/* If-conversion support.
- Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc.
+ Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005
+ Free Software Foundation, Inc.
This file is part of GCC.
#include "config.h"
#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
#include "rtl.h"
#include "regs.h"
#include "flags.h"
#include "insn-config.h"
#include "recog.h"
+#include "except.h"
#include "hard-reg-set.h"
#include "basic-block.h"
#include "expr.h"
#include "real.h"
#include "output.h"
+#include "optabs.h"
#include "toplev.h"
#include "tm_p.h"
+#include "cfgloop.h"
+#include "target.h"
#ifndef HAVE_conditional_execution
#define MAX_CONDITIONAL_EXECUTE (BRANCH_COST + 1)
#endif
-#define NULL_EDGE ((struct edge_def *)NULL)
-#define NULL_BLOCK ((struct basic_block_def *)NULL)
+#define NULL_EDGE ((edge) NULL)
+#define NULL_BLOCK ((basic_block) NULL)
/* # of IF-THEN or IF-THEN-ELSE blocks we looked at */
static int num_possible_if_blocks;
execution. */
static int num_updated_if_blocks;
-/* # of basic blocks that were removed. */
-static int num_removed_blocks;
+/* # of changes made which require life information to be updated. */
+static int num_true_changes;
+
+/* Whether conditional execution changes were made. */
+static int cond_exec_changed_p;
/* True if life data ok at present. */
static bool life_data_ok;
-/* The post-dominator relation on the original block numbers. */
-static sbitmap *post_dominators;
-
/* Forward references. */
-static int count_bb_insns PARAMS ((basic_block));
-static rtx first_active_insn PARAMS ((basic_block));
-static int last_active_insn_p PARAMS ((basic_block, rtx));
-static int seq_contains_jump PARAMS ((rtx));
-
-static int cond_exec_process_insns PARAMS ((rtx, rtx, rtx, rtx, int));
-static rtx cond_exec_get_condition PARAMS ((rtx));
-static int cond_exec_process_if_block PARAMS ((basic_block, basic_block,
- basic_block, basic_block));
-
-static rtx noce_get_condition PARAMS ((rtx, rtx *));
-static int noce_operand_ok PARAMS ((rtx));
-static int noce_process_if_block PARAMS ((basic_block, basic_block,
- basic_block, basic_block));
-
-static int process_if_block PARAMS ((basic_block, basic_block,
- basic_block, basic_block));
-static void merge_if_block PARAMS ((basic_block, basic_block,
- basic_block, basic_block));
-
-static int find_if_header PARAMS ((basic_block));
-static int find_if_block PARAMS ((basic_block, edge, edge));
-static int find_if_case_1 PARAMS ((basic_block, edge, edge));
-static int find_if_case_2 PARAMS ((basic_block, edge, edge));
-static int find_cond_trap PARAMS ((basic_block, edge, edge));
-static int find_memory PARAMS ((rtx *, void *));
-static int dead_or_predicable PARAMS ((basic_block, basic_block,
- basic_block, basic_block, int));
-static void noce_emit_move_insn PARAMS ((rtx, rtx));
-\f
-/* Abuse the basic_block AUX field to store the original block index,
- as well as a flag indicating that the block should be rescaned for
- life analysis. */
-
-#define SET_ORIG_INDEX(BB,I) ((BB)->aux = (void *)((size_t)(I)))
-#define ORIG_INDEX(BB) ((size_t)(BB)->aux)
-
+static int count_bb_insns (basic_block);
+static bool cheap_bb_rtx_cost_p (basic_block, int);
+static rtx first_active_insn (basic_block);
+static rtx last_active_insn (basic_block, int);
+static basic_block block_fallthru (basic_block);
+static int cond_exec_process_insns (ce_if_block_t *, rtx, rtx, rtx, rtx, int);
+static rtx cond_exec_get_condition (rtx);
+static int cond_exec_process_if_block (ce_if_block_t *, int);
+static rtx noce_get_condition (rtx, rtx *);
+static int noce_operand_ok (rtx);
+static int noce_process_if_block (ce_if_block_t *);
+static int process_if_block (ce_if_block_t *);
+static void merge_if_block (ce_if_block_t *);
+static int find_cond_trap (basic_block, edge, edge);
+static basic_block find_if_header (basic_block, int);
+static int block_jumps_and_fallthru_p (basic_block, basic_block);
+static int find_if_block (ce_if_block_t *);
+static int find_if_case_1 (basic_block, edge, edge);
+static int find_if_case_2 (basic_block, edge, edge);
+static int find_memory (rtx *, void *);
+static int dead_or_predicable (basic_block, basic_block, basic_block,
+ basic_block, int);
+static void noce_emit_move_insn (rtx, rtx);
+static rtx block_has_only_trap (basic_block);
\f
/* Count the number of non-jump active insns in BB. */
static int
-count_bb_insns (bb)
- basic_block bb;
+count_bb_insns (basic_block bb)
{
int count = 0;
- rtx insn = bb->head;
+ rtx insn = BB_HEAD (bb);
while (1)
{
- if (GET_CODE (insn) == CALL_INSN || GET_CODE (insn) == INSN)
+ if (CALL_P (insn) || NONJUMP_INSN_P (insn))
count++;
- if (insn == bb->end)
+ if (insn == BB_END (bb))
break;
insn = NEXT_INSN (insn);
}
return count;
}
+/* Determine whether the total insn_rtx_cost on non-jump insns in
+ basic block BB is less than MAX_COST. This function returns
+ false if the cost of any instruction could not be estimated. */
+
+static bool
+cheap_bb_rtx_cost_p (basic_block bb, int max_cost)
+{
+ int count = 0;
+ rtx insn = BB_HEAD (bb);
+
+ while (1)
+ {
+ if (NONJUMP_INSN_P (insn))
+ {
+ int cost = insn_rtx_cost (PATTERN (insn));
+ if (cost == 0)
+ return false;
+
+ /* If this instruction is the load or set of a "stack" register,
+ such as a floating point register on x87, then the cost of
+ speculatively executing this instruction needs to include
+ the additional cost of popping this register off of the
+ register stack. */
+#ifdef STACK_REGS
+ {
+ rtx set = single_set (insn);
+ if (set && STACK_REG_P (SET_DEST (set)))
+ cost += COSTS_N_INSNS (1);
+ }
+#endif
+
+ count += cost;
+ if (count >= max_cost)
+ return false;
+ }
+ else if (CALL_P (insn))
+ return false;
+
+ if (insn == BB_END (bb))
+ break;
+ insn = NEXT_INSN (insn);
+ }
+
+ return true;
+}
+
/* Return the first non-jump active insn in the basic block. */
static rtx
-first_active_insn (bb)
- basic_block bb;
+first_active_insn (basic_block bb)
{
- rtx insn = bb->head;
+ rtx insn = BB_HEAD (bb);
- if (GET_CODE (insn) == CODE_LABEL)
+ if (LABEL_P (insn))
{
- if (insn == bb->end)
+ if (insn == BB_END (bb))
return NULL_RTX;
insn = NEXT_INSN (insn);
}
- while (GET_CODE (insn) == NOTE)
+ while (NOTE_P (insn))
{
- if (insn == bb->end)
+ if (insn == BB_END (bb))
return NULL_RTX;
insn = NEXT_INSN (insn);
}
- if (GET_CODE (insn) == JUMP_INSN)
+ if (JUMP_P (insn))
return NULL_RTX;
return insn;
}
-/* Return true if INSN is the last active non-jump insn in BB. */
+/* Return the last non-jump active (non-jump) insn in the basic block. */
-static int
-last_active_insn_p (bb, insn)
- basic_block bb;
- rtx insn;
+static rtx
+last_active_insn (basic_block bb, int skip_use_p)
{
- do
+ rtx insn = BB_END (bb);
+ rtx head = BB_HEAD (bb);
+
+ while (NOTE_P (insn)
+ || JUMP_P (insn)
+ || (skip_use_p
+ && NONJUMP_INSN_P (insn)
+ && GET_CODE (PATTERN (insn)) == USE))
{
- if (insn == bb->end)
- return TRUE;
- insn = NEXT_INSN (insn);
+ if (insn == head)
+ return NULL_RTX;
+ insn = PREV_INSN (insn);
}
- while (GET_CODE (insn) == NOTE);
- return GET_CODE (insn) == JUMP_INSN;
+ if (LABEL_P (insn))
+ return NULL_RTX;
+
+ return insn;
}
-/* It is possible, especially when having dealt with multi-word
- arithmetic, for the expanders to have emitted jumps. Search
- through the sequence and return TRUE if a jump exists so that
- we can abort the conversion. */
+/* Return the basic block reached by falling though the basic block BB. */
-static int
-seq_contains_jump (insn)
- rtx insn;
+static basic_block
+block_fallthru (basic_block bb)
{
- while (insn)
- {
- if (GET_CODE (insn) == JUMP_INSN)
- return 1;
- insn = NEXT_INSN (insn);
- }
- return 0;
+ edge e;
+ edge_iterator ei;
+
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ if (e->flags & EDGE_FALLTHRU)
+ break;
+
+ return (e) ? e->dest : NULL_BLOCK;
}
\f
/* Go through a bunch of insns, converting them to conditional
insns were processed. */
static int
-cond_exec_process_insns (start, end, test, prob_val, mod_ok)
- rtx start; /* first insn to look at */
- rtx end; /* last insn to look at */
- rtx test; /* conditional execution test */
- rtx prob_val; /* probability of branch taken. */
- int mod_ok; /* true if modifications ok last insn. */
+cond_exec_process_insns (ce_if_block_t *ce_info ATTRIBUTE_UNUSED,
+ /* if block information */rtx start,
+ /* first insn to look at */rtx end,
+ /* last insn to look at */rtx test,
+ /* conditional execution test */rtx prob_val,
+ /* probability of branch taken. */int mod_ok)
{
int must_be_last = FALSE;
rtx insn;
+ rtx xtest;
rtx pattern;
+ if (!start || !end)
+ return FALSE;
+
for (insn = start; ; insn = NEXT_INSN (insn))
{
- if (GET_CODE (insn) == NOTE)
+ if (NOTE_P (insn))
goto insn_done;
- if (GET_CODE (insn) != INSN && GET_CODE (insn) != CALL_INSN)
+ if (!NONJUMP_INSN_P (insn) && !CALL_P (insn))
abort ();
/* Remove USE insns that get in the way. */
if (reload_completed && GET_CODE (PATTERN (insn)) == USE)
{
- /* ??? Ug. Actually unlinking the thing is problematic,
+ /* ??? Ug. Actually unlinking the thing is problematic,
given what we'd have to coordinate with our callers. */
- PUT_CODE (insn, NOTE);
- NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
- NOTE_SOURCE_FILE (insn) = 0;
+ SET_INSN_DELETED (insn);
goto insn_done;
}
/* Now build the conditional form of the instruction. */
pattern = PATTERN (insn);
+ xtest = copy_rtx (test);
+
+ /* If this is already a COND_EXEC, rewrite the test to be an AND of the
+ two conditions. */
+ if (GET_CODE (pattern) == COND_EXEC)
+ {
+ if (GET_MODE (xtest) != GET_MODE (COND_EXEC_TEST (pattern)))
+ return FALSE;
+
+ xtest = gen_rtx_AND (GET_MODE (xtest), xtest,
+ COND_EXEC_TEST (pattern));
+ pattern = COND_EXEC_CODE (pattern);
+ }
+
+ pattern = gen_rtx_COND_EXEC (VOIDmode, xtest, pattern);
/* If the machine needs to modify the insn being conditionally executed,
say for example to force a constant integer operand into a temp
register, do so here. */
#ifdef IFCVT_MODIFY_INSN
- IFCVT_MODIFY_INSN (pattern, insn);
+ IFCVT_MODIFY_INSN (ce_info, pattern, insn);
if (! pattern)
return FALSE;
#endif
- validate_change (insn, &PATTERN (insn),
- gen_rtx_COND_EXEC (VOIDmode, copy_rtx (test),
- pattern), 1);
+ validate_change (insn, &PATTERN (insn), pattern, 1);
- if (GET_CODE (insn) == CALL_INSN && prob_val)
+ if (CALL_P (insn) && prob_val)
validate_change (insn, ®_NOTES (insn),
alloc_EXPR_LIST (REG_BR_PROB, prob_val,
REG_NOTES (insn)), 1);
/* Return the condition for a jump. Do not do any special processing. */
static rtx
-cond_exec_get_condition (jump)
- rtx jump;
+cond_exec_get_condition (rtx jump)
{
rtx test_if, cond;
/* Given a simple IF-THEN or IF-THEN-ELSE block, attempt to convert it
to conditional execution. Return TRUE if we were successful at
- converting the the block. */
+ converting the block. */
static int
-cond_exec_process_if_block (test_bb, then_bb, else_bb, join_bb)
- basic_block test_bb; /* Basic block test is in */
- basic_block then_bb; /* Basic block for THEN block */
- basic_block else_bb; /* Basic block for ELSE block */
- basic_block join_bb; /* Basic block the join label is in */
+cond_exec_process_if_block (ce_if_block_t * ce_info,
+ /* if block information */int do_multiple_p)
{
+ basic_block test_bb = ce_info->test_bb; /* last test block */
+ basic_block then_bb = ce_info->then_bb; /* THEN */
