[PATCH,rs6000] Backport of stxvl instruction fix to GCC 7

[Carl Love]

GCC Maintainers:

The following patch is a back port for a commit to mainline prior to
GCC 8 release.  Note, the code fixed by this patch was later modified
in commit 256798 as part of adding vec_xst_len support.  The sldi
instruction gets replaced by an ashift of the operand for the stxvl
instruction.  Commit 256798 adds additional functionality and does not
fix any functional issues.  Hence it is not being back ported, just the
original bug fix given below.

The patch has been tested on 

    powerpc64le-unknown-linux-gnu (Power 8 LE)  

With no regressions.

Please let me know if the patch looks OK for GCC 7.

                         Carl Love
-----------------------------------------------------------------------
2018-07-09  Carl Love  <cel@us.ibm.com>

	Backport from mainline
	2017-09-07  Carl Love  <cel@us.ibm.com>

	* config/rs6000/vsx.md (define_insn "*stxvl"): Add missing argument to
	the sldi instruction.
---
 gcc/config/rs6000/vsx.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gcc/config/rs6000/vsx.md b/gcc/config/rs6000/vsx.md
index eef5357..37d768f 100644
--- a/gcc/config/rs6000/vsx.md
+++ b/gcc/config/rs6000/vsx.md
@@ -3946,7 +3946,7 @@
 	  (match_operand:DI 2 "register_operand" "+r")]
 	 UNSPEC_STXVL))]
   "TARGET_P9_VECTOR && TARGET_64BIT"
-Â Â "sldi %2,%2\;stxvl %x0,%1,%2"
+Â Â "sldi %2,%2,56\;stxvl %x0,%1,%2"
   [(set_attr "length" "8")
    (set_attr "type" "vecstore")])
 
--Â 
2.7.4