llvm-6502/tools/opt/opt.cpp
Duncan Sands 9e89ba31f1 Rename AddReadAttrs to FunctionAttrs, and teach it how
to work out (in a very simplistic way) which function
arguments (pointer arguments only) are only dereferenced
and so do not escape.  Mark such arguments 'nocapture'.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61525 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-31 16:14:43 +00:00

603 lines
22 KiB
C++

//===- opt.cpp - The LLVM Modular Optimizer -------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Optimizations may be specified an arbitrary number of times on the command
// line, They are run in the order specified.
//
//===----------------------------------------------------------------------===//
#include "llvm/Module.h"
#include "llvm/ModuleProvider.h"
#include "llvm/PassManager.h"
#include "llvm/CallGraphSCCPass.h"
#include "llvm/Bitcode/ReaderWriter.h"
#include "llvm/Assembly/PrintModulePass.h"
#include "llvm/Analysis/Verifier.h"
#include "llvm/Analysis/LoopPass.h"
#include "llvm/Analysis/CallGraph.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Support/PassNameParser.h"
#include "llvm/System/Signals.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/PluginLoader.h"
#include "llvm/Support/Streams.h"
#include "llvm/Support/SystemUtils.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/LinkAllPasses.h"
#include "llvm/LinkAllVMCore.h"
#include <iostream>
#include <fstream>
#include <memory>
#include <algorithm>
using namespace llvm;
// The OptimizationList is automatically populated with registered Passes by the
// PassNameParser.
//
static cl::list<const PassInfo*, bool, PassNameParser>
PassList(cl::desc("Optimizations available:"));
// Other command line options...
//
static cl::opt<std::string>
InputFilename(cl::Positional, cl::desc("<input bitcode file>"),
cl::init("-"), cl::value_desc("filename"));
static cl::opt<std::string>
OutputFilename("o", cl::desc("Override output filename"),
cl::value_desc("filename"), cl::init("-"));
static cl::opt<bool>
Force("f", cl::desc("Overwrite output files"));
static cl::opt<bool>
PrintEachXForm("p", cl::desc("Print module after each transformation"));
static cl::opt<bool>
NoOutput("disable-output",
cl::desc("Do not write result bitcode file"), cl::Hidden);
static cl::opt<bool>
NoVerify("disable-verify", cl::desc("Do not verify result module"), cl::Hidden);
static cl::opt<bool>
VerifyEach("verify-each", cl::desc("Verify after each transform"));
static cl::opt<bool>
StripDebug("strip-debug",
cl::desc("Strip debugger symbol info from translation unit"));
static cl::opt<bool>
DisableInline("disable-inlining", cl::desc("Do not run the inliner pass"));
static cl::opt<bool>
DisableOptimizations("disable-opt",
cl::desc("Do not run any optimization passes"));
static cl::opt<bool>
StandardCompileOpts("std-compile-opts",
cl::desc("Include the standard compile time optimizations"));
static cl::opt<bool>
OptLevelO1("O1",
cl::desc("Optimization level 1. Similar to llvm-gcc -O1"));
static cl::opt<bool>
OptLevelO2("O2",
cl::desc("Optimization level 2. Similar to llvm-gcc -O2"));
static cl::opt<bool>
OptLevelO3("O3",
cl::desc("Optimization level 3. Similar to llvm-gcc -O3"));
static cl::opt<bool>
UnitAtATime("funit-at-a-time",
cl::desc("Enable IPO. This is same as llvm-gcc's -funit-at-a-time"));
static cl::opt<bool>
DisableSimplifyLibCalls("disable-simplify-libcalls",
cl::desc("Disable simplify-libcalls"));
static cl::opt<bool>
Quiet("q", cl::desc("Obsolete option"), cl::Hidden);
static cl::alias
QuietA("quiet", cl::desc("Alias for -q"), cl::aliasopt(Quiet));
static cl::opt<bool>
AnalyzeOnly("analyze", cl::desc("Only perform analysis, no optimization"));
// ---------- Define Printers for module and function passes ------------
namespace {
struct CallGraphSCCPassPrinter : public CallGraphSCCPass {
static char ID;
const PassInfo *PassToPrint;
CallGraphSCCPassPrinter(const PassInfo *PI) :
CallGraphSCCPass((intptr_t)&ID), PassToPrint(PI) {}
virtual bool runOnSCC(const std::vector<CallGraphNode *>&SCC) {
if (!Quiet) {
cout << "Printing analysis '" << PassToPrint->getPassName() << "':\n";
for (unsigned i = 0, e = SCC.size(); i != e; ++i) {
Function *F = SCC[i]->getFunction();
if (F)
getAnalysisID<Pass>(PassToPrint).print(cout, F->getParent());
}
}
// Get and print pass...
