1  /* If-conversion header file.
       2     Copyright (C) 2014-2023 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  
      26  struct 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  
      49  struct 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 THEN_BB is conditional on !COND rather than COND.
      90       This is used if:
      91  
      92       - JUMP branches to THEN_BB on COND
      93       - JUMP falls through to JOIN_BB on !COND
      94       - COND cannot be reversed.  */
      95    bool cond_inverted;
      96  
      97    /* True if the contents of then_bb and else_bb are a
      98       simple single set instruction.  */
      99    bool then_simple;
     100    bool else_simple;
     101  
     102    /* True if we're optimisizing the control block for speed, false if
     103       we're optimizing for size.  */
     104    bool speed_p;
     105  
     106    /* An estimate of the original costs.  When optimizing for size, this is the
     107       combined cost of COND, JUMP and the costs for THEN_BB and ELSE_BB.
     108       When optimizing for speed, we use the costs of COND plus weighted average
     109       of the costs for THEN_BB and ELSE_BB, as computed in the next field.  */
     110    unsigned int original_cost;
     111  
     112    /* Maximum permissible cost for the unconditional sequence we should
     113       generate to replace this branch.  */
     114    unsigned int max_seq_cost;
     115  
     116    /* The name of the noce transform that succeeded in if-converting
     117       this structure.  Used for debugging.  */
     118    const char *transform_name;
     119  };
     120  
     121  #endif /* GCC_IFCVT_H */