xref: /netbsd-src/external/gpl3/gcc.old/dist/gcc/config/m32c/cond.md (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1;; Machine Descriptions for R8C/M16C/M32C
2;; Copyright (C) 2005, 2007, 2008
3;; Free Software Foundation, Inc.
4;; Contributed by Red Hat.
5;;
6;; This file is part of GCC.
7;;
8;; GCC is free software; you can redistribute it and/or modify it
9;; under the terms of the GNU General Public License as published
10;; by the Free Software Foundation; either version 3, or (at your
11;; option) any later version.
12;;
13;; GCC is distributed in the hope that it will be useful, but WITHOUT
14;; ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15;; or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
16;; License for more details.
17;;
18;; You should have received a copy of the GNU General Public License
19;; along with GCC; see the file COPYING3.  If not see
20;; <http://www.gnu.org/licenses/>.
21
22; conditionals - cmp, jcc, setcc, etc.
23
24; Special note about conditional instructions: GCC always emits the
25; compare right before the insn, which is good, because m32c's mov
26; insns modify the flags.  However, this means that any conditional
27; insn that may require reloading must be kept with its compare until
28; after reload finishes, else the reload insns might clobber the
29; flags.  Thus, these rules:
30;
31; * the cmp* expanders just save the operands in compare_op0 and
32;   compare_op1 via m32c_pend_compare.
33; * conditional insns that won't need reload can call
34;   m32c_unpend_compare before their expansion.
35; * other insns must expand to include the compare operands within,
36;   then split after reload to a separate compare and conditional.
37
38; Until support for relaxing is supported in gas, we must assume that
39; short labels won't reach, so we must use long labels.
40; Unfortunately, there aren't any conditional jumps with long labels,
41; so instead we invert the conditional and jump around a regular jump.
42
43; Note that we can, at some point in the future, add code to omit the
44; "cmp" portion of the insn if the preceding insn happened to set the
45; right flags already.  For example, a mov followed by a "cmp *,0" is
46; redundant; the move already set the Z flag.
47
48(define_insn_and_split "cbranch<mode>4"
49  [(set (pc) (if_then_else
50	      (match_operator 0 "m32c_cmp_operator"
51			      [(match_operand:QHPSI 1 "mra_operand" "RraSd")
52			       (match_operand:QHPSI 2 "mrai_operand" "iRraSd")])
53              (label_ref (match_operand 3 "" ""))
54	      (pc)))]
55  ""
56  "#"
57  "reload_completed"
58  [(set (reg:CC FLG_REGNO)
59	(compare (match_dup 1)
60		 (match_dup 2)))
61   (set (pc) (if_then_else (match_op_dup 0 [(reg:CC FLG_REGNO) (const_int 0)])
62			   (label_ref (match_dup 3))
63			   (pc)))]
64  ""
65  )
66
67(define_insn "bcc_op"
68  [(set (pc)
69        (if_then_else (match_operator 0 "ordered_comparison_operator"
70		       [(reg:CC FLG_REGNO) (const_int 0)])
71                      (label_ref (match_operand 1 ""))
72                      (pc)))]
73  ""
74  "j%c0\t%l1"
75  [(set_attr "flags" "n")]
76)
77
78(define_insn "stzx_16"
79  [(set (match_operand:QI 0 "mrai_operand" "=R0w,R0w,R0w")
80	(if_then_else:QI (eq (reg:CC FLG_REGNO) (const_int 0))
81			 (match_operand:QI 1 "const_int_operand" "i,i,0")
82			 (match_operand:QI 2 "const_int_operand" "i,0,i")))]
83  "TARGET_A16 && reload_completed"
84  "@
85   stzx\t%1,%2,%0
86   stz\t%1,%0
87   stnz\t%2,%0"
88  [(set_attr "flags" "n,n,n")]
89)
90
91(define_insn "stzx_24_<mode>"
