Fixup unaligned load/store cost for znver4

Currently unaligned YMM and ZMM load and store costs are cheaper than
aligned which causes the vectorizer to purposely mis-align accesses
by adding an alignment prologue.  It looks like the unaligned costs
were simply left untouched from znver3 where they equate the aligned
costs when tweaking aligned costs for znver4.  The following makes
the unaligned costs equal to the aligned costs.

This avoids the miscompile seen in PR115843 but it's of course not
a real fix for the issue uncovered there.  But it makes it qualify
as a regression fix.

	PR tree-optimization/115843
	* config/i386/x86-tune-costs.h (znver4_cost): Update unaligned
	load and store cost from the aligned costs.

diff --git a/gcc/config/i386/x86-tune-costs.h b/gcc/config/i386/x86-tune-costs.h
index a933794ed505902a27d63eade2d8051bf2ec4b2f..2ac75c35aee60c12853433e94fee4ecfd7309b4c 100644 (file)
--- a/gcc/config/i386/x86-tune-costs.h
+++ b/gcc/config/i386/x86-tune-costs.h
@@ -1924,8 +1924,8 @@ struct processor_costs znver4_cost = {
                                           in 32bit, 64bit, 128bit, 256bit and 512bit */
   {8, 8, 8, 12, 12},                   /* cost of storing SSE register
                                           in 32bit, 64bit, 128bit, 256bit and 512bit */
-  {6, 6, 6, 6, 6},                     /* cost of unaligned loads.  */
-  {8, 8, 8, 8, 8},                     /* cost of unaligned stores.  */
+  {6, 6, 10, 10, 12},                  /* cost of unaligned loads.  */
+  {8, 8, 8, 12, 12},                   /* cost of unaligned stores.  */
   2, 2, 2,                             /* cost of moving XMM,YMM,ZMM
                                           register.  */
   6,                                   /* cost of moving SSE register to integer.  */