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tree-ssa-loop-manip.c (tree_unroll_loop): Make it a wrapper over ...

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* tree-ssa-loop-manip.c (tree_unroll_loop): Make it a wrapper over ...
	(tree_transform_and_unroll_loop): New.
	* tree-flow.h (transform_callback, tree_transform_and_unroll_loop):
	Declare.

From-SVN: r120650
This commit is contained in:
Zdenek Dvorak 2007-01-10 21:32:36 +00:00
parent 6b074ef6a0
commit 567b96ed38
3 changed files with 93 additions and 47 deletions
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15
gcc/ChangeLog
View File

@ -1,3 +1,10 @@
2007-01-10 Zdenek Dvorak <dvorakz@suse.cz>
* tree-ssa-loop-manip.c (tree_unroll_loop): Make it a wrapper over ...
(tree_transform_and_unroll_loop): New.
* tree-flow.h (transform_callback, tree_transform_and_unroll_loop):
Declare.
2007-01-10 Robert Kennedy <jimbob@google.com>
* fold-const.c (fold_comparison): Fold comparisons like (x *
@ -24,11 +31,11 @@
* config/bfin/t-bfin, config/bfin/t-bfin-elf: Remove GCC_CFLAGS.
2007-01-10 Razya Ladelsky <razya@il.ibm.com>
* function.c (get_last_funcdef_no): New function.
* function.c (get_last_funcdef_no): New function.
* function.h (get_last_funcdef_no): Declare.
* tree-inline.c (initialize_cfun): Add initialization.
(tree_function_versioning): Cleanup.
* tree-inline.c (initialize_cfun): Add initialization.
(tree_function_versioning): Cleanup.
2007-01-10 Jan Hubicka <jh@suse.cz>

4
gcc/tree-flow.h
View File

@ -908,6 +908,10 @@ bool can_unroll_loop_p (struct loop *loop, unsigned factor,
struct tree_niter_desc *niter);
void tree_unroll_loop (struct loop *, unsigned,
edge, struct tree_niter_desc *);
typedef void (*transform_callback)(struct loop *, void *);
void tree_transform_and_unroll_loop (struct loop *, unsigned,
edge, struct tree_niter_desc *,
transform_callback, void *);
bool contains_abnormal_ssa_name_p (tree);
/* In tree-ssa-threadedge.c */