92  [(set (match_operand:QHI 0 "mrai_operand" "=RraSd,RraSd,RraSd")
93	(if_then_else:QHI (eq (reg:CC FLG_REGNO) (const_int 0))
94			 (match_operand:QHI 1 "const_int_operand" "i,i,0")
95			 (match_operand:QHI 2 "const_int_operand" "i,0,i")))]
96  "TARGET_A24 && reload_completed"
97  "@
98   stzx.<bwl>\t%1,%2,%0
99   stz.<bwl>\t%1,%0
100   stnz.<bwl>\t%2,%0"
101  [(set_attr "flags" "n,n,n")])
102
103(define_insn_and_split "stzx_reversed_<mode>"
104  [(set (match_operand:QHI 0 "m32c_r0_operand" "=R0w")
105	(if_then_else:QHI (ne (reg:CC FLG_REGNO) (const_int 0))
106			 (match_operand:QHI 1 "const_int_operand" "")
107			 (match_operand:QHI 2 "const_int_operand" "")))]
108  "(TARGET_A24 || GET_MODE (operands[0]) == QImode) && reload_completed"
109  "#"
110  ""
111  [(set (match_dup 0)
112	(if_then_else:QHI (eq (reg:CC FLG_REGNO) (const_int 0))
113		      (match_dup 2)
114		      (match_dup 1)))]
115  ""
116  )
117
118
119(define_insn "cmp<mode>_op"
120  [(set (reg:CC FLG_REGNO)
121	(compare (match_operand:QHPSI 0 "mra_operand" "RraSd")
122		 (match_operand:QHPSI 1 "mrai_operand" "RraSdi")))]
123  ""
124  "* return m32c_output_compare(insn, operands); "
125  [(set_attr "flags" "oszc")])
126
127;; m32c_conditional_register_usage changes the setcc_gen_code array to
128;; point to the _24 variants if needed.
129
130;; We need to keep the compare and conditional sets together through
131;; reload, because reload might need to add address reloads to the
132;; set, which would clobber the flags.  By keeping them together, the
133;; reloads get put before the compare, thus preserving the flags.
134
135;; These are the post-split patterns for the conditional sets.
136
137(define_insn "scc_op"
138  [(set (match_operand:QI 0 "register_operand" "=Rqi")
139	(match_operator:QI 1 "ordered_comparison_operator"
140	 [(reg:CC FLG_REGNO) (const_int 0)]))]
141  "TARGET_A16 && reload_completed"
142  "* return m32c_scc_pattern(operands, GET_CODE (operands[1]));")
143
144(define_insn "scc_24_op"
145  [(set (match_operand:HI 0 "mra_operand" "=RhiSd")
146	(match_operator:HI 1 "ordered_comparison_operator"
147	 [(reg:CC FLG_REGNO) (const_int 0)]))]
148  "TARGET_A24 && reload_completed"
149  "sc%c1\t%0"
150  [(set_attr "flags" "n")]
151)
152
153;; These are the pre-split patterns for the conditional sets.
154
155(define_insn_and_split "cstore<mode>4"
156  [(set (match_operand:QI 0 "register_operand" "=Rqi")
157	(match_operator:QI 1 "ordered_comparison_operator"
158	 [(match_operand:QHPSI 2 "mra_operand" "RraSd")
159	  (match_operand:QHPSI 3 "mrai_operand" "RraSdi")]))]
160  "TARGET_A16"
161  "#"
162  "reload_completed"
163  [(set (reg:CC FLG_REGNO)
164	(compare (match_dup 2)
165		 (match_dup 3)))
166   (set (match_dup 0)
167	(match_op_dup 1 [(reg:CC FLG_REGNO) (const_int 0)]))]
168  ""
169  [(set_attr "flags" "x")]
170)
171
172(define_insn_and_split "cstore<mode>4_24"
173  [(set (match_operand:HI 0 "mra_nopp_operand" "=RhiSd")
174	(match_operator:HI 1 "ordered_comparison_operator"
175	 [(match_operand:QHPSI 2 "mra_operand" "RraSd")
176	  (match_operand:QHPSI 3 "mrai_operand" "RraSdi")]))]
177  "TARGET_A24"
178  "#"
179  "reload_completed"
180  [(set (reg:CC FLG_REGNO)
181	(compare (match_dup 2)
182		 (match_dup 3)))
183   (set (match_dup 0)
184	(match_op_dup 1 [(reg:CC FLG_REGNO) (const_int 0)]))]
185  ""
186  [(set_attr "flags" "x")]
187)
188
189(define_insn_and_split "movqicc_<code>_<mode>"
190  [(set (match_operand:QI 0 "register_operand" "=R0w")
191        (if_then_else:QI (eqne_cond:QI (match_operand:QHPSI 1 "mra_operand" "RraSd")
192				       (match_operand:QHPSI 2 "mrai_operand" "RraSdi"))
