rs6000: Correct Power8 cost of l2 cache size [PR97329]

l2 cache size for Power8 is 512kB, it was copied from Power7 before
public.  Tested no performance change for SPEC2017.

gcc/ChangeLog:

2021-03-24  Xionghu Luo  <luoxhu@linux.ibm.com>

	* config/rs6000/rs6000.c (power8_costs): Change l2 cache
	from 256 to 512.

diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 616dae3..34c4eda 100644 (file)
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -1055,7 +1055,7 @@ struct processor_costs power8_cost = {
   COSTS_N_INSNS (17),  /* ddiv */
   128,                 /* cache line size */
   32,                  /* l1 cache */
-  256,                 /* l2 cache */
+  512,                 /* l2 cache */
   12,                  /* prefetch streams */
   COSTS_N_INSNS (3),   /* SF->DF convert */
 };