1 //===-- llvm/Target/TargetOptions.h - Target Options ------------*- 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 defines command line option flags that are shared across various 11 // targets. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #ifndef LLVM_TARGET_TARGETOPTIONS_H 16 #define LLVM_TARGET_TARGETOPTIONS_H 17 18 #include "llvm/MC/MCTargetOptions.h" 19 #include <string> 20 21 namespace llvm { 22 class MachineFunction; 23 class StringRef; 24 25 // Possible float ABI settings. Used with FloatABIType in TargetOptions.h. 26 namespace FloatABI { 27 enum ABIType { 28 Default, // Target-specific (either soft or hard depending on triple,etc). 29 Soft, // Soft float. 30 Hard // Hard float. 31 }; 32 } 33 34 namespace FPOpFusion { 35 enum FPOpFusionMode { 36 Fast, // Enable fusion of FP ops wherever it's profitable. 37 Standard, // Only allow fusion of 'blessed' ops (currently just fmuladd). 38 Strict // Never fuse FP-ops. 39 }; 40 } 41 42 namespace JumpTable { 43 enum JumpTableType { 44 Single, // Use a single table for all indirect jumptable calls. 45 Arity, // Use one table per number of function parameters. 46 Simplified, // Use one table per function type, with types projected 47 // into 4 types: pointer to non-function, struct, 48 // primitive, and function pointer. 49 Full // Use one table per unique function type 50 }; 51 } 52 53 class TargetOptions { 54 public: 55 TargetOptions() 56 : PrintMachineCode(false), NoFramePointerElim(false), 57 LessPreciseFPMADOption(false), UnsafeFPMath(false), 58 NoInfsFPMath(false), NoNaNsFPMath(false), 59 HonorSignDependentRoundingFPMathOption(false), UseSoftFloat(false), 60 NoZerosInBSS(false), JITEmitDebugInfo(false), 61 JITEmitDebugInfoToDisk(false), GuaranteedTailCallOpt(false), 62 DisableTailCalls(false), StackAlignmentOverride(0), 63 EnableFastISel(false), PositionIndependentExecutable(false), 64 UseInitArray(false), DisableIntegratedAS(false), 65 CompressDebugSections(false), FunctionSections(false), 66 DataSections(false), TrapUnreachable(false), TrapFuncName(""), 67 FloatABIType(FloatABI::Default), 68 AllowFPOpFusion(FPOpFusion::Standard), JTType(JumpTable::Single) {} 69 70 /// PrintMachineCode - This flag is enabled when the -print-machineinstrs 71 /// option is specified on the command line, and should enable debugging 72 /// output from the code generator. 73 unsigned PrintMachineCode : 1; 74 75 /// NoFramePointerElim - This flag is enabled when the -disable-fp-elim is 76 /// specified on the command line. If the target supports the frame pointer 77 /// elimination optimization, this option should disable it. 78 unsigned NoFramePointerElim : 1; 79 80 /// DisableFramePointerElim - This returns true if frame pointer elimination 81 /// optimization should be disabled for the given machine function. 82 bool DisableFramePointerElim(const MachineFunction &MF) const; 83 84 /// LessPreciseFPMAD - This flag is enabled when the 85 /// -enable-fp-mad is specified on the command line. When this flag is off 86 /// (the default), the code generator is not allowed to generate mad 87 /// (multiply add) if the result is "less precise" than doing those 88 /// operations individually. 89 unsigned LessPreciseFPMADOption : 1; 90 bool LessPreciseFPMAD() const; 91 92 /// UnsafeFPMath - This flag is enabled when the 93 /// -enable-unsafe-fp-math flag is specified on the command line. When 94 /// this flag is off (the default), the code generator is not allowed to 95 /// produce results that are "less precise" than IEEE allows. This includes 96 /// use of X86 instructions like FSIN and FCOS instead of libcalls. 