This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
[patch] h8300.md: Add a new peephole2.
- From: Kazu Hirata <kazu at cs dot umass dot edu>
- To: gcc-patches at gcc dot gnu dot org
- Date: Mon, 31 Mar 2003 14:08:00 -0500 (EST)
- Subject: [patch] h8300.md: Add a new peephole2.
Hi,
Attached is a patch to add a new peephole2.
The new peephole2 transforms
cmp.l #1,er0
bhi .L1
into
shlr.l er0
bne .L1
saving 4 bytes. Similar transformation is done for "cmp.l #2,er0" on
H8S because H8S has 2-bit shift instructions. Also, the reversed
branch condition is handled.
Tested on h8300 port. Committed.
Kazu Hirata
2003-03-31 Kazu Hirata <kazu at cs dot umass dot edu>
* config/h8300/h8300.md (a peephole2): New.
Index: h8300.md
===================================================================
RCS file: /cvs/gcc/gcc/gcc/config/h8300/h8300.md,v
retrieving revision 1.208
diff -u -r1.208 h8300.md
--- h8300.md 31 Mar 2003 14:44:12 -0000 1.208
+++ h8300.md 31 Mar 2003 15:30:50 -0000
@@ -4101,8 +4101,10 @@
;; dead 0xffffff?? except -1 and -2 eq/ne xor.b and not.l
;; dead 0xffff??ff eq/ne xor.b and not.l
;;
-;; dead 1 geu/ltu and.b and test
-;; dead 3 geu/ltu and.b and test
+;; dead 1 geu/ltu shlr.l
+;; dead 3 (H8S) geu/ltu shlr.l
+;;
+;; dead 3 (H8/300H) geu/ltu and.b and test
;; dead 7 geu/ltu and.b and test
;; dead 15 geu/ltu and.b and test
;; dead 31 geu/ltu and.b and test
@@ -4222,6 +4224,44 @@
(label_ref (match_dup 2))
(pc)))]
"operands[4] = GEN_INT (INTVAL (operands[1]) ^ -1);")
+
+;; Transform
+;;
+;; cmp.l #1,er0
+;; bhi .L1
+;;
+;; into
+;;
+;; shlr.l er0
+;; bne .L1
+
+(define_peephole2
+ [(set (cc0)
+ (compare (match_operand:SI 0 "register_operand" "")
+ (match_operand:SI 1 "const_int_operand" "")))
+ (set (pc)
+ (if_then_else (match_operator 2 "gtuleu_operator"
+ [(cc0) (const_int 0)])
+ (label_ref (match_operand 3 "" ""))
+ (pc)))]
+ "(TARGET_H8300H || TARGET_H8300S)
+ && peep2_reg_dead_p (1, operands[0])
+ && (INTVAL (operands[1]) == 1
+ || (TARGET_H8300S && INTVAL (operands[1]) == 3))"
+ [(parallel [(set (match_dup 0)
+ (lshiftrt:SI (match_dup 0)
+ (match_dup 5)))
+ (clobber (scratch:QI))])
+ (set (cc0)
+ (match_dup 0))
+ (set (pc)
+ (if_then_else (match_dup 4)
+ (label_ref (match_dup 3))
+ (pc)))]
+ "operands[4] = ((GET_CODE (operands[2]) == GTU) ?
+ gen_rtx_NE (VOIDmode, cc0_rtx, const0_rtx) :
+ gen_rtx_EQ (VOIDmode, cc0_rtx, const0_rtx));
+ operands[5] = GEN_INT (exact_log2 (INTVAL (operands[1]) + 1));")
;; Transform A <= 1 to (A & 0xfffffffe) == 0.