return false;
}
virtual const char *getPassName() const { return "'Pass' Printer"; }
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequiredID(PassToPrint);
AU.setPreservesAll();
}
};
char CallGraphSCCPassPrinter::ID = 0;
struct ModulePassPrinter : public ModulePass {
static char ID;
const PassInfo *PassToPrint;
ModulePassPrinter(const PassInfo *PI) : ModulePass((intptr_t)&ID),
PassToPrint(PI) {}
virtual bool runOnModule(Module &M) {
if (!Quiet) {
cout << "Printing analysis '" << PassToPrint->getPassName() << "':\n";
getAnalysisID<Pass>(PassToPrint).print(cout, &M);
}
// Get and print pass...
return false;
}
virtual const char *getPassName() const { return "'Pass' Printer"; }
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequiredID(PassToPrint);
AU.setPreservesAll();
}
};
char ModulePassPrinter::ID = 0;
struct FunctionPassPrinter : public FunctionPass {
const PassInfo *PassToPrint;
static char ID;
FunctionPassPrinter(const PassInfo *PI) : FunctionPass((intptr_t)&ID),
PassToPrint(PI) {}
virtual bool runOnFunction(Function &F) {
if (!Quiet) {
cout << "Printing analysis '" << PassToPrint->getPassName()
<< "' for function '" << F.getName() << "':\n";
}
// Get and print pass...
getAnalysisID<Pass>(PassToPrint).print(cout, F.getParent());
return false;
}
virtual const char *getPassName() const { return "FunctionPass Printer"; }
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequiredID(PassToPrint);
AU.setPreservesAll();
}
};
char FunctionPassPrinter::ID = 0;
struct LoopPassPrinter : public LoopPass {
static char ID;
const PassInfo *PassToPrint;
LoopPassPrinter(const PassInfo *PI) :
LoopPass((intptr_t)&ID), PassToPrint(PI) {}
virtual bool runOnLoop(Loop *L, LPPassManager &LPM) {
if (!Quiet) {
cout << "Printing analysis '" << PassToPrint->getPassName() << "':\n";
getAnalysisID<Pass>(PassToPrint).print(cout,
L->getHeader()->getParent()->getParent());
}
// Get and print pass...
return false;
}
virtual const char *getPassName() const { return "'Pass' Printer"; }
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequiredID(PassToPrint);
AU.setPreservesAll();
}
};
char LoopPassPrinter::ID = 0;
struct BasicBlockPassPrinter : public BasicBlockPass {
const PassInfo *PassToPrint;
static char ID;
BasicBlockPassPrinter(const PassInfo *PI)
: BasicBlockPass((intptr_t)&ID), PassToPrint(PI) {}
virtual bool runOnBasicBlock(BasicBlock &BB) {
if (!Quiet) {
cout << "Printing Analysis info for BasicBlock '" << BB.getName()
<< "': Pass " << PassToPrint->getPassName() << ":\n";
}
// Get and print pass...
getAnalysisID<Pass>(PassToPrint).print(cout, BB.getParent()->getParent());
return false;
}
virtual const char *getPassName() const { return "BasicBlockPass Printer"; }
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequiredID(PassToPrint);
AU.setPreservesAll();
}
};
char BasicBlockPassPrinter::ID = 0;
inline void addPass(PassManager &PM, Pass *P) {
// Add the pass to the pass manager...
PM.add(P);
// If we are verifying all of the intermediate steps, add the verifier...
if (VerifyEach) PM.add(createVerifierPass());
}
/// AddOptimizationPasses - This routine adds optimization passes
/// based on selected optimization level, OptLevel. This routine
/// duplicates llvm-gcc behaviour.
