mips.opt revision 1.9
1; Options for the MIPS port of the compiler 2; 3; Copyright (C) 2005-2018 Free Software Foundation, Inc. 4; 5; This file is part of GCC. 6; 7; GCC is free software; you can redistribute it and/or modify it under 8; the terms of the GNU General Public License as published by the Free 9; Software Foundation; either version 3, or (at your option) any later 10; version. 11; 12; GCC is distributed in the hope that it will be useful, but WITHOUT 13; ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 14; or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public 15; License for more details. 16; 17; You should have received a copy of the GNU General Public License 18; along with GCC; see the file COPYING3. If not see 19; <http://www.gnu.org/licenses/>. 20 21HeaderInclude 22config/mips/mips-opts.h 23 24EB 25Driver 26 27EL 28Driver 29 30mabi= 31Target RejectNegative Joined Enum(mips_abi) Var(mips_abi) Init(MIPS_ABI_DEFAULT) 32-mabi=ABI Generate code that conforms to the given ABI. 33 34Enum 35Name(mips_abi) Type(int) 36Known MIPS ABIs (for use with the -mabi= option): 37 38EnumValue 39Enum(mips_abi) String(32) Value(ABI_32) 40 41EnumValue 42Enum(mips_abi) String(o64) Value(ABI_O64) 43 44EnumValue 45Enum(mips_abi) String(n32) Value(ABI_N32) 46 47EnumValue 48Enum(mips_abi) String(64) Value(ABI_64) 49 50EnumValue 51Enum(mips_abi) String(eabi) Value(ABI_EABI) 52 53mabicalls 54Target Report Mask(ABICALLS) 55Generate code that can be used in SVR4-style dynamic objects. 56 57mmad 58Target Report Var(TARGET_MAD) 59Use PMC-style 'mad' instructions. 60 61mimadd 62Target Report Mask(IMADD) 63Use integer madd/msub instructions. 64 65march= 66Target RejectNegative Joined Var(mips_arch_option) ToLower Enum(mips_arch_opt_value) 67-march=ISA Generate code for the given ISA. 68 69mbranch-cost= 70Target RejectNegative Joined UInteger Var(mips_branch_cost) 71-mbranch-cost=COST Set the cost of branches to roughly COST instructions. 72 73mbranch-likely 74Target Report Mask(BRANCHLIKELY) 75Use Branch Likely instructions, overriding the architecture default. 76 77mflip-mips16 78Target Report Var(TARGET_FLIP_MIPS16) 79Switch on/off MIPS16 ASE on alternating functions for compiler testing. 80 81mcheck-zero-division 82Target Report Mask(CHECK_ZERO_DIV) 83Trap on integer divide by zero. 84 85mcode-readable= 86Target RejectNegative Joined Enum(mips_code_readable_setting) Var(mips_code_readable) Init(CODE_READABLE_YES) 87-mcode-readable=SETTING Specify when instructions are allowed to access code. 88 89Enum 90Name(mips_code_readable_setting) Type(enum mips_code_readable_setting) 91Valid arguments to -mcode-readable=: 92 93EnumValue 94Enum(mips_code_readable_setting) String(yes) Value(CODE_READABLE_YES) 95 96EnumValue 97Enum(mips_code_readable_setting) String(pcrel) Value(CODE_READABLE_PCREL) 98 99EnumValue 100Enum(mips_code_readable_setting) String(no) Value(CODE_READABLE_NO) 101 102mdivide-breaks 103Target Report RejectNegative Mask(DIVIDE_BREAKS) 104Use branch-and-break sequences to check for integer divide by zero. 105 106mdivide-traps 107Target Report RejectNegative InverseMask(DIVIDE_BREAKS, DIVIDE_TRAPS) 108Use trap instructions to check for integer divide by zero. 109 110mdmx 111Target Report RejectNegative Var(TARGET_MDMX) 112Allow the use of MDMX instructions. 