+ basic_block else_bb = ce_info->else_bb; /* ELSE or NULL */
rtx test_expr; /* expression in IF_THEN_ELSE that is tested */
rtx then_start; /* first insn in THEN block */
rtx then_end; /* last insn + 1 in THEN block */
int n_insns;
enum rtx_code false_code;
+ /* If test is comprised of && or || elements, and we've failed at handling
+ all of them together, just use the last test if it is the special case of
+ && elements without an ELSE block. */
+ if (!do_multiple_p && ce_info->num_multiple_test_blocks)
+ {
+ if (else_bb || ! ce_info->and_and_p)
+ return FALSE;
+
+ ce_info->test_bb = test_bb = ce_info->last_test_bb;
+ ce_info->num_multiple_test_blocks = 0;
+ ce_info->num_and_and_blocks = 0;
+ ce_info->num_or_or_blocks = 0;
+ }
+
/* Find the conditional jump to the ELSE or JOIN part, and isolate
the test. */
- test_expr = cond_exec_get_condition (test_bb->end);
+ test_expr = cond_exec_get_condition (BB_END (test_bb));
if (! test_expr)
return FALSE;
/* If the conditional jump is more than just a conditional jump,
then we can not do conditional execution conversion on this block. */
- if (!onlyjump_p (test_bb->end))
+ if (! onlyjump_p (BB_END (test_bb)))
return FALSE;
- /* Collect the bounds of where we're to search. */
-
- then_start = then_bb->head;
- then_end = then_bb->end;
-
- /* Skip a label heading THEN block. */
- if (GET_CODE (then_start) == CODE_LABEL)
- then_start = NEXT_INSN (then_start);
-
- /* Skip a (use (const_int 0)) or branch as the final insn. */
- if (GET_CODE (then_end) == INSN
- && GET_CODE (PATTERN (then_end)) == USE
- && GET_CODE (XEXP (PATTERN (then_end), 0)) == CONST_INT)
- then_end = PREV_INSN (then_end);
- else if (GET_CODE (then_end) == JUMP_INSN)
- then_end = PREV_INSN (then_end);
+ /* Collect the bounds of where we're to search, skipping any labels, jumps
+ and notes at the beginning and end of the block. Then count the total
+ number of insns and see if it is small enough to convert. */
+ then_start = first_active_insn (then_bb);
+ then_end = last_active_insn (then_bb, TRUE);
+ n_insns = ce_info->num_then_insns = count_bb_insns (then_bb);
+ max = MAX_CONDITIONAL_EXECUTE;
if (else_bb)
{
- /* Skip the ELSE block's label. */
- else_start = NEXT_INSN (else_bb->head);
- else_end = else_bb->end;
-
- /* Skip a (use (const_int 0)) or branch as the final insn. */
- if (GET_CODE (else_end) == INSN
- && GET_CODE (PATTERN (else_end)) == USE
- && GET_CODE (XEXP (PATTERN (else_end), 0)) == CONST_INT)
- else_end = PREV_INSN (else_end);
- else if (GET_CODE (else_end) == JUMP_INSN)
- else_end = PREV_INSN (else_end);
+ max *= 2;
+ else_start = first_active_insn (else_bb);
+ else_end = last_active_insn (else_bb, TRUE);
+ n_insns += ce_info->num_else_insns = count_bb_insns (else_bb);
}
- /* How many instructions should we convert in total? */
- n_insns = 0;
- if (else_bb)
- {
- max = 2 * MAX_CONDITIONAL_EXECUTE;
- n_insns = count_bb_insns (else_bb);
- }
- else
- max = MAX_CONDITIONAL_EXECUTE;
- n_insns += count_bb_insns (then_bb);
if (n_insns > max)
return FALSE;
/* Map test_expr/test_jump into the appropriate MD tests to use on
the conditionally executed code. */
-
+
true_expr = test_expr;
- false_code = reversed_comparison_code (true_expr, test_bb->end);
+ false_code = reversed_comparison_code (true_expr, BB_END (test_bb));
if (false_code != UNKNOWN)
false_expr = gen_rtx_fmt_ee (false_code, GET_MODE (true_expr),
XEXP (true_expr, 0), XEXP (true_expr, 1));
#ifdef IFCVT_MODIFY_TESTS
/* If the machine description needs to modify the tests, such as setting a
conditional execution register from a comparison, it can do so here. */
- IFCVT_MODIFY_TESTS (true_expr, false_expr, test_bb, then_bb, else_bb,
- join_bb);
+ IFCVT_MODIFY_TESTS (ce_info, true_expr, false_expr);
- /* See if the conversion failed */
+ /* See if the conversion failed. */
if (!true_expr || !false_expr)
goto fail;
#endif
- true_prob_val = find_reg_note (test_bb->end, REG_BR_PROB, NULL_RTX);
+ true_prob_val = find_reg_note (BB_END (test_bb), REG_BR_PROB, NULL_RTX);
if (true_prob_val)
{
true_prob_val = XEXP (true_prob_val, 0);
else
false_prob_val = NULL_RTX;
+ /* If we have && or || tests, do them here. These tests are in the adjacent
+ blocks after the first block containing the test. */
+ if (ce_info->num_multiple_test_blocks > 0)
+ {
+ basic_block bb = test_bb;
+ basic_block last_test_bb = ce_info->last_test_bb;
+
+ if (! false_expr)
+ goto fail;
+
+ do
+ {
+ rtx start, end;
+ rtx t, f;
+ enum rtx_code f_code;
+
+ bb = block_fallthru (bb);
+ start = first_active_insn (bb);
+ end = last_active_insn (bb, TRUE);
+ if (start
+ && ! cond_exec_process_insns (ce_info, start, end, false_expr,
+ false_prob_val, FALSE))
+ goto fail;
+
+ /* If the conditional jump is more than just a conditional jump, then
+ we can not do conditional execution conversion on this block. */
+ if (! onlyjump_p (BB_END (bb)))
+ goto fail;
+
+ /* Find the conditional jump and isolate the test. */
+ t = cond_exec_get_condition (BB_END (bb));
+ if (! t)
+ goto fail;
+
+ f_code = reversed_comparison_code (t, BB_END (bb));
+ if (f_code == UNKNOWN)
+ goto fail;
+
+ f = gen_rtx_fmt_ee (f_code, GET_MODE (t), XEXP (t, 0), XEXP (t, 1));
+ if (ce_info->and_and_p)
+ {
+ t = gen_rtx_AND (GET_MODE (t), true_expr, t);
+ f = gen_rtx_IOR (GET_MODE (t), false_expr, f);
+ }
+ else
+ {
+ t = gen_rtx_IOR (GET_MODE (t), true_expr, t);
+ f = gen_rtx_AND (GET_MODE (t), false_expr, f);
+ }
+
+ /* If the machine description needs to modify the tests, such as
+ setting a conditional execution register from a comparison, it can
+ do so here. */
+#ifdef IFCVT_MODIFY_MULTIPLE_TESTS
+ IFCVT_MODIFY_MULTIPLE_TESTS (ce_info, bb, t, f);
+
+ /* See if the conversion failed. */
+ if (!t || !f)
+ goto fail;
+#endif
+
+ true_expr = t;
+ false_expr = f;
+ }
+ while (bb != last_test_bb);
+ }
+
/* For IF-THEN-ELSE blocks, we don't allow modifications of the test
on then THEN block. */
then_mod_ok = (else_bb == NULL_BLOCK);
if (then_end
&& (! false_expr
- || ! cond_exec_process_insns (then_start, then_end, false_expr,
- false_prob_val, then_mod_ok)))
+ || ! cond_exec_process_insns (ce_info, then_start, then_end,
+ false_expr, false_prob_val,
+ then_mod_ok)))
goto fail;
- if (else_bb
- && ! cond_exec_process_insns (else_start, else_end,
+ if (else_bb && else_end
+ && ! cond_exec_process_insns (ce_info, else_start, else_end,
true_expr, true_prob_val, TRUE))
goto fail;
+ /* If we cannot apply the changes, fail. Do not go through the normal fail
+ processing, since apply_change_group will call cancel_changes. */
if (! apply_change_group ())
- return FALSE;
+ {
+#ifdef IFCVT_MODIFY_CANCEL
+ /* Cancel any machine dependent changes. */
+ IFCVT_MODIFY_CANCEL (ce_info);
+#endif
+ return FALSE;
+ }
#ifdef IFCVT_MODIFY_FINAL
- /* Do any machine dependent final modifications */
- IFCVT_MODIFY_FINAL (test_bb, then_bb, else_bb, join_bb);
+ /* Do any machine dependent final modifications. */
+ IFCVT_MODIFY_FINAL (ce_info);
#endif
/* Conversion succeeded. */
- if (rtl_dump_file)
- fprintf (rtl_dump_file, "%d insn%s converted to conditional execution.\n",
+ if (dump_file)
+ fprintf (dump_file, "%d insn%s converted to conditional execution.\n",
n_insns, (n_insns == 1) ? " was" : "s were");
/* Merge the blocks! */
- merge_if_block (test_bb, then_bb, else_bb, join_bb);
+ merge_if_block (ce_info);
+ cond_exec_changed_p = TRUE;
return TRUE;
fail:
#ifdef IFCVT_MODIFY_CANCEL
/* Cancel any machine dependent changes. */
- IFCVT_MODIFY_CANCEL (test_bb, then_bb, else_bb, join_bb);
+ IFCVT_MODIFY_CANCEL (ce_info);
#endif
cancel_changes (0);
return FALSE;
}
\f
-/* Used by noce_process_if_block to communicate with its subroutines.
+/* Used by noce_process_if_block to communicate with its subroutines.
The subroutines know that A and B may be evaluated freely. They
- know that X is a register. They should insert new instructions
+ know that X is a register. They should insert new instructions
before cond_earliest. */
struct noce_if_info
rtx insn_a, insn_b;
rtx x, a, b;
rtx jump, cond, cond_earliest;
+ /* True if "b" was originally evaluated unconditionally. */
+ bool b_unconditional;
};
-static rtx noce_emit_store_flag PARAMS ((struct noce_if_info *,
- rtx, int, int));
-static int noce_try_store_flag PARAMS ((struct noce_if_info *));
-static int noce_try_store_flag_inc PARAMS ((struct noce_if_info *));
-static int noce_try_store_flag_constants PARAMS ((struct noce_if_info *));
-static int noce_try_store_flag_mask PARAMS ((struct noce_if_info *));
-static rtx noce_emit_cmove PARAMS ((struct noce_if_info *,
- rtx, enum rtx_code, rtx,
- rtx, rtx, rtx));
-static int noce_try_cmove PARAMS ((struct noce_if_info *));
-static int noce_try_cmove_arith PARAMS ((struct noce_if_info *));
-static rtx noce_get_alt_condition PARAMS ((struct noce_if_info *,
- rtx, rtx *));
-static int noce_try_minmax PARAMS ((struct noce_if_info *));
-static int noce_try_abs PARAMS ((struct noce_if_info *));
+static rtx noce_emit_store_flag (struct noce_if_info *, rtx, int, int);
+static int noce_try_move (struct noce_if_info *);
+static int noce_try_store_flag (struct noce_if_info *);
+static int noce_try_addcc (struct noce_if_info *);
+static int noce_try_store_flag_constants (struct noce_if_info *);
+static int noce_try_store_flag_mask (struct noce_if_info *);
+static rtx noce_emit_cmove (struct noce_if_info *, rtx, enum rtx_code, rtx,
+ rtx, rtx, rtx);
+static int noce_try_cmove (struct noce_if_info *);
+static int noce_try_cmove_arith (struct noce_if_info *);
+static rtx noce_get_alt_condition (struct noce_if_info *, rtx, rtx *);
+static int noce_try_minmax (struct noce_if_info *);
+static int noce_try_abs (struct noce_if_info *);
+static int noce_try_sign_mask (struct noce_if_info *);
/* Helper function for noce_try_store_flag*. */
static rtx
-noce_emit_store_flag (if_info, x, reversep, normalize)
- struct noce_if_info *if_info;
- rtx x;
- int reversep, normalize;
+noce_emit_store_flag (struct noce_if_info *if_info, rtx x, int reversep,
+ int normalize)
{
rtx cond = if_info->cond;
int cond_complex;
{
tmp = get_insns ();
end_sequence ();
- emit_insns (tmp);
+ emit_insn (tmp);
if_info->cond_earliest = if_info->jump;
end_sequence ();
}
- /* Don't even try if the comparison operands are weird. */
- if (cond_complex)
+ /* Don't even try if the comparison operands or the mode of X are weird. */
+ if (cond_complex || !SCALAR_INT_MODE_P (GET_MODE (x)))
return NULL_RTX;
return emit_store_flag (x, code, XEXP (cond, 0),
|| code == GEU || code == GTU), normalize);
}
-/* Emit instruction to move an rtx into STRICT_LOW_PART. */
+/* Emit instruction to move an rtx, possibly into STRICT_LOW_PART.
+ X is the destination/target and Y is the value to copy. */
+
static void
-noce_emit_move_insn (x, y)
- rtx x, y;
+noce_emit_move_insn (rtx x, rtx y)
{
enum machine_mode outmode, inmode;
rtx outer, inner;
outmode = GET_MODE (outer);
inmode = GET_MODE (inner);
bitpos = SUBREG_BYTE (outer) * BITS_PER_UNIT;
- store_bit_field (inner, GET_MODE_BITSIZE (outmode), bitpos, outmode, y,
- GET_MODE_BITSIZE (inmode));
+ store_bit_field (inner, GET_MODE_BITSIZE (outmode), bitpos, outmode, y);
+}
+
+/* Return sequence of instructions generated by if conversion. This
+ function calls end_sequence() to end the current stream, ensures
+ that are instructions are unshared, recognizable non-jump insns.
