Here's the follow-up, getting rid of the observed
alignment-padding in execute/930126-1.c: the x parameter in f
spuriously being runtime-aligned to BITS_PER_WORD. I separated
this change because this is an older issue, a change introduced
in r94104 where BITS_PER_WORD was chosen perhaps because we
expect register-sized writes into this area. Here, we instead
align to a minimum of PREFERRED_STACK_BOUNDARY, but of course
gated on ! STRICT_ALIGNMENT.
Regtested cris-elf and x86_64-pc-linux-gnu.
Ok to commit?
gcc:
* function.c (assign_parm_setup_block): If not STRICT_ALIGNMENT,
instead of always BITS_PER_WORD, align the stacked
parameter to a minimum PREFERRED_STACK_BOUNDARY.
--- function.c.orig2 Sat Feb 9 00:53:17 2019
+++ function.c Sat Feb 9 23:21:35 2019
@@ -2912,7 +2912,10 @@ assign_parm_setup_block (struct assign_p
size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
if (stack_parm == 0)
{
- SET_DECL_ALIGN (parm, MAX (DECL_ALIGN (parm), BITS_PER_WORD));
+ HOST_WIDE_INT min_parm_align
+ = STRICT_ALIGNMENT ? BITS_PER_WORD : PREFERRED_STACK_BOUNDARY;
+
+ SET_DECL_ALIGN (parm, MAX (DECL_ALIGN (parm), min_parm_align));
if (DECL_ALIGN (parm) > MAX_SUPPORTED_STACK_ALIGNMENT)
{
rtx allocsize = gen_int_mode (size_stored, Pmode);
brgds, H-P
