --git a/clang/lib/Sema/SemaHLSL.cpp b/clang/lib/Sema/SemaHLSL.cpp
index 5bfb8b933..baf30f6a9 100644
--- a/clang/lib/Sema/SemaHLSL.cpp
+++ b/clang/lib/Sema/SemaHLSL.cpp
@@ -3750,9 +3750,9 @@ void SemaHLSL::createResourceRecordCtorArgs(const Type *ResourceTy,
     uint32_t OrderID = (RBA && RBA->hasImplicitBindingOrderID())
                            ? RBA->getImplicitBindingOrderID()
                            : getNextImplicitBindingOrderID();
-    IntegerLiteral *OrderId = IntegerLiteral::Create(
-        AST, llvm::APInt(UIntTySize, OrderID), AST.UnsignedIntTy,
-        SourceLocation());
+    IntegerLiteral *OrderId =
+        IntegerLiteral::Create(AST, llvm::APInt(UIntTySize, OrderID),
+                               AST.UnsignedIntTy, SourceLocation());
     Args.append({Space, RangeSize, Index, OrderId, Name});
   }
 }

[hekota]

I am going to split the PR into 2 to make it easier to review.