[gcc(refs/users/ppalka/heads/libstdcxx-constrained-algos)] aarch64: Fix BE SVE mode punning involving floats

[Patrick Palka]

https://gcc.gnu.org/g:5c06093ce90ac3fc1efe89c1897ea19b805cdd3d

commit 5c06093ce90ac3fc1efe89c1897ea19b805cdd3d
Author: Richard Sandiford <richard.sandiford@arm.com>
Date:   Wed Jan 15 16:52:04 2020 +0000

    aarch64: Fix BE SVE mode punning involving floats
    
    The patterns used by aarch64_split_sve_subreg_move only support
    integer modes, so if the widest mode is a float, we should get
    its integer equivalent.
    
    Fixes gcc.target/aarch64/sel_3.c for big-endian targets.
    
    2020-01-16  Richard Sandiford  <richard.sandiford@arm.com>
    
    gcc/
    	* config/aarch64/aarch64.c (aarch64_split_sve_subreg_move): Apply
    	aarch64_sve_int_mode to each mode.

Diff:
---
 gcc/ChangeLog                | 5 +++++
 gcc/config/aarch64/aarch64.c | 4 ++--
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 4a1c1ee..0642993 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2020-01-16  Richard Sandiford  <richard.sandiford@arm.com>
+
+	* config/aarch64/aarch64.c (aarch64_split_sve_subreg_move): Apply
+	aarch64_sve_int_mode to each mode.
+
 2020-01-15  David Malcolm  <dmalcolm@redhat.com>
 
 	* doc/analyzer.texi (Overview): Add note about
diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index ac89cc1..600a238 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -4827,8 +4827,8 @@ aarch64_split_sve_subreg_move (rtx dest, rtx ptrue, rtx src)
   /* Decide which REV operation we need.  The mode with wider elements
      determines the mode of the operands and the mode with the narrower
      elements determines the reverse width.  */
-  machine_mode mode_with_wider_elts = GET_MODE (dest);
-  machine_mode mode_with_narrower_elts = GET_MODE (src);
+  machine_mode mode_with_wider_elts = aarch64_sve_int_mode (GET_MODE (dest));
+  machine_mode mode_with_narrower_elts = aarch64_sve_int_mode (GET_MODE (src));
   if (GET_MODE_UNIT_SIZE (mode_with_wider_elts)
       < GET_MODE_UNIT_SIZE (mode_with_narrower_elts))
     std::swap (mode_with_wider_elts, mode_with_narrower_elts);