//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "globalsmodref-aa"
#include "llvm/Analysis/Passes.h"
#include "llvm/ADT/SCCIterator.h"
#include "llvm/ADT/Statistic.h"
#include <set>
using namespace llvm;
+#define DEBUG_TYPE "globalsmodref-aa"
+
STATISTIC(NumNonAddrTakenGlobalVars,
"Number of global vars without address taken");
STATISTIC(NumNonAddrTakenFunctions,"Number of functions without address taken");
FunctionInfo.find(F);
if (I != FunctionInfo.end())
return &I->second;
- return 0;
+ return nullptr;
}
void AnalyzeGlobals(Module &M);
void AnalyzeCallGraph(CallGraph &CG, Module &M);
bool AnalyzeUsesOfPointer(Value *V, std::vector<Function*> &Readers,
std::vector<Function*> &Writers,
- GlobalValue *OkayStoreDest = 0);
+ GlobalValue *OkayStoreDest = nullptr);
bool AnalyzeIndirectGlobalMemory(GlobalValue *GV);
};
}
GlobalValue *OkayStoreDest) {
if (!V->getType()->isPointerTy()) return true;
- for (Value::use_iterator UI = V->use_begin(), E=V->use_end(); UI != E; ++UI) {
- User *U = *UI;
- if (LoadInst *LI = dyn_cast<LoadInst>(U)) {
+ for (Use &U : V->uses()) {
+ User *I = U.getUser();
+ if (LoadInst *LI = dyn_cast<LoadInst>(I)) {
Readers.push_back(LI->getParent()->getParent());
- } else if (StoreInst *SI = dyn_cast<StoreInst>(U)) {
+ } else if (StoreInst *SI = dyn_cast<StoreInst>(I)) {
if (V == SI->getOperand(1)) {
Writers.push_back(SI->getParent()->getParent());
} else if (SI->getOperand(1) != OkayStoreDest) {
return true; // Storing the pointer
}
- } else if (Operator::getOpcode(U) == Instruction::GetElementPtr) {
- if (AnalyzeUsesOfPointer(U, Readers, Writers))
+ } else if (Operator::getOpcode(I) == Instruction::GetElementPtr) {
+ if (AnalyzeUsesOfPointer(I, Readers, Writers))
return true;
- } else if (Operator::getOpcode(U) == Instruction::BitCast) {
- if (AnalyzeUsesOfPointer(U, Readers, Writers, OkayStoreDest))
+ } else if (Operator::getOpcode(I) == Instruction::BitCast) {
+ if (AnalyzeUsesOfPointer(I, Readers, Writers, OkayStoreDest))
return true;
- } else if (CallSite CS = U) {
+ } else if (CallSite CS = I) {
// Make sure that this is just the function being called, not that it is
// passing into the function.
- if (!CS.isCallee(UI)) {
+ if (!CS.isCallee(&U)) {
// Detect calls to free.
- if (isFreeCall(U, TLI))
+ if (isFreeCall(I, TLI))
Writers.push_back(CS->getParent()->getParent());
else
return true; // Argument of an unknown call.
}
- } else if (ICmpInst *ICI = dyn_cast<ICmpInst>(U)) {
+ } else if (ICmpInst *ICI = dyn_cast<ICmpInst>(I)) {
if (!isa<ConstantPointerNull>(ICI->getOperand(1)))
return true; // Allow comparison against null.
} else {
// Walk the user list of the global. If we find anything other than a direct
// load or store, bail out.
- for (Value::use_iterator I = GV->use_begin(), E = GV->use_end(); I != E; ++I){
- User *U = *I;
+ for (User *U : GV->users()) {
if (LoadInst *LI = dyn_cast<LoadInst>(U)) {
// The pointer loaded from the global can only be used in simple ways:
// we allow addressing of it and loading storing to it. We do *not* allow
// We do a bottom-up SCC traversal of the call graph. In other words, we
// visit all callees before callers (leaf-first).
for (scc_iterator<CallGraph*> I = scc_begin(&CG); !I.isAtEnd(); ++I) {
- std::vector<CallGraphNode *> &SCC = *I;
+ const std::vector<CallGraphNode *> &SCC = *I;
assert(!SCC.empty() && "SCC with no functions?");
if (!SCC[0]->getFunction()) {
FunctionEffect |= CalleeFR->FunctionEffect;
// Incorporate callee's effects on globals into our info.
- for (std::map<const GlobalValue*, unsigned>::iterator GI =
- CalleeFR->GlobalInfo.begin(), E = CalleeFR->GlobalInfo.end();
- GI != E; ++GI)
- FR.GlobalInfo[GI->first] |= GI->second;
+ for (const auto &G : CalleeFR->GlobalInfo)
+ FR.GlobalInfo[G.first] |= G.second;
FR.MayReadAnyGlobal |= CalleeFR->MayReadAnyGlobal;
} else {
// Can't say anything about it. However, if it is inside our SCC,
if (GV1 || GV2) {
// If the global's address is taken, pretend we don't know it's a pointer to
// the global.
- if (GV1 && !NonAddressTakenGlobals.count(GV1)) GV1 = 0;
- if (GV2 && !NonAddressTakenGlobals.count(GV2)) GV2 = 0;
+ if (GV1 && !NonAddressTakenGlobals.count(GV1)) GV1 = nullptr;
+ if (GV2 && !NonAddressTakenGlobals.count(GV2)) GV2 = nullptr;
// If the two pointers are derived from two different non-addr-taken
// globals, or if one is and the other isn't, we know these can't alias.
// These pointers may be based on the memory owned by an indirect global. If
// so, we may be able to handle this. First check to see if the base pointer
// is a direct load from an indirect global.
- GV1 = GV2 = 0;
+ GV1 = GV2 = nullptr;
if (const LoadInst *LI = dyn_cast<LoadInst>(UV1))
if (GlobalVariable *GV = dyn_cast<GlobalVariable>(LI->getOperand(0)))
if (IndirectGlobals.count(GV))