llvm-mirror/unittests/Analysis/GlobalsModRefTest.cpp
David Blaikie 73b29ebe81 GlobalsModRef+OptNone: Don't prove readnone/other properties from an optnone function
Seems like at least one reasonable interpretation of optnone is that the
optimizer never "looks inside" a function. This fix is consistent with
that interpretation.

Specifically this came up in the situation:

f3 calls f2 calls f1
f2 is always_inline
f1 is optnone

The application of readnone to f1 (& thus to f2) caused the inliner to
kill the call to f2 as being trivially dead (without even checking the
cost function, as it happens - not sure if that's also a bug).

llvm-svn: 304833
2017-06-06 20:51:15 +00:00

42 lines
1.2 KiB
C++

//===--- GlobalsModRefTest.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/GlobalsModRef.h"
#include "llvm/AsmParser/Parser.h"
#include "llvm/Support/SourceMgr.h"
#include "gtest/gtest.h"
using namespace llvm;
TEST(GlobalsModRef, OptNone) {
StringRef Assembly = R"(
define void @f() optnone {
ret void
}
)";
LLVMContext Context;
SMDiagnostic Error;
auto M = parseAssemblyString(Assembly, Error, Context);
ASSERT_TRUE(M) << "Bad assembly?";
const auto &funcs = M->functions();
ASSERT_NE(funcs.begin(), funcs.end());
EXPECT_EQ(std::next(funcs.begin()), funcs.end());
const Function &F = *funcs.begin();
Triple Trip(M->getTargetTriple());
TargetLibraryInfoImpl TLII(Trip);
TargetLibraryInfo TLI(TLII);
llvm::CallGraph CG(*M);
auto AAR = GlobalsAAResult::analyzeModule(*M, TLI, CG);
EXPECT_EQ(FMRB_UnknownModRefBehavior, AAR.getModRefBehavior(&F));
}