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/ADT/StringExtras.h"
  20 #include "llvm/IR/Instructions.h"
  21 #include "llvm/IR/Intrinsics.h"
  22 #include "llvm/IR/Module.h"
  23 #include "llvm/MC/MCTargetOptionsCommandFlags.h"
  24 #include "llvm/MC/SubtargetFeature.h"
  25 #include "llvm/Support/CodeGen.h"
  26 #include "llvm/Support/CommandLine.h"
  27 #include "llvm/Support/Host.h"
  28 #include "llvm/Target/TargetMachine.h"
  29 #include "llvm/Target/TargetOptions.h"
  30 #include "llvm/Target/TargetRecip.h"
  31 #include <string>
  32 using namespace llvm;
  33
  34 cl::opt<std::string>
  35 MArch("march", cl::desc("Architecture to generate code for (see --version)"));
  36
  37 cl::opt<std::string>
  38 MCPU("mcpu",
  39      cl::desc("Target a specific cpu type (-mcpu=help for details)"),
  40      cl::value_desc("cpu-name"),
  41      cl::init(""));
  42
  43 cl::list<std::string>
  44 MAttrs("mattr",
  45        cl::CommaSeparated,
  46        cl::desc("Target specific attributes (-mattr=help for details)"),
  47        cl::value_desc("a1,+a2,-a3,..."));
  48
  49 cl::opt<Reloc::Model>
  50 RelocModel("relocation-model",
  51            cl::desc("Choose relocation model"),
  52            cl::init(Reloc::Default),
  53            cl::values(
  54               clEnumValN(Reloc::Default, "default",
  55                       "Target default relocation model"),
  56               clEnumValN(Reloc::Static, "static",
  57                       "Non-relocatable code"),
  58               clEnumValN(Reloc::PIC_, "pic",
  59                       "Fully relocatable, position independent code"),
  60               clEnumValN(Reloc::DynamicNoPIC, "dynamic-no-pic",
  61                       "Relocatable external references, non-relocatable code"),
  62               clEnumValEnd));
  63
  64 cl::opt<ThreadModel::Model>
  65 TMModel("thread-model",
  66         cl::desc("Choose threading model"),
  67         cl::init(ThreadModel::POSIX),
  68         cl::values(clEnumValN(ThreadModel::POSIX, "posix",
  69                               "POSIX thread model"),
  70                    clEnumValN(ThreadModel::Single, "single",
  71                               "Single thread model"),
  72                    clEnumValEnd));
  73
  74 cl::opt<llvm::CodeModel::Model>
  75 CMModel("code-model",
  76         cl::desc("Choose code model"),
  77         cl::init(CodeModel::Default),
  78         cl::values(clEnumValN(CodeModel::Default, "default",
  79                               "Target default code model"),
  80                    clEnumValN(CodeModel::Small, "small",
  81                               "Small code model"),
  82                    clEnumValN(CodeModel::Kernel, "kernel",
  83                               "Kernel code model"),
  84                    clEnumValN(CodeModel::Medium, "medium",
  85                               "Medium code model"),
  86                    clEnumValN(CodeModel::Large, "large",
  87                               "Large code model"),
  88                    clEnumValEnd));
  89
  90 cl::opt<TargetMachine::CodeGenFileType>
  91 FileType("filetype", cl::init(TargetMachine::CGFT_AssemblyFile),
  92   cl::desc("Choose a file type (not all types are supported by all targets):"),
  93   cl::values(
  94              clEnumValN(TargetMachine::CGFT_AssemblyFile, "asm",
  95                         "Emit an assembly ('.s') file"),
  96              clEnumValN(TargetMachine::CGFT_ObjectFile, "obj",
  97                         "Emit a native object ('.o') file"),
  98              clEnumValN(TargetMachine::CGFT_Null, "null",
  99                         "Emit nothing, for performance testing"),
 100              clEnumValEnd));
 101
 102 cl::opt<bool>
 103 EnableFPMAD("enable-fp-mad",
 104             cl::desc("Enable less precise MAD instructions to be generated"),
 105             cl::init(false));
 106
 107 cl::opt<bool>
