llvm-project/polly/lib/Transform/CodePreparation.cpp

100 lines
3.0 KiB
C++

//===---- CodePreparation.cpp - Code preparation for Scop Detection -------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// The Polly code preparation pass is executed before SCoP detection. Its
// currently only splits the entry block of the SCoP to make room for alloc
// instructions as they are generated during code generation.
//
// XXX: In the future, we should remove the need for this pass entirely and
// instead add this spitting to the code generation pass.
//
//===----------------------------------------------------------------------===//
#include "polly/LinkAllPasses.h"
#include "polly/CodeGen/BlockGenerators.h"
#include "polly/ScopDetection.h"
#include "polly/Support/ScopHelper.h"
#include "llvm/Analysis/DominanceFrontier.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/RegionInfo.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Transforms/Utils/Local.h"
using namespace llvm;
using namespace polly;
namespace {
/// @brief Prepare the IR for the scop detection.
///
class CodePreparation : public FunctionPass {
CodePreparation(const CodePreparation &) = delete;
const CodePreparation &operator=(const CodePreparation &) = delete;
LoopInfo *LI;
ScalarEvolution *SE;
void clear();
bool eliminatePHINodes(Function &F);
public:
static char ID;
explicit CodePreparation() : FunctionPass(ID) {}
~CodePreparation();
/// @name FunctionPass interface.
//@{
virtual void getAnalysisUsage(AnalysisUsage &AU) const;
virtual void releaseMemory();
virtual bool runOnFunction(Function &F);
virtual void print(raw_ostream &OS, const Module *) const;
//@}
};
}
void CodePreparation::clear() {}
CodePreparation::~CodePreparation() { clear(); }
void CodePreparation::getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequired<LoopInfoWrapperPass>();
AU.addRequired<ScalarEvolution>();
AU.addPreserved<LoopInfoWrapperPass>();
AU.addPreserved<RegionInfoPass>();
AU.addPreserved<DominatorTreeWrapperPass>();
AU.addPreserved<DominanceFrontier>();
}
bool CodePreparation::runOnFunction(Function &F) {
LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
SE = &getAnalysis<ScalarEvolution>();
splitEntryBlockForAlloca(&F.getEntryBlock(), this);
return false;
}
void CodePreparation::releaseMemory() { clear(); }
void CodePreparation::print(raw_ostream &OS, const Module *) const {}
char CodePreparation::ID = 0;
char &polly::CodePreparationID = CodePreparation::ID;
Pass *polly::createCodePreparationPass() { return new CodePreparation(); }
INITIALIZE_PASS_BEGIN(CodePreparation, "polly-prepare",
"Polly - Prepare code for polly", false, false)
INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)
INITIALIZE_PASS_END(CodePreparation, "polly-prepare",
"Polly - Prepare code for polly", false, false)