[gcc(refs/users/wschmidt/heads/pr87560)] rs6000: Fix -mpower9-vector -mno-altivec ICE (PR87560)

[William Schmidt]

https://gcc.gnu.org/g:93c6ffaa6225bbf6279919ec512349e6374a248a

commit 93c6ffaa6225bbf6279919ec512349e6374a248a
Author: Bill Schmidt <wschmidt@linux.ibm.com>
Date:   Mon Mar 2 14:24:12 2020 -0600

    rs6000: Fix -mpower9-vector -mno-altivec ICE (PR87560)
    
    PR87560	reports	an ICE when a test case	is compiled with -mpower9-vector
    and -mno-altivec.  This	patch terminates compilation with an error when
    this combination (and other unreasonable ones) are requested.
    
    Bootstrapped and tested on powerpc64le-unknown-linux-gnu with no
    regressions.  Reported error is now:
    
    f951: Error: '-mno-altivec' turns off '-mpower9-vector'
    
    2020-03-02  Bill Schmidt  <wschmidt@linux.ibm.com>
    
            * rs6000-cpus.def (OTHER_ALTIVEC_MASKS): New #define.
            * rs6000.c (rs6000_disable_incompatible_switches): Add table entry
    	for OPTION_MASK_ALTIVEC.

Diff:
---
 gcc/config/rs6000/rs6000-cpus.def | 4 ++++
 gcc/config/rs6000/rs6000.c        | 1 +
 2 files changed, 5 insertions(+)

diff --git a/gcc/config/rs6000/rs6000-cpus.def b/gcc/config/rs6000/rs6000-cpus.def
index 193d77e..ff1db60 100644
--- a/gcc/config/rs6000/rs6000-cpus.def
+++ b/gcc/config/rs6000/rs6000-cpus.def
@@ -101,6 +101,10 @@
 				 | OPTION_MASK_FLOAT128_KEYWORD		\
 				 | OPTION_MASK_P8_VECTOR)
 
+/* Flags that need to be turned off if -mno-altivec.  */
+#define OTHER_ALTIVEC_MASKS	(OTHER_VSX_VECTOR_MASKS			\
+				 | OPTION_MASK_VSX)
+
 #define POWERPC_7400_MASK	(OPTION_MASK_PPC_GFXOPT | OPTION_MASK_ALTIVEC)
 
 /* Deal with ports that do not have -mstrict-align.  */
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 9910b27..ecbf7ae 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -23632,6 +23632,7 @@ rs6000_disable_incompatible_switches (void)
     { OPTION_MASK_P9_VECTOR,	OTHER_P9_VECTOR_MASKS,	"power9-vector"	},
     { OPTION_MASK_P8_VECTOR,	OTHER_P8_VECTOR_MASKS,	"power8-vector"	},
     { OPTION_MASK_VSX,		OTHER_VSX_VECTOR_MASKS,	"vsx"		},
+    { OPTION_MASK_ALTIVEC,	OTHER_ALTIVEC_MASKS,	"altivec"	},
   };
 
   for (i = 0; i < ARRAY_SIZE (flags); i++)