///
/// OptLevel - Optimization Level
void AddOptimizationPasses(PassManager &MPM, FunctionPassManager &FPM,
unsigned OptLevel) {
if (OptLevel == 0)
return;
FPM.add(createCFGSimplificationPass());
if (OptLevel == 1)
FPM.add(createPromoteMemoryToRegisterPass());
else
FPM.add(createScalarReplAggregatesPass());
FPM.add(createInstructionCombiningPass());
if (UnitAtATime)
MPM.add(createRaiseAllocationsPass()); // call %malloc -> malloc inst
MPM.add(createCFGSimplificationPass()); // Clean up disgusting code
MPM.add(createPromoteMemoryToRegisterPass()); // Kill useless allocas
if (UnitAtATime) {
MPM.add(createGlobalOptimizerPass()); // OptLevel out global vars
MPM.add(createGlobalDCEPass()); // Remove unused fns and globs
MPM.add(createIPConstantPropagationPass()); // IP Constant Propagation
MPM.add(createDeadArgEliminationPass()); // Dead argument elimination
}
MPM.add(createInstructionCombiningPass()); // Clean up after IPCP & DAE
MPM.add(createCFGSimplificationPass()); // Clean up after IPCP & DAE
if (UnitAtATime) {
MPM.add(createPruneEHPass()); // Remove dead EH info
MPM.add(createFunctionAttrsPass()); // Deduce function attrs
}
if (OptLevel > 1)
MPM.add(createFunctionInliningPass()); // Inline small functions
if (OptLevel > 2)
MPM.add(createArgumentPromotionPass()); // Scalarize uninlined fn args
if (!DisableSimplifyLibCalls)
MPM.add(createSimplifyLibCallsPass()); // Library Call Optimizations
MPM.add(createInstructionCombiningPass()); // Cleanup for scalarrepl.
MPM.add(createJumpThreadingPass()); // Thread jumps.
MPM.add(createCFGSimplificationPass()); // Merge & remove BBs
MPM.add(createScalarReplAggregatesPass()); // Break up aggregate allocas
MPM.add(createInstructionCombiningPass()); // Combine silly seq's
MPM.add(createCondPropagationPass()); // Propagate conditionals
MPM.add(createTailCallEliminationPass()); // Eliminate tail calls
MPM.add(createCFGSimplificationPass()); // Merge & remove BBs
MPM.add(createReassociatePass()); // Reassociate expressions
MPM.add(createLoopRotatePass()); // Rotate Loop
MPM.add(createLICMPass()); // Hoist loop invariants
MPM.add(createLoopUnswitchPass());
MPM.add(createLoopIndexSplitPass()); // Split loop index
MPM.add(createInstructionCombiningPass());
MPM.add(createIndVarSimplifyPass()); // Canonicalize indvars
MPM.add(createLoopDeletionPass()); // Delete dead loops
if (OptLevel > 1)
MPM.add(createLoopUnrollPass()); // Unroll small loops
MPM.add(createInstructionCombiningPass()); // Clean up after the unroller
MPM.add(createGVNPass()); // Remove redundancies
MPM.add(createMemCpyOptPass()); // Remove memcpy / form memset
MPM.add(createSCCPPass()); // Constant prop with SCCP
// Run instcombine after redundancy elimination to exploit opportunities
// opened up by them.
MPM.add(createInstructionCombiningPass());
MPM.add(createCondPropagationPass()); // Propagate conditionals
MPM.add(createDeadStoreEliminationPass()); // Delete dead stores
MPM.add(createAggressiveDCEPass()); // Delete dead instructions
MPM.add(createCFGSimplificationPass()); // Merge & remove BBs
if (UnitAtATime) {
MPM.add(createStripDeadPrototypesPass()); // Get rid of dead prototypes
MPM.add(createDeadTypeEliminationPass()); // Eliminate dead types
}
if (OptLevel > 1 && UnitAtATime)
MPM.add(createConstantMergePass()); // Merge dup global constants
return;
}
void AddStandardCompilePasses(PassManager &PM) {
PM.add(createVerifierPass()); // Verify that input is correct
addPass(PM, createLowerSetJmpPass()); // Lower llvm.setjmp/.longjmp
// If the -strip-debug command line option was specified, do it.
if (StripDebug)
addPass(PM, createStripSymbolsPass(true));
if (DisableOptimizations) return;
addPass(PM, createRaiseAllocationsPass()); // call %malloc -> malloc inst
addPass(PM, createCFGSimplificationPass()); // Clean up disgusting code
addPass(PM, createPromoteMemoryToRegisterPass());// Kill useless allocas
addPass(PM, createGlobalOptimizerPass()); // Optimize out global vars
addPass(PM, createGlobalDCEPass()); // Remove unused fns and globs
addPass(PM, createIPConstantPropagationPass());// IP Constant Propagation
addPass(PM, createDeadArgEliminationPass()); // Dead argument elimination
addPass(PM, createInstructionCombiningPass()); // Clean up after IPCP & DAE
addPass(PM, createCFGSimplificationPass()); // Clean up after IPCP & DAE
addPass(PM, createPruneEHPass()); // Remove dead EH info
addPass(PM, createFunctionAttrsPass()); // Deduce function attrs
if (!DisableInline)
addPass(PM, createFunctionInliningPass()); // Inline small functions
addPass(PM, createArgumentPromotionPass()); // Scalarize uninlined fn args
addPass(PM, createSimplifyLibCallsPass()); // Library Call Optimizations
addPass(PM, createInstructionCombiningPass()); // Cleanup for scalarrepl.
