1 //===----------------------------------------------------------------------===//
2 // LLVM 'GCCAS' UTILITY
4 // This utility is designed to be used by the GCC frontend for creating
5 // bytecode files from it's intermediate llvm assembly. The requirements for
6 // this utility are thus slightly different than that of the standard as util.
8 //===----------------------------------------------------------------------===//
10 #include "llvm/Module.h"
11 #include "llvm/PassManager.h"
12 #include "llvm/Assembly/Parser.h"
13 #include "llvm/Transforms/CleanupGCCOutput.h"
14 #include "llvm/Transforms/LevelChange.h"
15 #include "llvm/Transforms/ConstantMerge.h"
16 #include "llvm/Transforms/ChangeAllocations.h"
17 #include "llvm/Transforms/Scalar.h"
18 #include "llvm/Bytecode/WriteBytecodePass.h"
19 #include "Support/CommandLine.h"
20 #include "Support/Signals.h"
24 cl::String InputFilename ("", "Parse <arg> file, compile to bytecode",
26 cl::String OutputFilename("o", "Override output filename", cl::NoFlags, "");
27 cl::Flag StopAtLevelRaise("stopraise", "Stop optimization before level raise",
30 int main(int argc, char **argv) {
31 cl::ParseCommandLineOptions(argc, argv, " llvm .s -> .o assembler for GCC\n");
33 std::auto_ptr<Module> M;
35 // Parse the file now...
36 M.reset(ParseAssemblyFile(InputFilename));
37 } catch (const ParseException &E) {
38 cerr << E.getMessage() << endl;
43 cerr << "assembly didn't read correctly.\n";
47 if (OutputFilename == "") { // Didn't specify an output filename?
48 std::string IFN = InputFilename;
49 int Len = IFN.length();
50 if (IFN[Len-2] == '.' && IFN[Len-1] == 's') { // Source ends in .s?
51 OutputFilename = std::string(IFN.begin(), IFN.end()-2);
53 OutputFilename = IFN; // Append a .o to it
55 OutputFilename += ".o";
58 std::ofstream Out(OutputFilename.c_str(), ios::out);
60 cerr << "Error opening " << OutputFilename << "!\n";
64 // Make sure that the Out file gets unlink'd from the disk if we get a SIGINT
65 RemoveFileOnSignal(OutputFilename);
67 // In addition to just parsing the input from GCC, we also want to spiff it up
68 // a little bit. Do this now.
71 Passes.add(createFunctionResolvingPass()); // Resolve (...) functions
72 Passes.add(createConstantMergePass()); // Merge dup global constants
73 Passes.add(createDeadInstEliminationPass()); // Remove Dead code/vars
74 Passes.add(createRaiseAllocationsPass()); // call %malloc -> malloc inst
75 Passes.add(createCleanupGCCOutputPass()); // Fix gccisms
76 Passes.add(createIndVarSimplifyPass()); // Simplify indvars
77 if (!StopAtLevelRaise) {
78 Passes.add(createRaisePointerReferencesPass()); // Eliminate casts
79 Passes.add(createPromoteMemoryToRegister()); // Promote alloca's to regs
80 Passes.add(createInstructionCombiningPass()); // Combine silly seq's
81 Passes.add(createDeadInstEliminationPass()); // Kill InstCombine remnants
82 Passes.add(createGCSEPass()); // Remove common subexprs
83 Passes.add(createSCCPPass()); // Constant prop with SCCP
84 Passes.add(createDeadCodeEliminationPass()); // Remove Dead code/vars
86 Passes.add(new WriteBytecodePass(&Out)); // Write bytecode to file...
88 // Run our queue of passes all at once now, efficiently.