https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79569
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2017-02-17
CC| |jakub at gcc dot gnu.org,
| |uros at gcc dot gnu.org
Ever confirmed|0 |1
--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
I bet this goes all the way down to r125180 or so, ix86_handle_option returns
false for OPT_3dnowa. So, either the option should not be recognized, then we
should add Ignore to it etc., or we should make it work (again?). Right now it
seems the effect of -m3dnowa happens only if -march= for a CPU that includes
3dnowa is included.
To make -m3dnowa work, perhaps something like following would DTRT (plus
testcases):
--- gcc/common/config/i386/i386-common.c.jj 2017-01-12 22:29:00.000000000
+0100
+++ gcc/common/config/i386/i386-common.c 2017-02-17 10:55:20.023152107
+0100
@@ -35,6 +35,8 @@ along with GCC; see the file COPYING3.
#define OPTION_MASK_ISA_MMX_SET OPTION_MASK_ISA_MMX
#define OPTION_MASK_ISA_3DNOW_SET \
(OPTION_MASK_ISA_3DNOW | OPTION_MASK_ISA_MMX_SET)
+#define OPTION_MASK_ISA_3DNOW_A_SET \
+ (OPTION_MASK_ISA_3DNOW_A | OPTION_MASK_ISA_3DNOW_SET)
#define OPTION_MASK_ISA_SSE_SET OPTION_MASK_ISA_SSE
#define OPTION_MASK_ISA_SSE2_SET \
@@ -291,7 +293,17 @@ ix86_handle_option (struct gcc_options *
return true;
case OPT_m3dnowa:
- return false;
+ if (value)
+ {
+ opts->x_ix86_isa_flags |= OPTION_MASK_ISA_3DNOW_A_SET;
+ opts->x_ix86_isa_flags_explicit |= OPTION_MASK_ISA_3DNOW_A_SET;
+ }
+ else
+ {
+ opts->x_ix86_isa_flags &= ~OPTION_MASK_ISA_3DNOW_A_UNSET;
+ opts->x_ix86_isa_flags_explicit |= OPTION_MASK_ISA_3DNOW_A_UNSET;
+ }
+ return true;
case OPT_msse:
if (value)
