@@ -449,8 +449,9 @@ (define_expand "movsi"
/* At post-reload time, we'll get here for e.g. split multi-mode insns
with a memory destination. Go directly to the clobber-less variant.
- FIXME: Also applies to zero source. */
- if (MEM_P (operands[0]) && reload_completed)
+ FIXME: Also applies to special-register source or destination. */
+ if (reload_completed
+ && (MEM_P (operands[0]) || operands[1] == const0_rtx))
{
emit_insn (gen_rtx_SET (operands[0], operands[1]));
DONE;
@@ -697,6 +698,20 @@ (define_insn "*mov_tomem<mode>"
move %1,%0"
[(set_attr "slottable" "yes,yes,yes,no,no,no")
(set_attr "enabled" "<mov_tomem_enabled>")])
+
+(define_split ;; "*mov_fromzero<mode>_split"
+ [(set (match_operand:BWD 0 "register_operand") (const_int 0))
+ (clobber (reg:CC CRIS_CC0_REGNUM))]
+ "reload_completed
+ && REGNO(operands[0]) <= CRIS_LAST_GENERAL_REGISTER"
+ [(set (match_dup 0) (const_int 0))]
+ "")
+
+(define_insn "*mov_fromzero<mode>"
+ [(set (match_operand:BWD 0 "register_operand" "=r") (const_int 0))]
+ "reload_completed"
+ "clear<m> %0"
+ [(set_attr "slottable" "yes")])
;; Movem patterns. Primarily for use in function prologue and epilogue.
;; Unfortunately, movem stores R0 in the highest memory location, thus
* config/cris/cris.md ("movsi"): For a zero-source post-reload, generate a clobberless variant. ("*mov_fromzero<mode>_split"): New split. ("*mov_fromzero<mode>"): New insn. A separated follow-up to the previous change: Also emit moves from zero as not clobbering condition-codes. --- gcc/config/cris/cris.md | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-)