[gcc(refs/vendors/redhat/heads/gcc-8-branch)] rs6000: AIX long double builtins for 64 bit long double.

[gcc(refs/vendors/redhat/heads/gcc-8-branch)] rs6000: AIX long double builtins for 64 bit long double.

[Jakub Jelinek]

https://gcc.gnu.org/g:ab9fde198a531ea666c54e7228cc29cb3aed7341

commit ab9fde198a531ea666c54e7228cc29cb3aed7341
Author: David Edelsohn <dje.gcc@gmail.com>
Date:   Tue May 12 17:09:36 2020 -0400

        rs6000: AIX long double builtins for 64 bit long double.
    
        When long doubles are 64 bit, the AIX C library overrides the definitions
        but GCC builtins point to 128 bit names.  This patch overrides the
        builtins for fmodl, frexpl, ldexpl and modfl to refer to the 64 bit symbols.
    
        Backport from mainline
        2020-05-04  Clement Chigot  <clement.chigot@atos.net>
                    David Edelsohn  <dje.gcc@gmail.com>
    
                * config/rs6000/rs6000-call.c (rs6000_init_builtins): Override expli
    cit
                for fmodl, frexpl, ldexpl and modfl builtins.

Diff:
---
 gcc/ChangeLog              |  9 +++++++++
 gcc/config/rs6000/rs6000.c | 26 ++++++++++++++++++++++----
 2 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index dbac95b2889..80f49f246b9 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2020-05-12  David Edelsohn  <dje.gcc@gmail.com>
+
+	Backport from mainline
+	2020-05-04  Clement Chigot  <clement.chigot@atos.net>
+		    David Edelsohn  <dje.gcc@gmail.com>
+
+	* config/rs6000/rs6000.c (rs6000_init_builtins): Override explicit
+	for fmodl, frexpl, ldexpl and modfl builtins.
+
 2020-05-07  Uroš Bizjak  <ubizjak@gmail.com>
 
 	* config/alpha/alpha.c (alpha_atomic_assign_expand_fenv): Use
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index adfe23cfb99..2f7bac6adff 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -17513,10 +17513,28 @@ rs6000_init_builtins (void)
   def_builtin ("__builtin_cpu_is", ftype, RS6000_BUILTIN_CPU_IS);
   def_builtin ("__builtin_cpu_supports", ftype, RS6000_BUILTIN_CPU_SUPPORTS);
 
-  /* AIX libm provides clog as __clog.  */
-  if (TARGET_XCOFF &&
-      (tdecl = builtin_decl_explicit (BUILT_IN_CLOG)) != NULL_TREE)
-    set_user_assembler_name (tdecl, "__clog");
+  if (TARGET_XCOFF)
+    {
+      /* AIX libm provides clog as __clog.  */
+      if ((tdecl = builtin_decl_explicit (BUILT_IN_CLOG)) != NULL_TREE)
+	set_user_assembler_name (tdecl, "__clog");
+
+      /* When long double is 64 bit, some long double builtins of libc
+	 functions (like __builtin_frexpl) must call the double version
+	 (frexp) not the long double version (frexpl) that expects a 128 bit
+	 argument.  */
+      if (! TARGET_LONG_DOUBLE_128)
+	{
+	  if ((tdecl = builtin_decl_explicit (BUILT_IN_FMODL)) != NULL_TREE)
+	    set_user_assembler_name (tdecl, "fmod");
+	  if ((tdecl = builtin_decl_explicit (BUILT_IN_FREXPL)) != NULL_TREE)
+	    set_user_assembler_name (tdecl, "frexp");
+	  if ((tdecl = builtin_decl_explicit (BUILT_IN_LDEXPL)) != NULL_TREE)
+	    set_user_assembler_name (tdecl, "ldexp");
+	  if ((tdecl = builtin_decl_explicit (BUILT_IN_MODFL)) != NULL_TREE)
+	    set_user_assembler_name (tdecl, "modf");
+	}
+    }
 
 #ifdef SUBTARGET_INIT_BUILTINS
   SUBTARGET_INIT_BUILTINS;