97 /// UnsafeFPMath implies LessPreciseFPMAD. 98 unsigned UnsafeFPMath : 1; 99 100 /// NoInfsFPMath - This flag is enabled when the 101 /// -enable-no-infs-fp-math flag is specified on the command line. When 102 /// this flag is off (the default), the code generator is not allowed to 103 /// assume the FP arithmetic arguments and results are never +-Infs. 104 unsigned NoInfsFPMath : 1; 105 106 /// NoNaNsFPMath - This flag is enabled when the 107 /// -enable-no-nans-fp-math flag is specified on the command line. When 108 /// this flag is off (the default), the code generator is not allowed to 109 /// assume the FP arithmetic arguments and results are never NaNs. 110 unsigned NoNaNsFPMath : 1; 111 112 /// HonorSignDependentRoundingFPMath - This returns true when the 113 /// -enable-sign-dependent-rounding-fp-math is specified. If this returns 114 /// false (the default), the code generator is allowed to assume that the 115 /// rounding behavior is the default (round-to-zero for all floating point 116 /// to integer conversions, and round-to-nearest for all other arithmetic 117 /// truncations). If this is enabled (set to true), the code generator must 118 /// assume that the rounding mode may dynamically change. 119 unsigned HonorSignDependentRoundingFPMathOption : 1; 120 bool HonorSignDependentRoundingFPMath() const; 121 122 /// UseSoftFloat - This flag is enabled when the -soft-float flag is 123 /// specified on the command line. When this flag is on, the code generator 124 /// will generate libcalls to the software floating point library instead of 125 /// target FP instructions. 126 unsigned UseSoftFloat : 1; 127 128 /// NoZerosInBSS - By default some codegens place zero-initialized data to 129 /// .bss section. This flag disables such behaviour (necessary, e.g. for 130 /// crt*.o compiling). 131 unsigned NoZerosInBSS : 1; 132 133 /// JITEmitDebugInfo - This flag indicates that the JIT should try to emit 134 /// debug information and notify a debugger about it. 135 unsigned JITEmitDebugInfo : 1; 136 137 /// JITEmitDebugInfoToDisk - This flag indicates that the JIT should write 138 /// the object files generated by the JITEmitDebugInfo flag to disk. This 139 /// flag is hidden and is only for debugging the debug info. 140 unsigned JITEmitDebugInfoToDisk : 1; 141 142 /// GuaranteedTailCallOpt - This flag is enabled when -tailcallopt is 143 /// specified on the commandline. When the flag is on, participating targets 144 /// will perform tail call optimization on all calls which use the fastcc 145 /// calling convention and which satisfy certain target-independent 146 /// criteria (being at the end of a function, having the same return type 147 /// as their parent function, etc.), using an alternate ABI if necessary. 148 unsigned GuaranteedTailCallOpt : 1; 149 150 /// DisableTailCalls - This flag controls whether we will use tail calls. 151 /// Disabling them may be useful to maintain a correct call stack. 152 unsigned DisableTailCalls : 1; 153 154 /// StackAlignmentOverride - Override default stack alignment for target. 155 unsigned StackAlignmentOverride; 156 157 /// EnableFastISel - This flag enables fast-path instruction selection 158 /// which trades away generated code quality in favor of reducing 159 /// compile time. 160 unsigned EnableFastISel : 1; 161 162 /// PositionIndependentExecutable - This flag indicates whether the code 163 /// will eventually be linked into a single executable, despite the PIC 164 /// relocation model being in use. It's value is undefined (and irrelevant) 165 /// if the relocation model is anything other than PIC. 166 unsigned PositionIndependentExecutable : 1; 167 168 /// UseInitArray - Use .init_array instead of .ctors for static 169 /// constructors. 