1 //===-- llc.cpp - Implement the LLVM Native Code Generator ----------------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This is the llc code generator.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/Bytecode/Reader.h"
15 #include "llvm/Target/TargetMachineImpls.h"
16 #include "llvm/Target/TargetMachine.h"
17 #include "llvm/Transforms/Scalar.h"
18 #include "llvm/Module.h"
19 #include "llvm/PassManager.h"
20 #include "llvm/Pass.h"
21 #include "Support/CommandLine.h"
22 #include "Support/Signals.h"
28 // General options for llc. Other pass-specific options are specified
29 // within the corresponding llc passes, and target-specific options
30 // and back-end code generation options are specified with the target machine.
32 static cl::opt<std::string>
33 InputFilename(cl::Positional, cl::desc("<input bytecode>"), cl::init("-"));
35 static cl::opt<std::string>
36 OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"));
38 static cl::opt<bool> Force("f", cl::desc("Overwrite output files"));
40 enum ArchName { noarch, X86, Sparc, PowerPC, CBackend };
42 static cl::opt<ArchName>
43 Arch("march", cl::desc("Architecture to generate assembly for:"), cl::Prefix,
44 cl::values(clEnumValN(X86, "x86", " IA-32 (Pentium and above)"),
45 clEnumValN(Sparc, "sparc", " SPARC V9"),
46 clEnumValN(PowerPC, "powerpc", " PowerPC"),
47 clEnumValN(CBackend, "c", " C backend"),
51 // GetFileNameRoot - Helper function to get the basename of a filename...
52 static inline std::string
53 GetFileNameRoot(const std::string &InputFilename)
55 std::string IFN = InputFilename;
56 std::string outputFilename;
57 int Len = IFN.length();
59 IFN[Len-3] == '.' && IFN[Len-2] == 'b' && IFN[Len-1] == 'c') {
60 outputFilename = std::string(IFN.begin(), IFN.end()-3); // s/.bc/.s/
64 return outputFilename;
68 // main - Entry point for the llc compiler.
70 int main(int argc, char **argv) {
71 cl::ParseCommandLineOptions(argc, argv, " llvm system compiler\n");
73 // Load the module to be compiled...
74 std::auto_ptr<Module> M(ParseBytecodeFile(InputFilename));
76 std::cerr << argv[0] << ": bytecode didn't read correctly.\n";
79 Module &mod = *M.get();
81 // Allocate target machine. First, check whether the user has
82 // explicitly specified an architecture to compile for.
83 TargetMachine* (*TargetMachineAllocator)(const Module&,
84 IntrinsicLowering *) = 0;
87 TargetMachineAllocator = allocateCTargetMachine;
90 TargetMachineAllocator = allocateX86TargetMachine;
93 TargetMachineAllocator = allocateSparcTargetMachine;
96 TargetMachineAllocator = allocatePowerPCTargetMachine;
99 // Decide what the default target machine should be, by looking at
100 // the module. This heuristic (ILP32, LE -> IA32; LP64, BE ->
101 // SPARCV9) is kind of gross, but it will work until we have more
102 // sophisticated target information to work from.
103 if (mod.getEndianness() == Module::LittleEndian &&
104 mod.getPointerSize() == Module::Pointer32) {
105 TargetMachineAllocator = allocateX86TargetMachine;
106 } else if (mod.getEndianness() == Module::BigEndian &&
107 mod.getPointerSize() == Module::Pointer32) {
108 TargetMachineAllocator = allocatePowerPCTargetMachine;
109 } else if (mod.getEndianness() == Module::BigEndian &&
110 mod.getPointerSize() == Module::Pointer64) {
111 TargetMachineAllocator = allocateSparcTargetMachine;
113 // If the module is target independent, favor a target which matches the
114 // current build system.
115 #if defined(i386) || defined(__i386__) || defined(__x86__)
116 TargetMachineAllocator = allocateX86TargetMachine;
117 #elif defined(sparc) || defined(__sparc__) || defined(__sparcv9)
118 TargetMachineAllocator = allocateSparcTargetMachine;
119 #elif defined(__POWERPC__) || defined(__ppc__) || defined(__APPLE__)
120 TargetMachineAllocator = allocatePowerPCTargetMachine;
122 std::cerr << argv[0] << ": module does not specify a target to use. "
123 << "You must use the -march option. If no native target is "
124 << "available, use -march=c to emit C code.\n";
130 std::auto_ptr<TargetMachine> target(TargetMachineAllocator(mod, 0));
131 assert(target.get() && "Could not allocate target machine!");
132 TargetMachine &Target = *target.get();
133 const TargetData &TD = Target.getTargetData();
135 // Build up all of the passes that we want to do to the module...
138 Passes.add(new TargetData("llc", TD.isLittleEndian(), TD.getPointerSize(),
139 TD.getPointerAlignment(), TD.getDoubleAlignment()));
141 // Figure out where we are going to send the output...
142 std::ostream *Out = 0;
143 if (OutputFilename != "") {
144 if (OutputFilename != "-") {
145 // Specified an output filename?
146 if (!Force && std::ifstream(OutputFilename.c_str())) {
147 // If force is not specified, make sure not to overwrite a file!
148 std::cerr << argv[0] << ": error opening '" << OutputFilename
149 << "': file exists!\n"
150 << "Use -f command line argument to force output\n";
153 Out = new std::ofstream(OutputFilename.c_str());
155 // Make sure that the Out file gets unlinked from the disk if we get a
157 RemoveFileOnSignal(OutputFilename);
162 if (InputFilename == "-") {
163 OutputFilename = "-";
166 OutputFilename = GetFileNameRoot(InputFilename);
168 if (Arch != CBackend)
169 OutputFilename += ".s";
171 OutputFilename += ".cbe.c";
173 if (!Force && std::ifstream(OutputFilename.c_str())) {
174 // If force is not specified, make sure not to overwrite a file!
175 std::cerr << argv[0] << ": error opening '" << OutputFilename
176 << "': file exists!\n"
177 << "Use -f command line argument to force output\n";
181 Out = new std::ofstream(OutputFilename.c_str());
183 std::cerr << argv[0] << ": error opening " << OutputFilename << "!\n";
188 // Make sure that the Out file gets unlinked from the disk if we get a
190 RemoveFileOnSignal(OutputFilename);
194 // Ask the target to add backend passes as necessary
195 if (Target.addPassesToEmitAssembly(Passes, *Out)) {
196 std::cerr << argv[0] << ": target '" << Target.getName()
197 << "' does not support static compilation!\n";
198 if (Out != &std::cout) delete Out;
199 // And the Out file is empty and useless, so remove it now.
200 std::remove(OutputFilename.c_str());
203 // Run our queue of passes all at once now, efficiently.
204 Passes.run(*M.get());
207 // Delete the ostream if it's not a stdout stream
208 if (Out != &std::cout) delete Out;