 108 DisableFPElim("disable-fp-elim",
 109               cl::desc("Disable frame pointer elimination optimization"),
 110               cl::init(false));
 111
 112 cl::opt<bool>
 113 EnableUnsafeFPMath("enable-unsafe-fp-math",
 114                 cl::desc("Enable optimizations that may decrease FP precision"),
 115                 cl::init(false));
 116
 117 cl::opt<bool>
 118 EnableNoInfsFPMath("enable-no-infs-fp-math",
 119                 cl::desc("Enable FP math optimizations that assume no +-Infs"),
 120                 cl::init(false));
 121
 122 cl::opt<bool>
 123 EnableNoNaNsFPMath("enable-no-nans-fp-math",
 124                    cl::desc("Enable FP math optimizations that assume no NaNs"),
 125                    cl::init(false));
 126
 127 cl::opt<bool>
 128 EnableHonorSignDependentRoundingFPMath("enable-sign-dependent-rounding-fp-math",
 129       cl::Hidden,
 130       cl::desc("Force codegen to assume rounding mode can change dynamically"),
 131       cl::init(false));
 132
 133 cl::opt<llvm::FloatABI::ABIType>
 134 FloatABIForCalls("float-abi",
 135                  cl::desc("Choose float ABI type"),
 136                  cl::init(FloatABI::Default),
 137                  cl::values(
 138                      clEnumValN(FloatABI::Default, "default",
 139                                 "Target default float ABI type"),
 140                      clEnumValN(FloatABI::Soft, "soft",
 141                                 "Soft float ABI (implied by -soft-float)"),
 142                      clEnumValN(FloatABI::Hard, "hard",
 143                                 "Hard float ABI (uses FP registers)"),
 144                      clEnumValEnd));
 145
 146 cl::opt<llvm::FPOpFusion::FPOpFusionMode>
 147 FuseFPOps("fp-contract",
 148           cl::desc("Enable aggressive formation of fused FP ops"),
 149           cl::init(FPOpFusion::Standard),
 150           cl::values(
 151               clEnumValN(FPOpFusion::Fast, "fast",
 152                          "Fuse FP ops whenever profitable"),
 153               clEnumValN(FPOpFusion::Standard, "on",
 154                          "Only fuse 'blessed' FP ops."),
 155               clEnumValN(FPOpFusion::Strict, "off",
 156                          "Only fuse FP ops when the result won't be affected."),
 157               clEnumValEnd));
 158
 159 cl::list<std::string>
 160 ReciprocalOps("recip",
 161   cl::CommaSeparated,
 162   cl::desc("Choose reciprocal operation types and parameters."),
 163   cl::value_desc("all,none,default,divf,!vec-sqrtd,vec-divd:0,sqrt:9..."));
 164
 165 cl::opt<bool>
 166 DontPlaceZerosInBSS("nozero-initialized-in-bss",
 167               cl::desc("Don't place zero-initialized symbols into bss section"),
 168               cl::init(false));
 169
 170 cl::opt<bool>
 171 EnableGuaranteedTailCallOpt("tailcallopt",
 172   cl::desc("Turn fastcc calls into tail calls by (potentially) changing ABI."),
 173   cl::init(false));
 174
 175 cl::opt<bool>
 176 DisableTailCalls("disable-tail-calls",
 177                  cl::desc("Never emit tail calls"),
 178                  cl::init(false));
 179
 180 cl::opt<unsigned>
 181 OverrideStackAlignment("stack-alignment",
 182                        cl::desc("Override default stack alignment"),
 183                        cl::init(0));
 184
 185 cl::opt<bool>
 186 StackRealign("stackrealign",
 187              cl::desc("Force align the stack to the minimum alignment"),
 188              cl::init(false));
 189
 190 cl::opt<std::string>
 191 TrapFuncName("trap-func", cl::Hidden,
 192         cl::desc("Emit a call to trap function rather than a trap instruction"),
 193         cl::init(""));
 194
 195 cl::opt<bool>
 196 EnablePIE("enable-pie",
 197           cl::desc("Assume the creation of a position independent executable."),
 198           cl::init(false));
 199
 200 cl::opt<bool>
 201 UseCtors("use-ctors",
 202              cl::desc("Use .ctors instead of .init_array."),
