[PATCH] rs6000: Ignore GFXOPT (and GPOPT) for choosing machine

[Segher Boessenkool]

The function rs6000_machine_from_flags chooses what .machine string to
used based on the rs6000_isa_flags flags.  For that it checks for each
ISA level if something for its ISA_*_MASKS is selected.

This does not work for GFXOPT and GPOPT: these are set as flags in
ISA_2_5_MASKS_SERVER, but they aren't actually new there, they just
are not selected by default for older ISAs (they were optional).

This patch makes OPTION_MASK_PPC_GFXOPT and OPTION_MASK_PPC_GPOPT not
influence the .machine selection.

Tested on all Linux targets; committing.


Segher


2019-07-08  Segher Boessenkool  <seg...@kernel.crashing.org>

        * config/rs6000/rs6000.c (rs6000_machine_from_flags): Ignore
        OPTION_MASK_PPC_GFXOPT and OPTION_MASK_PPC_GPOPT for selecting the
        .machine string.

---
 gcc/config/rs6000/rs6000.c | 22 +++++++++++++---------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index f59f3a9..bec3436 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -5547,22 +5547,26 @@ const char *rs6000_machine;
 const char *
 rs6000_machine_from_flags (void)
 {
-  if ((rs6000_isa_flags & (ISA_FUTURE_MASKS_SERVER & ~ISA_3_0_MASKS_SERVER))
-      != 0)
+  HOST_WIDE_INT flags = rs6000_isa_flags;
+
+  /* Disable the flags that should never influence the .machine selection.  */
+  flags &= ~(OPTION_MASK_PPC_GFXOPT | OPTION_MASK_PPC_GPOPT);
+
+  if ((flags & (ISA_FUTURE_MASKS_SERVER & ~ISA_3_0_MASKS_SERVER)) != 0)
     return "future";
-  if ((rs6000_isa_flags & (ISA_3_0_MASKS_SERVER & ~ISA_2_7_MASKS_SERVER)) != 0)
+  if ((flags & (ISA_3_0_MASKS_SERVER & ~ISA_2_7_MASKS_SERVER)) != 0)
     return "power9";
-  if ((rs6000_isa_flags & (ISA_2_7_MASKS_SERVER & ~ISA_2_6_MASKS_SERVER)) != 0)
+  if ((flags & (ISA_2_7_MASKS_SERVER & ~ISA_2_6_MASKS_SERVER)) != 0)
     return "power8";
-  if ((rs6000_isa_flags & (ISA_2_6_MASKS_SERVER & ~ISA_2_5_MASKS_SERVER)) != 0)
+  if ((flags & (ISA_2_6_MASKS_SERVER & ~ISA_2_5_MASKS_SERVER)) != 0)
     return "power7";
-  if ((rs6000_isa_flags & (ISA_2_5_MASKS_SERVER & ~ISA_2_4_MASKS)) != 0)
+  if ((flags & (ISA_2_5_MASKS_SERVER & ~ISA_2_4_MASKS)) != 0)
     return "power6";
-  if ((rs6000_isa_flags & (ISA_2_4_MASKS & ~ISA_2_1_MASKS)) != 0)
+  if ((flags & (ISA_2_4_MASKS & ~ISA_2_1_MASKS)) != 0)
     return "power5";
-  if ((rs6000_isa_flags & ISA_2_1_MASKS) != 0)
+  if ((flags & ISA_2_1_MASKS) != 0)
     return "power4";
-  if ((rs6000_isa_flags & OPTION_MASK_POWERPC64) != 0)
+  if ((flags & OPTION_MASK_POWERPC64) != 0)
     return "ppc64";
   return "ppc";
 }
-- 
1.8.3.1