[gcc(refs/vendors/redhat/heads/gcc-8-branch)] rs6000 Add command line and builtin compatibility check

[Jakub Jelinek]

https://gcc.gnu.org/g:e94468b65dbf930691fd1765894c34c0f0020249

commit e94468b65dbf930691fd1765894c34c0f0020249
Author: Carl Love <carll@us.ibm.com>
Date:   Tue Mar 31 11:53:47 2020 -0500

    rs6000 Add command line and builtin compatibility check
    
    2020-03-31  Carl Love  <cel@us.ibm.com>
    
            backport of mainline commit
    
            commit 68dd57808f7c0147acdb5ca72c88ff655afcb0ce
            Author: Carl Love <carll@us.ibm.com>
            Date:   Fri Mar 20 18:15:05 2020 -0500
    
            whith change log typo fixed.
    
            PR target/87583
            * gcc/config/rs6000/rs6000.c (rs6000_option_override_internal):
            Add check for TARGET_FPRND for Power 7 or newer.

Diff:
---
 gcc/ChangeLog              | 14 ++++++++++++++
 gcc/config/rs6000/rs6000.c |  8 ++++++++
 2 files changed, 22 insertions(+)

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 5d0e90eb961..c31160b42f4 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,17 @@
+2020-03-31  Carl Love  <cel@us.ibm.com>
+
+	backport of mainline commit
+
+	commit 68dd57808f7c0147acdb5ca72c88ff655afcb0ce
+	Author: Carl Love <carll@us.ibm.com>
+	Date:   Fri Mar 20 18:15:05 2020 -0500
+
+	whith change log typo fixed.
+
+	PR target/87583
+	* gcc/config/rs6000/rs6000.c (rs6000_option_override_internal):
+	Add check for TARGET_FPRND for Power 7 or newer.
+
 2020-03-29  Martin Liska  <mliska@suse.cz>
 
 	Backport from mainline
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 25d71c82daa..5c7b4322386 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -4401,6 +4401,14 @@ rs6000_option_override_internal (bool global_init_p)
       rs6000_isa_flags &= ~OPTION_MASK_CRYPTO;
     }
 
+  if (!TARGET_FPRND && TARGET_VSX)
+    {
+      if (rs6000_isa_flags_explicit & OPTION_MASK_FPRND)
+	/* TARGET_VSX = 1 implies Power 7 and newer */
+	error ("%qs requires %qs", "-mvsx", "-mfprnd");
+      rs6000_isa_flags &= ~OPTION_MASK_FPRND;
+    }
+
   if (TARGET_DIRECT_MOVE && !TARGET_VSX)
     {
       if (rs6000_isa_flags_explicit & OPTION_MASK_DIRECT_MOVE)