1 //===-- LLVMTargetMachine.cpp - Implement the LLVMTargetMachine class -----===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the LLVMTargetMachine class.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/Target/TargetMachine.h"
15 #include "llvm/PassManager.h"
16 #include "llvm/Pass.h"
17 #include "llvm/Assembly/PrintModulePass.h"
18 #include "llvm/CodeGen/AsmPrinter.h"
19 #include "llvm/CodeGen/Passes.h"
20 #include "llvm/CodeGen/GCStrategy.h"
21 #include "llvm/CodeGen/MachineFunctionAnalysis.h"
22 #include "llvm/Target/TargetOptions.h"
23 #include "llvm/MC/MCAsmInfo.h"
24 #include "llvm/Target/TargetRegistry.h"
25 #include "llvm/Transforms/Scalar.h"
26 #include "llvm/Support/CommandLine.h"
27 #include "llvm/Support/FormattedStream.h"
34 static cl::opt<bool> PrintLSR("print-lsr-output", cl::Hidden,
35 cl::desc("Print LLVM IR produced by the loop-reduce pass"));
36 static cl::opt<bool> PrintISelInput("print-isel-input", cl::Hidden,
37 cl::desc("Print LLVM IR input to isel pass"));
38 static cl::opt<bool> PrintEmittedAsm("print-emitted-asm", cl::Hidden,
39 cl::desc("Dump emitter generated instructions as assembly"));
40 static cl::opt<bool> PrintGCInfo("print-gc", cl::Hidden,
41 cl::desc("Dump garbage collector data"));
42 static cl::opt<bool> VerifyMachineCode("verify-machineinstrs", cl::Hidden,
43 cl::desc("Verify generated machine code"),
44 cl::init(getenv("LLVM_VERIFY_MACHINEINSTRS")!=NULL));
46 // When this works it will be on by default.
48 DisablePostRAScheduler("disable-post-RA-scheduler",
49 cl::desc("Disable scheduling after register allocation"),
52 // Enable or disable FastISel. Both options are needed, because
53 // FastISel is enabled by default with -fast, and we wish to be
54 // able to enable or disable fast-isel independently from -O0.
55 static cl::opt<cl::boolOrDefault>
56 EnableFastISelOption("fast-isel", cl::Hidden,
57 cl::desc("Enable the \"fast\" instruction selector"));
60 LLVMTargetMachine::LLVMTargetMachine(const Target &T,
61 const std::string &TargetTriple)
63 AsmInfo = T.createAsmInfo(TargetTriple);
69 LLVMTargetMachine::addPassesToEmitFile(PassManagerBase &PM,
70 formatted_raw_ostream &Out,
71 CodeGenFileType FileType,
72 CodeGenOpt::Level OptLevel) {
73 // Add common CodeGen passes.
74 if (addCommonCodeGenPasses(PM, OptLevel))
75 return FileModel::Error;
77 // Fold redundant debug labels.
78 PM.add(createDebugLabelFoldingPass());
81 PM.add(createMachineFunctionPrinterPass(errs()));
83 if (addPreEmitPass(PM, OptLevel) && PrintMachineCode)
84 PM.add(createMachineFunctionPrinterPass(errs()));
86 if (OptLevel != CodeGenOpt::None)
87 PM.add(createCodePlacementOptPass());
92 case TargetMachine::AssemblyFile:
93 if (addAssemblyEmitter(PM, OptLevel, getAsmVerbosityDefault(), Out))
94 return FileModel::Error;
95 return FileModel::AsmFile;
96 case TargetMachine::ObjectFile:
97 if (getMachOWriterInfo())
98 return FileModel::MachOFile;
99 else if (getELFWriterInfo())
100 return FileModel::ElfFile;
103 return FileModel::Error;
106 bool LLVMTargetMachine::addAssemblyEmitter(PassManagerBase &PM,
107 CodeGenOpt::Level OptLevel,
109 formatted_raw_ostream &Out) {
110 FunctionPass *Printer =
111 getTarget().createAsmPrinter(Out, *this, getMCAsmInfo(), Verbose);
119 /// addPassesToEmitFileFinish - If the passes to emit the specified file had to
120 /// be split up (e.g., to add an object writer pass), this method can be used to
121 /// finish up adding passes to emit the file, if necessary.
