The new opt_mode asserts triggered for replace_reg_with_saved_mem
because it was passing bytes rather than bits to mode_for_size.
Previously we ended up with a BLKmode register instead, but
presumably that didn't matter because this is "only" used for
debug insns.
Tested on bfin-elf (as far as possible); this code isn't used
for LRA targets. Applied as obvious.
Richard
2018-01-11 Richard Sandiford <richard.sandif...@linaro.org>
gcc/
PR rtl-optimization/83761
* caller-save.c (replace_reg_with_saved_mem): Pass bits rather
than bytes to mode_for_size.
Index: gcc/caller-save.c
===================================================================
--- gcc/caller-save.c 2018-01-03 21:42:44.552647435 +0000
+++ gcc/caller-save.c 2018-01-11 09:49:29.873718858 +0000
@@ -1147,7 +1147,8 @@ replace_reg_with_saved_mem (rtx *loc,
machine_mode smode = save_mode[regno];
gcc_assert (smode != VOIDmode);
if (hard_regno_nregs (regno, smode) > 1)
- smode = mode_for_size (exact_div (GET_MODE_SIZE (mode), nregs),
+ smode = mode_for_size (exact_div (GET_MODE_BITSIZE (mode),
+ nregs),
GET_MODE_CLASS (mode), 0).require ();
XVECEXP (mem, 0, i) = gen_rtx_REG (smode, regno + i);
}
