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