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/Transforms/Scalar.h"
15 #include "llvm/PassManager.h"
16 #include "llvm/CodeGen/AsmPrinter.h"
17 #include "llvm/CodeGen/Passes.h"
18 #include "llvm/CodeGen/MachineFunctionAnalysis.h"
19 #include "llvm/CodeGen/MachineModuleInfo.h"
20 #include "llvm/Target/TargetInstrInfo.h"
21 #include "llvm/Target/TargetLowering.h"
22 #include "llvm/Target/TargetLoweringObjectFile.h"
23 #include "llvm/Target/TargetMachine.h"
24 #include "llvm/Target/TargetOptions.h"
25 #include "llvm/Target/TargetSubtargetInfo.h"
26 #include "llvm/Target/TargetRegisterInfo.h"
27 #include "llvm/MC/MCAsmInfo.h"
28 #include "llvm/MC/MCContext.h"
29 #include "llvm/MC/MCInstrInfo.h"
30 #include "llvm/MC/MCStreamer.h"
31 #include "llvm/MC/MCSubtargetInfo.h"
32 #include "llvm/ADT/OwningPtr.h"
33 #include "llvm/Support/CommandLine.h"
34 #include "llvm/Support/FormattedStream.h"
35 #include "llvm/Support/ErrorHandling.h"
36 #include "llvm/Support/TargetRegistry.h"
39 // Enable or disable FastISel. Both options are needed, because
40 // FastISel is enabled by default with -fast, and we wish to be
41 // able to enable or disable fast-isel independently from -O0.
42 static cl::opt<cl::boolOrDefault>
43 EnableFastISelOption("fast-isel", cl::Hidden,
44 cl::desc("Enable the \"fast\" instruction selector"));
46 static cl::opt<bool> ShowMCEncoding("show-mc-encoding", cl::Hidden,
47 cl::desc("Show encoding in .s output"));
48 static cl::opt<bool> ShowMCInst("show-mc-inst", cl::Hidden,
49 cl::desc("Show instruction structure in .s output"));
51 static cl::opt<cl::boolOrDefault>
52 AsmVerbose("asm-verbose", cl::desc("Add comments to directives."),
53 cl::init(cl::BOU_UNSET));
55 static bool getVerboseAsm() {
57 case cl::BOU_UNSET: return TargetMachine::getAsmVerbosityDefault();
58 case cl::BOU_TRUE: return true;
59 case cl::BOU_FALSE: return false;
61 llvm_unreachable("Invalid verbose asm state");
64 LLVMTargetMachine::LLVMTargetMachine(const Target &T, StringRef Triple,
65 StringRef CPU, StringRef FS,
66 TargetOptions Options,
67 Reloc::Model RM, CodeModel::Model CM,
69 : TargetMachine(T, Triple, CPU, FS, Options) {
70 CodeGenInfo = T.createMCCodeGenInfo(Triple, RM, CM, OL);
71 AsmInfo = T.createMCAsmInfo(Triple);
72 // TargetSelect.h moved to a different directory between LLVM 2.9 and 3.0,
73 // and if the old one gets included then MCAsmInfo will be NULL and
75 // Provide the user with a useful error message about what's wrong.
76 assert(AsmInfo && "MCAsmInfo not initialized."
77 "Make sure you include the correct TargetSelect.h"
78 "and that InitializeAllTargetMCs() is being invoked!");
81 /// Turn exception handling constructs into something the code generators can
83 static void addPassesToHandleExceptions(TargetMachine *TM,
84 PassManagerBase &PM) {
85 switch (TM->getMCAsmInfo()->getExceptionHandlingType()) {
86 case ExceptionHandling::SjLj:
87 // SjLj piggy-backs on dwarf for this bit. The cleanups done apply to both
88 // Dwarf EH prepare needs to be run after SjLj prepare. Otherwise,
89 // catch info can get misplaced when a selector ends up more than one block
90 // removed from the parent invoke(s). This could happen when a landing
91 // pad is shared by multiple invokes and is also a target of a normal
92 // edge from elsewhere.
93 PM.add(createSjLjEHPass(TM->getTargetLowering()));
95 case ExceptionHandling::DwarfCFI:
96 case ExceptionHandling::ARM:
97 case ExceptionHandling::Win64:
98 PM.add(createDwarfEHPass(TM));
100 case ExceptionHandling::None:
101 PM.add(createLowerInvokePass(TM->getTargetLowering()));
103 // The lower invoke pass may create unreachable code. Remove it.
104 PM.add(createUnreachableBlockEliminationPass());
109 /// addPassesToX helper drives creation and initialization of TargetPassConfig.
110 static MCContext *addPassesToGenerateCode(LLVMTargetMachine *TM,
112 bool DisableVerify) {
113 // Targets may override createPassConfig to provide a target-specific sublass.
114 TargetPassConfig *PassConfig = TM->createPassConfig(PM);
116 // Set PassConfig options provided by TargetMachine.
117 PassConfig->setDisableVerify(DisableVerify);
119 PassConfig->addIRPasses();
121 addPassesToHandleExceptions(TM, PM);
123 PassConfig->addISelPrepare();
125 // Install a MachineModuleInfo class, which is an immutable pass that holds
126 // all the per-module stuff we're generating, including MCContext.
