xref: /freebsd/contrib/llvm-project/llvm/lib/Analysis/ValueLatticeUtils.cpp (revision 580744621f33383027108364dcadad718df46ffe)
1 //===-- ValueLatticeUtils.cpp - Utils for solving lattices ------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file implements common functions useful for performing data-flow
10 // analyses that propagate values across function boundaries.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/Analysis/ValueLatticeUtils.h"
15 #include "llvm/IR/GlobalVariable.h"
16 #include "llvm/IR/Instructions.h"
17 using namespace llvm;
18 
19 bool llvm::canTrackArgumentsInterprocedurally(Function *F) {
20   return F->hasLocalLinkage() && !F->hasAddressTaken();
21 }
22 
23 bool llvm::canTrackReturnsInterprocedurally(Function *F) {
24   return F->hasExactDefinition() && !F->hasFnAttribute(Attribute::Naked);
25 }
26 
27 bool llvm::canTrackGlobalVariableInterprocedurally(GlobalVariable *GV) {
28   if (GV->isConstant() || !GV->hasLocalLinkage() ||
29       !GV->hasDefinitiveInitializer())
30     return false;
31   return !any_of(GV->users(), [&](User *U) {
32     if (auto *Store = dyn_cast<StoreInst>(U)) {
33       if (Store->getValueOperand() == GV || Store->isVolatile())
34         return true;
35     } else if (auto *Load = dyn_cast<LoadInst>(U)) {
36       if (Load->isVolatile())
37         return true;
38     } else {
39       return true;
40     }
41     return false;
42   });
43 }
44