113 114mdouble-float 115Target Report RejectNegative InverseMask(SINGLE_FLOAT, DOUBLE_FLOAT) 116Allow hardware floating-point instructions to cover both 32-bit and 64-bit operations. 117 118mdsp 119Target Report Var(TARGET_DSP) 120Use MIPS-DSP instructions. 121 122mdspr2 123Target Report Var(TARGET_DSPR2) 124Use MIPS-DSP REV 2 instructions. 125 126mdebug 127Target Var(TARGET_DEBUG_MODE) Undocumented 128 129mdebugd 130Target Var(TARGET_DEBUG_D_MODE) Undocumented 131 132meb 133Target Report RejectNegative Mask(BIG_ENDIAN) 134Use big-endian byte order. 135 136mel 137Target Report RejectNegative InverseMask(BIG_ENDIAN, LITTLE_ENDIAN) 138Use little-endian byte order. 139 140membedded-data 141Target Report Var(TARGET_EMBEDDED_DATA) 142Use ROM instead of RAM. 143 144meva 145Target Report Var(TARGET_EVA) 146Use Enhanced Virtual Addressing instructions. 147 148mexplicit-relocs 149Target Report Mask(EXPLICIT_RELOCS) 150Use NewABI-style %reloc() assembly operators. 151 152mextern-sdata 153Target Report Var(TARGET_EXTERN_SDATA) Init(1) 154Use -G for data that is not defined by the current object. 155 156mfix-24k 157Target Report Var(TARGET_FIX_24K) 158Work around certain 24K errata. 159 160mfix-r4000 161Target Report Mask(FIX_R4000) 162Work around certain R4000 errata. 163 164mfix-r4400 165Target Report Mask(FIX_R4400) 166Work around certain R4400 errata. 167 168mfix-rm7000 169Target Report Var(TARGET_FIX_RM7000) 170Work around certain RM7000 errata. 171 172mfix-r10000 173Target Report Mask(FIX_R10000) 174Work around certain R10000 errata. 175 176mfix-sb1 177Target Report Var(TARGET_FIX_SB1) 178Work around errata for early SB-1 revision 2 cores. 179 180mfix-vr4120 181Target Report Var(TARGET_FIX_VR4120) 182Work around certain VR4120 errata. 183 184mfix-vr4130 185Target Report Var(TARGET_FIX_VR4130) 186Work around VR4130 mflo/mfhi errata. 187 188mfix4300 189Target Report Var(TARGET_4300_MUL_FIX) 190Work around an early 4300 hardware bug. 191 192mfp-exceptions 193Target Report Var(TARGET_FP_EXCEPTIONS) Init(1) 194FP exceptions are enabled. 195 196mfp32 197Target Report RejectNegative InverseMask(FLOAT64) 198Use 32-bit floating-point registers. 199 200mfpxx 201Target Report RejectNegative Mask(FLOATXX) 202Conform to the o32 FPXX ABI. 203 204mfp64 205Target Report RejectNegative Mask(FLOAT64) 206Use 64-bit floating-point registers. 207 208mflush-func= 209Target RejectNegative Joined Var(mips_cache_flush_func) Init(CACHE_FLUSH_FUNC) 210-mflush-func=FUNC Use FUNC to flush the cache before calling stack trampolines. 211 212mabs= 213Target RejectNegative Joined Enum(mips_ieee_754_value) Var(mips_abs) Init(MIPS_IEEE_754_DEFAULT) 214-mabs=MODE Select the IEEE 754 ABS/NEG instruction execution mode. 215 216mnan= 217Target RejectNegative Joined Enum(mips_ieee_754_value) Var(mips_nan) Init(MIPS_IEEE_754_DEFAULT) 218-mnan=ENCODING Select the IEEE 754 NaN data encoding. 219 220Enum 221Name(mips_ieee_754_value) Type(int) 222Known MIPS IEEE 754 settings (for use with the -mabs= and -mnan= options): 223 224EnumValue 225Enum(mips_ieee_754_value) String(2008) Value(MIPS_IEEE_754_2008) 226 227EnumValue 228Enum(mips_ieee_754_value) String(legacy) Value(MIPS_IEEE_754_LEGACY) 229 230mgp32 231Target Report RejectNegative InverseMask(64BIT) 232Use 32-bit general registers. 