[PATCH] D102689: [C++4OpenCL] Allow address space conversion in reinterpret_cast

[Ole Strohm via Phabricator via cfe-commits]

olestrohm updated this revision to Diff 347922.
olestrohm added a comment.

I've cleaned up the check. The qualifiers of SrcType are removed prior to this function, so only DestType needs to have the address space removed.

reinterpret_cast only allows integral types, so structs are not an issue here, though pointers are.
However this change only allows converting between pointer types as long as they're the exact same, save for the outermost address space.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D102689/new/

https://reviews.llvm.org/D102689

Files:
  clang/lib/Sema/SemaCast.cpp
  clang/test/CodeGenOpenCLCXX/reinterpret_cast.clcpp
  clang/test/SemaOpenCLCXX/reinterpret-cast.clcpp


Index: clang/test/SemaOpenCLCXX/reinterpret-cast.clcpp
===================================================================
--- clang/test/SemaOpenCLCXX/reinterpret-cast.clcpp
+++ clang/test/SemaOpenCLCXX/reinterpret-cast.clcpp
@@ -4,6 +4,11 @@
 typedef int int3 __attribute__((ext_vector_type(3)));
 typedef int int4 __attribute__((ext_vector_type(4)));
 
+struct X {};
+
+__global int g = 0;
+__global int *__global g_ptr = &g;
+
 kernel void foo() {
   // Testing conversions between vectors and vectors/scalars
   long l1;
@@ -13,6 +18,17 @@
   auto i2_to_i = reinterpret_cast<int>(i2); // expected-error{{reinterpret_cast from vector 'int2' (vector of 2 'int' values) to scalar 'int' of different size}}
   auto i2_to_i2 = reinterpret_cast<int2>(i2);
 
+  // Testing reinterpret_cast with address spaces.
+  __private short s;
+  auto s2 = reinterpret_cast<__private short>(s);
+  auto s3 = reinterpret_cast<decltype(s)>(s);
+  auto s4 = reinterpret_cast<__global short>(s);
+
+  __private X x;
+  auto x2 = reinterpret_cast<__private X>(x); // expected-error{{reinterpret_cast from '__private X' to '__private X' is not allowed}}
+
+  auto ptr = reinterpret_cast<__global int* __private>(g_ptr);
+
   // Only integral types (and pointer/references) can be reinterpret casted to themselves.
   // Currently this does not include any opencl types.
   reserve_id_t r_id1;
Index: clang/test/CodeGenOpenCLCXX/reinterpret_cast.clcpp
===================================================================
--- clang/test/CodeGenOpenCLCXX/reinterpret_cast.clcpp
+++ clang/test/CodeGenOpenCLCXX/reinterpret_cast.clcpp
@@ -11,6 +11,17 @@
   //CHECK: bitcast i64 %{{[0-9]+}} to <2 x i32>
   auto i2 = reinterpret_cast<int2>(l);
 
+  __private short s1;
+  // CHECK: %{{[0-9]+}} = load i16, i16* %s1, align 2
+  // CHECK-NEXT: store i16 %{{[0-9]+}}, i16* %s2, align 2
+  auto s2 = reinterpret_cast<__private short>(s1);
+  // CHECK: %{{[0-9]+}} = load i16, i16* %s1, align 2
+  // CHECK-NEXT: store i16 %{{[0-9]+}}, i16* %s3, align 2
+  auto s3 = reinterpret_cast<decltype(s1)>(s1);
+  // CHECK: %{{[0-9]+}} = load i16, i16* %s1, align 2
+  // CHECK-NEXT: store i16 %{{[0-9]+}}, i16* %s4, align 2
+  auto s4 = reinterpret_cast<__global short>(s1);
+
   int4 i4;
   //CHECK: bitcast <4 x i32> %{{[0-9]+}} to <2 x i64>
   auto l2 = reinterpret_cast<long2>(i4);
Index: clang/lib/Sema/SemaCast.cpp
===================================================================
--- clang/lib/Sema/SemaCast.cpp
+++ clang/lib/Sema/SemaCast.cpp
@@ -2356,7 +2356,7 @@
     return TC_Failed;
   }
 
-  if (SrcType == DestType) {
+  if (SrcType == Self.Context.removeAddrSpaceQualType(DestType)) {
     // C++ 5.2.10p2 has a note that mentions that, subject to all other
     // restrictions, a cast to the same type is allowed so long as it does not
     // cast away constness. In C++98, the intent was not entirely clear here,


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