Revert "[HLSL] Make it possible to assign an array from a cbuffer (#134174)"

This reverts commit 52a5332.

Author: spall

clang/lib/Sema/SemaExprCXX.cpp

@@ -4745,13 +4745,19 @@ Sema::PerformImplicitConversion(Expr *From, QualType ToType,
   case ICK_HLSL_Array_RValue:
     if (ToType->isArrayParameterType()) {
       FromType = Context.getArrayParameterType(FromType);
-    } else if (FromType->isArrayParameterType()) {
+      From = ImpCastExprToType(From, FromType, CK_HLSLArrayRValue, VK_PRValue,
+                               /*BasePath=*/nullptr, CCK)
+                 .get();
+    } else { // FromType must be ArrayParameterType
+      assert(FromType->isArrayParameterType() &&
+             "FromType must be ArrayParameterType in ICK_HLSL_Array_RValue \
+              if it is not ToType");
       const ArrayParameterType *APT = cast<ArrayParameterType>(FromType);
       FromType = APT->getConstantArrayType(Context);
+      From = ImpCastExprToType(From, FromType, CK_HLSLArrayRValue, VK_PRValue,
+                               /*BasePath=*/nullptr, CCK)
+                 .get();
     }
-    From = ImpCastExprToType(From, FromType, CK_HLSLArrayRValue, VK_PRValue,
-                             /*BasePath=*/nullptr, CCK)
-               .get();
     break;
 
   case ICK_Function_To_Pointer:

clang/lib/Sema/SemaOverload.cpp

@@ -2275,16 +2275,17 @@ static bool IsStandardConversion(Sema &S, Expr* From, QualType ToType,
     // handling here.
     if (ToType->isArrayParameterType()) {
       FromType = S.Context.getArrayParameterType(FromType);
+      SCS.First = ICK_HLSL_Array_RValue;
     } else if (FromType->isArrayParameterType()) {
       const ArrayParameterType *APT = cast<ArrayParameterType>(FromType);
       FromType = APT->getConstantArrayType(S.Context);
+      SCS.First = ICK_HLSL_Array_RValue;
+    } else {
+      SCS.First = ICK_Identity;
     }
 
-    SCS.First = ICK_HLSL_Array_RValue;
-
-    // Don't consider qualifiers, which include things like address spaces
-    if (FromType.getCanonicalType().getUnqualifiedType() !=
-        ToType.getCanonicalType().getUnqualifiedType())
+    if (S.Context.getCanonicalType(FromType) !=
+        S.Context.getCanonicalType(ToType))
       return false;
 
     SCS.setAllToTypes(ToType);

clang/test/CodeGenHLSL/ArrayAssignable.hlsl

@@ -1,23 +1,4 @@
-// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -finclude-default-header -emit-llvm -disable-llvm-passes -o - %s | FileCheck %s
-
-struct S {
-  int x;
-  float f;
-};
-
-// CHECK: [[CBLayout:%.*]] = type <{ [2 x float], [2 x <4 x i32>], [2 x [2 x i32]], [1 x target("dx.Layout", %S, 8, 0, 4)] }>
-// CHECK: @CBArrays.cb = global target("dx.CBuffer", target("dx.Layout", [[CBLayout]], 136, 0, 32, 64, 128))
-// CHECK: @c1 = external addrspace(2) global [2 x float], align 4
-// CHECK: @c2 = external addrspace(2) global [2 x <4 x i32>], align 16
-// CHECK: @c3 = external addrspace(2) global [2 x [2 x i32]], align 4
-// CHECK: @c4 = external addrspace(2) global [1 x target("dx.Layout", %S, 8, 0, 4)], align 4
-
-cbuffer CBArrays {
-  float c1[2];
-  int4 c2[2];
-  int c3[2][2];
-  S c4[1];
-}
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -emit-llvm -disable-llvm-passes -o - %s | FileCheck %s --enable-var-scope
 
 // CHECK-LABEL: define void {{.*}}arr_assign1
 // CHECK: [[Arr:%.*]] = alloca [2 x i32], align 4
@@ -135,45 +116,3 @@ void arr_assign7() {
   int Arr2[2][2] = {{0, 0}, {1, 1}};
   (Arr = Arr2)[0] = {6, 6};
 }
-
-// Verify you can assign from a cbuffer array
-
-// CHECK-LABEL: define void {{.*}}arr_assign8
-// CHECK: [[C:%.*]] = alloca [2 x float], align 4
-// CHECK-NEXT: call void @llvm.memcpy.p0.p0.i32(ptr align 4 [[C]], ptr align 4 {{.*}}, i32 8, i1 false)
-// CHECK-NEXT: call void @llvm.memcpy.p0.p2.i32(ptr align 4 [[C]], ptr addrspace(2) align 4 @c1, i32 8, i1 false)
-// CHECK-NEXT: ret void
-void arr_assign8() {
-  float C[2] = {1.0, 2.0};
-  C = c1;
-}
-
-// CHECK-LABEL: define void {{.*}}arr_assign9
-// CHECK: [[C:%.*]] = alloca [2 x <4 x i32>], align 16
-// CHECK-NEXT: call void @llvm.memcpy.p0.p0.i32(ptr align 16 [[C]], ptr align 16 {{.*}}, i32 32, i1 false)
-// CHECK-NEXT: call void @llvm.memcpy.p0.p2.i32(ptr align 16 [[C]], ptr addrspace(2) align 16 @c2, i32 32, i1 false)
-// CHECK-NEXT: ret void
-void arr_assign9() {
-  int4 C[2] = {1,2,3,4,5,6,7,8};
-  C = c2;
-}
-
-// CHECK-LABEL: define void {{.*}}arr_assign10
-// CHECK: [[C:%.*]] = alloca [2 x [2 x i32]], align 4
-// CHECK-NEXT: call void @llvm.memcpy.p0.p0.i32(ptr align 4 [[C]], ptr align 4 {{.*}}, i32 16, i1 false)
-// CHECK-NEXT: call void @llvm.memcpy.p0.p2.i32(ptr align 4 [[C]], ptr addrspace(2) align 4 @c3, i32 16, i1 false)
-// CHECK-NEXT: ret void
-void arr_assign10() {
-  int C[2][2] = {1,2,3,4};
-  C = c3;
-}
-
-// CHECK-LABEL: define void {{.*}}arr_assign11
-// CHECK: [[C:%.*]] = alloca [1 x %struct.S], align 4
-// CHECK: call void @llvm.memcpy.p0.p2.i32(ptr align 4 [[C]], ptr addrspace(2) align 4 @c4, i32 8, i1 false)
-// CHECK-NEXT: ret void
-void arr_assign11() {
-  S s = {1, 2.0};
-  S C[1] = {s};
-  C = c4;
-}