mirror/gcc
2
0
Fork 0
mirror of git://gcc.gnu.org/git/gcc.git synced 2025-03-21 22:51:06 +08:00
Code Issues Packages Projects Releases Wiki Activity

cris.md: Post-reload, split/generate clobberless zero source moves

Browse Source 
A separated follow-up to the previous change: Also emit moves
from zero as not clobbering condition-codes.

(note: actually folded into the previous ChangeLog-entry)
gcc:
	* 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.
This commit is contained in:
Hans-Peter Nilsson 2020-01-28 00:59:41 +01:00
parent e49cee5c8d
commit 12bdaa7d3e
2 changed files with 21 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
gcc/ChangeLog
View File

@ -43,11 +43,14 @@
* config/cris/cris.h (REVERSIBLE_CC_MODE): Define to true.
* config/cris/cris.md ("movsi"): For memory destination
post-reload, generate clobberless variant.
post-reload, generate clobberless variant. Similarly for a
zero-source post-reload.
("*mov_tomem<mode>_split"): New split.
("*mov_tomem<mode>"): New insn.
("enabled", mov_tomem_enabled): Define and use to exclude "x" ->
"Q>m" for less-than-SImode.
("*mov_fromzero<mode>_split"): New split.
("*mov_fromzero<mode>"): New insn.
2020-05-08 Vladimir Makarov <vmakarov@redhat.com>

19
gcc/config/cris/cris.md
View File

@ -449,8 +449,9 @@
/* 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 @@
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