233 234mgp64 235Target Report RejectNegative Mask(64BIT) 236Use 64-bit general registers. 237 238mgpopt 239Target Report Var(TARGET_GPOPT) Init(1) 240Use GP-relative addressing to access small data. 241 242mplt 243Target Report Var(TARGET_PLT) 244When generating -mabicalls code, allow executables to use PLTs and copy relocations. 245 246mhard-float 247Target Report RejectNegative InverseMask(SOFT_FLOAT_ABI, HARD_FLOAT_ABI) 248Allow the use of hardware floating-point ABI and instructions. 249 250minterlink-compressed 251Target Report Var(TARGET_INTERLINK_COMPRESSED) Init(0) 252Generate code that is link-compatible with MIPS16 and microMIPS code. 253 254minterlink-mips16 255Target Report Var(TARGET_INTERLINK_COMPRESSED) Init(0) 256An alias for minterlink-compressed provided for backward-compatibility. 257 258mips 259Target RejectNegative Joined ToLower Enum(mips_mips_opt_value) Var(mips_isa_option) 260-mipsN Generate code for ISA level N. 261 262mips16 263Target Report RejectNegative Mask(MIPS16) 264Generate MIPS16 code. 265 266mips3d 267Target Report RejectNegative Var(TARGET_MIPS3D) 268Use MIPS-3D instructions. 269 270mllsc 271Target Report Mask(LLSC) 272Use ll, sc and sync instructions. 273 274mlocal-sdata 275Target Report Var(TARGET_LOCAL_SDATA) Init(1) 276Use -G for object-local data. 277 278mlong-calls 279Target Report Var(TARGET_LONG_CALLS) 280Use indirect calls. 281 282mlong32 283Target Report RejectNegative InverseMask(LONG64, LONG32) 284Use a 32-bit long type. 285 286mlong64 287Target Report RejectNegative Mask(LONG64) 288Use a 64-bit long type. 289 290mmcount-ra-address 291Target Report Var(TARGET_MCOUNT_RA_ADDRESS) 292Pass the address of the ra save location to _mcount in $12. 293 294mmemcpy 295Target Report Mask(MEMCPY) 296Don't optimize block moves. 297 298mmicromips 299Target Report Mask(MICROMIPS) 300Use microMIPS instructions. 301 302mmsa 303Target Report Var(TARGET_MSA) 304Use MIPS MSA Extension instructions. 305 306mmt 307Target Report Var(TARGET_MT) 308Allow the use of MT instructions. 309 310mno-float 311Target Report RejectNegative Var(TARGET_NO_FLOAT) Condition(TARGET_SUPPORTS_NO_FLOAT) 312Prevent the use of all floating-point operations. 313 314mmcu 315Target Report Var(TARGET_MCU) 316Use MCU instructions. 317 318mno-flush-func 319Target RejectNegative 320Do not use a cache-flushing function before calling stack trampolines. 321 322mno-mdmx 323Target Report RejectNegative Var(TARGET_MDMX, 0) 324Do not use MDMX instructions. 325 326mno-mips16 327Target Report RejectNegative InverseMask(MIPS16) 328Generate normal-mode code. 329 330mno-mips3d 331Target Report RejectNegative Var(TARGET_MIPS3D, 0) 332Do not use MIPS-3D instructions. 333 334mpaired-single 335Target Report Mask(PAIRED_SINGLE_FLOAT) 336Use paired-single floating-point instructions. 337 338mr10k-cache-barrier= 339Target Joined RejectNegative Enum(mips_r10k_cache_barrier_setting) Var(mips_r10k_cache_barrier) Init(R10K_CACHE_BARRIER_NONE) 340-mr10k-cache-barrier=SETTING Specify when r10k cache barriers should be inserted. 