170 unsigned UseInitArray : 1; 171 172 /// Disable the integrated assembler. 173 unsigned DisableIntegratedAS : 1; 174 175 /// Compress DWARF debug sections. 176 unsigned CompressDebugSections : 1; 177 178 /// Emit functions into separate sections. 179 unsigned FunctionSections : 1; 180 181 /// Emit data into separate sections. 182 unsigned DataSections : 1; 183 184 /// Emit target-specific trap instruction for 'unreachable' IR instructions. 185 unsigned TrapUnreachable : 1; 186 187 /// getTrapFunctionName - If this returns a non-empty string, this means 188 /// isel should lower Intrinsic::trap to a call to the specified function 189 /// name instead of an ISD::TRAP node. 190 std::string TrapFuncName; 191 StringRef getTrapFunctionName() const; 192 193 /// FloatABIType - This setting is set by -float-abi=xxx option is specfied 194 /// on the command line. This setting may either be Default, Soft, or Hard. 195 /// Default selects the target's default behavior. Soft selects the ABI for 196 /// UseSoftFloat, but does not indicate that FP hardware may not be used. 197 /// Such a combination is unfortunately popular (e.g. arm-apple-darwin). 198 /// Hard presumes that the normal FP ABI is used. 199 FloatABI::ABIType FloatABIType; 200 201 /// AllowFPOpFusion - This flag is set by the -fuse-fp-ops=xxx option. 202 /// This controls the creation of fused FP ops that store intermediate 203 /// results in higher precision than IEEE allows (E.g. FMAs). 204 /// 205 /// Fast mode - allows formation of fused FP ops whenever they're 206 /// profitable. 207 /// Standard mode - allow fusion only for 'blessed' FP ops. At present the 208 /// only blessed op is the fmuladd intrinsic. In the future more blessed ops 209 /// may be added. 210 /// Strict mode - allow fusion only if/when it can be proven that the excess 211 /// precision won't effect the result. 212 /// 213 /// Note: This option only controls formation of fused ops by the 214 /// optimizers. Fused operations that are explicitly specified (e.g. FMA 215 /// via the llvm.fma.* intrinsic) will always be honored, regardless of 216 /// the value of this option. 217 FPOpFusion::FPOpFusionMode AllowFPOpFusion; 218 219 /// JTType - This flag specifies the type of jump-instruction table to 220 /// create for functions that have the jumptable attribute. 221 JumpTable::JumpTableType JTType; 222 223 /// Machine level options. 224 MCTargetOptions MCOptions; 225 }; 226 227 // Comparison operators: 228 229 230 inline bool operator==(const TargetOptions &LHS, 231 const TargetOptions &RHS) { 232 #define ARE_EQUAL(X) LHS.X == RHS.X 233 return 234 ARE_EQUAL(UnsafeFPMath) && 235 ARE_EQUAL(NoInfsFPMath) && 236 ARE_EQUAL(NoNaNsFPMath) && 237 ARE_EQUAL(HonorSignDependentRoundingFPMathOption) && 238 ARE_EQUAL(UseSoftFloat) && 239 ARE_EQUAL(NoZerosInBSS) && 240 ARE_EQUAL(JITEmitDebugInfo) && 241 ARE_EQUAL(JITEmitDebugInfoToDisk) && 242 ARE_EQUAL(GuaranteedTailCallOpt) && 243 ARE_EQUAL(DisableTailCalls) && 244 ARE_EQUAL(StackAlignmentOverride) && 245 ARE_EQUAL(EnableFastISel) && 246 ARE_EQUAL(PositionIndependentExecutable) && 247 ARE_EQUAL(UseInitArray) && 248 ARE_EQUAL(TrapUnreachable) && 249 ARE_EQUAL(TrapFuncName) && 250 ARE_EQUAL(FloatABIType) && 251 ARE_EQUAL(AllowFPOpFusion) && 252 ARE_EQUAL(MCOptions); 253 #undef ARE_EQUAL 254 } 255 256 inline bool operator!=(const TargetOptions &LHS, 257 const TargetOptions &RHS) { 258 return !(LHS == RHS); 259 } 260 261 } // End llvm namespace 262 263 #endif 264