+ On failure, this function returns a NULL_RTX. */
+
+static rtx
+end_ifcvt_sequence (struct noce_if_info *if_info)
+{
+ rtx insn;
+ rtx seq = get_insns ();
+
+ set_used_flags (if_info->x);
+ set_used_flags (if_info->cond);
+ unshare_all_rtl_in_chain (seq);
+ end_sequence ();
+
+ /* Make sure that all of the instructions emitted are recognizable,
+ and that we haven't introduced a new jump instruction.
+ As an exercise for the reader, build a general mechanism that
+ allows proper placement of required clobbers. */
+ for (insn = seq; insn; insn = NEXT_INSN (insn))
+ if (JUMP_P (insn)
+ || recog_memoized (insn) == -1)
+ return NULL_RTX;
+
+ return seq;
+}
+
+/* Convert "if (a != b) x = a; else x = b" into "x = a" and
+ "if (a == b) x = a; else x = b" into "x = b". */
+
+static int
+noce_try_move (struct noce_if_info *if_info)
+{
+ rtx cond = if_info->cond;
+ enum rtx_code code = GET_CODE (cond);
+ rtx y, seq;
+
+ if (code != NE && code != EQ)
+ return FALSE;
+
+ /* This optimization isn't valid if either A or B could be a NaN
+ or a signed zero. */
+ if (HONOR_NANS (GET_MODE (if_info->x))
+ || HONOR_SIGNED_ZEROS (GET_MODE (if_info->x)))
+ return FALSE;
+
+ /* Check whether the operands of the comparison are A and in
+ either order. */
+ if ((rtx_equal_p (if_info->a, XEXP (cond, 0))
+ && rtx_equal_p (if_info->b, XEXP (cond, 1)))
+ || (rtx_equal_p (if_info->a, XEXP (cond, 1))
+ && rtx_equal_p (if_info->b, XEXP (cond, 0))))
+ {
+ y = (code == EQ) ? if_info->a : if_info->b;
+
+ /* Avoid generating the move if the source is the destination. */
+ if (! rtx_equal_p (if_info->x, y))
+ {
+ start_sequence ();
+ noce_emit_move_insn (if_info->x, y);
+ seq = end_ifcvt_sequence (if_info);
+ if (!seq)
+ return FALSE;
+
+ emit_insn_before_setloc (seq, if_info->jump,
+ INSN_LOCATOR (if_info->insn_a));
+ }
+ return TRUE;
+ }
+ return FALSE;
}
/* Convert "if (test) x = 1; else x = 0".
a go at the conversion. */
static int
-noce_try_store_flag (if_info)
- struct noce_if_info *if_info;
+noce_try_store_flag (struct noce_if_info *if_info)
{
int reversep;
rtx target, seq;
if (target != if_info->x)
noce_emit_move_insn (if_info->x, target);
- seq = get_insns ();
- end_sequence ();
- emit_insns_before (seq, if_info->cond_earliest);
+ seq = end_ifcvt_sequence (if_info);
+ if (! seq)
+ return FALSE;
+ emit_insn_before_setloc (seq, if_info->jump,
+ INSN_LOCATOR (if_info->insn_a));
return TRUE;
}
else
/* Convert "if (test) x = a; else x = b", for A and B constant. */
static int
-noce_try_store_flag_constants (if_info)
- struct noce_if_info *if_info;
+noce_try_store_flag_constants (struct noce_if_info *if_info)
{
rtx target, seq;
int reversep;
return FALSE;
if (reversep)
- {
+ {
tmp = itrue; itrue = ifalse; ifalse = tmp;
diff = trunc_int_for_mode (-diff, mode);
}
if (target != if_info->x)
noce_emit_move_insn (if_info->x, target);
- seq = get_insns ();
- end_sequence ();
-
- if (seq_contains_jump (seq))
+ seq = end_ifcvt_sequence (if_info);
+ if (!seq)
return FALSE;
- emit_insns_before (seq, if_info->cond_earliest);
-
+ emit_insn_before_setloc (seq, if_info->jump,
+ INSN_LOCATOR (if_info->insn_a));
return TRUE;
}
return FALSE;
}
-/* Convert "if (test) foo++" into "foo += (test != 0)", and
+/* Convert "if (test) foo++" into "foo += (test != 0)", and
similarly for "foo--". */
static int
-noce_try_store_flag_inc (if_info)
- struct noce_if_info *if_info;
+noce_try_addcc (struct noce_if_info *if_info)
{
rtx target, seq;
int subtract, normalize;
if (! no_new_pseudos
- && (BRANCH_COST >= 2
- || HAVE_incscc
- || HAVE_decscc)
- /* Should be no `else' case to worry about. */
- && if_info->b == if_info->x
&& GET_CODE (if_info->a) == PLUS
- && (XEXP (if_info->a, 1) == const1_rtx
- || XEXP (if_info->a, 1) == constm1_rtx)
- && rtx_equal_p (XEXP (if_info->a, 0), if_info->x)
+ && rtx_equal_p (XEXP (if_info->a, 0), if_info->b)
&& (reversed_comparison_code (if_info->cond, if_info->jump)
!= UNKNOWN))
{
- if (STORE_FLAG_VALUE == INTVAL (XEXP (if_info->a, 1)))
- subtract = 0, normalize = 0;
- else if (-STORE_FLAG_VALUE == INTVAL (XEXP (if_info->a, 1)))
- subtract = 1, normalize = 0;
- else
- subtract = 0, normalize = INTVAL (XEXP (if_info->a, 1));
-
- start_sequence ();
-
- target = noce_emit_store_flag (if_info,
- gen_reg_rtx (GET_MODE (if_info->x)),
- 1, normalize);
+ rtx cond = if_info->cond;
+ enum rtx_code code = reversed_comparison_code (cond, if_info->jump);
- if (target)
- target = expand_simple_binop (GET_MODE (if_info->x),
- subtract ? MINUS : PLUS,
- if_info->x, target, if_info->x,
- 0, OPTAB_WIDEN);
- if (target)
+ /* First try to use addcc pattern. */
+ if (general_operand (XEXP (cond, 0), VOIDmode)
+ && general_operand (XEXP (cond, 1), VOIDmode))
{
- if (target != if_info->x)
- noce_emit_move_insn (if_info->x, target);
+ start_sequence ();
+ target = emit_conditional_add (if_info->x, code,
+ XEXP (cond, 0),
+ XEXP (cond, 1),
+ VOIDmode,
+ if_info->b,
+ XEXP (if_info->a, 1),
+ GET_MODE (if_info->x),
+ (code == LTU || code == GEU
+ || code == LEU || code == GTU));
+ if (target)
+ {
+ if (target != if_info->x)
+ noce_emit_move_insn (if_info->x, target);
+
+ seq = end_ifcvt_sequence (if_info);
+ if (!seq)
+ return FALSE;
- seq = get_insns ();
+ emit_insn_before_setloc (seq, if_info->jump,
+ INSN_LOCATOR (if_info->insn_a));
+ return TRUE;
+ }
end_sequence ();
+ }
- if (seq_contains_jump (seq))
- return FALSE;
+ /* If that fails, construct conditional increment or decrement using
+ setcc. */
+ if (BRANCH_COST >= 2
+ && (XEXP (if_info->a, 1) == const1_rtx
+ || XEXP (if_info->a, 1) == constm1_rtx))
+ {
+ start_sequence ();
+ if (STORE_FLAG_VALUE == INTVAL (XEXP (if_info->a, 1)))
+ subtract = 0, normalize = 0;
+ else if (-STORE_FLAG_VALUE == INTVAL (XEXP (if_info->a, 1)))
+ subtract = 1, normalize = 0;
+ else
+ subtract = 0, normalize = INTVAL (XEXP (if_info->a, 1));
+
+
+ target = noce_emit_store_flag (if_info,
+ gen_reg_rtx (GET_MODE (if_info->x)),
+ 1, normalize);
- emit_insns_before (seq, if_info->cond_earliest);
+ if (target)
+ target = expand_simple_binop (GET_MODE (if_info->x),
+ subtract ? MINUS : PLUS,
+ if_info->b, target, if_info->x,
+ 0, OPTAB_WIDEN);
+ if (target)
+ {
+ if (target != if_info->x)
+ noce_emit_move_insn (if_info->x, target);
- return TRUE;
- }
+ seq = end_ifcvt_sequence (if_info);
+ if (!seq)
+ return FALSE;
- end_sequence ();
+ emit_insn_before_setloc (seq, if_info->jump,
+ INSN_LOCATOR (if_info->insn_a));
+ return TRUE;
+ }
+ end_sequence ();
+ }
}
return FALSE;
/* Convert "if (test) x = 0;" to "x &= -(test == 0);" */
static int
-noce_try_store_flag_mask (if_info)
- struct noce_if_info *if_info;
+noce_try_store_flag_mask (struct noce_if_info *if_info)
{
rtx target, seq;
int reversep;
reversep, -1);
if (target)
target = expand_simple_binop (GET_MODE (if_info->x), AND,
- if_info->x, target, if_info->x, 0,
+ if_info->x,
+ target, if_info->x, 0,
OPTAB_WIDEN);
if (target)
if (target != if_info->x)
noce_emit_move_insn (if_info->x, target);
- seq = get_insns ();
- end_sequence ();
-
- if (seq_contains_jump (seq))
+ seq = end_ifcvt_sequence (if_info);
+ if (!seq)
return FALSE;
- emit_insns_before (seq, if_info->cond_earliest);
-
+ emit_insn_before_setloc (seq, if_info->jump,
+ INSN_LOCATOR (if_info->insn_a));
return TRUE;
}
/* Helper function for noce_try_cmove and noce_try_cmove_arith. */
static rtx
-noce_emit_cmove (if_info, x, code, cmp_a, cmp_b, vfalse, vtrue)
- struct noce_if_info *if_info;
- rtx x, cmp_a, cmp_b, vfalse, vtrue;
- enum rtx_code code;
+noce_emit_cmove (struct noce_if_info *if_info, rtx x, enum rtx_code code,
+ rtx cmp_a, rtx cmp_b, rtx vfalse, rtx vtrue)
{
/* If earliest == jump, try to build the cmove insn directly.
This is helpful when combine has created some complex condition
{
tmp = get_insns ();
end_sequence ();
- emit_insns (tmp);
+ emit_insn (tmp);
return x;
}
#else
/* We'll never get here, as noce_process_if_block doesn't call the
functions involved. Ifdef code, however, should be discouraged
- because it leads to typos in the code not selected. However,
+ because it leads to typos in the code not selected. However,
emit_conditional_move won't exist either. */
return NULL_RTX;
#endif
has had a go at it. */
static int
-noce_try_cmove (if_info)
- struct noce_if_info *if_info;
+noce_try_cmove (struct noce_if_info *if_info)
{
enum rtx_code code;
rtx target, seq;
if (target != if_info->x)
noce_emit_move_insn (if_info->x, target);
- seq = get_insns ();
- end_sequence ();
- emit_insns_before (seq, if_info->cond_earliest);
+ seq = end_ifcvt_sequence (if_info);
+ if (!seq)
+ return FALSE;
+
+ emit_insn_before_setloc (seq, if_info->jump,
+ INSN_LOCATOR (if_info->insn_a));
return TRUE;
}
else
/* Try more complex cases involving conditional_move. */
static int
-noce_try_cmove_arith (if_info)
- struct noce_if_info *if_info;
+noce_try_cmove_arith (struct noce_if_info *if_info)
{
rtx a = if_info->a;
rtx b = if_info->b;
rtx x = if_info->x;
+ rtx orig_a, orig_b;
rtx insn_a, insn_b;
rtx tmp, target;
int is_mem = 0;
+ int insn_cost;
enum rtx_code code;
/* A conditional move from two memory sources is equivalent to a
early because it'll screw alias analysis. Note that we've
already checked for no side effects. */
if (! no_new_pseudos && cse_not_expected
- && GET_CODE (a) == MEM && GET_CODE (b) == MEM
+ && MEM_P (a) && MEM_P (b)
&& BRANCH_COST >= 5)
{
a = XEXP (a, 0);
if (test)
x = y;
*/
-
+
code = GET_CODE (if_info->cond);
insn_a = if_info->insn_a;
insn_b = if_info->insn_b;
+ /* Total insn_rtx_cost should be smaller than branch cost. Exit
+ if insn_rtx_cost can't be estimated. */
+ if (insn_a)
+ {
+ insn_cost = insn_rtx_cost (PATTERN (insn_a));
+ if (insn_cost == 0 || insn_cost > COSTS_N_INSNS (BRANCH_COST))
+ return FALSE;
+ }
+ else
+ {
+ insn_cost = 0;
+ }
+
+ if (insn_b) {
+ insn_cost += insn_rtx_cost (PATTERN (insn_b));
+ if (insn_cost == 0 || insn_cost > COSTS_N_INSNS (BRANCH_COST))
+ return FALSE;
+ }
+
/* Possibly rearrange operands to make things come out more natural. */
if (reversed_comparison_code (if_info->cond, if_info->jump) != UNKNOWN)
{
start_sequence ();
+ orig_a = a;
+ orig_b = b;
+
/* If either operand is complex, load it into a register first.