 203              cl::init(false));
 204
 205 cl::opt<std::string> StopAfter("stop-after",
 206                             cl::desc("Stop compilation after a specific pass"),
 207                             cl::value_desc("pass-name"),
 208                                       cl::init(""));
 209 cl::opt<std::string> StartAfter("start-after",
 210                           cl::desc("Resume compilation after a specific pass"),
 211                           cl::value_desc("pass-name"),
 212                           cl::init(""));
 213
 214 cl::opt<std::string>
 215     RunPass("run-pass", cl::desc("Run compiler only for one specific pass"),
 216             cl::value_desc("pass-name"), cl::init(""));
 217
 218 cl::opt<bool> DataSections("data-sections",
 219                            cl::desc("Emit data into separate sections"),
 220                            cl::init(false));
 221
 222 cl::opt<bool>
 223 FunctionSections("function-sections",
 224                  cl::desc("Emit functions into separate sections"),
 225                  cl::init(false));
 226
 227 cl::opt<bool> EmulatedTLS("emulated-tls",
 228                           cl::desc("Use emulated TLS model"),
 229                           cl::init(false));
 230
 231 cl::opt<bool> UniqueSectionNames("unique-section-names",
 232                                  cl::desc("Give unique names to every section"),
 233                                  cl::init(true));
 234
 235 cl::opt<llvm::JumpTable::JumpTableType>
 236 JTableType("jump-table-type",
 237           cl::desc("Choose the type of Jump-Instruction Table for jumptable."),
 238           cl::init(JumpTable::Single),
 239           cl::values(
 240               clEnumValN(JumpTable::Single, "single",
 241                          "Create a single table for all jumptable functions"),
 242               clEnumValN(JumpTable::Arity, "arity",
 243                          "Create one table per number of parameters."),
 244               clEnumValN(JumpTable::Simplified, "simplified",
 245                          "Create one table per simplified function type."),
 246               clEnumValN(JumpTable::Full, "full",
 247                          "Create one table per unique function type."),
 248               clEnumValEnd));
 249
 250 // Common utility function tightly tied to the options listed here. Initializes
 251 // a TargetOptions object with CodeGen flags and returns it.
 252 static inline TargetOptions InitTargetOptionsFromCodeGenFlags() {
 253   TargetOptions Options;
 254   Options.LessPreciseFPMADOption = EnableFPMAD;
 255   Options.AllowFPOpFusion = FuseFPOps;
 256   Options.Reciprocals = TargetRecip(ReciprocalOps);
 257   Options.UnsafeFPMath = EnableUnsafeFPMath;
 258   Options.NoInfsFPMath = EnableNoInfsFPMath;
 259   Options.NoNaNsFPMath = EnableNoNaNsFPMath;
 260   Options.HonorSignDependentRoundingFPMathOption =
 261       EnableHonorSignDependentRoundingFPMath;
 262   if (FloatABIForCalls != FloatABI::Default)
 263     Options.FloatABIType = FloatABIForCalls;
 264   Options.NoZerosInBSS = DontPlaceZerosInBSS;
 265   Options.GuaranteedTailCallOpt = EnableGuaranteedTailCallOpt;
 266   Options.StackAlignmentOverride = OverrideStackAlignment;
 267   Options.PositionIndependentExecutable = EnablePIE;
 268   Options.UseInitArray = !UseCtors;
 269   Options.DataSections = DataSections;
 270   Options.FunctionSections = FunctionSections;
 271   Options.UniqueSectionNames = UniqueSectionNames;
 272   Options.EmulatedTLS = EmulatedTLS;
 273
 274   Options.MCOptions = InitMCTargetOptionsFromFlags();
 275   Options.JTType = JTableType;
 276
 277   Options.ThreadModel = TMModel;
 278
 279   return Options;
 280 }
 281
 282 static inline std::string getCPUStr() {
 283   // If user asked for the 'native' CPU, autodetect here. If autodection fails,
 284   // this will set the CPU to an empty string which tells the target to
 285   // pick a basic default.