addPass(PM, createJumpThreadingPass()); // Thread jumps.
addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
addPass(PM, createScalarReplAggregatesPass()); // Break up aggregate allocas
addPass(PM, createInstructionCombiningPass()); // Combine silly seq's
addPass(PM, createCondPropagationPass()); // Propagate conditionals
addPass(PM, createTailCallEliminationPass()); // Eliminate tail calls
addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
addPass(PM, createReassociatePass()); // Reassociate expressions
addPass(PM, createLoopRotatePass());
addPass(PM, createLICMPass()); // Hoist loop invariants
addPass(PM, createLoopUnswitchPass()); // Unswitch loops.
addPass(PM, createLoopIndexSplitPass()); // Index split loops.
// FIXME : Removing instcombine causes nestedloop regression.
addPass(PM, createInstructionCombiningPass());
addPass(PM, createIndVarSimplifyPass()); // Canonicalize indvars
addPass(PM, createLoopDeletionPass()); // Delete dead loops
addPass(PM, createLoopUnrollPass()); // Unroll small loops
addPass(PM, createInstructionCombiningPass()); // Clean up after the unroller
addPass(PM, createGVNPass()); // Remove redundancies
addPass(PM, createMemCpyOptPass()); // Remove memcpy / form memset
addPass(PM, createSCCPPass()); // Constant prop with SCCP
// Run instcombine after redundancy elimination to exploit opportunities
// opened up by them.
addPass(PM, createInstructionCombiningPass());
addPass(PM, createCondPropagationPass()); // Propagate conditionals
addPass(PM, createDeadStoreEliminationPass()); // Delete dead stores
addPass(PM, createAggressiveDCEPass()); // Delete dead instructions
addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs
addPass(PM, createStripDeadPrototypesPass()); // Get rid of dead prototypes
addPass(PM, createDeadTypeEliminationPass()); // Eliminate dead types
addPass(PM, createConstantMergePass()); // Merge dup global constants
}
} // anonymous namespace
//===----------------------------------------------------------------------===//
// main for opt
//
int main(int argc, char **argv) {
llvm_shutdown_obj X; // Call llvm_shutdown() on exit.
try {
cl::ParseCommandLineOptions(argc, argv,
"llvm .bc -> .bc modular optimizer and analysis printer\n");
sys::PrintStackTraceOnErrorSignal();
// Allocate a full target machine description only if necessary.
// FIXME: The choice of target should be controllable on the command line.
std::auto_ptr<TargetMachine> target;
std::string ErrorMessage;
// Load the input module...
std::auto_ptr<Module> M;
if (MemoryBuffer *Buffer
= MemoryBuffer::getFileOrSTDIN(InputFilename, &ErrorMessage)) {
M.reset(ParseBitcodeFile(Buffer, &ErrorMessage));
delete Buffer;
}
if (M.get() == 0) {
cerr << argv[0] << ": ";
if (ErrorMessage.size())
cerr << ErrorMessage << "\n";
else
cerr << "bitcode didn't read correctly.\n";
return 1;
}
// Figure out what stream we are supposed to write to...
// FIXME: cout is not binary!
std::ostream *Out = &std::cout; // Default to printing to stdout...
if (OutputFilename != "-") {
if (!Force && std::ifstream(OutputFilename.c_str())) {
// If force is not specified, make sure not to overwrite a file!
cerr << argv[0] << ": error opening '" << OutputFilename
<< "': file exists!\n"
<< "Use -f command line argument to force output\n";
return 1;
}
std::ios::openmode io_mode = std::ios::out | std::ios::trunc |
std::ios::binary;
Out = new std::ofstream(OutputFilename.c_str(), io_mode);
if (!Out->good()) {
cerr << argv[0] << ": error opening " << OutputFilename << "!\n";
return 1;
}
// Make sure that the Output file gets unlinked from the disk if we get a
// SIGINT
sys::RemoveFileOnSignal(sys::Path(OutputFilename));
}
// If the output is set to be emitted to standard out, and standard out is a
// console, print out a warning message and refuse to do it. We don't
// impress anyone by spewing tons of binary goo to a terminal.
if (!Force && !NoOutput && CheckBitcodeOutputToConsole(Out,!Quiet)) {
NoOutput = true;
}
// Create a PassManager to hold and optimize the collection of passes we are
// about to build...
