This patch fixes the shift costs for Cortex-A53 so they are more accurate -
immediate shifts use
SBFM/UBFM which takes 2 cycles, register controlled shifts take 1 cycle.
Bootstrap and regression
OK.
ChangeLog:
2015-03-05 Wilco Dijkstra <wdijk...@arm.com>
* gcc/config/arm/aarch-cost-tables.h (cortexa53_extra_costs):
Make Cortex-A53 shift costs more accurate.
---
gcc/config/arm/aarch-cost-tables.h | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/gcc/config/arm/aarch-cost-tables.h
b/gcc/config/arm/aarch-cost-tables.h
index 05e96a9..6bb8ede 100644
--- a/gcc/config/arm/aarch-cost-tables.h
+++ b/gcc/config/arm/aarch-cost-tables.h
@@ -130,12 +130,12 @@ const struct cpu_cost_table cortexa53_extra_costs =
0, /* arith. */
0, /* logical. */
COSTS_N_INSNS (1), /* shift. */
- COSTS_N_INSNS (2), /* shift_reg. */
+ 0, /* shift_reg. */
COSTS_N_INSNS (1), /* arith_shift. */
- COSTS_N_INSNS (2), /* arith_shift_reg. */
+ COSTS_N_INSNS (1), /* arith_shift_reg. */
COSTS_N_INSNS (1), /* log_shift. */
- COSTS_N_INSNS (2), /* log_shift_reg. */
- 0, /* extend. */
+ COSTS_N_INSNS (1), /* log_shift_reg. */
+ COSTS_N_INSNS (1), /* extend. */
COSTS_N_INSNS (1), /* extend_arith. */
COSTS_N_INSNS (1), /* bfi. */
COSTS_N_INSNS (1), /* bfx. */
--
1.9.1