121
gcc/tree-ssa-loop-manip.c
View File

@ -803,14 +803,20 @@ determine_exit_conditions (struct loop *loop, struct tree_niter_desc *desc,
if (st)
break;
post;
} */
}
Before the loop is unrolled, TRANSFORM is called for it (only for the
unrolled loop, but not for its versioned copy). DATA is passed to
TRANSFORM. */
/* Probability in % that the unrolled loop is entered. Just a guess. */
#define PROB_UNROLLED_LOOP_ENTERED 90
void
tree_unroll_loop (struct loop *loop, unsigned factor,
edge exit, struct tree_niter_desc *desc)
tree_transform_and_unroll_loop (struct loop *loop, unsigned factor,
edge exit, struct tree_niter_desc *desc,
transform_callback transform,
void *data)
{
tree dont_exit, exit_if, ctr_before, ctr_after;
tree enter_main_cond, exit_base, exit_step, exit_bound;
@ -859,24 +865,7 @@ tree_unroll_loop (struct loop *loop, unsigned factor,
gcc_assert (new_loop != NULL);
update_ssa (TODO_update_ssa);
/* Unroll the loop and remove the old exits. */
dont_exit = ((exit->flags & EDGE_TRUE_VALUE)
? boolean_false_node
: boolean_true_node);
exit_if = last_stmt (exit->src);
COND_EXPR_COND (exit_if) = dont_exit;
update_stmt (exit_if);
wont_exit = sbitmap_alloc (factor);
sbitmap_ones (wont_exit);
ok = tree_duplicate_loop_to_header_edge
(loop, loop_latch_edge (loop), factor - 1,
wont_exit, exit, NULL, DLTHE_FLAG_UPDATE_FREQ);
free (wont_exit);
gcc_assert (ok);
update_ssa (TODO_update_ssa);
/* Determine the probability of the exit edge. */
/* Determine the probability of the exit edge of the unrolled loop. */
new_est_niter = est_niter / factor;
/* Without profile feedback, loops for that we do not know a better estimate
@ -892,31 +881,24 @@ tree_unroll_loop (struct loop *loop, unsigned factor,
new_est_niter = 5;
}
/* Ensure that the frequencies in the loop match the new estimated
number of iterations. */
freq_h = loop->header->frequency;
freq_e = EDGE_FREQUENCY (loop_preheader_edge (loop));
if (freq_h != 0)
scale_loop_frequencies (loop, freq_e * new_est_niter, freq_h);
/* Prepare the cfg and update the phi nodes. */
rest = loop_preheader_edge (new_loop)->src;
precond_edge = single_pred_edge (rest);
split_edge (loop_latch_edge (loop));
exit_bb = single_pred (loop->latch);
/* For the moment, make it appear that the new exit edge cannot
be taken. */
bsi = bsi_last (exit_bb);
exit_if = build_if_stmt (boolean_true_node,
tree_block_label (loop->latch),
tree_block_label (rest));
bsi_insert_after (&bsi, exit_if, BSI_NEW_STMT);
new_exit = make_edge (exit_bb, rest, EDGE_FALSE_VALUE | irr);
new_exit->count = loop_preheader_edge (loop)->count;
new_exit->probability = REG_BR_PROB_BASE / new_est_niter;
rest->count += new_exit->count;
rest->frequency += EDGE_FREQUENCY (new_exit);
new_exit->count = 0;
new_exit->probability = 0;
new_nonexit = single_pred_edge (loop->latch);
new_nonexit->flags = EDGE_TRUE_VALUE;
new_nonexit->probability = REG_BR_PROB_BASE - new_exit->probability;
scale_bbs_frequencies_int (&loop->latch, 1, new_nonexit->probability,
REG_BR_PROB_BASE);
old_entry = loop_preheader_edge (loop);
new_entry = loop_preheader_edge (new_loop);
@ -954,16 +936,57 @@ tree_unroll_loop (struct loop *loop, unsigned factor,
SET_USE (op, new_init);
}
/* Transform the loop. */
if (transform)
(*transform) (loop, data);
/* Unroll the loop and remove the old exits. */
dont_exit = ((exit->flags & EDGE_TRUE_VALUE)
? boolean_false_node
: boolean_true_node);
exit_if = last_stmt (exit->src);
COND_EXPR_COND (exit_if) = dont_exit;
update_stmt (exit_if);
wont_exit = sbitmap_alloc (factor);
sbitmap_ones (wont_exit);
ok = tree_duplicate_loop_to_header_edge
(loop, loop_latch_edge (loop), factor - 1,
wont_exit, exit, NULL, DLTHE_FLAG_UPDATE_FREQ);
free (wont_exit);
gcc_assert (ok);
update_ssa (TODO_update_ssa);
/* Ensure that the frequencies in the loop match the new estimated
number of iterations, and change the probability of the new
exit edge. */
freq_h = loop->header->frequency;
freq_e = EDGE_FREQUENCY (loop_preheader_edge (loop));
if (freq_h != 0)
scale_loop_frequencies (loop, freq_e * (new_est_niter + 1), freq_h);
exit_bb = single_pred (loop->latch);
new_exit = find_edge (exit_bb, rest);
new_exit->count = loop_preheader_edge (loop)->count;
new_exit->probability = REG_BR_PROB_BASE / (new_est_niter + 1);
rest->count += new_exit->count;
rest->frequency += EDGE_FREQUENCY (new_exit);
new_nonexit = single_pred_edge (loop->latch);
new_nonexit->probability = REG_BR_PROB_BASE - new_exit->probability;
scale_bbs_frequencies_int (&loop->latch, 1, new_nonexit->probability,
REG_BR_PROB_BASE);
/* Finally create the new counter for number of iterations and add the new
exit instruction. */
bsi = bsi_last (exit_bb);
exit_if = bsi_stmt (bsi);
create_iv (exit_base, exit_step, NULL_TREE, loop,
&bsi, true, &ctr_before, &ctr_after);
exit_if = build_if_stmt (build2 (exit_cmp, boolean_type_node, ctr_after,
exit_bound),
tree_block_label (loop->latch),
tree_block_label (rest));
bsi_insert_after (&bsi, exit_if, BSI_NEW_STMT);
&bsi, false, &ctr_before, &ctr_after);
COND_EXPR_COND (exit_if) = build2 (exit_cmp, boolean_type_node, ctr_after,
exit_bound);
update_stmt (exit_if);
#ifdef ENABLE_CHECKING
verify_flow_info ();
@ -972,3 +995,15 @@ tree_unroll_loop (struct loop *loop, unsigned factor,
verify_loop_closed_ssa ();
#endif
}
/* Wrapper over tree_transform_and_unroll_loop for case we do not
want to transform the loop before unrolling. The meaning
of the arguments is the same as for tree_transform_and_unroll_loop. */
void
tree_unroll_loop (struct loop *loop, unsigned factor,
edge exit, struct tree_niter_desc *desc)
{
tree_transform_and_unroll_loop (loop, factor, exit, desc,
NULL, NULL);
}