The best way to do this is to copy the original insn. In this
- way we preserve any clobbers etc that the insn may have had.
+ way we preserve any clobbers etc that the insn may have had.
This is of course not possible in the IS_MEM case. */
if (! general_operand (a, GET_MODE (a)))
{
}
if (! general_operand (b, GET_MODE (b)))
{
- rtx set;
+ rtx set, last;
if (no_new_pseudos)
goto end_seq_and_fail;
if (is_mem)
{
tmp = gen_reg_rtx (GET_MODE (b));
- tmp = emit_insn (gen_rtx_SET (VOIDmode, tmp, b));
+ tmp = gen_rtx_SET (VOIDmode, tmp, b);
}
else if (! insn_b)
goto end_seq_and_fail;
tmp = copy_rtx (insn_b);
set = single_set (tmp);
SET_DEST (set) = b;
- tmp = emit_insn (PATTERN (tmp));
+ tmp = PATTERN (tmp);
}
+
+ /* If insn to set up A clobbers any registers B depends on, try to
+ swap insn that sets up A with the one that sets up B. If even
+ that doesn't help, punt. */
+ last = get_last_insn ();
+ if (last && modified_in_p (orig_b, last))
+ {
+ tmp = emit_insn_before (tmp, get_insns ());
+ if (modified_in_p (orig_a, tmp))
+ goto end_seq_and_fail;
+ }
+ else
+ tmp = emit_insn (tmp);
+
if (recog_memoized (tmp) < 0)
goto end_seq_and_fail;
}
else if (target != x)
noce_emit_move_insn (x, target);
- tmp = get_insns ();
- end_sequence ();
- emit_insns_before (tmp, if_info->cond_earliest);
+ tmp = end_ifcvt_sequence (if_info);
+ if (!tmp)
+ return FALSE;
+
+ emit_insn_before_setloc (tmp, if_info->jump, INSN_LOCATOR (if_info->insn_a));
return TRUE;
end_seq_and_fail:
For these we wish to know that it is A or B in the condition. */
static rtx
-noce_get_alt_condition (if_info, target, earliest)
- struct noce_if_info *if_info;
- rtx target;
- rtx *earliest;
+noce_get_alt_condition (struct noce_if_info *if_info, rtx target,
+ rtx *earliest)
{
rtx cond, set, insn;
int reverse;
}
cond = canonicalize_condition (if_info->jump, cond, reverse,
- earliest, target);
+ earliest, target, false, true);
if (! cond || ! reg_mentioned_p (target, cond))
return NULL;
/* X may not be mentioned in the range (cond_earliest, jump]. */
for (insn = if_info->jump; insn != *earliest; insn = PREV_INSN (insn))
- if (INSN_P (insn) && reg_mentioned_p (if_info->x, insn))
+ if (INSN_P (insn) && reg_overlap_mentioned_p (if_info->x, PATTERN (insn)))
return NULL;
/* A and B may not be modified in the range [cond_earliest, jump). */
/* Convert "if (a < b) x = a; else x = b;" to "x = min(a, b);", etc. */
static int
-noce_try_minmax (if_info)
- struct noce_if_info *if_info;
-{
+noce_try_minmax (struct noce_if_info *if_info)
+{
rtx cond, earliest, target, seq;
enum rtx_code code, op;
int unsignedp;
if (target != if_info->x)
noce_emit_move_insn (if_info->x, target);
- seq = get_insns ();
- end_sequence ();
-
- if (seq_contains_jump (seq))
+ seq = end_ifcvt_sequence (if_info);
+ if (!seq)
return FALSE;
- emit_insns_before (seq, earliest);
+ emit_insn_before_setloc (seq, if_info->jump, INSN_LOCATOR (if_info->insn_a));
if_info->cond = cond;
if_info->cond_earliest = earliest;
/* Convert "if (a < 0) x = -a; else x = a;" to "x = abs(a);", etc. */
static int
-noce_try_abs (if_info)
- struct noce_if_info *if_info;
-{
+noce_try_abs (struct noce_if_info *if_info)
+{
rtx cond, earliest, target, seq, a, b, c;
int negate;
}
else
return FALSE;
-
+
cond = noce_get_alt_condition (if_info, b, &earliest);
if (!cond)
return FALSE;
{
rtx insn, note = NULL;
for (insn = earliest;
- insn != if_info->test_bb->head;
+ insn != BB_HEAD (if_info->test_bb);
insn = PREV_INSN (insn))
- if (INSN_P (insn)
+ if (INSN_P (insn)
&& ((note = find_reg_note (insn, REG_EQUAL, c))
|| (note = find_reg_note (insn, REG_EQUIV, c))))
break;
return FALSE;
c = XEXP (note, 0);
}
- if (GET_CODE (c) == MEM
+ if (MEM_P (c)
&& GET_CODE (XEXP (c, 0)) == SYMBOL_REF
&& CONSTANT_POOL_ADDRESS_P (XEXP (c, 0)))
c = get_pool_constant (XEXP (c, 0));
/* Work around funny ideas get_condition has wrt canonicalization.
- Note that these rtx constants are known to be CONST_INT, and
+ Note that these rtx constants are known to be CONST_INT, and
therefore imply integer comparisons. */
if (c == constm1_rtx && GET_CODE (cond) == GT)
;
start_sequence ();
- target = expand_simple_unop (GET_MODE (if_info->x), ABS, b, if_info->x, 0);
+ target = expand_abs_nojump (GET_MODE (if_info->x), b, if_info->x, 1);
- /* ??? It's a quandry whether cmove would be better here, especially
+ /* ??? It's a quandary whether cmove would be better here, especially
for integers. Perhaps combine will clean things up. */
if (target && negate)
target = expand_simple_unop (GET_MODE (target), NEG, target, if_info->x, 0);
if (target != if_info->x)
noce_emit_move_insn (if_info->x, target);
- seq = get_insns ();
- end_sequence ();
-
- if (seq_contains_jump (seq))
+ seq = end_ifcvt_sequence (if_info);
+ if (!seq)
return FALSE;
- emit_insns_before (seq, earliest);
+ emit_insn_before_setloc (seq, if_info->jump, INSN_LOCATOR (if_info->insn_a));
if_info->cond = cond;
if_info->cond_earliest = earliest;
return TRUE;
}
-/* Look for the condition for the jump first. We'd prefer to avoid
- get_condition if we can -- it tries to look back for the contents
- of an original compare. On targets that use normal integers for
- comparisons, e.g. alpha, this is wasteful. */
+/* Convert "if (m < 0) x = b; else x = 0;" to "x = (m >> C) & b;". */
-static rtx
-noce_get_condition (jump, earliest)
- rtx jump;
- rtx *earliest;
+static int
+noce_try_sign_mask (struct noce_if_info *if_info)
{
- rtx cond;
- rtx set;
+ rtx cond, t, m, c, seq;
+ enum machine_mode mode;
+ enum rtx_code code;
+
+ if (no_new_pseudos)
+ return FALSE;
+
+ cond = if_info->cond;
+ code = GET_CODE (cond);
+ m = XEXP (cond, 0);
+ c = XEXP (cond, 1);
- /* If the condition variable is a register and is MODE_INT, accept it.
- Otherwise, fall back on get_condition. */
+ t = NULL_RTX;
+ if (if_info->a == const0_rtx)
+ {
+ if ((code == LT && c == const0_rtx)
+ || (code == LE && c == constm1_rtx))
+ t = if_info->b;
+ }
+ else if (if_info->b == const0_rtx)
+ {
+ if ((code == GE && c == const0_rtx)
+ || (code == GT && c == constm1_rtx))
+ t = if_info->a;
+ }
+
+ if (! t || side_effects_p (t))
+ return FALSE;
+
+ /* We currently don't handle different modes. */
+ mode = GET_MODE (t);
+ if (GET_MODE (m) != mode)
+ return FALSE;
+
+ /* This is only profitable if T is cheap, or T is unconditionally
+ executed/evaluated in the original insn sequence. */
+ if (rtx_cost (t, SET) >= COSTS_N_INSNS (2)
+ && (!if_info->b_unconditional
+ || t != if_info->b))
+ return FALSE;
+
+ start_sequence ();
+ /* Use emit_store_flag to generate "m < 0 ? -1 : 0" instead of expanding
+ "(signed) m >> 31" directly. This benefits targets with specialized
+ insns to obtain the signmask, but still uses ashr_optab otherwise. */
+ m = emit_store_flag (gen_reg_rtx (mode), LT, m, const0_rtx, mode, 0, -1);
+ t = m ? expand_binop (mode, and_optab, m, t, NULL_RTX, 0, OPTAB_DIRECT)
+ : NULL_RTX;
+
+ if (!t)
+ {
+ end_sequence ();
+ return FALSE;
+ }
+
+ noce_emit_move_insn (if_info->x, t);
+
+ seq = end_ifcvt_sequence (if_info);
+ if (!seq)
+ return FALSE;
+
+ emit_insn_before_setloc (seq, if_info->jump, INSN_LOCATOR (if_info->insn_a));
+ return TRUE;
+}
+
+
+/* Similar to get_condition, only the resulting condition must be
+ valid at JUMP, instead of at EARLIEST. */
+
+static rtx
+noce_get_condition (rtx jump, rtx *earliest)
+{
+ rtx cond, set, tmp;
+ bool reverse;
if (! any_condjump_p (jump))
return NULL_RTX;
set = pc_set (jump);
+ /* If this branches to JUMP_LABEL when the condition is false,
+ reverse the condition. */
+ reverse = (GET_CODE (XEXP (SET_SRC (set), 2)) == LABEL_REF
+ && XEXP (XEXP (SET_SRC (set), 2), 0) == JUMP_LABEL (jump));
+
+ /* If the condition variable is a register and is MODE_INT, accept it. */
+
cond = XEXP (SET_SRC (set), 0);
- if (GET_CODE (XEXP (cond, 0)) == REG
- && GET_MODE_CLASS (GET_MODE (XEXP (cond, 0))) == MODE_INT)
+ tmp = XEXP (cond, 0);
+ if (REG_P (tmp) && GET_MODE_CLASS (GET_MODE (tmp)) == MODE_INT)
{
*earliest = jump;
- /* If this branches to JUMP_LABEL when the condition is false,
- reverse the condition. */
- if (GET_CODE (XEXP (SET_SRC (set), 2)) == LABEL_REF
- && XEXP (XEXP (SET_SRC (set), 2), 0) == JUMP_LABEL (jump))
+ if (reverse)
cond = gen_rtx_fmt_ee (reverse_condition (GET_CODE (cond)),
- GET_MODE (cond), XEXP (cond, 0),
- XEXP (cond, 1));
+ GET_MODE (cond), tmp, XEXP (cond, 1));
+ return cond;
}
- else
- cond = get_condition (jump, earliest);
- return cond;
+ /* Otherwise, fall back on canonicalize_condition to do the dirty
+ work of manipulating MODE_CC values and COMPARE rtx codes. */
+ return canonicalize_condition (jump, cond, reverse, earliest,
+ NULL_RTX, false, true);
}
/* Return true if OP is ok for if-then-else processing. */
static int
-noce_operand_ok (op)
- rtx op;
+noce_operand_ok (rtx op)
{
/* We special-case memories, so handle any of them with
no address side effects. */
- if (GET_CODE (op) == MEM)
+ if (MEM_P (op))
return ! side_effects_p (XEXP (op, 0));
if (side_effects_p (op))
/* Given a simple IF-THEN or IF-THEN-ELSE block, attempt to convert it
without using conditional execution. Return TRUE if we were
- successful at converting the the block. */
+ successful at converting the block. */
static int
-noce_process_if_block (test_bb, then_bb, else_bb, join_bb)
- basic_block test_bb; /* Basic block test is in */
- basic_block then_bb; /* Basic block for THEN block */
- basic_block else_bb; /* Basic block for ELSE block */
- basic_block join_bb; /* Basic block the join label is in */
+noce_process_if_block (struct ce_if_block * ce_info)
{
+ basic_block test_bb = ce_info->test_bb; /* test block */
+ basic_block then_bb = ce_info->then_bb; /* THEN */
+ basic_block else_bb = ce_info->else_bb; /* ELSE or NULL */
+ struct noce_if_info if_info;
+ rtx insn_a, insn_b;
+ rtx set_a, set_b;
+ rtx orig_x, x, a, b;
+ rtx jump, cond;
+
/* We're looking for patterns of the form
(1) if (...) x = a; else x = b;
