include/llvm/CodeGen/CommandFlags.h

   1 //===-- CommandFlags.h - Command Line Flags Interface -----------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file contains codegen-specific flags that are shared between different
  11 // command line tools. The tools "llc" and "opt" both use this file to prevent
  12 // flag duplication.
  13 //
  14 //===----------------------------------------------------------------------===//
  15
  16 #ifndef LLVM_CODEGEN_COMMANDFLAGS_H
  17 #define LLVM_CODEGEN_COMMANDFLAGS_H
  18
  19 #include "llvm/IR/Module.h"
  20 #include "llvm/MC/MCTargetOptionsCommandFlags.h"
  21 #include "llvm//MC/SubtargetFeature.h"
  22 #include "llvm/Support/CodeGen.h"
  23 #include "llvm/Support/CommandLine.h"
  24 #include "llvm/Support/Host.h"
  25 #include "llvm/Target/TargetMachine.h"
  26 #include "llvm/Target/TargetOptions.h"
  27 #include <string>
  28 using namespace llvm;
  29
  30 cl::opt<std::string>
  31 MArch("march", cl::desc("Architecture to generate code for (see --version)"));
  32
  33 cl::opt<std::string>
  34 MCPU("mcpu",
  35      cl::desc("Target a specific cpu type (-mcpu=help for details)"),
  36      cl::value_desc("cpu-name"),
  37      cl::init(""));
  38
  39 cl::list<std::string>
  40 MAttrs("mattr",
  41        cl::CommaSeparated,
  42        cl::desc("Target specific attributes (-mattr=help for details)"),
  43        cl::value_desc("a1,+a2,-a3,..."));
  44
  45 cl::opt<Reloc::Model>
  46 RelocModel("relocation-model",
  47            cl::desc("Choose relocation model"),
  48            cl::init(Reloc::Default),
  49            cl::values(
  50               clEnumValN(Reloc::Default, "default",
  51                       "Target default relocation model"),
  52               clEnumValN(Reloc::Static, "static",
  53                       "Non-relocatable code"),
  54               clEnumValN(Reloc::PIC_, "pic",
  55                       "Fully relocatable, position independent code"),
  56               clEnumValN(Reloc::DynamicNoPIC, "dynamic-no-pic",
  57                       "Relocatable external references, non-relocatable code"),
  58               clEnumValEnd));
  59
  60 cl::opt<ThreadModel::Model>
  61 TMModel("thread-model",
  62         cl::desc("Choose threading model"),
  63         cl::init(ThreadModel::POSIX),
  64         cl::values(clEnumValN(ThreadModel::POSIX, "posix",
  65                               "POSIX thread model"),
  66                    clEnumValN(ThreadModel::Single, "single",
  67                               "Single thread model"),
  68                    clEnumValEnd));
  69
  70 cl::opt<llvm::CodeModel::Model>
  71 CMModel("code-model",
  72         cl::desc("Choose code model"),
  73         cl::init(CodeModel::Default),
  74         cl::values(clEnumValN(CodeModel::Default, "default",
  75                               "Target default code model"),
  76                    clEnumValN(CodeModel::Small, "small",
  77                               "Small code model"),
  78                    clEnumValN(CodeModel::Kernel, "kernel",
  79                               "Kernel code model"),
  80                    clEnumValN(CodeModel::Medium, "medium",
  81                               "Medium code model"),
  82                    clEnumValN(CodeModel::Large, "large",
  83                               "Large code model"),
  84                    clEnumValEnd));
  85
  86 cl::opt<TargetMachine::CodeGenFileType>
  87 FileType("filetype", cl::init(TargetMachine::CGFT_AssemblyFile),
  88   cl::desc("Choose a file type (not all types are supported by all targets):"),
  89   cl::values(
  90              clEnumValN(TargetMachine::CGFT_AssemblyFile, "asm",
  91                         "Emit an assembly ('.s') file"),
  92              clEnumValN(TargetMachine::CGFT_ObjectFile, "obj",
  93                         "Emit a native object ('.o') file"),
  94              clEnumValN(TargetMachine::CGFT_Null, "null",
  95                         "Emit nothing, for performance testing"),
  96              clEnumValEnd));
  97
  98 cl::opt<bool>
  99 EnableFPMAD("enable-fp-mad",
 100             cl::desc("Enable less precise MAD instructions to be generated"),
 101             cl::init(false));
 102
 103 cl::opt<bool>
 104 DisableFPElim("disable-fp-elim",
 105               cl::desc("Disable frame pointer elimination optimization"),
 106               cl::init(false));
 107
 108 cl::opt<bool>
 109 EnableUnsafeFPMath("enable-unsafe-fp-math",
 110                 cl::desc("Enable optimizations that may decrease FP precision"),
 111                 cl::init(false));
 112
 113 cl::opt<bool>
 114 EnableNoInfsFPMath("enable-no-infs-fp-math",
 115                 cl::desc("Enable FP math optimizations that assume no +-Infs"),
 116                 cl::init(false));
 117
 118 cl::opt<bool>
 119 EnableNoNaNsFPMath("enable-no-nans-fp-math",
 120                    cl::desc("Enable FP math optimizations that assume no NaNs"),