 286   if (MCPU == "native")
 287     return sys::getHostCPUName();
 288
 289   return MCPU;
 290 }
 291
 292 static inline std::string getFeaturesStr() {
 293   SubtargetFeatures Features;
 294
 295   // If user asked for the 'native' CPU, we need to autodetect features.
 296   // This is necessary for x86 where the CPU might not support all the
 297   // features the autodetected CPU name lists in the target. For example,
 298   // not all Sandybridge processors support AVX.
 299   if (MCPU == "native") {
 300     StringMap<bool> HostFeatures;
 301     if (sys::getHostCPUFeatures(HostFeatures))
 302       for (auto &F : HostFeatures)
 303         Features.AddFeature(F.first(), F.second);
 304   }
 305
 306   for (unsigned i = 0; i != MAttrs.size(); ++i)
 307     Features.AddFeature(MAttrs[i]);
 308
 309   return Features.getString();
 310 }
 311
 312 /// \brief Set function attributes of functions in Module M based on CPU,
 313 /// Features, and command line flags.
 314 static inline void setFunctionAttributes(StringRef CPU, StringRef Features,
 315                                          Module &M) {
 316   for (auto &F : M) {
 317     auto &Ctx = F.getContext();
 318     AttributeSet Attrs = F.getAttributes(), NewAttrs;
 319
 320     if (!CPU.empty())
 321       NewAttrs = NewAttrs.addAttribute(Ctx, AttributeSet::FunctionIndex,
 322                                        "target-cpu", CPU);
 323
 324     if (!Features.empty())
 325       NewAttrs = NewAttrs.addAttribute(Ctx, AttributeSet::FunctionIndex,
 326                                        "target-features", Features);
 327
 328     if (DisableFPElim.getNumOccurrences() > 0)
 329       NewAttrs = NewAttrs.addAttribute(Ctx, AttributeSet::FunctionIndex,
 330                                        "no-frame-pointer-elim",
 331                                        DisableFPElim ? "true" : "false");
 332
 333     if (DisableTailCalls.getNumOccurrences() > 0)
 334       NewAttrs = NewAttrs.addAttribute(Ctx, AttributeSet::FunctionIndex,
 335                                        "disable-tail-calls",
 336                                        toStringRef(DisableTailCalls));
 337
 338     if (StackRealign)
 339       NewAttrs = NewAttrs.addAttribute(Ctx, AttributeSet::FunctionIndex,
 340                                        "stackrealign");
 341
 342     if (TrapFuncName.getNumOccurrences() > 0)
 343       for (auto &B : F)
 344         for (auto &I : B)
 345           if (auto *Call = dyn_cast<CallInst>(&I))
 346             if (const auto *F = Call->getCalledFunction())
 347               if (F->getIntrinsicID() == Intrinsic::debugtrap ||
 348                   F->getIntrinsicID() == Intrinsic::trap)
 349                 Call->addAttribute(llvm::AttributeSet::FunctionIndex,
 350                                    "trap-func-name", TrapFuncName);
 351
 352     // Let NewAttrs override Attrs.
 353     NewAttrs = Attrs.addAttributes(Ctx, AttributeSet::FunctionIndex, NewAttrs);
 354     F.setAttributes(NewAttrs);
 355   }
 356 }
 357
 358 #endif