??? For future expansion, look for multiple X in such patterns. */
- struct noce_if_info if_info;
- rtx insn_a, insn_b;
- rtx set_a, set_b;
- rtx orig_x, x, a, b;
- rtx jump, cond, insn;
+ /* If test is comprised of && or || elements, don't handle it unless it is
+ the special case of && elements without an ELSE block. */
+ if (ce_info->num_multiple_test_blocks)
+ {
+ if (else_bb || ! ce_info->and_and_p)
+ return FALSE;
+
+ ce_info->test_bb = test_bb = ce_info->last_test_bb;
+ ce_info->num_multiple_test_blocks = 0;
+ ce_info->num_and_and_blocks = 0;
+ ce_info->num_or_or_blocks = 0;
+ }
/* If this is not a standard conditional jump, we can't parse it. */
- jump = test_bb->end;
+ jump = BB_END (test_bb);
cond = noce_get_condition (jump, &if_info.cond_earliest);
if (! cond)
return FALSE;
- /* If the conditional jump is more than just a conditional jump,
- then we can not do if-conversion on this block. */
+ /* If the conditional jump is more than just a conditional
+ jump, then we can not do if-conversion on this block. */
if (! onlyjump_p (jump))
return FALSE;
/* Look for one of the potential sets. */
insn_a = first_active_insn (then_bb);
if (! insn_a
- || ! last_active_insn_p (then_bb, insn_a)
+ || insn_a != last_active_insn (then_bb, FALSE)
|| (set_a = single_set (insn_a)) == NULL_RTX)
return FALSE;
{
insn_b = first_active_insn (else_bb);
if (! insn_b
- || ! last_active_insn_p (else_bb, insn_b)
+ || insn_b != last_active_insn (else_bb, FALSE)
|| (set_b = single_set (insn_b)) == NULL_RTX
|| ! rtx_equal_p (x, SET_DEST (set_b)))
return FALSE;
else
{
insn_b = prev_nonnote_insn (if_info.cond_earliest);
+ /* We're going to be moving the evaluation of B down from above
+ COND_EARLIEST to JUMP. Make sure the relevant data is still
+ intact. */
if (! insn_b
- || GET_CODE (insn_b) != INSN
+ || !NONJUMP_INSN_P (insn_b)
|| (set_b = single_set (insn_b)) == NULL_RTX
|| ! rtx_equal_p (x, SET_DEST (set_b))
- || reg_mentioned_p (x, cond)
- || reg_mentioned_p (x, a)
- || reg_mentioned_p (x, SET_SRC (set_b)))
+ || reg_overlap_mentioned_p (x, SET_SRC (set_b))
+ || modified_between_p (SET_SRC (set_b),
+ PREV_INSN (if_info.cond_earliest), jump)
+ /* Likewise with X. In particular this can happen when
+ noce_get_condition looks farther back in the instruction
+ stream than one might expect. */
+ || reg_overlap_mentioned_p (x, cond)
+ || reg_overlap_mentioned_p (x, a)
+ || modified_between_p (x, PREV_INSN (if_info.cond_earliest), jump))
insn_b = set_b = NULL_RTX;
}
- b = (set_b ? SET_SRC (set_b) : x);
- /* X may not be mentioned in the range (cond_earliest, jump]. */
- for (insn = jump; insn != if_info.cond_earliest; insn = PREV_INSN (insn))
- if (INSN_P (insn) && reg_mentioned_p (x, insn))
- return FALSE;
+ /* If x has side effects then only the if-then-else form is safe to
+ convert. But even in that case we would need to restore any notes
+ (such as REG_INC) at then end. That can be tricky if
+ noce_emit_move_insn expands to more than one insn, so disable the
+ optimization entirely for now if there are side effects. */
+ if (side_effects_p (x))
+ return FALSE;
- /* A and B may not be modified in the range [cond_earliest, jump). */
- for (insn = if_info.cond_earliest; insn != jump; insn = NEXT_INSN (insn))
- if (INSN_P (insn)
- && (modified_in_p (a, insn) || modified_in_p (b, insn)))
- return FALSE;
+ b = (set_b ? SET_SRC (set_b) : x);
/* Only operate on register destinations, and even then avoid extending
the lifetime of hard registers on small register class machines. */
orig_x = x;
- if (GET_CODE (x) != REG
+ if (!REG_P (x)
|| (SMALL_REGISTER_CLASSES
&& REGNO (x) < FIRST_PSEUDO_REGISTER))
{
- if (no_new_pseudos)
+ if (no_new_pseudos || GET_MODE (x) == BLKmode)
return FALSE;
x = gen_reg_rtx (GET_MODE (GET_CODE (x) == STRICT_LOW_PART
? XEXP (x, 0) : x));
if_info.x = x;
if_info.a = a;
if_info.b = b;
+ if_info.b_unconditional = else_bb == 0;
/* Try optimizations in some approximation of a useful order. */
/* ??? Should first look to see if X is live incoming at all. If it
{
rtx note;
- if (else_bb && insn_b == else_bb->end)
- else_bb->end = PREV_INSN (insn_b);
- reorder_insns (insn_b, insn_b, PREV_INSN (if_info.cond_earliest));
+ if (else_bb && insn_b == BB_END (else_bb))
+ BB_END (else_bb) = PREV_INSN (insn_b);
+ reorder_insns (insn_b, insn_b, PREV_INSN (jump));
/* If there was a REG_EQUAL note, delete it since it may have been
true due to this insn being after a jump. */
x must be executed twice. */
else if (insn_b && side_effects_p (orig_x))
return FALSE;
-
+
x = orig_x;
goto success;
}
+ /* Disallow the "if (...) x = a;" form (with an implicit "else x = x;")
+ for most optimizations if writing to x may trap, i.e. it's a memory
+ other than a static var or a stack slot. */
+ if (! set_b
+ && MEM_P (orig_x)
+ && ! MEM_NOTRAP_P (orig_x)
+ && rtx_addr_can_trap_p (XEXP (orig_x, 0)))
+ {
+ if (HAVE_conditional_move)
+ {
+ if (noce_try_cmove (&if_info))
+ goto success;
+ if (! HAVE_conditional_execution
+ && noce_try_cmove_arith (&if_info))
+ goto success;
+ }
+ return FALSE;
+ }
+
+ if (noce_try_move (&if_info))
+ goto success;
if (noce_try_store_flag (&if_info))
goto success;
if (noce_try_minmax (&if_info))
{
if (noce_try_store_flag_constants (&if_info))
goto success;
- if (noce_try_store_flag_inc (&if_info))
+ if (noce_try_addcc (&if_info))
goto success;
if (noce_try_store_flag_mask (&if_info))
goto success;
if (HAVE_conditional_move
&& noce_try_cmove_arith (&if_info))
goto success;
+ if (noce_try_sign_mask (&if_info))
+ goto success;
}
return FALSE;
if (insn_b && else_bb)
delete_insn (insn_b);
- /* The new insns will have been inserted before cond_earliest. We should
- be able to remove the jump with impunity, but the condition itself may
- have been modified by gcse to be shared across basic blocks. */
+ /* The new insns will have been inserted immediately before the jump. We
+ should be able to remove the jump with impunity, but the condition itself
+ may have been modified by gcse to be shared across basic blocks. */
delete_insn (jump);
/* If we used a temporary, fix it up now. */
if (orig_x != x)
{
start_sequence ();
- noce_emit_move_insn (copy_rtx (orig_x), x);
- insn_b = gen_sequence ();
+ noce_emit_move_insn (orig_x, x);
+ insn_b = get_insns ();
+ set_used_flags (orig_x);
+ unshare_all_rtl_in_chain (insn_b);
end_sequence ();
- emit_insn_after (insn_b, test_bb->end);
+ emit_insn_after_setloc (insn_b, BB_END (test_bb), INSN_LOCATOR (insn_a));
}
/* Merge the blocks! */
- merge_if_block (test_bb, then_bb, else_bb, join_bb);
+ merge_if_block (ce_info);
return TRUE;
}
straight line code. Return true if successful. */
static int
-process_if_block (test_bb, then_bb, else_bb, join_bb)
- basic_block test_bb; /* Basic block test is in */
- basic_block then_bb; /* Basic block for THEN block */
- basic_block else_bb; /* Basic block for ELSE block */
- basic_block join_bb; /* Basic block the join label is in */
+process_if_block (struct ce_if_block * ce_info)
{
if (! reload_completed
- && noce_process_if_block (test_bb, then_bb, else_bb, join_bb))
+ && noce_process_if_block (ce_info))
return TRUE;
- if (HAVE_conditional_execution
- && reload_completed
- && cond_exec_process_if_block (test_bb, then_bb, else_bb, join_bb))
- return TRUE;
+ if (HAVE_conditional_execution && reload_completed)
+ {
+ /* If we have && and || tests, try to first handle combining the && and
+ || tests into the conditional code, and if that fails, go back and
+ handle it without the && and ||, which at present handles the && case
+ if there was no ELSE block. */
+ if (cond_exec_process_if_block (ce_info, TRUE))
+ return TRUE;
+
+ if (ce_info->num_multiple_test_blocks)
+ {
+ cancel_changes (0);
+
+ if (cond_exec_process_if_block (ce_info, FALSE))
+ return TRUE;
+ }
+ }
return FALSE;
}
/* Merge the blocks and mark for local life update. */
static void
-merge_if_block (test_bb, then_bb, else_bb, join_bb)
- basic_block test_bb; /* Basic block test is in */
- basic_block then_bb; /* Basic block for THEN block */
- basic_block else_bb; /* Basic block for ELSE block */
- basic_block join_bb; /* Basic block the join label is in */
+merge_if_block (struct ce_if_block * ce_info)
{
+ basic_block test_bb = ce_info->test_bb; /* last test block */
+ basic_block then_bb = ce_info->then_bb; /* THEN */
+ basic_block else_bb = ce_info->else_bb; /* ELSE or NULL */
+ basic_block join_bb = ce_info->join_bb; /* join block */
basic_block combo_bb;
/* All block merging is done into the lower block numbers. */
combo_bb = test_bb;
- /* First merge TEST block into THEN block. This is a no-brainer since
- the THEN block did not have a code label to begin with. */
+ /* Merge any basic blocks to handle && and || subtests. Each of
+ the blocks are on the fallthru path from the predecessor block. */
+ if (ce_info->num_multiple_test_blocks > 0)
+ {
+ basic_block bb = test_bb;
+ basic_block last_test_bb = ce_info->last_test_bb;
+ basic_block fallthru = block_fallthru (bb);
- if (combo_bb->global_live_at_end)
- COPY_REG_SET (combo_bb->global_live_at_end, then_bb->global_live_at_end);
- merge_blocks_nomove (combo_bb, then_bb);
- num_removed_blocks++;
+ do
+ {
+ bb = fallthru;
+ fallthru = block_fallthru (bb);
+ merge_blocks (combo_bb, bb);
+ num_true_changes++;
+ }
+ while (bb != last_test_bb);
+ }
+
+ /* Merge TEST block into THEN block. Normally the THEN block won't have a
+ label, but it might if there were || tests. That label's count should be
+ zero, and it normally should be removed. */
+
+ if (then_bb)
+ {
+ if (combo_bb->global_live_at_end)
+ COPY_REG_SET (combo_bb->global_live_at_end,
+ then_bb->global_live_at_end);
+ merge_blocks (combo_bb, then_bb);
+ num_true_changes++;
+ }
/* The ELSE block, if it existed, had a label. That label count
will almost always be zero, but odd things can happen when labels
get their addresses taken. */
if (else_bb)
{
- merge_blocks_nomove (combo_bb, else_bb);
