[clang] [HLSL] Desugar type when converting from a ConstantArrayType to an ArrayParameterType (PR #126561)

[Sarah Spall via cfe-commits]

https://github.com/spall created https://github.com/llvm/llvm-project/pull/126561

Desugar type when converting from a ConstantArrayType to an ArrayParameterType in getArrayParameterType
Closes #125743 

>From 199395c935fc1da70db91bba94a1ea86afb83bf9 Mon Sep 17 00:00:00 2001
From: Sarah Spall <sarahspall at microsoft.com>
Date: Mon, 10 Feb 2025 08:17:01 -0800
Subject: [PATCH 1/2] remove sugar

---
 clang/lib/AST/ASTContext.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index de617860b70040b..e3b44bdbe3dc52f 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -3902,7 +3902,7 @@ QualType ASTContext::getArrayParameterType(QualType Ty) const {
   if (Ty->isArrayParameterType())
     return Ty;
   assert(Ty->isConstantArrayType() && "Ty must be an array type.");
-  const auto *ATy = cast<ConstantArrayType>(Ty);
+  const auto *ATy = cast<ConstantArrayType>(Ty.getDesugaredType(*this));
   llvm::FoldingSetNodeID ID;
   ATy->Profile(ID, *this, ATy->getElementType(), ATy->getZExtSize(),
                ATy->getSizeExpr(), ATy->getSizeModifier(),

>From 792a767a03b442011ebf5a9061d3c2a077676f45 Mon Sep 17 00:00:00 2001
From: Sarah Spall <sarahspall at microsoft.com>
Date: Mon, 10 Feb 2025 09:37:59 -0800
Subject: [PATCH 2/2] ast test

---
 clang/test/AST/HLSL/TypdefArrayParam.hlsl | 57 +++++++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 clang/test/AST/HLSL/TypdefArrayParam.hlsl

diff --git a/clang/test/AST/HLSL/TypdefArrayParam.hlsl b/clang/test/AST/HLSL/TypdefArrayParam.hlsl
new file mode 100644
index 000000000000000..c6ae168f8406456
--- /dev/null
+++ b/clang/test/AST/HLSL/TypdefArrayParam.hlsl
@@ -0,0 +1,57 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.0-library -finclude-default-header -x hlsl -ast-dump %s | FileCheck %s
+
+typedef uint4 uint32_t4;
+typedef uint32_t4 uint32_t8[2];
+
+// CHECK-LABEL: FunctionDecl {{.*}} used Accumulate 'uint32_t (uint32_t4[2])'
+// CHECK-NEXT: ParmVarDecl {{.*}} used V 'uint32_t4[2]'
+uint32_t Accumulate(uint32_t8 V) {
+  uint32_t4 SumVec = V[0] + V[1];
+  return SumVec.x + SumVec.y + SumVec.z + SumVec.w;
+}
+
+// CHECK-LABEL: FunctionDecl {{.*}} used InOutAccu 'void (inout uint32_t4[2])'
+// CHECK-NEXT: ParmVarDecl {{.*}} used V 'uint32_t4[2]'
+// CHECK-NEXT: HLSLParamModifierAttr {{.*}} inout
+void InOutAccu(inout uint32_t8 V) {
+  uint32_t4 SumVec = V[0] + V[1];
+  V[0] = SumVec;
+}
+
+// CHECK-LABEL: call1
+// CHECK: CallExpr {{.*}} 'void'
+// CHECK-NEXT: ImplicitCastExpr {{.*}} 'void (*)(inout uint32_t4[2])' <FunctionToPointerDecay>
+// CHECK-NEXT: DeclRefExpr {{.*}} 'void (inout uint32_t4[2])' lvalue Function {{.*}} 'InOutAccu' 'void (inout uint32_t4[2])'
+// CHECK-NEXT: HLSLOutArgExpr {{.*}} 'uint32_t4[2]' lvalue inout
+// CHECK-NEXT: OpaqueValueExpr {{.*}} 'uint32_t8':'uint32_t4[2]' lvalue
+// CHECK-NEXT: DeclRefExpr {{.*}} 'uint32_t8':'uint32_t4[2]' lvalue Var {{.*}} 'B' 'uint32_t8':'uint32_t4[2]'
+// CHECK-NEXT: OpaqueValueExpr {{.*}} 'uint32_t4[2]' lvalue
+// CHECK-NEXT: ImplicitCastExpr {{.*}} 'uint32_t4[2]' <HLSLArrayRValue>
+// CHECK-NEXT: OpaqueValueExpr {{.*}} 'uint32_t8':'uint32_t4[2]' lvalue
+// CHECK-NEXT: DeclRefExpr {{.*}} 'uint32_t8':'uint32_t4[2]' lvalue Var {{.*}} 'B' 'uint32_t8':'uint32_t4[2]'
+// CHECK-NEXT: BinaryOperator {{.*}} 'uint32_t8':'uint32_t4[2]' lvalue '='
+// CHECK-NEXT: OpaqueValueExpr {{.*}} 'uint32_t8':'uint32_t4[2]' lvalue
+// CHECK-NEXT: DeclRefExpr {{.*}} 'uint32_t8':'uint32_t4[2]' lvalue Var {{.*}} 'B' 'uint32_t8':'uint32_t4[2]'
+// CHECK-NEXT: ImplicitCastExpr {{.*}} 'uint32_t4[2]' <HLSLArrayRValue>
+// CHECK-NEXT: OpaqueValueExpr {{.*}} 'uint32_t4[2]' lvalue
+// CHECK-NEXT: ImplicitCastExpr {{.*}} 'uint32_t4[2]' <HLSLArrayRValue>
+// CHECK-NEXT: OpaqueValueExpr {{.*}} 'uint32_t8':'uint32_t4[2]' lvalue
+// CHECK-NEXT: DeclRefExpr {{.*}} 'uint32_t8':'uint32_t4[2]' lvalue Var {{.*}} 'B' 'uint32_t8':'uint32_t4[2]'
+void call1() {
+  uint32_t4 A = {1,2,3,4};
+  uint32_t8 B = {A,A};
+  InOutAccu(B);
+}
+
+// CHECK-LABEL: call2
+// CHECK: VarDecl {{.*}} D 'uint32_t':'unsigned int' cinit
+// CHECK-NEXT: CallExpr {{.*}} 'uint32_t':'unsigned int'
+// CHECK-NEXT: ImplicitCastExpr {{.*}} 'uint32_t (*)(uint32_t4[2])' <FunctionToPointerDecay>
+// CHECK-NEXT: DeclRefExpr {{.*}} 'uint32_t (uint32_t4[2])' lvalue Function {{.*}} 'Accumulate' 'uint32_t (uint32_t4[2])'
+// CHECK-NEXT: ImplicitCastExpr {{.*}} 'uint4[2]' <HLSLArrayRValue>
+// CHECK-NEXT: DeclRefExpr {{.*}} 'uint4[2]' lvalue Var {{.*}} 'C' 'uint4[2]'
+void call2() {
+  uint4 A = {1,2,3,4};
+  uint4 C[2] = {A,A};
+  uint32_t D = Accumulate(C);
+}