xref: /netbsd-src/external/gpl3/gcc.old/dist/gcc/config/rs6000/rs6000.opt (revision ae082add65442546470c0ba499a860ee89eed305)
1; Options for the rs6000 port of the compiler
2;
3; Copyright (C) 2005-2019 Free Software Foundation, Inc.
4; Contributed by Aldy Hernandez <aldy@quesejoda.com>.
5;
6; This file is part of GCC.
7;
8; GCC is free software; you can redistribute it and/or modify it under
9; the terms of the GNU General Public License as published by the Free
10; Software Foundation; either version 3, or (at your option) any later
11; version.
12;
13; GCC is distributed in the hope that it will be useful, but WITHOUT
14; ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15; or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
16; License for more details.
17;
18; You should have received a copy of the GNU General Public License
19; along with GCC; see the file COPYING3.  If not see
20; <http://www.gnu.org/licenses/>.
21
22HeaderInclude
23config/rs6000/rs6000-opts.h
24
25;; ISA flag bits (on/off)
26Variable
27HOST_WIDE_INT rs6000_isa_flags = TARGET_DEFAULT
28
29TargetSave
30HOST_WIDE_INT x_rs6000_isa_flags
31
32;; Miscellaneous flag bits that were set explicitly by the user
33Variable
34HOST_WIDE_INT rs6000_isa_flags_explicit
35
36TargetSave
37HOST_WIDE_INT x_rs6000_isa_flags_explicit
38
39;; Current processor
40TargetVariable
41enum processor_type rs6000_cpu = PROCESSOR_PPC603
42
43;; Current tuning
44TargetVariable
45enum processor_type rs6000_tune = PROCESSOR_PPC603
46
47;; Always emit branch hint bits.
48TargetVariable
49unsigned char rs6000_always_hint
50
51;; Schedule instructions for group formation.
52TargetVariable
53unsigned char rs6000_sched_groups
54
55;; Align branch targets.
56TargetVariable
57unsigned char rs6000_align_branch_targets
58
59;; Support for -msched-costly-dep option.
60TargetVariable
61enum rs6000_dependence_cost rs6000_sched_costly_dep = no_dep_costly
62
63;; Support for -minsert-sched-nops option.
64TargetVariable
65enum rs6000_nop_insertion rs6000_sched_insert_nops = sched_finish_none
66
67;; Non-zero to allow overriding loop alignment.
68TargetVariable
69unsigned char can_override_loop_align
70
71;; Which small data model to use (for System V targets only)
72TargetVariable
73enum rs6000_sdata_type rs6000_sdata = SDATA_DATA
74
75;; Bit size of immediate TLS offsets and string from which it is decoded.
76TargetVariable
77int rs6000_tls_size = 32
78
79;; ABI enumeration available for subtarget to use.
80TargetVariable
81enum rs6000_abi rs6000_current_abi = ABI_NONE
82
83;; Type of traceback to use.
84TargetVariable
85enum rs6000_traceback_type rs6000_traceback = traceback_default
86
87;; Control alignment for fields within structures.
88TargetVariable
89unsigned char rs6000_alignment_flags
90
91;; Code model for 64-bit linux.
92TargetVariable
93enum rs6000_cmodel rs6000_current_cmodel = CMODEL_SMALL
94
95;; What type of reciprocal estimation instructions to generate
96TargetVariable
97unsigned int rs6000_recip_control
98
99;; Mask of what builtin functions are allowed
100TargetVariable
101HOST_WIDE_INT rs6000_builtin_mask
102
103;; Debug flags
104TargetVariable
105unsigned int rs6000_debug
106
107;; Whether to enable the -mfloat128 stuff without necessarily enabling the
108;; __float128 keyword.
109TargetSave
110unsigned char x_TARGET_FLOAT128_TYPE
111
112Variable
113unsigned char TARGET_FLOAT128_TYPE
114
115;; This option existed in the past, but now is always on.
116mpowerpc
117Target RejectNegative Undocumented Ignore
118
119mpowerpc64
120Target Report Mask(POWERPC64) Var(rs6000_isa_flags)
121Use PowerPC-64 instruction set.
122
123mpowerpc-gpopt
124Target Report Mask(PPC_GPOPT) Var(rs6000_isa_flags)
125Use PowerPC General Purpose group optional instructions.
126
127mpowerpc-gfxopt
128Target Report Mask(PPC_GFXOPT) Var(rs6000_isa_flags)
129Use PowerPC Graphics group optional instructions.