 121                    cl::init(false));
 122
 123 cl::opt<bool>
 124 EnableHonorSignDependentRoundingFPMath("enable-sign-dependent-rounding-fp-math",
 125       cl::Hidden,
 126       cl::desc("Force codegen to assume rounding mode can change dynamically"),
 127       cl::init(false));
 128
 129 cl::opt<llvm::FloatABI::ABIType>
 130 FloatABIForCalls("float-abi",
 131                  cl::desc("Choose float ABI type"),
 132                  cl::init(FloatABI::Default),
 133                  cl::values(
 134                      clEnumValN(FloatABI::Default, "default",
 135                                 "Target default float ABI type"),
 136                      clEnumValN(FloatABI::Soft, "soft",
 137                                 "Soft float ABI (implied by -soft-float)"),
 138                      clEnumValN(FloatABI::Hard, "hard",
 139                                 "Hard float ABI (uses FP registers)"),
 140                      clEnumValEnd));
 141
 142 cl::opt<llvm::FPOpFusion::FPOpFusionMode>
 143 FuseFPOps("fp-contract",
 144           cl::desc("Enable aggressive formation of fused FP ops"),
 145           cl::init(FPOpFusion::Standard),
 146           cl::values(
 147               clEnumValN(FPOpFusion::Fast, "fast",
 148                          "Fuse FP ops whenever profitable"),
 149               clEnumValN(FPOpFusion::Standard, "on",
 150                          "Only fuse 'blessed' FP ops."),
 151               clEnumValN(FPOpFusion::Strict, "off",
 152                          "Only fuse FP ops when the result won't be effected."),
 153               clEnumValEnd));
 154
 155 cl::opt<bool>
 156 DontPlaceZerosInBSS("nozero-initialized-in-bss",
 157               cl::desc("Don't place zero-initialized symbols into bss section"),
 158               cl::init(false));
 159
 160 cl::opt<bool>
 161 EnableGuaranteedTailCallOpt("tailcallopt",
 162   cl::desc("Turn fastcc calls into tail calls by (potentially) changing ABI."),
 163   cl::init(false));
 164
 165 cl::opt<bool>
 166 DisableTailCalls("disable-tail-calls",
 167                  cl::desc("Never emit tail calls"),
 168                  cl::init(false));
 169
 170 cl::opt<unsigned>
 171 OverrideStackAlignment("stack-alignment",
 172                        cl::desc("Override default stack alignment"),
 173                        cl::init(0));
 174
 175 cl::opt<std::string>
 176 TrapFuncName("trap-func", cl::Hidden,
 177         cl::desc("Emit a call to trap function rather than a trap instruction"),
 178         cl::init(""));
 179
 180 cl::opt<bool>
 181 EnablePIE("enable-pie",
 182           cl::desc("Assume the creation of a position independent executable."),
 183           cl::init(false));
 184
 185 cl::opt<bool>
 186 UseCtors("use-ctors",
 187              cl::desc("Use .ctors instead of .init_array."),
 188              cl::init(false));
 189
 190 cl::opt<std::string> StopAfter("stop-after",
 191                             cl::desc("Stop compilation after a specific pass"),
 192                             cl::value_desc("pass-name"),
 193                                       cl::init(""));
 194 cl::opt<std::string> StartAfter("start-after",
 195                           cl::desc("Resume compilation after a specific pass"),
 196                           cl::value_desc("pass-name"),
 197                           cl::init(""));
 198
 199 cl::opt<bool> DataSections("data-sections",
 200                            cl::desc("Emit data into separate sections"),
 201                            cl::init(false));
 202
 203 cl::opt<bool>
 204 FunctionSections("function-sections",
 205                  cl::desc("Emit functions into separate sections"),
 206                  cl::init(false));
 207
 208 cl::opt<bool> UniqueSectionNames("unique-section-names",
 209                                  cl::desc("Give unique names to every section"),
 210                                  cl::init(true));
 211
 212 cl::opt<llvm::JumpTable::JumpTableType>
 213 JTableType("jump-table-type",
 214           cl::desc("Choose the type of Jump-Instruction Table for jumptable."),
 215           cl::init(JumpTable::Single),
 216           cl::values(
 217               clEnumValN(JumpTable::Single, "single",
 218                          "Create a single table for all jumptable functions"),
 219               clEnumValN(JumpTable::Arity, "arity",
 220                          "Create one table per number of parameters."),
 221               clEnumValN(JumpTable::Simplified, "simplified",
 222                          "Create one table per simplified function type."),
 223               clEnumValN(JumpTable::Full, "full",
 224                          "Create one table per unique function type."),
 225               clEnumValEnd));
 226
 227 // Common utility function tightly tied to the options listed here. Initializes
 228 // a TargetOptions object with CodeGen flags and returns it.