127 MachineModuleInfo *MMI =
128 new MachineModuleInfo(*TM->getMCAsmInfo(), *TM->getRegisterInfo(),
129 &TM->getTargetLowering()->getObjFileLowering());
131 MCContext *Context = &MMI->getContext(); // Return the MCContext specifically by-ref.
133 // Set up a MachineFunction for the rest of CodeGen to work on.
134 PM.add(new MachineFunctionAnalysis(*TM));
136 // Enable FastISel with -fast, but allow that to be overridden.
137 if (EnableFastISelOption == cl::BOU_TRUE ||
138 (TM->getOptLevel() == CodeGenOpt::None &&
139 EnableFastISelOption != cl::BOU_FALSE))
140 TM->setFastISel(true);
142 // Ask the target for an isel.
143 if (PassConfig->addInstSelector())
146 PassConfig->addMachinePasses();
151 bool LLVMTargetMachine::addPassesToEmitFile(PassManagerBase &PM,
152 formatted_raw_ostream &Out,
153 CodeGenFileType FileType,
154 bool DisableVerify) {
155 // Add common CodeGen passes.
156 MCContext *Context = addPassesToGenerateCode(this, PM, DisableVerify);
160 if (hasMCSaveTempLabels())
161 Context->setAllowTemporaryLabels(false);
163 const MCAsmInfo &MAI = *getMCAsmInfo();
164 const MCSubtargetInfo &STI = getSubtarget<MCSubtargetInfo>();
165 OwningPtr<MCStreamer> AsmStreamer;
168 case CGFT_AssemblyFile: {
169 MCInstPrinter *InstPrinter =
170 getTarget().createMCInstPrinter(MAI.getAssemblerDialect(), MAI, STI);
172 // Create a code emitter if asked to show the encoding.
173 MCCodeEmitter *MCE = 0;
174 MCAsmBackend *MAB = 0;
175 if (ShowMCEncoding) {
176 const MCSubtargetInfo &STI = getSubtarget<MCSubtargetInfo>();
177 MCE = getTarget().createMCCodeEmitter(*getInstrInfo(), STI, *Context);
178 MAB = getTarget().createMCAsmBackend(getTargetTriple());
181 MCStreamer *S = getTarget().createAsmStreamer(*Context, Out,
185 hasMCUseDwarfDirectory(),
189 AsmStreamer.reset(S);
192 case CGFT_ObjectFile: {
193 // Create the code emitter for the target if it exists. If not, .o file
195 MCCodeEmitter *MCE = getTarget().createMCCodeEmitter(*getInstrInfo(), STI,
197 MCAsmBackend *MAB = getTarget().createMCAsmBackend(getTargetTriple());
198 if (MCE == 0 || MAB == 0)
201 AsmStreamer.reset(getTarget().createMCObjectStreamer(getTargetTriple(),
203 MCE, hasMCRelaxAll(),
204 hasMCNoExecStack()));
205 AsmStreamer.get()->InitSections();
209 // The Null output is intended for use for performance analysis and testing,
211 AsmStreamer.reset(createNullStreamer(*Context));
215 // Create the AsmPrinter, which takes ownership of AsmStreamer if successful.
216 FunctionPass *Printer = getTarget().createAsmPrinter(*this, *AsmStreamer);
220 // If successful, createAsmPrinter took ownership of AsmStreamer.
225 PM.add(createGCInfoDeleter());
229 /// addPassesToEmitMachineCode - Add passes to the specified pass manager to
230 /// get machine code emitted. This uses a JITCodeEmitter object to handle
231 /// actually outputting the machine code and resolving things like the address
232 /// of functions. This method should returns true if machine code emission is
235 bool LLVMTargetMachine::addPassesToEmitMachineCode(PassManagerBase &PM,
237 bool DisableVerify) {
238 // Add common CodeGen passes.
239 MCContext *Context = addPassesToGenerateCode(this, PM, DisableVerify);
243 addCodeEmitter(PM, JCE);
244 PM.add(createGCInfoDeleter());
246 return false; // success!
249 /// addPassesToEmitMC - Add passes to the specified pass manager to get
250 /// machine code emitted with the MCJIT. This method returns true if machine
251 /// code is not supported. It fills the MCContext Ctx pointer which can be
252 /// used to build custom MCStreamer.
254 bool LLVMTargetMachine::addPassesToEmitMC(PassManagerBase &PM,
257 bool DisableVerify) {
258 // Add common CodeGen passes.
259 Ctx = addPassesToGenerateCode(this, PM, DisableVerify);
263 if (hasMCSaveTempLabels())
264 Ctx->setAllowTemporaryLabels(false);
266 // Create the code emitter for the target if it exists. If not, .o file
268 const MCSubtargetInfo &STI = getSubtarget<MCSubtargetInfo>();
269 MCCodeEmitter *MCE = getTarget().createMCCodeEmitter(*getInstrInfo(),STI, *Ctx);
270 MCAsmBackend *MAB = getTarget().createMCAsmBackend(getTargetTriple());
271 if (MCE == 0 || MAB == 0)
274 OwningPtr<MCStreamer> AsmStreamer;
275 AsmStreamer.reset(getTarget().createMCObjectStreamer(getTargetTriple(), *Ctx,
278 hasMCNoExecStack()));
279 AsmStreamer.get()->InitSections();
281 // Create the AsmPrinter, which takes ownership of AsmStreamer if successful.
282 FunctionPass *Printer = getTarget().createAsmPrinter(*this, *AsmStreamer);
286 // If successful, createAsmPrinter took ownership of AsmStreamer.
291 return false; // success!