diff options
Diffstat (limited to 'tools/gccas/gccas.cpp')
| -rw-r--r-- | tools/gccas/gccas.cpp | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/tools/gccas/gccas.cpp b/tools/gccas/gccas.cpp new file mode 100644 index 0000000000..2791cf4df2 --- /dev/null +++ b/tools/gccas/gccas.cpp @@ -0,0 +1,218 @@ +//===-- gccas.cpp - The "optimizing assembler" used by the GCC frontend ---===// +// +// The LLVM Compiler Infrastructure +// +// This file was developed by the LLVM research group and is distributed under +// the University of Illinois Open Source License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This utility is designed to be used by the GCC frontend for creating bytecode +// files from its intermediate LLVM assembly. The requirements for this utility +// are thus slightly different than that of the standard `as' util. +// +//===----------------------------------------------------------------------===// + +#include "llvm/Module.h" +#include "llvm/PassManager.h" +#include "llvm/Analysis/LoadValueNumbering.h" +#include "llvm/Analysis/Verifier.h" +#include "llvm/Assembly/Parser.h" +#include "llvm/Bytecode/WriteBytecodePass.h" +#include "llvm/Target/TargetData.h" +#include "llvm/Transforms/IPO.h" +#include "llvm/Transforms/Scalar.h" +#include "llvm/Support/CommandLine.h" +#include "llvm/System/Signals.h" +#include <memory> +#include <fstream> + +using namespace llvm; + +namespace { + cl::opt<std::string> + InputFilename(cl::Positional,cl::desc("<input llvm assembly>"),cl::init("-")); + + cl::opt<std::string> + OutputFilename("o", cl::desc("Override output filename"), + cl::value_desc("filename")); + + cl::opt<bool> + Verify("verify", cl::desc("Verify each pass result")); + + cl::opt<bool> + DisableInline("disable-inlining", cl::desc("Do not run the inliner pass")); + + cl::opt<bool> + DisableOptimizations("disable-opt", + cl::desc("Do not run any optimization passes")); + + cl::opt<bool> + StripDebug("strip-debug", + cl::desc("Strip debugger symbol info from translation unit")); + + cl::opt<bool> + NoCompress("disable-compression", cl::init(false), + cl::desc("Don't compress the generated bytecode")); + + cl::opt<bool> TF("traditional-format", cl::Hidden, + cl::desc("Compatibility option: ignored")); +} + + +static 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 (Verify) PM.add(createVerifierPass()); +} + + +void AddConfiguredTransformationPasses(PassManager &PM) { + PM.add(createVerifierPass()); // Verify that input is correct + + addPass(PM, createLowerSetJmpPass()); // Lower llvm.setjmp/.longjmp + addPass(PM, createFunctionResolvingPass()); // Resolve (...) functions + + // 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 + + if (!DisableInline) + addPass(PM, createFunctionInliningPass()); // Inline small functions + addPass(PM, createSimplifyLibCallsPass()); // Library Call Optimizations + addPass(PM, createArgumentPromotionPass()); // Scalarize uninlined fn args + + addPass(PM, createRaisePointerReferencesPass());// Recover type information + addPass(PM, createTailDuplicationPass()); // Simplify cfg by copying code + 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, createLICMPass()); // Hoist loop invariants + addPass(PM, createInstructionCombiningPass()); // Clean up after LICM/reassoc + addPass(PM, createIndVarSimplifyPass()); // Canonicalize indvars + addPass(PM, createLoopUnrollPass()); // Unroll small loops + addPass(PM, createInstructionCombiningPass()); // Clean up after the unroller + addPass(PM, createLoadValueNumberingPass()); // GVN for load instructions + addPass(PM, createGCSEPass()); // Remove common subexprs + 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()); // SSA based 'Aggressive DCE' + addPass(PM, createCFGSimplificationPass()); // Merge & remove BBs + addPass(PM, createDeadTypeEliminationPass()); // Eliminate dead types + addPass(PM, createConstantMergePass()); // Merge dup global constants +} + + +int main(int argc, char **argv) { + try { + cl::ParseCommandLineOptions(argc, argv, + " llvm .s -> .o assembler for GCC\n"); + sys::PrintStackTraceOnErrorSignal(); + + std::auto_ptr<Module> M; + try { + // Parse the file now... + M.reset(ParseAssemblyFile(InputFilename)); + } catch (const ParseException &E) { + std::cerr << argv[0] << ": " << E.getMessage() << "\n"; + return 1; + } + + if (M.get() == 0) { + std::cerr << argv[0] << ": assembly didn't read correctly.\n"; + return 1; + } + + std::ostream *Out = 0; + if (OutputFilename == "") { // Didn't specify an output filename? + if (InputFilename == "-") { + OutputFilename = "-"; + } else { + std::string IFN = InputFilename; + int Len = IFN.length(); + if (IFN[Len-2] == '.' && IFN[Len-1] == 's') { // Source ends in .s? + OutputFilename = std::string(IFN.begin(), IFN.end()-2); + } else { + OutputFilename = IFN; // Append a .o to it + } + OutputFilename += ".o"; + } + } + + if (OutputFilename == "-") + // FIXME: cout is not binary! + Out = &std::cout; + else { + std::ios::openmode io_mode = std::ios::out | std::ios::trunc | + std::ios::binary; + Out = new std::ofstream(OutputFilename.c_str(), io_mode); + + // Make sure that the Out file gets unlinked from the disk if we get a + // signal + sys::RemoveFileOnSignal(sys::Path(OutputFilename)); + } + + + if (!Out->good()) { + std::cerr << argv[0] << ": error opening " << OutputFilename << "!\n"; + return 1; + } + + // In addition to just parsing the input from GCC, we also want to spiff it up + // a little bit. Do this now. + // + PassManager Passes; + + // Add an appropriate TargetData instance for this module... + Passes.add(new TargetData("gccas", M.get())); + + // Add all of the transformation passes to the pass manager to do the cleanup + // and optimization of the GCC output. + // + AddConfiguredTransformationPasses(Passes); + + // Make sure everything is still good. + Passes.add(createVerifierPass()); + + // Write bytecode to file... + Passes.add(new WriteBytecodePass(Out,false,!NoCompress)); + + // Run our queue of passes all at once now, efficiently. + Passes.run(*M.get()); + + if (Out != &std::cout) delete Out; + return 0; + } catch (const std::string& msg) { + std::cerr << argv[0] << ": " << msg << "\n"; + } catch (...) { + std::cerr << argv[0] << ": Unexpected unknown exception occurred.\n"; + } + return 1; +} |