diff options
| -rw-r--r-- | clang/lib/CodeGen/CGCall.cpp | 13 | ||||
| -rw-r--r-- | clang/test/CodeGen/nonnull.c | 20 |
2 files changed, 31 insertions, 2 deletions
diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp index 45a62590898..c95680ccda6 100644 --- a/clang/lib/CodeGen/CGCall.cpp +++ b/clang/lib/CodeGen/CGCall.cpp @@ -1557,8 +1557,17 @@ void CodeGenFunction::EmitFunctionProlog(const CGFunctionInfo &FI, llvm::Value *V = AI; if (const ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(Arg)) { - if ((NNAtt && NNAtt->isNonNull(PVD->getFunctionScopeIndex())) || - PVD->hasAttr<NonNullAttr>()) + // FIXME: __attribute__((nonnull)) can also be applied to: + // - references to pointers, where the pointee is known to be + // nonnull (apparently a Clang extension) + // - transparent unions containing pointers + // In the former case, LLVM IR cannot represent the constraint. In + // the latter case, we have no guarantee that the transparent union + // is in fact passed as a pointer. + if (((NNAtt && NNAtt->isNonNull(PVD->getFunctionScopeIndex())) || + PVD->hasAttr<NonNullAttr>()) && + (PVD->getType()->isAnyPointerType() || + PVD->getType()->isBlockPointerType())) AI->addAttr(llvm::AttributeSet::get(getLLVMContext(), AI->getArgNo() + 1, llvm::Attribute::NonNull)); diff --git a/clang/test/CodeGen/nonnull.c b/clang/test/CodeGen/nonnull.c index 4d6cc4568d8..e234105d9ad 100644 --- a/clang/test/CodeGen/nonnull.c +++ b/clang/test/CodeGen/nonnull.c @@ -21,3 +21,23 @@ int * bar3() __attribute__((returns_nonnull)) { return &a; } +// CHECK: define i32 @bar4(i32 %n, i32* nonnull %p) +int bar4(int n, int *p) __attribute__((nonnull)) { + return n + *p; +} + +// CHECK: define i32 @bar5(i32 %n, i32* nonnull %p) +int bar5(int n, int *p) __attribute__((nonnull(1, 2))) { + return n + *p; +} + +typedef union { + unsigned long long n; + int *p; + double d; +} TransparentUnion __attribute__((transparent_union)); + +// CHECK: define i32 @bar6(i64 % +int bar6(TransparentUnion tu) __attribute__((nonnull(1))) { + return *tu.p; +} |