- num_removed_blocks++;
+ merge_blocks (combo_bb, else_bb);
+ num_true_changes++;
}
/* If there was no join block reported, that means it was not adjacent
if (! join_bb)
{
+ rtx last = BB_END (combo_bb);
+
/* The outgoing edge for the current COMBO block should already
be correct. Verify this. */
- if (combo_bb->succ == NULL_EDGE)
- abort ();
+ if (EDGE_COUNT (combo_bb->succs) == 0)
+ {
+ if (find_reg_note (last, REG_NORETURN, NULL))
+ ;
+ else if (NONJUMP_INSN_P (last)
+ && GET_CODE (PATTERN (last)) == TRAP_IF
+ && TRAP_CONDITION (PATTERN (last)) == const_true_rtx)
+ ;
+ else
+ abort ();
+ }
- /* There should still be a branch at the end of the THEN or ELSE
+ /* There should still be something at the end of the THEN or ELSE
blocks taking us to our final destination. */
- if (GET_CODE (combo_bb->end) != JUMP_INSN)
+ else if (JUMP_P (last))
+ ;
+ else if (EDGE_SUCC (combo_bb, 0)->dest == EXIT_BLOCK_PTR
+ && CALL_P (last)
+ && SIBLING_CALL_P (last))
+ ;
+ else if ((EDGE_SUCC (combo_bb, 0)->flags & EDGE_EH)
+ && can_throw_internal (last))
+ ;
+ else
abort ();
}
Since we've already merged the TEST, THEN and ELSE blocks, we should
have only one remaining edge from our if-then-else diamond. If there
is more than one remaining edge, it must come from elsewhere. There
- may be zero incoming edges if the THEN block didn't actually join
+ may be zero incoming edges if the THEN block didn't actually join
back up (as with a call to abort). */
- else if ((join_bb->pred == NULL
- || join_bb->pred->pred_next == NULL)
+ else if (EDGE_COUNT (join_bb->preds) < 2
&& join_bb != EXIT_BLOCK_PTR)
{
/* We can merge the JOIN. */
if (combo_bb->global_live_at_end)
COPY_REG_SET (combo_bb->global_live_at_end,
join_bb->global_live_at_end);
- merge_blocks_nomove (combo_bb, join_bb);
- num_removed_blocks++;
+
+ merge_blocks (combo_bb, join_bb);
+ num_true_changes++;
}
else
{
/* The outgoing edge for the current COMBO block should already
be correct. Verify this. */
- if (combo_bb->succ->succ_next != NULL_EDGE
- || combo_bb->succ->dest != join_bb)
+ if (EDGE_COUNT (combo_bb->succs) > 1
+ || EDGE_SUCC (combo_bb, 0)->dest != join_bb)
abort ();
/* Remove the jump and cruft from the end of the COMBO block. */
if (join_bb != EXIT_BLOCK_PTR)
- tidy_fallthru_edge (combo_bb->succ, combo_bb, join_bb);
+ tidy_fallthru_edge (EDGE_SUCC (combo_bb, 0));
}
num_updated_if_blocks++;
}
\f
-/* Find a block ending in a simple IF condition. Return TRUE if
- we were able to transform it in some way. */
+/* Find a block ending in a simple IF condition and try to transform it
+ in some way. When converting a multi-block condition, put the new code
+ in the first such block and delete the rest. Return a pointer to this
+ first block if some transformation was done. Return NULL otherwise. */
-static int
-find_if_header (test_bb)
- basic_block test_bb;
+static basic_block
+find_if_header (basic_block test_bb, int pass)
{
+ ce_if_block_t ce_info;
edge then_edge;
edge else_edge;
/* The kind of block we're looking for has exactly two successors. */
- if ((then_edge = test_bb->succ) == NULL_EDGE
- || (else_edge = then_edge->succ_next) == NULL_EDGE
- || else_edge->succ_next != NULL_EDGE)
- return FALSE;
+ if (EDGE_COUNT (test_bb->succs) != 2)
+ return NULL;
+
+ then_edge = EDGE_SUCC (test_bb, 0);
+ else_edge = EDGE_SUCC (test_bb, 1);
/* Neither edge should be abnormal. */
if ((then_edge->flags & EDGE_COMPLEX)
|| (else_edge->flags & EDGE_COMPLEX))
- return FALSE;
+ return NULL;
+
+ /* Nor exit the loop. */
+ if ((then_edge->flags & EDGE_LOOP_EXIT)
+ || (else_edge->flags & EDGE_LOOP_EXIT))
+ return NULL;
/* The THEN edge is canonically the one that falls through. */
if (then_edge->flags & EDGE_FALLTHRU)
}
else
/* Otherwise this must be a multiway branch of some sort. */
- return FALSE;
+ return NULL;
- if (find_if_block (test_bb, then_edge, else_edge))
+ memset (&ce_info, '\0', sizeof (ce_info));
+ ce_info.test_bb = test_bb;
+ ce_info.then_bb = then_edge->dest;
+ ce_info.else_bb = else_edge->dest;
+ ce_info.pass = pass;
+
+#ifdef IFCVT_INIT_EXTRA_FIELDS
+ IFCVT_INIT_EXTRA_FIELDS (&ce_info);
+#endif
+
+ if (find_if_block (&ce_info))
goto success;
+
if (HAVE_trap && HAVE_conditional_trap
&& find_cond_trap (test_bb, then_edge, else_edge))
goto success;
- if (post_dominators
+
+ if (dom_computed[CDI_POST_DOMINATORS] >= DOM_NO_FAST_QUERY
&& (! HAVE_conditional_execution || reload_completed))
{
if (find_if_case_1 (test_bb, then_edge, else_edge))
goto success;
}
- return FALSE;
+ return NULL;
success:
- if (rtl_dump_file)
- fprintf (rtl_dump_file, "Conversion succeeded.\n");
- return TRUE;
+ if (dump_file)
+ fprintf (dump_file, "Conversion succeeded on pass %d.\n", pass);
+ return ce_info.test_bb;
+}
+
+/* Return true if a block has two edges, one of which falls through to the next
+ block, and the other jumps to a specific block, so that we can tell if the
+ block is part of an && test or an || test. Returns either -1 or the number
+ of non-note, non-jump, non-USE/CLOBBER insns in the block. */
+
+static int
+block_jumps_and_fallthru_p (basic_block cur_bb, basic_block target_bb)
+{
+ edge cur_edge;
+ int fallthru_p = FALSE;
+ int jump_p = FALSE;
+ rtx insn;
+ rtx end;
+ int n_insns = 0;
+ edge_iterator ei;
+
+ if (!cur_bb || !target_bb)
+ return -1;
+
+ /* If no edges, obviously it doesn't jump or fallthru. */
+ if (EDGE_COUNT (cur_bb->succs) == 0)
+ return FALSE;
+
+ FOR_EACH_EDGE (cur_edge, ei, cur_bb->succs)
+ {
+ if (cur_edge->flags & EDGE_COMPLEX)
+ /* Anything complex isn't what we want. */
+ return -1;
+
+ else if (cur_edge->flags & EDGE_FALLTHRU)
+ fallthru_p = TRUE;
+
+ else if (cur_edge->dest == target_bb)
+ jump_p = TRUE;
+
+ else
+ return -1;
+ }
+
+ if ((jump_p & fallthru_p) == 0)
+ return -1;
+
+ /* Don't allow calls in the block, since this is used to group && and ||
+ together for conditional execution support. ??? we should support
+ conditional execution support across calls for IA-64 some day, but
+ for now it makes the code simpler. */
+ end = BB_END (cur_bb);
+ insn = BB_HEAD (cur_bb);
+
+ while (insn != NULL_RTX)
+ {
+ if (CALL_P (insn))
+ return -1;
+
+ if (INSN_P (insn)
+ && !JUMP_P (insn)
+ && GET_CODE (PATTERN (insn)) != USE
+ && GET_CODE (PATTERN (insn)) != CLOBBER)
+ n_insns++;
+
+ if (insn == end)
+ break;
+
+ insn = NEXT_INSN (insn);
+ }
+
+ return n_insns;
}
/* Determine if a given basic block heads a simple IF-THEN or IF-THEN-ELSE
block. If so, we'll try to convert the insns to not require the branch.
- Return TRUE if we were successful at converting the the block. */
+ Return TRUE if we were successful at converting the block. */
static int
-find_if_block (test_bb, then_edge, else_edge)
- basic_block test_bb;
- edge then_edge, else_edge;
+find_if_block (struct ce_if_block * ce_info)
{
- basic_block then_bb = then_edge->dest;
- basic_block else_bb = else_edge->dest;
+ basic_block test_bb = ce_info->test_bb;
+ basic_block then_bb = ce_info->then_bb;
+ basic_block else_bb = ce_info->else_bb;
basic_block join_bb = NULL_BLOCK;
- edge then_succ = then_bb->succ;
- edge else_succ = else_bb->succ;
- int next_index;
+ edge cur_edge;
+ basic_block next;
+ edge_iterator ei;
+
+ ce_info->last_test_bb = test_bb;
+
+ /* Discover if any fall through predecessors of the current test basic block
+ were && tests (which jump to the else block) or || tests (which jump to
+ the then block). */
+ if (HAVE_conditional_execution && reload_completed
+ && EDGE_COUNT (test_bb->preds) == 1
+ && EDGE_PRED (test_bb, 0)->flags == EDGE_FALLTHRU)
+ {
+ basic_block bb = EDGE_PRED (test_bb, 0)->src;
+ basic_block target_bb;
+ int max_insns = MAX_CONDITIONAL_EXECUTE;
+ int n_insns;
+
+ /* Determine if the preceding block is an && or || block. */
+ if ((n_insns = block_jumps_and_fallthru_p (bb, else_bb)) >= 0)
+ {
+ ce_info->and_and_p = TRUE;
+ target_bb = else_bb;
+ }
+ else if ((n_insns = block_jumps_and_fallthru_p (bb, then_bb)) >= 0)
+ {
+ ce_info->and_and_p = FALSE;
+ target_bb = then_bb;
+ }
+ else
+ target_bb = NULL_BLOCK;
+
+ if (target_bb && n_insns <= max_insns)
+ {
+ int total_insns = 0;
+ int blocks = 0;
+
+ ce_info->last_test_bb = test_bb;
+
+ /* Found at least one && or || block, look for more. */
+ do
+ {
+ ce_info->test_bb = test_bb = bb;
+ total_insns += n_insns;
+ blocks++;
+
+ if (EDGE_COUNT (bb->preds) != 1)
+ break;
- /* The THEN block of an IF-THEN combo must have exactly one predecessor. */
- if (then_bb->pred->pred_next != NULL_EDGE)
+ bb = EDGE_PRED (bb, 0)->src;
+ n_insns = block_jumps_and_fallthru_p (bb, target_bb);
+ }
+ while (n_insns >= 0 && (total_insns + n_insns) <= max_insns);
+
+ ce_info->num_multiple_test_blocks = blocks;
+ ce_info->num_multiple_test_insns = total_insns;
+
+ if (ce_info->and_and_p)
+ ce_info->num_and_and_blocks = blocks;
+ else
+ ce_info->num_or_or_blocks = blocks;
+ }
+ }
+
+ /* The THEN block of an IF-THEN combo must have exactly one predecessor,
+ other than any || blocks which jump to the THEN block. */
+ if ((EDGE_COUNT (then_bb->preds) - ce_info->num_or_or_blocks) != 1)
return FALSE;
+
+ /* The edges of the THEN and ELSE blocks cannot have complex edges. */
+ FOR_EACH_EDGE (cur_edge, ei, then_bb->preds)
+ {
+ if (cur_edge->flags & EDGE_COMPLEX)
+ return FALSE;
+ }
+
+ FOR_EACH_EDGE (cur_edge, ei, else_bb->preds)
+ {
+ if (cur_edge->flags & EDGE_COMPLEX)
+ return FALSE;
+ }
/* The THEN block of an IF-THEN combo must have zero or one successors. */
- if (then_succ != NULL_EDGE
- && (then_succ->succ_next != NULL_EDGE
- || (then_succ->flags & EDGE_COMPLEX)))
+ if (EDGE_COUNT (then_bb->succs) > 0
+ && (EDGE_COUNT (then_bb->succs) > 1
+ || (EDGE_SUCC (then_bb, 0)->flags & EDGE_COMPLEX)
+ || (flow2_completed && tablejump_p (BB_END (then_bb), NULL, NULL))))
return FALSE;
/* If the THEN block has no successors, conditional execution can still
only one incoming edge -- the CFG manipulation is too ugly otherwise.