122 bool LLVMTargetMachine::addPassesToEmitFileFinish(PassManagerBase &PM,
123 MachineCodeEmitter *MCE,
124 CodeGenOpt::Level OptLevel) {
126 addSimpleCodeEmitter(PM, OptLevel, *MCE);
128 addAssemblyEmitter(PM, OptLevel, true, ferrs());
130 PM.add(createGCInfoDeleter());
132 return false; // success!
135 /// addPassesToEmitFileFinish - If the passes to emit the specified file had to
136 /// be split up (e.g., to add an object writer pass), this method can be used to
137 /// finish up adding passes to emit the file, if necessary.
138 bool LLVMTargetMachine::addPassesToEmitFileFinish(PassManagerBase &PM,
140 CodeGenOpt::Level OptLevel) {
142 addSimpleCodeEmitter(PM, OptLevel, *JCE);
144 addAssemblyEmitter(PM, OptLevel, true, ferrs());
146 PM.add(createGCInfoDeleter());
148 return false; // success!
151 /// addPassesToEmitFileFinish - If the passes to emit the specified file had to
152 /// be split up (e.g., to add an object writer pass), this method can be used to
153 /// finish up adding passes to emit the file, if necessary.
154 bool LLVMTargetMachine::addPassesToEmitFileFinish(PassManagerBase &PM,
155 ObjectCodeEmitter *OCE,
156 CodeGenOpt::Level OptLevel) {
158 addSimpleCodeEmitter(PM, OptLevel, *OCE);
160 addAssemblyEmitter(PM, OptLevel, true, ferrs());
162 PM.add(createGCInfoDeleter());
164 return false; // success!
167 /// addPassesToEmitMachineCode - Add passes to the specified pass manager to
168 /// get machine code emitted. This uses a MachineCodeEmitter object to handle
169 /// actually outputting the machine code and resolving things like the address
170 /// of functions. This method should returns true if machine code emission is
173 bool LLVMTargetMachine::addPassesToEmitMachineCode(PassManagerBase &PM,
174 MachineCodeEmitter &MCE,
175 CodeGenOpt::Level OptLevel) {
176 // Add common CodeGen passes.
177 if (addCommonCodeGenPasses(PM, OptLevel))
180 if (addPreEmitPass(PM, OptLevel) && PrintMachineCode)
181 PM.add(createMachineFunctionPrinterPass(errs()));
183 addCodeEmitter(PM, OptLevel, MCE);
185 addAssemblyEmitter(PM, OptLevel, true, ferrs());
187 PM.add(createGCInfoDeleter());
189 return false; // success!
192 /// addPassesToEmitMachineCode - Add passes to the specified pass manager to
193 /// get machine code emitted. This uses a MachineCodeEmitter object to handle
194 /// actually outputting the machine code and resolving things like the address
195 /// of functions. This method should returns true if machine code emission is
198 bool LLVMTargetMachine::addPassesToEmitMachineCode(PassManagerBase &PM,
200 CodeGenOpt::Level OptLevel) {
201 // Add common CodeGen passes.
202 if (addCommonCodeGenPasses(PM, OptLevel))
205 if (addPreEmitPass(PM, OptLevel) && PrintMachineCode)
206 PM.add(createMachineFunctionPrinterPass(errs()));
208 addCodeEmitter(PM, OptLevel, JCE);
210 addAssemblyEmitter(PM, OptLevel, true, ferrs());
212 PM.add(createGCInfoDeleter());
214 return false; // success!
217 static void printAndVerify(PassManagerBase &PM,
218 bool allowDoubleDefs = false) {
219 if (PrintMachineCode)
220 PM.add(createMachineFunctionPrinterPass(errs()));
222 if (VerifyMachineCode)
223 PM.add(createMachineVerifierPass(allowDoubleDefs));
226 /// addCommonCodeGenPasses - Add standard LLVM codegen passes used for both
227 /// emitting to assembly files or machine code output.