341 342Enum 343Name(mips_r10k_cache_barrier_setting) Type(enum mips_r10k_cache_barrier_setting) 344Valid arguments to -mr10k-cache-barrier=: 345 346EnumValue 347Enum(mips_r10k_cache_barrier_setting) String(load-store) Value(R10K_CACHE_BARRIER_LOAD_STORE) 348 349EnumValue 350Enum(mips_r10k_cache_barrier_setting) String(store) Value(R10K_CACHE_BARRIER_STORE) 351 352EnumValue 353Enum(mips_r10k_cache_barrier_setting) String(none) Value(R10K_CACHE_BARRIER_NONE) 354 355mrelax-pic-calls 356Target Report Mask(RELAX_PIC_CALLS) 357Try to allow the linker to turn PIC calls into direct calls. 358 359mshared 360Target Report Var(TARGET_SHARED) Init(1) 361When generating -mabicalls code, make the code suitable for use in shared libraries. 362 363msingle-float 364Target Report RejectNegative Mask(SINGLE_FLOAT) 365Restrict the use of hardware floating-point instructions to 32-bit operations. 366 367msmartmips 368Target Report Mask(SMARTMIPS) 369Use SmartMIPS instructions. 370 371msoft-float 372Target Report RejectNegative Mask(SOFT_FLOAT_ABI) 373Prevent the use of all hardware floating-point instructions. 374 375msplit-addresses 376Target Report Mask(SPLIT_ADDRESSES) 377Optimize lui/addiu address loads. 378 379msym32 380Target Report Var(TARGET_SYM32) 381Assume all symbols have 32-bit values. 382 383msynci 384Target Report Mask(SYNCI) 385Use synci instruction to invalidate i-cache. 386 387mlra 388Target Report Var(mips_lra_flag) Init(1) Save 389Use LRA instead of reload. 390 391mlxc1-sxc1 392Target Report Var(mips_lxc1_sxc1) Init(1) 393Use lwxc1/swxc1/ldxc1/sdxc1 instructions where applicable. 394 395mmadd4 396Target Report Var(mips_madd4) Init(1) 397Use 4-operand madd.s/madd.d and related instructions where applicable. 398 399mtune= 400Target RejectNegative Joined Var(mips_tune_option) ToLower Enum(mips_arch_opt_value) 401-mtune=PROCESSOR Optimize the output for PROCESSOR. 402 403muninit-const-in-rodata 404Target Report Var(TARGET_UNINIT_CONST_IN_RODATA) 405Put uninitialized constants in ROM (needs -membedded-data). 406 407mvirt 408Target Report Var(TARGET_VIRT) 409Use Virtualization (VZ) instructions. 410 411mxpa 412Target Report Var(TARGET_XPA) 413Use eXtended Physical Address (XPA) instructions. 414 415mvr4130-align 416Target Report Mask(VR4130_ALIGN) 417Perform VR4130-specific alignment optimizations. 418 419mxgot 420Target Report Var(TARGET_XGOT) 421Lift restrictions on GOT size. 422 423modd-spreg 424Target Report Mask(ODD_SPREG) 425Enable use of odd-numbered single-precision registers. 426 427mframe-header-opt 428Target Report Var(flag_frame_header_optimization) Optimization 429Optimize frame header. 430 431noasmopt 432Driver 433 434mload-store-pairs 435Target Report Var(TARGET_LOAD_STORE_PAIRS) Init(1) 436Enable load/store bonding. 437 438mcompact-branches= 439Target RejectNegative JoinedOrMissing Var(mips_cb) Report Enum(mips_cb_setting) Init(MIPS_CB_OPTIMAL) 440Specify the compact branch usage policy. 441 442Enum 443Name(mips_cb_setting) Type(enum mips_cb_setting) 444Policies available for use with -mcompact-branches=: 445 446EnumValue 447Enum(mips_cb_setting) String(never) Value(MIPS_CB_NEVER) 448 449EnumValue 450Enum(mips_cb_setting) String(optimal) Value(MIPS_CB_OPTIMAL) 451 452EnumValue 453Enum(mips_cb_setting) String(always) Value(MIPS_CB_ALWAYS) 454