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 namespace llvm { 19 class MachineFunction; 20 21 // Possible float ABI settings. Used with FloatABIType in TargetOptions.h. 22 namespace FloatABI { 23 enum ABIType { 24 Default, // Target-specific (either soft of hard depending on triple, etc). 25 Soft, // Soft float. 26 Hard // Hard float. 27 }; 28 } 29 30 /// PrintMachineCode - This flag is enabled when the -print-machineinstrs 31 /// option is specified on the command line, and should enable debugging 32 /// output from the code generator. 33 extern bool PrintMachineCode; 34 35 /// NoFramePointerElim - This flag is enabled when the -disable-fp-elim is 36 /// specified on the command line. If the target supports the frame pointer 37 /// elimination optimization, this option should disable it. 38 extern bool NoFramePointerElim; 39 40 /// NoFramePointerElimNonLeaf - This flag is enabled when the 41 /// -disable-non-leaf-fp-elim is specified on the command line. If the target 42 /// supports the frame pointer elimination optimization, this option should 43 /// disable it for non-leaf functions. 44 extern bool NoFramePointerElimNonLeaf; 45 46 /// DisableFramePointerElim - This returns true if frame pointer elimination 47 /// optimization should be disabled for the given machine function. 48 extern bool DisableFramePointerElim(const MachineFunction &MF); 49 50 /// LessPreciseFPMAD - This flag is enabled when the 51 /// -enable-fp-mad is specified on the command line. When this flag is off 52 /// (the default), the code generator is not allowed to generate mad 53 /// (multiply add) if the result is "less precise" than doing those operations 54 /// individually. 55 extern bool LessPreciseFPMADOption; 56 extern bool LessPreciseFPMAD(); 57 58 /// NoExcessFPPrecision - This flag is enabled when the 59 /// -disable-excess-fp-precision flag is specified on the command line. When 60 /// this flag is off (the default), the code generator is allowed to produce 61 /// results that are "more precise" than IEEE allows. This includes use of 62 /// FMA-like operations and use of the X86 FP registers without rounding all 63 /// over the place. 64 extern bool NoExcessFPPrecision; 65 66 /// UnsafeFPMath - This flag is enabled when the 67 /// -enable-unsafe-fp-math flag is specified on the command line. When 68 /// this flag is off (the default), the code generator is not allowed to 69 /// produce results that are "less precise" than IEEE allows. This includes 70 /// use of X86 instructions like FSIN and FCOS instead of libcalls. 71 /// UnsafeFPMath implies LessPreciseFPMAD. 72 extern bool UnsafeFPMath; 73 74 /// NoInfsFPMath - This flag is enabled when the 75 /// -enable-no-infs-fp-math flag is specified on the command line. When 76 /// this flag is off (the default), the code generator is not allowed to 77 /// assume the FP arithmetic arguments and results are never +-Infs. 78 extern bool NoInfsFPMath; 79 80 /// NoNaNsFPMath - This flag is enabled when the 81 /// -enable-no-nans-fp-math flag is specified on the command line. When 82 /// this flag is off (the default), the code generator is not allowed to 83 /// assume the FP arithmetic arguments and results are never NaNs. 84 extern bool NoNaNsFPMath; 85 86 /// HonorSignDependentRoundingFPMath - This returns true when the 87 /// -enable-sign-dependent-rounding-fp-math is specified. If this returns 88 /// false (the default), the code generator is allowed to assume that the 89 /// rounding behavior is the default (round-to-zero for all floating point to 90 /// integer conversions, and round-to-nearest for all other arithmetic 91 /// truncations). If this is enabled (set to true), the code generator must 92 /// assume that the rounding mode may dynamically change. 93 extern bool HonorSignDependentRoundingFPMathOption; 94 extern bool HonorSignDependentRoundingFPMath(); 95 96 /// UseSoftFloat - This flag is enabled when the -soft-float flag is specified 97 /// on the command line. When this flag is on, the code generator will 98 /// generate libcalls to the software floating point library instead of 99 /// target FP instructions. 100 extern bool UseSoftFloat; 101 102 /// FloatABIType - This setting is set by -float-abi=xxx option is specfied 103 /// on the command line. This setting may either be Default, Soft, or Hard. 104 /// Default selects the target's default behavior. Soft selects the ABI for 105 /// UseSoftFloat, but does not inidcate that FP hardware may not be used. 106 /// Such a combination is unfortunately popular (e.g. arm-apple-darwin). 107 /// Hard presumes that the normal FP ABI is used. 108 extern FloatABI::ABIType FloatABIType; 109 110 /// NoZerosInBSS - By default some codegens place zero-initialized data to 111 /// .bss section. This flag disables such behaviour (necessary, e.g. for 112 /// crt*.o compiling). 113 extern bool NoZerosInBSS; 114 115 /// JITExceptionHandling - This flag indicates that the JIT should emit 116 /// exception handling information. 117 extern bool JITExceptionHandling; 118 119 /// JITEmitDebugInfo - This flag indicates that the JIT should try to emit 120 /// debug information and notify a debugger about it. 121 extern bool JITEmitDebugInfo; 122 123 /// JITEmitDebugInfoToDisk - This flag indicates that the JIT should write 124 /// the object files generated by the JITEmitDebugInfo flag to disk. This 125 /// flag is hidden and is only for debugging the debug info. 126 extern bool JITEmitDebugInfoToDisk; 127 128 /// GuaranteedTailCallOpt - This flag is enabled when -tailcallopt is 129 /// specified on the commandline. When the flag is on, participating targets 130 /// will perform tail call optimization on all calls which use the fastcc 131 /// calling convention and which satisfy certain target-independent 132 /// criteria (being at the end of a function, having the same return type 133 /// as their parent function, etc.), using an alternate ABI if necessary. 134 extern bool GuaranteedTailCallOpt; 135 136 /// StackAlignmentOverride - Override default stack alignment for target. 137 extern unsigned StackAlignmentOverride; 138 139 /// RealignStack - This flag indicates whether the stack should be 140 /// automatically realigned, if needed. 141 extern bool RealignStack; 142 143 /// DisableJumpTables - This flag indicates jump tables should not be 144 /// generated. 145 extern bool DisableJumpTables; 146 147 /// EnableFastISel - This flag enables fast-path instruction selection 148 /// which trades away generated code quality in favor of reducing 149 /// compile time. 150 extern bool EnableFastISel; 151 152 /// StrongPHIElim - This flag enables more aggressive PHI elimination 153 /// wth earlier copy coalescing. 154 extern bool StrongPHIElim; 155 156 /// getTrapFunctionName - If this returns a non-empty string, this means isel 157 /// should lower Intrinsic::trap to a call to the specified function name 158 /// instead of an ISD::TRAP node. 159 extern StringRef getTrapFunctionName(); 160 161 extern bool EnableSegmentedStacks; 162 163 } // End llvm namespace 164 165 #endif 166