Sanjoy Das 2582e690b7 [TBAA] Drop support for "old style" scalar TBAA tags
Summary:
We've had support for auto upgrading old style scalar TBAA access
metadata tags into the "new" struct path aware TBAA metadata for 3 years
now.  The only way to actually generate old style TBAA was explicitly
through the IRBuilder API.  I think this is a good time for dropping
support for old style scalar TBAA.

I'm not removing support for textual or bitcode upgrade -- if you have
IR with the old style scalar TBAA tags that go through the AsmParser orf
the bitcode parser before LLVM sees them, they will keep working as
usual.

Note:

  %val = load i32, i32* %ptr, !tbaa !N
  !N = < scalar tbaa node >

is equivalent to

  %val = load i32, i32* %ptr, !tbaa !M
  !N = < scalar tbaa node >
  !M = !{!N, !N, 0}

Reviewers: manmanren, chandlerc, sunfish

Subscribers: mcrosier, llvm-commits, mgorny

Differential Revision: https://reviews.llvm.org/D26229

llvm-svn: 286291
2016-11-08 20:46:01 +00:00

64 lines
2.0 KiB
C++

//===--- TBAATest.cpp - Mixed TBAA unit tests -----------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/AliasAnalysisEvaluator.h"
#include "llvm/Analysis/Passes.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/MDBuilder.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/IR/Verifier.h"
#include "llvm/Support/CommandLine.h"
#include "gtest/gtest.h"
namespace llvm {
namespace {
class OldTBAATest : public testing::Test {
protected:
OldTBAATest() : M("MixedTBAATest", C), MD(C) {}
LLVMContext C;
Module M;
MDBuilder MD;
};
TEST_F(OldTBAATest, checkVerifierBehavior) {
// C++ unit test case to avoid going through the auto upgrade logic.
FunctionType *FTy = FunctionType::get(Type::getVoidTy(C), {});
auto *F = cast<Function>(M.getOrInsertFunction("f", FTy));
auto *BB = BasicBlock::Create(C, "entry", F);
auto *IntType = Type::getInt32Ty(C);
auto *PtrType = Type::getInt32PtrTy(C);
auto *SI = new StoreInst(ConstantInt::get(IntType, 42),
ConstantPointerNull::get(PtrType), BB);
ReturnInst::Create(C, nullptr, BB);
auto *RootMD = MD.createTBAARoot("Simple C/C++ TBAA");
auto *MD1 = MD.createTBAANode("omnipotent char", RootMD);
auto *MD2 = MD.createTBAANode("int", MD1);
SI->setMetadata(LLVMContext::MD_tbaa, MD2);
SmallVector<char, 0> ErrorMsg;
raw_svector_ostream Outs(ErrorMsg);
StringRef ExpectedFailureMsg(
"Old-style TBAA is no longer allowed, use struct-path TBAA instead");
EXPECT_TRUE(verifyFunction(*F, &Outs));
EXPECT_TRUE(StringRef(ErrorMsg.begin(), ErrorMsg.size())
.startswith(ExpectedFailureMsg));
}
} // end anonymous namspace
} // end llvm namespace