193			  (match_operand:QI 3 "const_int_operand" "")
194			  (match_operand:QI 4 "const_int_operand" "")))]
195  ""
196  "#"
197  "reload_completed"
198  [(set (reg:CC FLG_REGNO)
199	(compare (match_dup 1)
200		 (match_dup 2)))
201   (set (match_dup 0)
202        (if_then_else:QI (eqne_cond:QI (reg:CC FLG_REGNO) (const_int 0))
203			 (match_dup 3)
204			 (match_dup 4)))]
205  ""
206  [(set_attr "flags" "x")]
207  )
208
209(define_insn_and_split "movhicc_<code>_<mode>"
210  [(set (match_operand:HI 0 "register_operand" "=R0w")
211        (if_then_else:HI (eqne_cond:HI (match_operand:QHPSI 1 "mra_operand" "RraSd")
212				       (match_operand:QHPSI 2 "mrai_operand" "RraSdi"))
213			  (match_operand:QI 3 "const_int_operand" "")
214			  (match_operand:QI 4 "const_int_operand" "")))]
215  "TARGET_A24"
216  "#"
217  "reload_completed"
218  [(set (reg:CC FLG_REGNO)
219	(compare (match_dup 1)
220		 (match_dup 2)))
221   (set (match_dup 0)
222        (if_then_else:HI (eqne_cond:HI (reg:CC FLG_REGNO) (const_int 0))
223			 (match_dup 3)
224			 (match_dup 4)))]
225  ""
226  [(set_attr "flags" "x")]
227  )
228
229;; And these are the expanders.
230
231(define_expand "movqicc"
232  [(set (match_operand:QI 0 "register_operand" "")
233        (if_then_else:QI (match_operand 1 "m32c_eqne_operator" "")
234                         (match_operand:QI 2 "const_int_operand" "")
235                         (match_operand:QI 3 "const_int_operand" "")))]
236  ""
237  "if (m32c_expand_movcc(operands))
238     FAIL;
239   DONE;"
240)
241
242(define_expand "movhicc"
243  [(set (match_operand:HI 0 "mra_operand" "")
244        (if_then_else:HI (match_operand 1 "m32c_eqne_operator" "")
245                         (match_operand:HI 2 "const_int_operand" "")
246                         (match_operand:HI 3 "const_int_operand" "")))]
247  "TARGET_A24"
248  "if (m32c_expand_movcc(operands))
249     FAIL;
250   DONE;"
251)
252
253
254;; CMP opcodes subtract two values, set the flags, and discard the
255;; value.  This pattern recovers the sign of the discarded value based
256;; on the flags.  Operand 0 is set to -1, 0, or 1.  This is used for
257;; the cmpstr pattern.  For optimal code, this should be removed if
258;; followed by a suitable CMP insn (see the peephole following).  This
259;; pattern is 7 bytes and 5 cycles.  If you don't need specific
260;; values, a 5/4 pattern can be made with SCGT and BMLT to set the
261;; appropriate bits.
262
263(define_insn "cond_to_int"
264  [(set (match_operand:HI 0 "mra_qi_operand" "=Rqi")
265	(if_then_else:HI (lt (reg:CC FLG_REGNO) (const_int 0))
266			 (const_int -1)
267			 (if_then_else:HI (eq (reg:CC FLG_REGNO) (const_int 0))
268					  (const_int 0)
269					  (const_int -1))))]
270  "TARGET_A24"
271  "sceq\t%0\n\tbmgt\t1,%h0\n\tdec.w\t%0"
272  [(set_attr "flags" "x")]
273  )
274
275;; A cond_to_int followed by a compare against zero is essentially a
276;; no-op.  However, the result of the cond_to_int may be used by later
277;; insns, so make sure it's dead before deleting its set.
278
279(define_peephole2
280  [(set (match_operand:HI 0 "mra_qi_operand" "")
281	(if_then_else:HI (lt (reg:CC FLG_REGNO) (const_int 0))
282			 (const_int -1)
283			 (if_then_else:HI (eq (reg:CC FLG_REGNO) (const_int 0))
284					  (const_int 0)
285					  (const_int -1))))
286   (set (reg:CC FLG_REGNO)
287	(compare (match_operand:HI 1 "mra_qi_operand" "")
288		 (const_int 0)))
289   ]
290  "rtx_equal_p (operands[0], operands[1])
291     && dead_or_set_p (peep2_next_insn (1), operands[0])"
292  [(const_int 1)]
293  "")
294