ping
Setting HONOR_REG_ALLOC_ORDER improves codesize with -Os, however it generates
slower and larger code with -O2 and higher. So only set it when optimizing for
size. On Cortex-A57 this improves SPECINT2006 by 0.15% and SPECFP2006 by 0.25%
while reducing codesize.
Bootstrap OK, OK for commit?
ChangeLog:
2019-09-09 Wilco Dijkstra <wdijk...@arm.com>
* config/arm/arm.h (HONOR_REG_ALLOC_ORDER): Set when optimizing for
size.
--
diff --git a/gcc/config/arm/arm.h b/gcc/config/arm/arm.h
index
8d023389eec469ad9c8a4e88edebdad5f3c23769..e3473e29fbbb964ff1136c226fbe30d35dbf7b39
100644
--- a/gcc/config/arm/arm.h
+++ b/gcc/config/arm/arm.h
@@ -1065,9 +1065,8 @@ extern int arm_regs_in_sequence[];
/* Use different register alloc ordering for Thumb. */
#define ADJUST_REG_ALLOC_ORDER arm_order_regs_for_local_alloc ()
-/* Tell IRA to use the order we define rather than messing it up with its
- own cost calculations. */
-#define HONOR_REG_ALLOC_ORDER 1
+/* Tell IRA to use the order we define when optimizing for size. */
+#define HONOR_REG_ALLOC_ORDER optimize_size
/* Interrupt functions can only use registers that have already been
saved by the prologue, even if they would normally be
