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https://github.com/c64scene-ar/llvm-6502.git
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0b8c9a80f2
into their new header subdirectory: include/llvm/IR. This matches the directory structure of lib, and begins to correct a long standing point of file layout clutter in LLVM. There are still more header files to move here, but I wanted to handle them in separate commits to make tracking what files make sense at each layer easier. The only really questionable files here are the target intrinsic tablegen files. But that's a battle I'd rather not fight today. I've updated both CMake and Makefile build systems (I think, and my tests think, but I may have missed something). I've also re-sorted the includes throughout the project. I'll be committing updates to Clang, DragonEgg, and Polly momentarily. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171366 91177308-0d34-0410-b5e6-96231b3b80d8
101 lines
4.0 KiB
C++
101 lines
4.0 KiB
C++
//===------ SimplifyInstructions.cpp - Remove redundant instructions ------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This is a utility pass used for testing the InstructionSimplify analysis.
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// The analysis is applied to every instruction, and if it simplifies then the
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// instruction is replaced by the simplification. If you are looking for a pass
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// that performs serious instruction folding, use the instcombine pass instead.
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//
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//===----------------------------------------------------------------------===//
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#define DEBUG_TYPE "instsimplify"
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#include "llvm/Transforms/Scalar.h"
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#include "llvm/ADT/DepthFirstIterator.h"
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#include "llvm/ADT/SmallPtrSet.h"
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#include "llvm/ADT/Statistic.h"
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#include "llvm/Analysis/Dominators.h"
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#include "llvm/Analysis/InstructionSimplify.h"
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#include "llvm/IR/DataLayout.h"
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#include "llvm/IR/Function.h"
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#include "llvm/IR/Type.h"
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#include "llvm/Pass.h"
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#include "llvm/Target/TargetLibraryInfo.h"
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#include "llvm/Transforms/Utils/Local.h"
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using namespace llvm;
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STATISTIC(NumSimplified, "Number of redundant instructions removed");
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namespace {
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struct InstSimplifier : public FunctionPass {
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static char ID; // Pass identification, replacement for typeid
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InstSimplifier() : FunctionPass(ID) {
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initializeInstSimplifierPass(*PassRegistry::getPassRegistry());
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}
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void getAnalysisUsage(AnalysisUsage &AU) const {
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AU.setPreservesCFG();
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AU.addRequired<TargetLibraryInfo>();
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}
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/// runOnFunction - Remove instructions that simplify.
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bool runOnFunction(Function &F) {
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const DominatorTree *DT = getAnalysisIfAvailable<DominatorTree>();
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const DataLayout *TD = getAnalysisIfAvailable<DataLayout>();
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const TargetLibraryInfo *TLI = &getAnalysis<TargetLibraryInfo>();
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SmallPtrSet<const Instruction*, 8> S1, S2, *ToSimplify = &S1, *Next = &S2;
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bool Changed = false;
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do {
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for (df_iterator<BasicBlock*> DI = df_begin(&F.getEntryBlock()),
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DE = df_end(&F.getEntryBlock()); DI != DE; ++DI)
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for (BasicBlock::iterator BI = DI->begin(), BE = DI->end(); BI != BE;) {
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Instruction *I = BI++;
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// The first time through the loop ToSimplify is empty and we try to
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// simplify all instructions. On later iterations ToSimplify is not
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// empty and we only bother simplifying instructions that are in it.
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if (!ToSimplify->empty() && !ToSimplify->count(I))
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continue;
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// Don't waste time simplifying unused instructions.
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if (!I->use_empty())
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if (Value *V = SimplifyInstruction(I, TD, TLI, DT)) {
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// Mark all uses for resimplification next time round the loop.
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for (Value::use_iterator UI = I->use_begin(), UE = I->use_end();
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UI != UE; ++UI)
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Next->insert(cast<Instruction>(*UI));
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I->replaceAllUsesWith(V);
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++NumSimplified;
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Changed = true;
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}
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Changed |= RecursivelyDeleteTriviallyDeadInstructions(I, TLI);
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}
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// Place the list of instructions to simplify on the next loop iteration
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// into ToSimplify.
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std::swap(ToSimplify, Next);
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Next->clear();
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} while (!ToSimplify->empty());
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return Changed;
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}
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};
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}
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char InstSimplifier::ID = 0;
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INITIALIZE_PASS_BEGIN(InstSimplifier, "instsimplify",
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"Remove redundant instructions", false, false)
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INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfo)
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INITIALIZE_PASS_END(InstSimplifier, "instsimplify",
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"Remove redundant instructions", false, false)
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char &llvm::InstructionSimplifierID = InstSimplifier::ID;
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// Public interface to the simplify instructions pass.
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FunctionPass *llvm::createInstructionSimplifierPass() {
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return new InstSimplifier();
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}
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