229 bool LLVMTargetMachine::addCommonCodeGenPasses(PassManagerBase &PM,
230 CodeGenOpt::Level OptLevel) {
231 // Standard LLVM-Level Passes.
233 // Run loop strength reduction before anything else.
234 if (OptLevel != CodeGenOpt::None) {
235 PM.add(createLoopStrengthReducePass(getTargetLowering()));
237 PM.add(createPrintFunctionPass("\n\n*** Code after LSR ***\n", &errs()));
240 // Turn exception handling constructs into something the code generators can
242 switch (getMCAsmInfo()->getExceptionHandlingType())
244 case ExceptionHandling::SjLj:
245 // SjLj piggy-backs on dwarf for this bit. The cleanups done apply to both
246 PM.add(createDwarfEHPass(getTargetLowering(), OptLevel==CodeGenOpt::None));
247 PM.add(createSjLjEHPass(getTargetLowering()));
249 case ExceptionHandling::Dwarf:
250 PM.add(createDwarfEHPass(getTargetLowering(), OptLevel==CodeGenOpt::None));
252 case ExceptionHandling::None:
253 PM.add(createLowerInvokePass(getTargetLowering()));
257 PM.add(createGCLoweringPass());
259 // Make sure that no unreachable blocks are instruction selected.
260 PM.add(createUnreachableBlockEliminationPass());
262 if (OptLevel != CodeGenOpt::None)
263 PM.add(createCodeGenPreparePass(getTargetLowering()));
265 PM.add(createStackProtectorPass(getTargetLowering()));
268 PM.add(createPrintFunctionPass("\n\n"
269 "*** Final LLVM Code input to ISel ***\n",
272 // Standard Lower-Level Passes.
274 // Set up a MachineFunction for the rest of CodeGen to work on.
275 PM.add(new MachineFunctionAnalysis(*this, OptLevel));
277 // Enable FastISel with -fast, but allow that to be overridden.
278 if (EnableFastISelOption == cl::BOU_TRUE ||
279 (OptLevel == CodeGenOpt::None && EnableFastISelOption != cl::BOU_FALSE))
280 EnableFastISel = true;
282 // Ask the target for an isel.
283 if (addInstSelector(PM, OptLevel))
286 // Print the instruction selected machine code...
287 printAndVerify(PM, /* allowDoubleDefs= */ true);
289 if (OptLevel != CodeGenOpt::None) {
290 PM.add(createMachineLICMPass());
291 PM.add(createMachineSinkingPass());
292 printAndVerify(PM, /* allowDoubleDefs= */ true);
295 // Run pre-ra passes.
296 if (addPreRegAlloc(PM, OptLevel))
297 printAndVerify(PM, /* allowDoubleDefs= */ true);
299 // Perform register allocation.
300 PM.add(createRegisterAllocator());
302 // Perform stack slot coloring.
303 if (OptLevel != CodeGenOpt::None)
304 // FIXME: Re-enable coloring with register when it's capable of adding
306 PM.add(createStackSlotColoringPass(false));
308 printAndVerify(PM); // Print the register-allocated code
310 // Run post-ra passes.
311 if (addPostRegAlloc(PM, OptLevel))
314 PM.add(createLowerSubregsPass());
317 // Insert prolog/epilog code. Eliminate abstract frame index references...
318 PM.add(createPrologEpilogCodeInserter());
321 // Second pass scheduler.
322 if (OptLevel != CodeGenOpt::None && !DisablePostRAScheduler) {
323 PM.add(createPostRAScheduler());
327 // Branch folding must be run after regalloc and prolog/epilog insertion.
328 if (OptLevel != CodeGenOpt::None) {
329 PM.add(createBranchFoldingPass(getEnableTailMergeDefault()));
333 PM.add(createGCMachineCodeAnalysisPass());
337 PM.add(createGCInfoPrinter(errs()));