llvm-for-llvmta/lib/Analysis/ValueLatticeUtils.cpp

42 lines
1.5 KiB
C++

//===-- ValueLatticeUtils.cpp - Utils for solving lattices ------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file implements common functions useful for performing data-flow
// analyses that propagate values across function boundaries.
//
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/ValueLatticeUtils.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Instructions.h"
using namespace llvm;
bool llvm::canTrackArgumentsInterprocedurally(Function *F) {
return F->hasLocalLinkage() && !F->hasAddressTaken();
}
bool llvm::canTrackReturnsInterprocedurally(Function *F) {
return F->hasExactDefinition() && !F->hasFnAttribute(Attribute::Naked);
}
bool llvm::canTrackGlobalVariableInterprocedurally(GlobalVariable *GV) {
if (GV->isConstant() || !GV->hasLocalLinkage() ||
!GV->hasDefinitiveInitializer())
return false;
return all_of(GV->users(), [&](User *U) {
// Currently all users of a global variable have to be none-volatile loads
// or stores and the global cannot be stored itself.
if (auto *Store = dyn_cast<StoreInst>(U))
return Store->getValueOperand() != GV && !Store->isVolatile();
if (auto *Load = dyn_cast<LoadInst>(U))
return !Load->isVolatile();
return false;
});
}