130
131mmfcrf
132Target Report Mask(MFCRF) Var(rs6000_isa_flags)
133Use PowerPC V2.01 single field mfcr instruction.
134
135mpopcntb
136Target Report Mask(POPCNTB) Var(rs6000_isa_flags)
137Use PowerPC V2.02 popcntb instruction.
138
139mfprnd
140Target Report Mask(FPRND) Var(rs6000_isa_flags)
141Use PowerPC V2.02 floating point rounding instructions.
142
143mcmpb
144Target Report Mask(CMPB) Var(rs6000_isa_flags)
145Use PowerPC V2.05 compare bytes instruction.
146
147mmfpgpr
148Target Report Mask(MFPGPR) Var(rs6000_isa_flags)
149Use extended PowerPC V2.05 move floating point to/from GPR instructions.
150
151maltivec
152Target Report Mask(ALTIVEC) Var(rs6000_isa_flags)
153Use AltiVec instructions.
154
155mfold-gimple
156Target Report Var(rs6000_fold_gimple) Init(1)
157Enable early gimple folding of builtins.
158
159mhard-dfp
160Target Report Mask(DFP) Var(rs6000_isa_flags)
161Use decimal floating point instructions.
162
163mmulhw
164Target Report Mask(MULHW) Var(rs6000_isa_flags)
165Use 4xx half-word multiply instructions.
166
167mdlmzb
168Target Report Mask(DLMZB) Var(rs6000_isa_flags)
169Use 4xx string-search dlmzb instruction.
170
171mmultiple
172Target Report Mask(MULTIPLE) Var(rs6000_isa_flags)
173Generate load/store multiple instructions.
174
175;; This option existed in the past, but now is always off.
176mno-string
177Target RejectNegative Undocumented Ignore
178
179mstring
180Target RejectNegative Undocumented Deprecated
181
182msoft-float
183Target Report RejectNegative Mask(SOFT_FLOAT) Var(rs6000_isa_flags)
184Do not use hardware floating point.
185
186mhard-float
187Target Report RejectNegative InverseMask(SOFT_FLOAT, HARD_FLOAT) Var(rs6000_isa_flags)
188Use hardware floating point.
189
190mpopcntd
191Target Report Mask(POPCNTD) Var(rs6000_isa_flags)
192Use PowerPC V2.06 popcntd instruction.
193
194mfriz
195Target Report Var(TARGET_FRIZ) Init(-1) Save
196Under -ffast-math, generate a FRIZ instruction for (double)(long long) conversions.
197
198mveclibabi=
199Target RejectNegative Joined Var(rs6000_veclibabi_name)
200Vector library ABI to use.
201
202mvsx
203Target Report Mask(VSX) Var(rs6000_isa_flags)
204Use vector/scalar (VSX) instructions.
205
206mvsx-align-128
207Target Undocumented Report Var(TARGET_VSX_ALIGN_128) Save
208; If -mvsx, set alignment to 128 bits instead of 32/64
209
210mallow-movmisalign
211Target Undocumented Var(TARGET_ALLOW_MOVMISALIGN) Init(-1) Save
212; Allow the movmisalign in DF/DI vectors
213
214mefficient-unaligned-vsx
215Target Undocumented Report Mask(EFFICIENT_UNALIGNED_VSX) Var(rs6000_isa_flags)
216; Consider unaligned VSX vector and fp accesses to be efficient
217
218msched-groups
219Target Undocumented Report Var(TARGET_SCHED_GROUPS) Init(-1) Save
220; Explicitly set rs6000_sched_groups
221
222malways-hint
223Target Undocumented Report Var(TARGET_ALWAYS_HINT) Init(-1) Save
224; Explicitly set rs6000_always_hint
225
226malign-branch-targets
227Target Undocumented Report Var(TARGET_ALIGN_BRANCH_TARGETS) Init(-1) Save
228; Explicitly set rs6000_align_branch_targets
229
230mno-update
231Target Report RejectNegative Mask(NO_UPDATE) Var(rs6000_isa_flags)
232Do not generate load/store with update instructions.
233
234mupdate
235Target Report RejectNegative InverseMask(NO_UPDATE, UPDATE) Var(rs6000_isa_flags)
236Generate load/store with update instructions.
237
238msingle-pic-base
239Target Report Var(TARGET_SINGLE_PIC_BASE) Init(0)
240Do not load the PIC register in function prologues.
241
242mavoid-indexed-addresses
243Target Report Var(TARGET_AVOID_XFORM) Init(-1) Save
244Avoid generation of indexed load/store instructions when possible.
