Anastasia added a comment. In https://reviews.llvm.org/D48419#1139799, @yaxunl wrote:
> In https://reviews.llvm.org/D48419#1139749, @Anastasia wrote: > > > In https://reviews.llvm.org/D48419#1139601, @yaxunl wrote: > > > > > Did you notice the bug that C++ silently allows implicit casting of a > > > pointer to a pointer type with different address space? > > > > > > Do you have a fix for that? > > > > > > I didn't think it did because if I run > > `test/SemaOpenCL/address-spaces-conversions-cl2.0.cl` in `-cl-std=c++` it > > gives me errors when I initialize a pointer with different AS pointer: > > > > error: cannot initialize a variable of type '__global int *' with an > > lvalue of type '__local int *' > > error: assigning to '__global int *' from incompatible type '__local int > > *' > > error: comparison of distinct pointer types ('__global int *' and > > '__local int *') > > > > > > Do you have an example code somewhere? > > > Actually this only happens when there is an explicit cast: > > $ cat address-space-cast.cpp > // RUN: %clang_cc1 %s -triple=amdgcn-amd-amdhsa -emit-llvm -o - | FileCheck > %s > > #define __private__ __attribute__((address_space(5))) > > void f(char* q) { > // CHECK: addrspacecast > __private__ char* p = (__private__ char*)q; > //__private__ char* p = q; > } > $clang -cc1 -triple=amdgcn-amd-amdhsa address-space-cast.cpp -ast-dump > TranslationUnitDecl 0x699f418 <<invalid sloc>> <invalid sloc> > |-TypedefDecl 0x699fab0 <<invalid sloc>> <invalid sloc> implicit __int128_t > '__int128' > | `-BuiltinType 0x699f770 '__int128' > |-TypedefDecl 0x699fb18 <<invalid sloc>> <invalid sloc> implicit > __uint128_t 'unsigned __int128' > | `-BuiltinType 0x699f790 'unsigned __int128' > |-TypedefDecl 0x699fe58 <<invalid sloc>> <invalid sloc> implicit > __NSConstantString '__NSConstantString_tag' > | `-RecordType 0x699fc00 '__NSConstantString_tag' > | `-CXXRecord 0x699fb68 '__NSConstantString_tag' > |-TypedefDecl 0x699fef0 <<invalid sloc>> <invalid sloc> implicit > __builtin_va_list 'char *' > | `-PointerType 0x699feb0 'char *' > | `-BuiltinType 0x699f4b0 'char' > `-FunctionDecl 0x69a0020 <address-space-cast.cpp:5:1, line:9:1> line:5:6 f > 'void (char *)' > |-ParmVarDecl 0x699ff58 <col:8, col:14> col:14 used q 'char *' > `-CompoundStmt 0x69e4130 <col:17, line:9:1> > `-DeclStmt 0x69e4118 <line:3:21, line:7:45> > `-VarDecl 0x69e4000 <line:3:21, line:7:44> col:21 p > '__attribute__((address_space(5))) char *' cinit > `-CStyleCastExpr 0x69e40f0 <col:25, col:44> > '__attribute__((address_space(5))) char *' <NoOp> > `-ImplicitCastExpr 0x69e40d8 <col:44> > '__attribute__((address_space(5))) char *' <NoOp> > `-ImplicitCastExpr 0x69e40c0 <col:44> 'char *' <LValueToRValue> > `-DeclRefExpr 0x69e4080 <col:44> 'char *' lvalue ParmVar > 0x699ff58 'q' 'char *' > > > > In the AST there is a CStyleCast and an ImplicitCast, both are NoOp, which > will becomes bitcast in codegen and causes invalid bitcast instruction. Yes this extra `ImplicitCastExpr` doesn't appear in OpenCL C and also `CStyleCastExpr` is correctly attributed as `AddressSpaceConversion` CStyleCastExpr 0xc490810 <col:23, col:40> 'char *' <AddressSpaceConversion> Since C++ uses conversion ranking rules the Sema code for it largely goes through the different path than in C. I think fixing address spaces in C++ or OpenCL C++ will need quite a bit of more work. I am planning to look at further issues in the next weeks, but not sure when... I hope it doesn't prevent us to go ahead with this parsing fix. https://reviews.llvm.org/D48419 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
