Author: Timm Baeder Date: 2024-12-09T16:57:49+01:00 New Revision: 6168739f00616f34354e0b34852398aeced98f53
URL: https://github.com/llvm/llvm-project/commit/6168739f00616f34354e0b34852398aeced98f53 DIFF: https://github.com/llvm/llvm-project/commit/6168739f00616f34354e0b34852398aeced98f53.diff LOG: [clang][bytecode] Reject memcpy sizes with element size remainder (#119209) Added: Modified: clang/lib/AST/ByteCode/InterpBuiltin.cpp clang/test/AST/ByteCode/builtin-functions.cpp Removed: ################################################################################ diff --git a/clang/lib/AST/ByteCode/InterpBuiltin.cpp b/clang/lib/AST/ByteCode/InterpBuiltin.cpp index 9f2e64b3faeff2..a0de193ec32a2f 100644 --- a/clang/lib/AST/ByteCode/InterpBuiltin.cpp +++ b/clang/lib/AST/ByteCode/InterpBuiltin.cpp @@ -1860,6 +1860,21 @@ static bool interp__builtin_memcpy(InterpState &S, CodePtr OpPC, return false; } + QualType ElemType; + if (SrcPtr.getFieldDesc()->isArray()) + ElemType = SrcPtr.getFieldDesc()->getElemQualType(); + else + ElemType = SrcPtr.getType(); + + unsigned ElemSize = + S.getASTContext().getTypeSizeInChars(ElemType).getQuantity(); + if (Size.urem(ElemSize) != 0) { + S.FFDiag(S.Current->getSource(OpPC), + diag::note_constexpr_memcpy_unsupported) + << Move << /*IsWchar=*/false << 0 << ElemType << Size << ElemSize; + return false; + } + // As a last resort, reject dummy pointers. if (DestPtr.isDummy() || SrcPtr.isDummy()) return false; diff --git a/clang/test/AST/ByteCode/builtin-functions.cpp b/clang/test/AST/ByteCode/builtin-functions.cpp index bd453d6d342d3f..a67b6b665f3790 100644 --- a/clang/test/AST/ByteCode/builtin-functions.cpp +++ b/clang/test/AST/ByteCode/builtin-functions.cpp @@ -1197,4 +1197,14 @@ namespace BuiltinMemcpy { return b; } static_assert(simpleMove() == 12); + + constexpr int memcpyTypeRem() { // ref-error {{never produces a constant expression}} + int a = 12; + int b = 0; + __builtin_memmove(&b, &a, 1); // both-note {{'memmove' not supported: size to copy (1) is not a multiple of size of element type 'int'}} \ + // ref-note {{not supported}} + return b; + } + static_assert(memcpyTypeRem() == 12); // both-error {{not an integral constant expression}} \ + // both-note {{in call to}} } _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
