From db27b5fb2d7fc50b8962b2c95e4d43b90c69b1f0 Mon Sep 17 00:00:00 2001 From: Daniel Dunbar Date: Tue, 19 Apr 2011 23:10:47 +0000 Subject: [PATCH] IRgen/ARM: Fix a think-o in conversion-to-null for member function pointers, we were computing the conversion as (ptr != 0 && non-virtual), when it should be (ptr != 0 || is-virtual). - Test to follow in LLVM test-suite. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@129830 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/ItaniumCXXABI.cpp | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/lib/CodeGen/ItaniumCXXABI.cpp b/lib/CodeGen/ItaniumCXXABI.cpp index c77b0bf6b8..a53ef1a265 100644 --- a/lib/CodeGen/ItaniumCXXABI.cpp +++ b/lib/CodeGen/ItaniumCXXABI.cpp @@ -652,20 +652,21 @@ ItaniumCXXABI::EmitMemberPointerIsNotNull(CodeGenFunction &CGF, return Builder.CreateICmpNE(MemPtr, NegativeOne, "memptr.tobool"); } - // In Itanium, a member function pointer is null if 'ptr' is null. + // In Itanium, a member function pointer is not null if 'ptr' is not null. llvm::Value *Ptr = Builder.CreateExtractValue(MemPtr, 0, "memptr.ptr"); llvm::Constant *Zero = llvm::ConstantInt::get(Ptr->getType(), 0); llvm::Value *Result = Builder.CreateICmpNE(Ptr, Zero, "memptr.tobool"); - // In ARM, it's that, plus the low bit of 'adj' must be zero. + // On ARM, a member function pointer is also non-null if the low bit of 'adj' + // (the virtual bit) is set. if (IsARM) { llvm::Constant *One = llvm::ConstantInt::get(Ptr->getType(), 1); llvm::Value *Adj = Builder.CreateExtractValue(MemPtr, 1, "memptr.adj"); llvm::Value *VirtualBit = Builder.CreateAnd(Adj, One, "memptr.virtualbit"); - llvm::Value *IsNotVirtual = Builder.CreateICmpEQ(VirtualBit, Zero, - "memptr.notvirtual"); - Result = Builder.CreateAnd(Result, IsNotVirtual); + llvm::Value *IsVirtual = Builder.CreateICmpNE(VirtualBit, Zero, + "memptr.isvirtual"); + Result = Builder.CreateOr(Result, IsVirtual); } return Result; -- 2.50.1