Hi,
This patch is similar to what I did for ThunderX where I increase
the costs of these instructions slightly to point out there is a
slight cost to using them over using the two instructions.
OK? Bootstrapped and tested on aarch64-linux-gnu with no regressions.
This gave ~2% on SPEC CPU 2006 int.
Thanks,
Andrew Pinski
ChangeLog:
* config/aarch64/aarch64-cost-tables.h (thunderx2t99_extra_costs):
Increment Arith_shift, Arith_shift_reg, Log_shift, Log_shift_reg and
Extend_arith by 1.
Index: gcc/config/aarch64/aarch64-cost-tables.h
===================================================================
--- gcc/config/aarch64/aarch64-cost-tables.h (revision 249583)
+++ gcc/config/aarch64/aarch64-cost-tables.h (working copy)
@@ -239,12 +239,12 @@
0, /* Logical. */
0, /* Shift. */
0, /* Shift_reg. */
- COSTS_N_INSNS (1), /* Arith_shift. */
- COSTS_N_INSNS (1), /* Arith_shift_reg. */
- COSTS_N_INSNS (1), /* Log_shift. */
- COSTS_N_INSNS (1), /* Log_shift_reg. */
+ COSTS_N_INSNS (1)+1, /* Arith_shift. */
+ COSTS_N_INSNS (1)+1, /* Arith_shift_reg. */
+ COSTS_N_INSNS (1)+1, /* Log_shift. */
+ COSTS_N_INSNS (1)+1, /* Log_shift_reg. */
0, /* Extend. */
- COSTS_N_INSNS (1), /* Extend_arith. */
+ COSTS_N_INSNS (1)+1, /* Extend_arith. */
0, /* Bfi. */
0, /* Bfx. */
COSTS_N_INSNS (3), /* Clz. */
