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Fix thinko in early bail out in tree-switch-conversion.

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2019-09-02  Martin Liska  <mliska@suse.cz>

	* tree-switch-conversion.c (jump_table_cluster::find_jump_tables):
	Bail out when we'll end up with the same number of clusters as
	at the beginning.
	(bit_test_cluster::find_bit_tests): Likewise for bit tests.
	(jump_table_cluster::can_be_handled): Remove the guard
	as it's already handled in ::is_enabled.  Allocate output
	after early bail out.

From-SVN: r275293
This commit is contained in:
Martin Liska 2019-09-02 09:09:39 +02:00 • committed by Martin Liska
parent ae0d3f6a59
commit 1acbaa7530
2 changed files with 18 additions and 10 deletions
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10
gcc/ChangeLog
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@ -1,3 +1,13 @@
2019-09-02 Martin Liska <mliska@suse.cz>
* tree-switch-conversion.c (jump_table_cluster::find_jump_tables):
Bail out when we'll end up with the same number of clusters as
at the beginning.
(bit_test_cluster::find_bit_tests): Likewise for bit tests.
(jump_table_cluster::can_be_handled): Remove the guard
as it's already handled in ::is_enabled. Allocate output
after early bail out.
2019-09-02 Martin Liska <mliska@suse.cz>
PR gcov-profile/91601

18
gcc/tree-switch-conversion.c
View file

@ -1214,14 +1214,14 @@ jump_table_cluster::find_jump_tables (vec<cluster *> &clusters)
}
/* No result. */
if (min[l].m_count == INT_MAX)
if (min[l].m_count == l)
return clusters.copy ();
vec<cluster *> output;
output.create (4);
/* Find and build the clusters. */
for (int end = l;;)
for (unsigned int end = l;;)
{
int start = min[end].m_start;
@ -1258,11 +1258,9 @@ jump_table_cluster::can_be_handled (const vec<cluster *> &clusters,
make a sequence of conditional branches instead of a dispatch.
The definition of "much bigger" depends on whether we are
optimizing for size or for speed. */
if (!flag_jump_tables)
return false;
optimizing for size or for speed.
/* For algorithm correctness, jump table for a single case must return
For algorithm correctness, jump table for a single case must return
true. We bail out in is_beneficial if it's called just for
a single case. */
if (start == end)
@ -1312,9 +1310,6 @@ jump_table_cluster::is_beneficial (const vec<cluster *> &,
vec<cluster *>
bit_test_cluster::find_bit_tests (vec<cluster *> &clusters)
{
vec<cluster *> output;
output.create (4);
unsigned l = clusters.length ();
auto_vec<min_cluster_item> min;
min.reserve (l + 1);
@ -1337,9 +1332,12 @@ bit_test_cluster::find_bit_tests (vec<cluster *> &clusters)
}
/* No result. */
if (min[l].m_count == INT_MAX)
if (min[l].m_count == l)
return clusters.copy ();
vec<cluster *> output;
output.create (4);
/* Find and build the clusters. */
for (unsigned end = l;;)
{