245
246mtls-markers
247Target Report Var(tls_markers) Init(1) Save
248Mark __tls_get_addr calls with argument info.
249
250msched-epilog
251Target Undocumented Var(TARGET_SCHED_PROLOG) Init(1) Save
252
253msched-prolog
254Target Report Var(TARGET_SCHED_PROLOG) Save
255Schedule the start and end of the procedure.
256
257maix-struct-return
258Target Report RejectNegative Var(aix_struct_return) Save
259Return all structures in memory (AIX default).
260
261msvr4-struct-return
262Target Report RejectNegative Var(aix_struct_return,0) Save
263Return small structures in registers (SVR4 default).
264
265mxl-compat
266Target Report Var(TARGET_XL_COMPAT) Save
267Conform more closely to IBM XLC semantics.
268
269mrecip
270Target Report
271Generate software reciprocal divide and square root for better throughput.
272
273mrecip=
274Target Report RejectNegative Joined Var(rs6000_recip_name)
275Generate software reciprocal divide and square root for better throughput.
276
277mrecip-precision
278Target Report Mask(RECIP_PRECISION) Var(rs6000_isa_flags)
279Assume that the reciprocal estimate instructions provide more accuracy.
280
281mno-fp-in-toc
282Target Report RejectNegative Var(TARGET_NO_FP_IN_TOC) Save
283Do not place floating point constants in TOC.
284
285mfp-in-toc
286Target Report RejectNegative Var(TARGET_NO_FP_IN_TOC,0) Save
287Place floating point constants in TOC.
288
289mno-sum-in-toc
290Target RejectNegative Var(TARGET_NO_SUM_IN_TOC) Save
291Do not place symbol+offset constants in TOC.
292
293msum-in-toc
294Target RejectNegative Var(TARGET_NO_SUM_IN_TOC,0) Save
295Place symbol+offset constants in TOC.
296
297;  Output only one TOC entry per module.  Normally linking fails if
298;   there are more than 16K unique variables/constants in an executable.  With
299;   this option, linking fails only if there are more than 16K modules, or
300;   if there are more than 16K unique variables/constant in a single module.
301;
302;   This is at the cost of having 2 extra loads and one extra store per
303;   function, and one less allocable register.
304mminimal-toc
305Target Report Mask(MINIMAL_TOC) Var(rs6000_isa_flags)
306Use only one TOC entry per procedure.
307
308mfull-toc
309Target Report
310Put everything in the regular TOC.
311
312mvrsave
313Target Report Var(TARGET_ALTIVEC_VRSAVE) Save
314Generate VRSAVE instructions when generating AltiVec code.
315
316mvrsave=no
317Target RejectNegative Alias(mvrsave) NegativeAlias Warn(%<-mvrsave=no%> is deprecated; use %<-mno-vrsave%> instead)
318Deprecated option.  Use -mno-vrsave instead.
319
320mvrsave=yes
321Target RejectNegative Alias(mvrsave) Warn(%<-mvrsave=yes%> is deprecated; use %<-mvrsave%> instead)
322Deprecated option.  Use -mvrsave instead.
323
324mblock-move-inline-limit=
325Target Report Var(rs6000_block_move_inline_limit) Init(0) RejectNegative Joined UInteger Save
326Max number of bytes to move inline.
327
328mblock-compare-inline-limit=
329Target Report Var(rs6000_block_compare_inline_limit) Init(63) RejectNegative Joined UInteger Save
330Max number of bytes to compare without loops.
331
332mblock-compare-inline-loop-limit=
333Target Report Var(rs6000_block_compare_inline_loop_limit) Init(-1) RejectNegative Joined UInteger Save
334Max number of bytes to compare with loops.
335
336mstring-compare-inline-limit=
337Target Report Var(rs6000_string_compare_inline_limit) Init(64) RejectNegative Joined UInteger Save
338Max number of bytes to compare.
339
340misel
341Target Report Mask(ISEL) Var(rs6000_isa_flags)
342Generate isel instructions.
343
344mdebug=
345Target RejectNegative Joined
346-mdebug=	Enable debug output.
347
348mabi=altivec
349Target RejectNegative Var(rs6000_altivec_abi) Save
350Use the AltiVec ABI extensions.
351
352mabi=no-altivec
353Target RejectNegative Var(rs6000_altivec_abi, 0)
354Do not use the AltiVec ABI extensions.
355
356mabi=elfv1
357Target RejectNegative Var(rs6000_elf_abi, 1) Save
358Use the ELFv1 ABI.
