Let llvm.objectsize be conservative with null pointers
D28494 adds another parameter to @llvm.objectsize. Clang needs to be
sure to pass that third arg whenever applicable.
llvm-svn: 298431
diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 005c824..8175890 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -470,10 +470,13 @@
assert(Ptr->getType()->isPointerTy() &&
"Non-pointer passed to __builtin_object_size?");
- // LLVM only supports 0 and 2, make sure that we pass along that as a boolean.
- auto *CI = ConstantInt::get(Builder.getInt1Ty(), (Type & 2) >> 1);
Value *F = CGM.getIntrinsic(Intrinsic::objectsize, {ResType, Ptr->getType()});
- return Builder.CreateCall(F, {Ptr, CI});
+
+ // LLVM only supports 0 and 2, make sure that we pass along that as a boolean.
+ Value *Min = Builder.getInt1((Type & 2) != 0);
+ // For GCC compatability, __builtin_object_size treat NULL as unknown size.
+ Value *NullIsUnknown = Builder.getTrue();
+ return Builder.CreateCall(F, {Ptr, Min, NullIsUnknown});
}
// Many of MSVC builtins are on both x64 and ARM; to avoid repeating code, we
diff --git a/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp
index 1118bfa..1a95eb1 100644
--- a/clang/lib/CodeGen/CGExpr.cpp
+++ b/clang/lib/CodeGen/CGExpr.cpp
@@ -581,10 +581,11 @@
llvm::Type *Tys[2] = { IntPtrTy, Int8PtrTy };
llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, Tys);
llvm::Value *Min = Builder.getFalse();
+ llvm::Value *NullIsUnknown = Builder.getFalse();
llvm::Value *CastAddr = Builder.CreateBitCast(Ptr, Int8PtrTy);
- llvm::Value *LargeEnough =
- Builder.CreateICmpUGE(Builder.CreateCall(F, {CastAddr, Min}),
- llvm::ConstantInt::get(IntPtrTy, Size));
+ llvm::Value *LargeEnough = Builder.CreateICmpUGE(
+ Builder.CreateCall(F, {CastAddr, Min, NullIsUnknown}),
+ llvm::ConstantInt::get(IntPtrTy, Size));
Checks.push_back(std::make_pair(LargeEnough, SanitizerKind::ObjectSize));
}