Check for the last insn of the THEN block being an indirect jump, which
is listed as not having any successors, but confuses the rest of the CE
- code processing. XXX we should fix this in the future. */
- if (then_succ == NULL)
+ code processing. ??? we should fix this in the future. */
+ if (EDGE_COUNT (then_bb->succs) == 0)
{
- if (else_bb->pred->pred_next == NULL_EDGE)
+ if (EDGE_COUNT (else_bb->preds) == 1)
{
- rtx last_insn = then_bb->end;
+ rtx last_insn = BB_END (then_bb);
while (last_insn
- && GET_CODE (last_insn) == NOTE
- && last_insn != then_bb->head)
+ && NOTE_P (last_insn)
+ && last_insn != BB_HEAD (then_bb))
last_insn = PREV_INSN (last_insn);
if (last_insn
- && GET_CODE (last_insn) == JUMP_INSN
+ && JUMP_P (last_insn)
&& ! simplejump_p (last_insn))
return FALSE;
/* If the THEN block's successor is the other edge out of the TEST block,
then we have an IF-THEN combo without an ELSE. */
- else if (then_succ->dest == else_bb)
+ else if (EDGE_SUCC (then_bb, 0)->dest == else_bb)
{
join_bb = else_bb;
else_bb = NULL_BLOCK;
/* If the THEN and ELSE block meet in a subsequent block, and the ELSE
has exactly one predecessor and one successor, and the outgoing edge
is not complex, then we have an IF-THEN-ELSE combo. */
- else if (else_succ != NULL_EDGE
- && then_succ->dest == else_succ->dest
- && else_bb->pred->pred_next == NULL_EDGE
- && else_succ->succ_next == NULL_EDGE
- && ! (else_succ->flags & EDGE_COMPLEX))
- join_bb = else_succ->dest;
+ else if (EDGE_COUNT (else_bb->succs) == 1
+ && EDGE_SUCC (then_bb, 0)->dest == EDGE_SUCC (else_bb, 0)->dest
+ && EDGE_COUNT (else_bb->preds) == 1
+ && ! (EDGE_SUCC (else_bb, 0)->flags & EDGE_COMPLEX)
+ && ! (flow2_completed && tablejump_p (BB_END (else_bb), NULL, NULL)))
+ join_bb = EDGE_SUCC (else_bb, 0)->dest;
/* Otherwise it is not an IF-THEN or IF-THEN-ELSE combination. */
else
- return FALSE;
+ return FALSE;
num_possible_if_blocks++;
- if (rtl_dump_file)
+ if (dump_file)
{
- if (else_bb)
- fprintf (rtl_dump_file,
- "\nIF-THEN-ELSE block found, start %d, then %d, else %d, join %d\n",
- test_bb->index, then_bb->index, else_bb->index,
- join_bb->index);
- else
- fprintf (rtl_dump_file,
- "\nIF-THEN block found, start %d, then %d, join %d\n",
- test_bb->index, then_bb->index, join_bb->index);
- }
+ fprintf (dump_file,
+ "\nIF-THEN%s block found, pass %d, start block %d "
+ "[insn %d], then %d [%d]",
+ (else_bb) ? "-ELSE" : "",
+ ce_info->pass,
+ test_bb->index,
+ BB_HEAD (test_bb) ? (int)INSN_UID (BB_HEAD (test_bb)) : -1,
+ then_bb->index,
+ BB_HEAD (then_bb) ? (int)INSN_UID (BB_HEAD (then_bb)) : -1);
- /* Make sure IF, THEN, and ELSE, blocks are adjacent. Actually, we
- get the first condition for free, since we've already asserted that
- there's a fallthru edge from IF to THEN. */
+ if (else_bb)
+ fprintf (dump_file, ", else %d [%d]",
+ else_bb->index,
+ BB_HEAD (else_bb) ? (int)INSN_UID (BB_HEAD (else_bb)) : -1);
+
+ fprintf (dump_file, ", join %d [%d]",
+ join_bb->index,
+ BB_HEAD (join_bb) ? (int)INSN_UID (BB_HEAD (join_bb)) : -1);
+
+ if (ce_info->num_multiple_test_blocks > 0)
+ fprintf (dump_file, ", %d %s block%s last test %d [%d]",
+ ce_info->num_multiple_test_blocks,
+ (ce_info->and_and_p) ? "&&" : "||",
+ (ce_info->num_multiple_test_blocks == 1) ? "" : "s",
+ ce_info->last_test_bb->index,
+ ((BB_HEAD (ce_info->last_test_bb))
+ ? (int)INSN_UID (BB_HEAD (ce_info->last_test_bb))
+ : -1));
+
+ fputc ('\n', dump_file);
+ }
+
+ /* Make sure IF, THEN, and ELSE, blocks are adjacent. Actually, we get the
+ first condition for free, since we've already asserted that there's a
+ fallthru edge from IF to THEN. Likewise for the && and || blocks, since
+ we checked the FALLTHRU flag, those are already adjacent to the last IF
+ block. */
/* ??? As an enhancement, move the ELSE block. Have to deal with
BLOCK notes, if by no other means than aborting the merge if they
exist. Sticky enough I don't want to think about it now. */
- next_index = then_bb->index;
- if (else_bb && ++next_index != else_bb->index)
+ next = then_bb;
+ if (else_bb && (next = next->next_bb) != else_bb)
return FALSE;
- if (++next_index != join_bb->index && join_bb->index != EXIT_BLOCK)
+ if ((next = next->next_bb) != join_bb && join_bb != EXIT_BLOCK_PTR)
{
if (else_bb)
join_bb = NULL;
}
/* Do the real work. */
- return process_if_block (test_bb, then_bb, else_bb, join_bb);
+ ce_info->else_bb = else_bb;
+ ce_info->join_bb = join_bb;
+
+ return process_if_block (ce_info);
}
-/* Convert a branch over a trap, or a branch to a trap,
- into a conditional trap. */
+/* Convert a branch over a trap, or a branch
+ to a trap, into a conditional trap. */
static int
-find_cond_trap (test_bb, then_edge, else_edge)
- basic_block test_bb;
- edge then_edge, else_edge;
+find_cond_trap (basic_block test_bb, edge then_edge, edge else_edge)
{
- basic_block then_bb, else_bb, join_bb, trap_bb;
+ basic_block then_bb = then_edge->dest;
+ basic_block else_bb = else_edge->dest;
+ basic_block other_bb, trap_bb;
rtx trap, jump, cond, cond_earliest, seq;
enum rtx_code code;
- then_bb = then_edge->dest;
- else_bb = else_edge->dest;
- join_bb = NULL;
-
/* Locate the block with the trap instruction. */
/* ??? While we look for no successors, we really ought to allow
EH successors. Need to fix merge_if_block for that to work. */
- /* ??? We can't currently handle merging the blocks if they are not
- already adjacent. Prevent losage in merge_if_block by detecting
- this now. */
- if (then_bb->succ == NULL)
- {
- trap_bb = then_bb;
- if (else_bb->index != then_bb->index + 1)
- return FALSE;
- join_bb = else_bb;
- else_bb = NULL;
- }
- else if (else_bb->succ == NULL)
- {
- trap_bb = else_bb;
- if (else_bb->index != then_bb->index + 1)
- else_bb = NULL;
- else if (then_bb->succ
- && ! then_bb->succ->succ_next
- && ! (then_bb->succ->flags & EDGE_COMPLEX)
- && then_bb->succ->dest->index == else_bb->index + 1)
- join_bb = then_bb->succ->dest;
- }
+ if ((trap = block_has_only_trap (then_bb)) != NULL)
+ trap_bb = then_bb, other_bb = else_bb;
+ else if ((trap = block_has_only_trap (else_bb)) != NULL)
+ trap_bb = else_bb, other_bb = then_bb;
else
return FALSE;
- /* Don't confuse a conditional return with something we want to
- optimize here. */
- if (trap_bb == EXIT_BLOCK_PTR)
- return FALSE;
-
- /* The only instruction in the THEN block must be the trap. */
- trap = first_active_insn (trap_bb);
- if (! (trap == trap_bb->end
- && GET_CODE (PATTERN (trap)) == TRAP_IF
- && TRAP_CONDITION (PATTERN (trap)) == const_true_rtx))
- return FALSE;
-
- if (rtl_dump_file)
+ if (dump_file)
{
- if (trap_bb == then_bb)
- fprintf (rtl_dump_file,
- "\nTRAP-IF block found, start %d, trap %d",
- test_bb->index, then_bb->index);
- else
- fprintf (rtl_dump_file,
- "\nTRAP-IF block found, start %d, then %d, trap %d",
- test_bb->index, then_bb->index, trap_bb->index);
- if (join_bb)
- fprintf (rtl_dump_file, ", join %d\n", join_bb->index);
- else
- fputc ('\n', rtl_dump_file);
+ fprintf (dump_file, "\nTRAP-IF block found, start %d, trap %d\n",
+ test_bb->index, trap_bb->index);
}
/* If this is not a standard conditional jump, we can't parse it. */
- jump = test_bb->end;
+ jump = BB_END (test_bb);
cond = noce_get_condition (jump, &cond_earliest);
if (! cond)
return FALSE;
- /* If the conditional jump is more than just a conditional jump,
- then we can not do if-conversion on this block. */
+ /* If the conditional jump is more than just a conditional jump, then
+ we can not do if-conversion on this block. */
if (! onlyjump_p (jump))
return FALSE;
}
/* Attempt to generate the conditional trap. */
- seq = gen_cond_trap (code, XEXP (cond, 0), XEXP (cond, 1),
+ seq = gen_cond_trap (code, XEXP (cond, 0),
+ XEXP (cond, 1),
TRAP_CODE (PATTERN (trap)));
if (seq == NULL)
return FALSE;
- /* Emit the new insns before cond_earliest; delete the old jump
- and trap insns. */
+ num_true_changes++;
- emit_insn_before (seq, cond_earliest);
+ /* Emit the new insns before cond_earliest. */
+ emit_insn_before_setloc (seq, cond_earliest, INSN_LOCATOR (trap));
- delete_insn (jump);
+ /* Delete the trap block if possible. */
+ remove_edge (trap_bb == then_bb ? then_edge : else_edge);
+ if (EDGE_COUNT (trap_bb->preds) == 0)
+ delete_basic_block (trap_bb);
- delete_insn (trap);
-
- /* Merge the blocks! */
- if (trap_bb != then_bb && ! else_bb)
+ /* If the non-trap block and the test are now adjacent, merge them.
+ Otherwise we must insert a direct branch. */
+ if (test_bb->next_bb == other_bb)
{
- flow_delete_block (trap_bb);
- num_removed_blocks++;
+ struct ce_if_block new_ce_info;
+ delete_insn (jump);
+ memset (&new_ce_info, '\0', sizeof (new_ce_info));
+ new_ce_info.test_bb = test_bb;
+ new_ce_info.then_bb = NULL;
+ new_ce_info.else_bb = NULL;
+ new_ce_info.join_bb = other_bb;
+ merge_if_block (&new_ce_info);
+ }
+ else
+ {
+ rtx lab, newjump;
+
+ lab = JUMP_LABEL (jump);
+ newjump = emit_jump_insn_after (gen_jump (lab), jump);
+ LABEL_NUSES (lab) += 1;
+ JUMP_LABEL (newjump) = lab;
+ emit_barrier_after (newjump);
+
+ delete_insn (jump);
}
- merge_if_block (test_bb, then_bb, else_bb, join_bb);
return TRUE;
}
+/* Subroutine of find_cond_trap: if BB contains only a trap insn,
+ return it. */
+
+static rtx
+block_has_only_trap (basic_block bb)
+{
+ rtx trap;
+
+ /* We're not the exit block. */
+ if (bb == EXIT_BLOCK_PTR)
+ return NULL_RTX;
+
+ /* The block must have no successors. */
+ if (EDGE_COUNT (bb->succs) > 0)
+ return NULL_RTX;
+
+ /* The only instruction in the THEN block must be the trap. */
+ trap = first_active_insn (bb);
+ if (! (trap == BB_END (bb)
+ && GET_CODE (PATTERN (trap)) == TRAP_IF
+ && TRAP_CONDITION (PATTERN (trap)) == const_true_rtx))
+ return NULL_RTX;
+
+ return trap;
+}
+
/* Look for IF-THEN-ELSE cases in which one of THEN or ELSE is
transformable, but not necessarily the other. There need be no
JOIN block.
- Return TRUE if we were successful at converting the the block.
+ Return TRUE if we were successful at converting the block.
Cases we'd like to look at:
/* Tests for case 1 above. */
static int
-find_if_case_1 (test_bb, then_edge, else_edge)
- basic_block test_bb;
- edge then_edge, else_edge;
+find_if_case_1 (basic_block test_bb, edge then_edge, edge else_edge)
{
basic_block then_bb = then_edge->dest;
basic_block else_bb = else_edge->dest, new_bb;
- edge then_succ = then_bb->succ;
+ int then_bb_index;
+
+ /* If we are partitioning hot/cold basic blocks, we don't want to
+ mess up unconditional or indirect jumps that cross between hot
+ and cold sections.
+
+ Basic block partitioning may result in some jumps that appear to
+ be optimizable (or blocks that appear to be mergeable), but which really
+ must be left untouched (they are required to make it safely across
+ partition boundaries). See the comments at the top of
+ bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */
+
+ if (flag_reorder_blocks_and_partition
+ && ((BB_END (then_bb)
+ && find_reg_note (BB_END (then_bb), REG_CROSSING_JUMP, NULL_RTX))
+ || (BB_END (else_bb)
+ && find_reg_note (BB_END (else_bb), REG_CROSSING_JUMP,
+ NULL_RTX))))
+ return FALSE;
/* THEN has one successor. */
- if (!then_succ || then_succ->succ_next != NULL)
+ if (EDGE_COUNT (then_bb->succs) != 1)
return FALSE;
/* THEN does not fall through, but is not strange either. */
- if (then_succ->flags & (EDGE_COMPLEX | EDGE_FALLTHRU))
+ if (EDGE_SUCC (then_bb, 0)->flags & (EDGE_COMPLEX | EDGE_FALLTHRU))
return FALSE;
/* THEN has one predecessor. */
- if (then_bb->pred->pred_next != NULL)
+ if (EDGE_COUNT (then_bb->preds) != 1)
return FALSE;
/* THEN must do something. */
return FALSE;
num_possible_if_blocks++;
- if (rtl_dump_file)
- fprintf (rtl_dump_file,
+ if (dump_file)
+ fprintf (dump_file,
"\nIF-CASE-1 found, start %d, then %d\n",
test_bb->index, then_bb->index);
/* THEN is small. */
- if (count_bb_insns (then_bb) > BRANCH_COST)
+ if (! cheap_bb_rtx_cost_p (then_bb, COSTS_N_INSNS (BRANCH_COST)))
return FALSE;
/* Registers set are dead, or are predicable. */
- if (! dead_or_predicable (test_bb, then_bb, else_bb,
- then_bb->succ->dest, 1))
+ if (! dead_or_predicable (test_bb, then_bb, else_bb,
+ EDGE_SUCC (then_bb, 0)->dest, 1))
return FALSE;
/* Conversion went ok, including moving the insns and fixing up the
jump. Adjust the CFG to match. */
- bitmap_operation (test_bb->global_live_at_end,
- else_bb->global_live_at_start,
- then_bb->global_live_at_end, BITMAP_IOR);
-
- new_bb = redirect_edge_and_branch_force (FALLTHRU_EDGE (test_bb), else_bb);
+ bitmap_ior (test_bb->global_live_at_end,
+ else_bb->global_live_at_start,
+ then_bb->global_live_at_end);
+
+
+ /* We can avoid creating a new basic block if then_bb is immediately
+ followed by else_bb, i.e. deleting then_bb allows test_bb to fall
+ thru to else_bb. */
+
+ if (then_bb->next_bb == else_bb
+ && then_bb->prev_bb == test_bb
+ && else_bb != EXIT_BLOCK_PTR)
+ {
+ redirect_edge_succ (FALLTHRU_EDGE (test_bb), else_bb);
+ new_bb = 0;
+ }
+ else
+ new_bb = redirect_edge_and_branch_force (FALLTHRU_EDGE (test_bb),
+ else_bb);
+
+ then_bb_index = then_bb->index;
+ delete_basic_block (then_bb);
+
/* Make rest of code believe that the newly created block is the THEN_BB
- block we are going to remove. */
+ block we removed. */
if (new_bb)
- new_bb->aux = then_bb->aux;
- flow_delete_block (then_bb);
+ {
+ new_bb->index = then_bb_index;
+ BASIC_BLOCK (then_bb_index) = new_bb;
+ /* Since the fallthru edge was redirected from test_bb to new_bb,
+ we need to ensure that new_bb is in the same partition as
+ test bb (you can not fall through across section boundaries). */
+ BB_COPY_PARTITION (new_bb, test_bb);
+ }
/* We've possibly created jump to next insn, cleanup_cfg will solve that
later. */
- num_removed_blocks++;
+ num_true_changes++;
num_updated_if_blocks++;
return TRUE;
/* Test for case 2 above. */
static int
-find_if_case_2 (test_bb, then_edge, else_edge)
- basic_block test_bb;
- edge then_edge, else_edge;
+find_if_case_2 (basic_block test_bb, edge then_edge, edge else_edge)
{
basic_block then_bb = then_edge->dest;
basic_block else_bb = else_edge->dest;
- edge else_succ = else_bb->succ;
+ edge else_succ;
rtx note;
+ /* If we are partitioning hot/cold basic blocks, we don't want to
+ mess up unconditional or indirect jumps that cross between hot
+ and cold sections.