359
360mabi=elfv2
361Target RejectNegative Var(rs6000_elf_abi, 2)
362Use the ELFv2 ABI.
363
364; These are here for testing during development only, do not document
365; in the manual please.
366
367; If we want Darwin's struct-by-value-in-regs ABI.
368mabi=d64
369Target RejectNegative Undocumented Warn(using darwin64 ABI) Var(rs6000_darwin64_abi) Save
370
371mabi=d32
372Target RejectNegative Undocumented Warn(using old darwin ABI) Var(rs6000_darwin64_abi, 0)
373
374mabi=ieeelongdouble
375Target RejectNegative Var(rs6000_ieeequad) Save
376
377mabi=ibmlongdouble
378Target RejectNegative Var(rs6000_ieeequad, 0)
379
380mcpu=
381Target RejectNegative Joined Var(rs6000_cpu_index) Init(-1) Enum(rs6000_cpu_opt_value) Save
382-mcpu=	Use features of and schedule code for given CPU.
383
384mtune=
385Target RejectNegative Joined Var(rs6000_tune_index) Init(-1) Enum(rs6000_cpu_opt_value) Save
386-mtune=	Schedule code for given CPU.
387
388; Only for use in the testsuite.  This simply overrides -mcpu=.  With older
389; versions of Dejagnu the command line arguments you set in RUNTESTFLAGS
390; override those set in the testcases; with this option, the testcase will
391; always win.
392mdejagnu-cpu=
393Target Undocumented RejectNegative Joined Var(rs6000_dejagnu_cpu_index) Init(-1) Enum(rs6000_cpu_opt_value) Save
394
395mtraceback=
396Target RejectNegative Joined Enum(rs6000_traceback_type) Var(rs6000_traceback)
397-mtraceback=[full,part,no]	Select type of traceback table.
398
399Enum
400Name(rs6000_traceback_type) Type(enum rs6000_traceback_type)
401
402EnumValue
403Enum(rs6000_traceback_type) String(full) Value(traceback_full)
404
405EnumValue
406Enum(rs6000_traceback_type) String(part) Value(traceback_part)
407
408EnumValue
409Enum(rs6000_traceback_type) String(no) Value(traceback_none)
410
411mlongcall
412Target Report Var(rs6000_default_long_calls) Save
413Avoid all range limits on call instructions.
414
415; This option existed in the past, but now is always on.
416mgen-cell-microcode
417Target RejectNegative Undocumented Ignore
418
419mwarn-altivec-long
420Target Var(rs6000_warn_altivec_long) Init(1) Save
421Warn about deprecated 'vector long ...' AltiVec type usage.
422
423mlong-double-
424Target RejectNegative Joined UInteger Var(rs6000_long_double_type_size) Save
425-mlong-double-[64,128]	Specify size of long double.
426
427; This option existed in the past, but now is always on.
428mlra
429Target RejectNegative Undocumented Ignore
430
431msched-costly-dep=
432Target RejectNegative Joined Var(rs6000_sched_costly_dep_str)
433Determine which dependences between insns are considered costly.
434
435minsert-sched-nops=
436Target RejectNegative Joined Var(rs6000_sched_insert_nops_str)
437Specify which post scheduling nop insertion scheme to apply.
438
439malign-
440Target RejectNegative Joined Enum(rs6000_alignment_flags) Var(rs6000_alignment_flags)
441Specify alignment of structure fields default/natural.
442
443Enum
444Name(rs6000_alignment_flags) Type(unsigned char)
445Valid arguments to -malign-:
446
447EnumValue
448Enum(rs6000_alignment_flags) String(power) Value(MASK_ALIGN_POWER)
449
450EnumValue
451Enum(rs6000_alignment_flags) String(natural) Value(MASK_ALIGN_NATURAL)
452
453mprioritize-restricted-insns=
454Target RejectNegative Joined UInteger Var(rs6000_sched_restricted_insns_priority) Save
455Specify scheduling priority for dispatch slot restricted insns.
456
457mpointers-to-nested-functions
458Target Report Var(TARGET_POINTERS_TO_NESTED_FUNCTIONS) Init(1) Save
459Use r11 to hold the static link in calls to functions via pointers.
460
461msave-toc-indirect
462Target Report Mask(SAVE_TOC_INDIRECT) Var(rs6000_isa_flags)
463Save the TOC in the prologue for indirect calls rather than inline.
464
465; This option existed in the past, but now is always the same as -mvsx.
