[clang] [HLSL] Mark vector and matrix constructor-turned-InitListExprs as ListInitializations (PR #192151)

[Alex Sepkowski via cfe-commits]

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@@ -0,0 +1,80 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-compute -x hlsl -ast-dump -o - %s | FileCheck %s
+
+// Verify that HLSL vector/matrix paren-syntax constructors inside template
+// functions produce the correct AST after template instantiation. The key
+// property is that the CXXFunctionalCastExpr wrapping an InitListExpr survives
+// re-instantiation intact.
+
+typedef int int2 __attribute__((ext_vector_type(2)));
+typedef float float2 __attribute__((ext_vector_type(2)));
+typedef float float3 __attribute__((ext_vector_type(3)));
+typedef float float4 __attribute__((ext_vector_type(4)));
+typedef float float2x2 __attribute__((matrix_type(2, 2)));
+
+// Basic vector constructors in a template.
+template<typename T>
+void vector_constructors() {
+// CHECK-LABEL: FunctionDecl {{.*}} used vector_constructors 'void ()' implicit_instantiation
+// CHECK: VarDecl {{.*}} a 'int2':'vector<int, 2>' cinit
+// CHECK-NEXT: CXXFunctionalCastExpr {{.*}} 'int2':'vector<int, 2>' functional cast to int2 <NoOp>
+// CHECK-NEXT: InitListExpr {{.*}} 'int2':'vector<int, 2>'
+// CHECK-NEXT: IntegerLiteral {{.*}} 'int' 0
+// CHECK-NEXT: IntegerLiteral {{.*}} 'int' 0
+// CHECK: VarDecl {{.*}} b 'float3':'vector<float, 3>' cinit
+// CHECK-NEXT: CXXFunctionalCastExpr {{.*}} 'float3':'vector<float, 3>' functional cast to float3 <NoOp>
+// CHECK-NEXT: InitListExpr {{.*}} 'float3':'vector<float, 3>'
+// CHECK-NEXT: FloatingLiteral {{.*}} 'float' 1.000000e+00
+// CHECK-NEXT: FloatingLiteral {{.*}} 'float' 2.000000e+00
+// CHECK-NEXT: FloatingLiteral {{.*}} 'float' 3.000000e+00
+  int2 a = int2(0, 0);
+  float3 b = float3(1.0f, 2.0f, 3.0f);
+}
+
+
+// Nested vector constructor: float4 built from a float2 + two scalars.
+template<typename T>
+void vector_constructors_nested() {
+// CHECK-LABEL: FunctionDecl {{.*}} used vector_constructors_nested 'void ()' implicit_instantiation
+// CHECK: VarDecl {{.*}} used v 'float2':'vector<float, 2>' cinit
+// CHECK-NEXT: CXXFunctionalCastExpr {{.*}} 'float2':'vector<float, 2>' functional cast to float2 <NoOp>
+// CHECK-NEXT: InitListExpr {{.*}} 'float2':'vector<float, 2>'
+// CHECK-NEXT: FloatingLiteral {{.*}} 'float' 1.000000e+00
+// CHECK-NEXT: FloatingLiteral {{.*}} 'float' 2.000000e+00
+// CHECK: VarDecl {{.*}} w 'float4':'vector<float, 4>' cinit
+// CHECK-NEXT: CXXFunctionalCastExpr {{.*}} 'float4':'vector<float, 4>' functional cast to float4 <NoOp>
+// CHECK-NEXT: InitListExpr {{.*}} 'float4':'vector<float, 4>'
+// CHECK-NEXT: ImplicitCastExpr {{.*}} 'float' <LValueToRValue>
+// CHECK-NEXT: ArraySubscriptExpr {{.*}} 'float' lvalue vectorcomponent
+// CHECK-NEXT: DeclRefExpr {{.*}} 'float2':'vector<float, 2>' lvalue Var {{.*}} 'v' 'float2':'vector<float, 2>'
+// CHECK-NEXT: IntegerLiteral {{.*}} '__size_t':'unsigned long' 0
+// CHECK-NEXT: ImplicitCastExpr {{.*}} 'float' <LValueToRValue>
+// CHECK-NEXT: ArraySubscriptExpr {{.*}} 'float' lvalue vectorcomponent
+// CHECK-NEXT: DeclRefExpr {{.*}} 'float2':'vector<float, 2>' lvalue Var {{.*}} 'v' 'float2':'vector<float, 2>'
+// CHECK-NEXT: IntegerLiteral {{.*}} '__size_t':'unsigned long' 1
+// CHECK-NEXT: FloatingLiteral {{.*}} 'float' 3.000000e+00
+// CHECK-NEXT: FloatingLiteral {{.*}} 'float' 4.000000e+00
+  float2 v = float2(1.0f, 2.0f);
+  float4 w = float4(v, 3.0f, 4.0f);
+}
+
+// Matrix constructor in a template.
+template<typename T>
+void matrix_constructors() {
+// CHECK-LABEL: FunctionDecl {{.*}} used matrix_constructors 'void ()' implicit_instantiation
+// CHECK: VarDecl {{.*}} m 'float2x2':'matrix<float, 2, 2>' cinit
+// CHECK-NEXT: CXXFunctionalCastExpr {{.*}} 'float2x2':'matrix<float, 2, 2>' functional cast to float2x2 <NoOp>
+// CHECK-NEXT: InitListExpr {{.*}} 'float2x2':'matrix<float, 2, 2>'
+// CHECK-NEXT: FloatingLiteral {{.*}} 'float' 1.000000e+00
+// CHECK-NEXT: FloatingLiteral {{.*}} 'float' 2.000000e+00
+// CHECK-NEXT: FloatingLiteral {{.*}} 'float' 3.000000e+00
+// CHECK-NEXT: FloatingLiteral {{.*}} 'float' 4.000000e+00
+  float2x2 m = float2x2(1.0f, 2.0f, 3.0f, 4.0f);
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alsepkow wrote:

Is it valid to add a test case for a nested matrix?

https://github.com/llvm/llvm-project/pull/192151