llvm/lib/Transforms/Utils/Mem2Reg.cpp
Dan Gohman 844731a7f1 Clean up the use of static and anonymous namespaces. This turned up
several things that were neither in an anonymous namespace nor static
but not intended to be global.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51017 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-13 00:00:25 +00:00

93 lines
3.0 KiB
C++

//===- Mem2Reg.cpp - The -mem2reg pass, a wrapper around the Utils lib ----===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This pass is a simple pass wrapper around the PromoteMemToReg function call
// exposed by the Utils library.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "mem2reg"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Utils/PromoteMemToReg.h"
#include "llvm/Transforms/Utils/UnifyFunctionExitNodes.h"
#include "llvm/Analysis/Dominators.h"
#include "llvm/Instructions.h"
#include "llvm/Function.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Support/Compiler.h"
using namespace llvm;
STATISTIC(NumPromoted, "Number of alloca's promoted");
namespace {
struct VISIBILITY_HIDDEN PromotePass : public FunctionPass {
static char ID; // Pass identification, replacement for typeid
PromotePass() : FunctionPass((intptr_t)&ID) {}
// runOnFunction - To run this pass, first we calculate the alloca
// instructions that are safe for promotion, then we promote each one.
//
virtual bool runOnFunction(Function &F);
// getAnalysisUsage - We need dominance frontiers
//
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequired<DominatorTree>();
AU.addRequired<DominanceFrontier>();
AU.setPreservesCFG();
// This is a cluster of orthogonal Transforms
AU.addPreserved<UnifyFunctionExitNodes>();
AU.addPreservedID(LowerSwitchID);
AU.addPreservedID(LowerInvokePassID);
AU.addPreservedID(LowerAllocationsID);
}
};
} // end of anonymous namespace
char PromotePass::ID = 0;
static RegisterPass<PromotePass> X("mem2reg", "Promote Memory to Register");
bool PromotePass::runOnFunction(Function &F) {
std::vector<AllocaInst*> Allocas;
BasicBlock &BB = F.getEntryBlock(); // Get the entry node for the function
bool Changed = false;
DominatorTree &DT = getAnalysis<DominatorTree>();
DominanceFrontier &DF = getAnalysis<DominanceFrontier>();
while (1) {
Allocas.clear();
// Find allocas that are safe to promote, by looking at all instructions in
// the entry node
for (BasicBlock::iterator I = BB.begin(), E = --BB.end(); I != E; ++I)
if (AllocaInst *AI = dyn_cast<AllocaInst>(I)) // Is it an alloca?
if (isAllocaPromotable(AI))
Allocas.push_back(AI);
if (Allocas.empty()) break;
PromoteMemToReg(Allocas, DT, DF);
NumPromoted += Allocas.size();
Changed = true;
}
return Changed;
}
// Publically exposed interface to pass...
const PassInfo *llvm::PromoteMemoryToRegisterID = X.getPassInfo();
// createPromoteMemoryToRegister - Provide an entry point to create this pass.
//
FunctionPass *llvm::createPromoteMemoryToRegisterPass() {
return new PromotePass();
}