+
+ Basic block partitioning may result in some jumps that appear to
+ be optimizable (or blocks that appear to be mergeable), but which really
+ must be left untouched (they are required to make it safely across
+ partition boundaries). See the comments at the top of
+ bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */
+
+ if (flag_reorder_blocks_and_partition
+ && ((BB_END (then_bb)
+ && find_reg_note (BB_END (then_bb), REG_CROSSING_JUMP, NULL_RTX))
+ || (BB_END (else_bb)
+ && find_reg_note (BB_END (else_bb), REG_CROSSING_JUMP,
+ NULL_RTX))))
+ return FALSE;
+
/* ELSE has one successor. */
- if (!else_succ || else_succ->succ_next != NULL)
+ if (EDGE_COUNT (else_bb->succs) != 1)
return FALSE;
+ else
+ else_succ = EDGE_SUCC (else_bb, 0);
/* ELSE outgoing edge is not complex. */
if (else_succ->flags & EDGE_COMPLEX)
return FALSE;
/* ELSE has one predecessor. */
- if (else_bb->pred->pred_next != NULL)
+ if (EDGE_COUNT (else_bb->preds) != 1)
return FALSE;
/* THEN is not EXIT. */
return FALSE;
/* ELSE is predicted or SUCC(ELSE) postdominates THEN. */
- note = find_reg_note (test_bb->end, REG_BR_PROB, NULL_RTX);
+ note = find_reg_note (BB_END (test_bb), REG_BR_PROB, NULL_RTX);
if (note && INTVAL (XEXP (note, 0)) >= REG_BR_PROB_BASE / 2)
;
else if (else_succ->dest->index < 0
- || TEST_BIT (post_dominators[ORIG_INDEX (then_bb)],
- ORIG_INDEX (else_succ->dest)))
+ || dominated_by_p (CDI_POST_DOMINATORS, then_bb,
+ else_succ->dest))
;
else
return FALSE;
num_possible_if_blocks++;
- if (rtl_dump_file)
- fprintf (rtl_dump_file,
+ if (dump_file)
+ fprintf (dump_file,
"\nIF-CASE-2 found, start %d, else %d\n",
test_bb->index, else_bb->index);
/* ELSE is small. */
- if (count_bb_insns (then_bb) > BRANCH_COST)
+ if (! cheap_bb_rtx_cost_p (else_bb, COSTS_N_INSNS (BRANCH_COST)))
return FALSE;
/* Registers set are dead, or are predicable. */
/* Conversion went ok, including moving the insns and fixing up the
jump. Adjust the CFG to match. */
- bitmap_operation (test_bb->global_live_at_end,
- then_bb->global_live_at_start,
- else_bb->global_live_at_end, BITMAP_IOR);
-
- flow_delete_block (else_bb);
+ bitmap_ior (test_bb->global_live_at_end,
+ then_bb->global_live_at_start,
+ else_bb->global_live_at_end);
+
+ delete_basic_block (else_bb);
- num_removed_blocks++;
+ num_true_changes++;
num_updated_if_blocks++;
/* ??? We may now fallthru from one of THEN's successors into a join
Return 1 if a memory is found. */
static int
-find_memory (px, data)
- rtx *px;
- void *data ATTRIBUTE_UNUSED;
+find_memory (rtx *px, void *data ATTRIBUTE_UNUSED)
{
- return GET_CODE (*px) == MEM;
+ return MEM_P (*px);
}
/* Used by the code above to perform the actual rtl transformations.
REVERSEP is true if the sense of the branch should be reversed. */
static int
-dead_or_predicable (test_bb, merge_bb, other_bb, new_dest, reversep)
- basic_block test_bb, merge_bb, other_bb;
- basic_block new_dest;
- int reversep;
+dead_or_predicable (basic_block test_bb, basic_block merge_bb,
+ basic_block other_bb, basic_block new_dest, int reversep)
{
- rtx head, end, jump, earliest, old_dest, new_label = NULL_RTX;
+ rtx head, end, jump, earliest = NULL_RTX, old_dest, new_label = NULL_RTX;
- jump = test_bb->end;
+ jump = BB_END (test_bb);
/* Find the extent of the real code in the merge block. */
- head = merge_bb->head;
- end = merge_bb->end;
+ head = BB_HEAD (merge_bb);
+ end = BB_END (merge_bb);
- if (GET_CODE (head) == CODE_LABEL)
+ if (LABEL_P (head))
head = NEXT_INSN (head);
- if (GET_CODE (head) == NOTE)
+ if (NOTE_P (head))
{
if (head == end)
{
head = NEXT_INSN (head);
}
- if (GET_CODE (end) == JUMP_INSN)
+ if (JUMP_P (end))
{
if (head == end)
{
if (HAVE_conditional_execution)
{
/* In the conditional execution case, we have things easy. We know
- the condition is reversable. We don't have to check life info,
- becase we're going to conditionally execute the code anyway.
+ the condition is reversible. We don't have to check life info
+ because we're going to conditionally execute the code anyway.
All that's left is making sure the insns involved can actually
be predicated. */
prob_val = GEN_INT (REG_BR_PROB_BASE - INTVAL (prob_val));
}
- if (! cond_exec_process_insns (head, end, cond, prob_val, 0))
+ if (! cond_exec_process_insns ((ce_if_block_t *)0, head, end, cond,
+ prob_val, 0))
goto cancel;
earliest = jump;
that any registers modified are dead at the branch site. */
rtx insn, cond, prev;
- regset_head merge_set_head, tmp_head, test_live_head, test_set_head;
regset merge_set, tmp, test_live, test_set;
struct propagate_block_info *pbi;
- int i, fail = 0;
+ unsigned i, fail = 0;
+ bitmap_iterator bi;
/* Check for no calls or trapping operations. */
for (insn = head; ; insn = NEXT_INSN (insn))
{
- if (GET_CODE (insn) == CALL_INSN)
+ if (CALL_P (insn))
return FALSE;
if (INSN_P (insn))
{
TEST_SET = set of registers set between EARLIEST and the
end of the block. */
- tmp = INITIALIZE_REG_SET (tmp_head);
- merge_set = INITIALIZE_REG_SET (merge_set_head);
- test_live = INITIALIZE_REG_SET (test_live_head);
- test_set = INITIALIZE_REG_SET (test_set_head);
+ tmp = ALLOC_REG_SET (®_obstack);
+ merge_set = ALLOC_REG_SET (®_obstack);
+ test_live = ALLOC_REG_SET (®_obstack);
+ test_set = ALLOC_REG_SET (®_obstack);
/* ??? bb->local_set is only valid during calculate_global_regs_live,
- so we must recompute usage for MERGE_BB. Not so bad, I suppose,
+ so we must recompute usage for MERGE_BB. Not so bad, I suppose,
since we've already asserted that MERGE_BB is small. */
propagate_block (merge_bb, tmp, merge_set, merge_set, 0);
hard registers before reload. */
if (SMALL_REGISTER_CLASSES && ! reload_completed)
{
- EXECUTE_IF_SET_IN_BITMAP
- (merge_set, 0, i,
- {
- if (i < FIRST_PSEUDO_REGISTER
- && ! fixed_regs[i]
- && ! global_regs[i])
+ EXECUTE_IF_SET_IN_BITMAP (merge_set, 0, i, bi)
+ {
+ if (i < FIRST_PSEUDO_REGISTER
+ && ! fixed_regs[i]
+ && ! global_regs[i])
fail = 1;
- });
+ }
}
/* For TEST, we're interested in a range of insns, not a whole block.
TEST_SET & merge_bb->global_live_at_start
are empty. */
- bitmap_operation (tmp, test_set, test_live, BITMAP_IOR);
- bitmap_operation (tmp, tmp, merge_set, BITMAP_AND);
- EXECUTE_IF_SET_IN_BITMAP(tmp, 0, i, fail = 1);
-
- bitmap_operation (tmp, test_set, merge_bb->global_live_at_start,
- BITMAP_AND);
- EXECUTE_IF_SET_IN_BITMAP(tmp, 0, i, fail = 1);
+ if (bitmap_intersect_p (test_set, merge_set)
+ || bitmap_intersect_p (test_live, merge_set)
+ || bitmap_intersect_p (test_set, merge_bb->global_live_at_start))
+ fail = 1;
FREE_REG_SET (tmp);
FREE_REG_SET (merge_set);
/* Move the insns out of MERGE_BB to before the branch. */
if (head != NULL)
{
- if (end == merge_bb->end)
- merge_bb->end = PREV_INSN (head);
+ if (end == BB_END (merge_bb))
+ BB_END (merge_bb) = PREV_INSN (head);
if (squeeze_notes (&head, &end))
return TRUE;
/* Main entry point for all if-conversion. */
void
-if_convert (x_life_data_ok)
- int x_life_data_ok;
+if_convert (int x_life_data_ok)
{
- int block_num;
+ basic_block bb;
+ int pass;
num_possible_if_blocks = 0;
num_updated_if_blocks = 0;
- num_removed_blocks = 0;
+ num_true_changes = 0;
life_data_ok = (x_life_data_ok != 0);
- /* Free up basic_block_for_insn so that we don't have to keep it
- up to date, either here or in merge_blocks_nomove. */
- free_basic_block_vars (1);
+ if ((! targetm.cannot_modify_jumps_p ())
+ && (!flag_reorder_blocks_and_partition || !no_new_pseudos
+ || !targetm.have_named_sections))
+ {
+ struct loops loops;
+
+ flow_loops_find (&loops);
+ mark_loop_exit_edges (&loops);
+ flow_loops_free (&loops);
+ free_dominance_info (CDI_DOMINATORS);
+ }
/* Compute postdominators if we think we'll use them. */
- post_dominators = NULL;
if (HAVE_conditional_execution || life_data_ok)
- {
- post_dominators = sbitmap_vector_alloc (n_basic_blocks, n_basic_blocks);
- calculate_dominance_info (NULL, post_dominators, CDI_POST_DOMINATORS);
- }
+ calculate_dominance_info (CDI_POST_DOMINATORS);
+
if (life_data_ok)
clear_bb_flags ();
- /* Record initial block numbers. */
- for (block_num = 0; block_num < n_basic_blocks; block_num++)
- SET_ORIG_INDEX (BASIC_BLOCK (block_num), block_num);
-
- /* Go through each of the basic blocks looking for things to convert. */
- for (block_num = 0; block_num < n_basic_blocks; )
+ /* Go through each of the basic blocks looking for things to convert. If we
+ have conditional execution, we make multiple passes to allow us to handle
+ IF-THEN{-ELSE} blocks within other IF-THEN{-ELSE} blocks. */
+ pass = 0;
+ do
{
- basic_block bb = BASIC_BLOCK (block_num);
- if (find_if_header (bb))
- block_num = bb->index;
- else
- block_num++;
+ cond_exec_changed_p = FALSE;
+ pass++;
+
+#ifdef IFCVT_MULTIPLE_DUMPS
+ if (dump_file && pass > 1)
+ fprintf (dump_file, "\n\n========== Pass %d ==========\n", pass);
+#endif
+
+ FOR_EACH_BB (bb)
+ {
+ basic_block new_bb;
+ while ((new_bb = find_if_header (bb, pass)))
+ bb = new_bb;
+ }
+
+#ifdef IFCVT_MULTIPLE_DUMPS
+ if (dump_file && cond_exec_changed_p)
+ print_rtl_with_bb (dump_file, get_insns ());
+#endif
}
+ while (cond_exec_changed_p);
+
+#ifdef IFCVT_MULTIPLE_DUMPS
+ if (dump_file)
+ fprintf (dump_file, "\n\n========== no more changes\n");
+#endif
- if (post_dominators)
- sbitmap_vector_free (post_dominators);
+ free_dominance_info (CDI_POST_DOMINATORS);
- if (rtl_dump_file)
- fflush (rtl_dump_file);
+ if (dump_file)
+ fflush (dump_file);
clear_aux_for_blocks ();
/* Rebuild life info for basic blocks that require it. */
- if (num_removed_blocks && life_data_ok)
+ if (num_true_changes && life_data_ok)
{
/* If we allocated new pseudos, we must resize the array for sched1. */
if (max_regno < max_reg_num ())
}
/* Write the final stats. */
- if (rtl_dump_file && num_possible_if_blocks > 0)
+ if (dump_file && num_possible_if_blocks > 0)
{
- fprintf (rtl_dump_file,
+ fprintf (dump_file,
"\n%d possible IF blocks searched.\n",
num_possible_if_blocks);
- fprintf (rtl_dump_file,
+ fprintf (dump_file,
"%d IF blocks converted.\n",
num_updated_if_blocks);
- fprintf (rtl_dump_file,
- "%d basic blocks deleted.\n\n\n",
- num_removed_blocks);
+ fprintf (dump_file,
+ "%d true changes made.\n\n\n",
+ num_true_changes);
}
#ifdef ENABLE_CHECKING
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