[gcc(refs/users/meissner/heads/work027)] PowerPC: Set long double size for IBM/IEEE.

[Michael Meissner]

https://gcc.gnu.org/g:47fad0773269fb7b50b526f5b0d20329c32d1e12

commit 47fad0773269fb7b50b526f5b0d20329c32d1e12
Author: Michael Meissner <meissner@linux.ibm.com>
Date:   Thu Nov 12 09:32:47 2020 -0500

    PowerPC: Set long double size for IBM/IEEE.
    
    gcc/
    2020-11-12  Michael Meissner  <meissner@linux.ibm.com>
    
            * config/rs6000/rs6000.c (rs6000_option_override_internal): If the
            user explicitly used -mabi=ieeelongdouble or -mabi=ibmlongdouble,
            set the long double size to 128.
            * doc/invoke.texi (PowerPC options): Document that an explicit
            -mabi=ieeelongdouble or -mabi=ibmlongdouble implicitly sets
            -mlong-double-128.

Diff:
---
 gcc/config/rs6000/rs6000.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 35e9c844e17..6edd17a0b69 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -4131,8 +4131,13 @@ rs6000_option_override_internal (bool global_init_p)
 
   /* Use long double size to select the appropriate long double.  We use
      TYPE_PRECISION to differentiate the 3 different long double types.  We map
-     128 into the precision used for TFmode.  */
-  int default_long_double_size = (RS6000_DEFAULT_LONG_DOUBLE_SIZE == 64
+     128 into the precision used for TFmode.
+
+     If the user explicitly used -mabi=ieeelongdouble or -mabi=ibmlongdouble,
+     but the compiler was configured for default 64-bit long doubles, set the
+     long double to be 128.  */
+  int default_long_double_size = ((RS6000_DEFAULT_LONG_DOUBLE_SIZE == 64
+				   && !global_options_set.x_rs6000_ieeequad)
 				  ? 64
 				  : FLOAT_PRECISION_TFmode);