1/* If-conversion header file.
2 Copyright (C) 2014-2017 Free Software Foundation, Inc.
3
4 This file is part of GCC.
5
6 GCC is free software; you can redistribute it and/or modify it
7 under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3, or (at your option)
9 any later version.
10
11 GCC is distributed in the hope that it will be useful, but WITHOUT
12 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
13 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
14 License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
19
20#ifndef GCC_IFCVT_H
21#define GCC_IFCVT_H
22
23/* Structure to group all of the information to process IF-THEN and
24 IF-THEN-ELSE blocks for the conditional execution support. */
25
26struct ce_if_block
27{
28 basic_block test_bb; /* First test block. */
29 basic_block then_bb; /* THEN block. */
30 basic_block else_bb; /* ELSE block or NULL. */
31 basic_block join_bb; /* Join THEN/ELSE blocks. */
32 basic_block last_test_bb; /* Last bb to hold && or || tests. */
33 int num_multiple_test_blocks; /* # of && and || basic blocks. */
34 int num_and_and_blocks; /* # of && blocks. */
35 int num_or_or_blocks; /* # of || blocks. */
36 int num_multiple_test_insns; /* # of insns in && and || blocks. */
37 int and_and_p; /* Complex test is &&. */
38 int num_then_insns; /* # of insns in THEN block. */
39 int num_else_insns; /* # of insns in ELSE block. */
40 int pass; /* Pass number. */
41};
42
43/* Used by noce_process_if_block to communicate with its subroutines.
44
45 The subroutines know that A and B may be evaluated freely. They
46 know that X is a register. They should insert new instructions
47 before cond_earliest. */
48
49struct noce_if_info
50{
51 /* The basic blocks that make up the IF-THEN-{ELSE-,}JOIN block. */
52 basic_block test_bb, then_bb, else_bb, join_bb;
53
54 /* The jump that ends TEST_BB. */
55 rtx_insn *jump;
56
57 /* The jump condition. */
58 rtx cond;
59
60 /* Reversed jump condition. */
61 rtx rev_cond;
62
63 /* New insns should be inserted before this one. */
64 rtx_insn *cond_earliest;
65
66 /* Insns in the THEN and ELSE block. There is always just this
67 one insns in those blocks. The insns are single_set insns.
68 If there was no ELSE block, INSN_B is the last insn before
69 COND_EARLIEST, or NULL_RTX. In the former case, the insn
70 operands are still valid, as if INSN_B was moved down below
71 the jump. */
72 rtx_insn *insn_a, *insn_b;
73
74 /* The SET_SRC of INSN_A and INSN_B. */
75 rtx a, b;
76
77 /* The SET_DEST of INSN_A. */
78 rtx x;
79
80 /* The original set destination that the THEN and ELSE basic blocks finally
81 write their result to. */
82 rtx orig_x;
83 /* True if this if block is not canonical. In the canonical form of
84 if blocks, the THEN_BB is the block reached via the fallthru edge
85 from TEST_BB. For the noce transformations, we allow the symmetric
86 form as well. */
87 bool then_else_reversed;
88
89 /* True if the contents of then_bb and else_bb are a
90 simple single set instruction. */
91 bool then_simple;
92 bool else_simple;
93
94 /* True if we're optimisizing the control block for speed, false if
95 we're optimizing for size. */
96 bool speed_p;
97
98 /* An estimate of the original costs. When optimizing for size, this is the
99 combined cost of COND, JUMP and the costs for THEN_BB and ELSE_BB.
100 When optimizing for speed, we use the costs of COND plus the minimum of
101 the costs for THEN_BB and ELSE_BB, as computed in the next field. */
102 unsigned int original_cost;
103
104 /* Maximum permissible cost for the unconditional sequence we should
105 generate to replace this branch. */
106 unsigned int max_seq_cost;
107
108 /* The name of the noce transform that succeeded in if-converting
109 this structure. Used for debugging. */
110 const char *transform_name;
111};
112
113#endif /* GCC_IFCVT_H */
114