 229 static inline TargetOptions InitTargetOptionsFromCodeGenFlags() {
 230   TargetOptions Options;
 231   Options.LessPreciseFPMADOption = EnableFPMAD;
 232   Options.NoFramePointerElim = DisableFPElim;
 233   Options.AllowFPOpFusion = FuseFPOps;
 234   Options.UnsafeFPMath = EnableUnsafeFPMath;
 235   Options.NoInfsFPMath = EnableNoInfsFPMath;
 236   Options.NoNaNsFPMath = EnableNoNaNsFPMath;
 237   Options.HonorSignDependentRoundingFPMathOption =
 238       EnableHonorSignDependentRoundingFPMath;
 239   if (FloatABIForCalls != FloatABI::Default)
 240     Options.FloatABIType = FloatABIForCalls;
 241   Options.NoZerosInBSS = DontPlaceZerosInBSS;
 242   Options.GuaranteedTailCallOpt = EnableGuaranteedTailCallOpt;
 243   Options.DisableTailCalls = DisableTailCalls;
 244   Options.StackAlignmentOverride = OverrideStackAlignment;
 245   Options.TrapFuncName = TrapFuncName;
 246   Options.PositionIndependentExecutable = EnablePIE;
 247   Options.UseInitArray = !UseCtors;
 248   Options.DataSections = DataSections;
 249   Options.FunctionSections = FunctionSections;
 250   Options.UniqueSectionNames = UniqueSectionNames;
 251
 252   Options.MCOptions = InitMCTargetOptionsFromFlags();
 253   Options.JTType = JTableType;
 254
 255   Options.ThreadModel = TMModel;
 256
 257   return Options;
 258 }
 259
 260 static inline std::string getCPUStr() {
 261   // If user asked for the 'native' CPU, autodetect here. If autodection fails,
 262   // this will set the CPU to an empty string which tells the target to
 263   // pick a basic default.
 264   if (MCPU == "native")
 265     return sys::getHostCPUName();
 266
 267   return MCPU;
 268 }
 269
 270 static inline std::string getFeaturesStr() {
 271   SubtargetFeatures Features;
 272
 273   // If user asked for the 'native' CPU, we need to autodetect features.
 274   // This is necessary for x86 where the CPU might not support all the
 275   // features the autodetected CPU name lists in the target. For example,
 276   // not all Sandybridge processors support AVX.
 277   if (MCPU == "native") {
 278     StringMap<bool> HostFeatures;
 279     if (sys::getHostCPUFeatures(HostFeatures))
 280       for (auto &F : HostFeatures)
 281         Features.AddFeature(F.first(), F.second);
 282   }
 283
 284   for (unsigned i = 0; i != MAttrs.size(); ++i)
 285     Features.AddFeature(MAttrs[i]);
 286
 287   return Features.getString();
 288 }
 289
 290 static inline void overrideFunctionAttributes(StringRef CPU, StringRef Features,
 291                                               Module &M) {
 292   for (auto &F : M) {
 293     if (!CPU.empty())
 294       llvm::overrideFunctionAttribute("target-cpu", CPU, F);
 295
 296     if (!Features.empty())
 297       llvm::overrideFunctionAttribute("target-features", Features, F);
 298   }
 299 }
 300
 301 #endif