466mvsx-timode
467Target RejectNegative Undocumented Ignore
468
469mpower8-fusion
470Target Report Mask(P8_FUSION) Var(rs6000_isa_flags)
471Fuse certain integer operations together for better performance on power8.
472
473mpower8-fusion-sign
474Target Undocumented Mask(P8_FUSION_SIGN) Var(rs6000_isa_flags)
475Allow sign extension in fusion operations.
476
477mpower8-vector
478Target Report Mask(P8_VECTOR) Var(rs6000_isa_flags)
479Use vector and scalar instructions added in ISA 2.07.
480
481mcrypto
482Target Report Mask(CRYPTO) Var(rs6000_isa_flags)
483Use ISA 2.07 Category:Vector.AES and Category:Vector.SHA2 instructions.
484
485mdirect-move
486Target Undocumented Mask(DIRECT_MOVE) Var(rs6000_isa_flags) Deprecated
487
488mhtm
489Target Report Mask(HTM) Var(rs6000_isa_flags)
490Use ISA 2.07 transactional memory (HTM) instructions.
491
492mquad-memory
493Target Report Mask(QUAD_MEMORY) Var(rs6000_isa_flags)
494Generate the quad word memory instructions (lq/stq).
495
496mquad-memory-atomic
497Target Report Mask(QUAD_MEMORY_ATOMIC) Var(rs6000_isa_flags)
498Generate the quad word memory atomic instructions (lqarx/stqcx).
499
500mcompat-align-parm
501Target Report Var(rs6000_compat_align_parm) Init(0) Save
502Generate aggregate parameter passing code with at most 64-bit alignment.
503
504moptimize-swaps
505Target Undocumented Var(rs6000_optimize_swaps) Init(1) Save
506Analyze and remove doubleword swaps from VSX computations.
507
508mpower9-misc
509Target Undocumented Report Mask(P9_MISC) Var(rs6000_isa_flags)
510Use certain scalar instructions added in ISA 3.0.
511
512mpower9-vector
513Target Undocumented Report Mask(P9_VECTOR) Var(rs6000_isa_flags)
514Use vector instructions added in ISA 3.0.
515
516mpower9-minmax
517Target Undocumented Mask(P9_MINMAX) Var(rs6000_isa_flags)
518Use the new min/max instructions defined in ISA 3.0.
519
520mtoc-fusion
521Target Undocumented Mask(TOC_FUSION) Var(rs6000_isa_flags)
522Fuse medium/large code model toc references with the memory instruction.
523
524mmodulo
525Target Undocumented Report Mask(MODULO) Var(rs6000_isa_flags)
526Generate the integer modulo instructions.
527
528mfloat128
529Target Report Mask(FLOAT128_KEYWORD) Var(rs6000_isa_flags)
530Enable IEEE 128-bit floating point via the __float128 keyword.
531
532mfloat128-hardware
533Target Report Mask(FLOAT128_HW) Var(rs6000_isa_flags)
534Enable using IEEE 128-bit floating point instructions.
535
536mfloat128-convert
537Target Undocumented Mask(FLOAT128_CVT) Var(rs6000_isa_flags)
538Enable default conversions between __float128 & long double.
539
540mstack-protector-guard=
541Target RejectNegative Joined Enum(stack_protector_guard) Var(rs6000_stack_protector_guard) Init(SSP_TLS)
542Use given stack-protector guard.
543
544Enum
545Name(stack_protector_guard) Type(enum stack_protector_guard)
546Valid arguments to -mstack-protector-guard=:
547
548EnumValue
549Enum(stack_protector_guard) String(tls) Value(SSP_TLS)
550
551EnumValue
552Enum(stack_protector_guard) String(global) Value(SSP_GLOBAL)
553
554mstack-protector-guard-reg=
555Target RejectNegative Joined Var(rs6000_stack_protector_guard_reg_str)
556Use the given base register for addressing the stack-protector guard.
557
558TargetVariable
559int rs6000_stack_protector_guard_reg = 0
560
561mstack-protector-guard-offset=
562Target RejectNegative Joined Integer Var(rs6000_stack_protector_guard_offset_str)
563Use the given offset for addressing the stack-protector guard.
564
565TargetVariable
566long rs6000_stack_protector_guard_offset = 0
567
568;; -mno-speculate-indirect-jumps adds deliberate misprediction to indirect
569;; branches via the CTR.
570mspeculate-indirect-jumps
571Target Undocumented Var(rs6000_speculate_indirect_jumps) Init(1) Save
572