//
PassManager Passes;
// Add an appropriate TargetData instance for this module...
Passes.add(new TargetData(M.get()));
FunctionPassManager *FPasses = NULL;
if (OptLevelO1 || OptLevelO2 || OptLevelO3) {
FPasses = new FunctionPassManager(new ExistingModuleProvider(M.get()));
FPasses->add(new TargetData(M.get()));
}
// If the -strip-debug command line option was specified, add it. If
// -std-compile-opts was also specified, it will handle StripDebug.
if (StripDebug && !StandardCompileOpts)
addPass(Passes, createStripSymbolsPass(true));
// Create a new optimization pass for each one specified on the command line
for (unsigned i = 0; i < PassList.size(); ++i) {
// Check to see if -std-compile-opts was specified before this option. If
// so, handle it.
if (StandardCompileOpts &&
StandardCompileOpts.getPosition() < PassList.getPosition(i)) {
AddStandardCompilePasses(Passes);
StandardCompileOpts = false;
}
if (OptLevelO1 && OptLevelO1.getPosition() < PassList.getPosition(i)) {
AddOptimizationPasses(Passes, *FPasses, 1);
OptLevelO1 = false;
}
if (OptLevelO2 && OptLevelO2.getPosition() < PassList.getPosition(i)) {
AddOptimizationPasses(Passes, *FPasses, 2);
OptLevelO2 = false;
}
if (OptLevelO3 && OptLevelO3.getPosition() < PassList.getPosition(i)) {
AddOptimizationPasses(Passes, *FPasses, 3);
OptLevelO3 = false;
}
const PassInfo *PassInf = PassList[i];
Pass *P = 0;
if (PassInf->getNormalCtor())
P = PassInf->getNormalCtor()();
else
cerr << argv[0] << ": cannot create pass: "
<< PassInf->getPassName() << "\n";
if (P) {
bool isBBPass = dynamic_cast<BasicBlockPass*>(P) != 0;
bool isLPass = !isBBPass && dynamic_cast<LoopPass*>(P) != 0;
bool isFPass = !isLPass && dynamic_cast<FunctionPass*>(P) != 0;
bool isCGSCCPass = !isFPass && dynamic_cast<CallGraphSCCPass*>(P) != 0;
addPass(Passes, P);
if (AnalyzeOnly) {
if (isBBPass)
Passes.add(new BasicBlockPassPrinter(PassInf));
else if (isLPass)
Passes.add(new LoopPassPrinter(PassInf));
else if (isFPass)
Passes.add(new FunctionPassPrinter(PassInf));
else if (isCGSCCPass)
Passes.add(new CallGraphSCCPassPrinter(PassInf));
else
Passes.add(new ModulePassPrinter(PassInf));
}
}
if (PrintEachXForm)
Passes.add(createPrintModulePass(&errs()));
}
// If -std-compile-opts was specified at the end of the pass list, add them.
if (StandardCompileOpts) {
AddStandardCompilePasses(Passes);
StandardCompileOpts = false;
}
if (OptLevelO1) {
AddOptimizationPasses(Passes, *FPasses, 1);
}
if (OptLevelO2) {
AddOptimizationPasses(Passes, *FPasses, 2);
}
if (OptLevelO3) {
AddOptimizationPasses(Passes, *FPasses, 3);
}
if (OptLevelO1 || OptLevelO2 || OptLevelO3) {
for (Module::iterator I = M.get()->begin(), E = M.get()->end();
I != E; ++I)
FPasses->run(*I);
}
// Check that the module is well formed on completion of optimization
if (!NoVerify && !VerifyEach)
Passes.add(createVerifierPass());
// Write bitcode out to disk or cout as the last step...
if (!NoOutput && !AnalyzeOnly)
Passes.add(CreateBitcodeWriterPass(*Out));
// Now that we have all of the passes ready, run them.
Passes.run(*M.get());
// Delete the ofstream.
if (Out != &std::cout)
delete Out;
return 0;
} catch (const std::string& msg) {
cerr << argv[0] << ": " << msg << "\n";
} catch (...) {
cerr << argv[0] << ": Unexpected unknown exception occurred.\n";
}
llvm_shutdown();
return 1;
}