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Commit 377afcd5 by Martin Liska Committed by Martin Liska
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Fix probability for bit-tests. 

2018-08-27  Martin Liska  <mliska@suse.cz>

	* tree-switch-conversion.c (bit_test_cluster::find_bit_tests):
        Add new argument to bit_test_cluster constructor.
	(bit_test_cluster::emit): Set bits really number of values
        handlel by a test.
	(bit_test_cluster::hoist_edge_and_branch_if_true): Add
        probability argument.
	* tree-switch-conversion.h (struct bit_test_cluster):
        Add m_handles_entire_switch.
2018-08-27  Martin Liska  <mliska@suse.cz>

	* gcc.dg/tree-ssa/switch-2.c: New test.

From-SVN: r263878
parent dbdfaaba
Showing with 82 additions and 16 deletions
gcc/ChangeLog
2018-08-27 Martin Liska <mliska@suse.cz>
* tree-switch-conversion.c (bit_test_cluster::find_bit_tests):
Add new argument to bit_test_cluster constructor.
(bit_test_cluster::emit): Set bits really number of values
handlel by a test.
(bit_test_cluster::hoist_edge_and_branch_if_true): Add
probability argument.
* tree-switch-conversion.h (struct bit_test_cluster):
Add m_handles_entire_switch.
2018-08-27 Martin Liska <mliska@suse.cz>
PR tree-optimization/86702
* tree-switch-conversion.c (jump_table_cluster::emit):
Make probabilities even for values in jump table
......
gcc/testsuite/ChangeLog
2018-08-27 Martin Liska <mliska@suse.cz>
* gcc.dg/tree-ssa/switch-2.c: New test.
2018-08-27 Richard Biener <rguenther@suse.de>
* g++.dg/torture/20180705-1.C: New testcase.
......
gcc/testsuite/gcc.dg/tree-ssa/switch-2.c 0 → 100644
/* { dg-do compile { target { { x86_64-*-* aarch64-*-* ia64-*-* powerpc64-*-* } && lp64 } } } */
/* { dg-options "-O2 -fdump-tree-switchlower1" } */
int global;
int foo (int x)
{
switch (x) {
case 0:
case 10:
return 1;
case 20:
case 30:
case 62:
return 2;
case 1000:
case 1010:
case 1025 ... 1030:
return 1;
default:
return 0;
}
}
/* { dg-final { scan-tree-dump ";; GIMPLE switch case clusters: BT:0-62 BT:1000-1030" "switchlower1" } } */
gcc/tree-switch-conversion.c
......@@ -1279,12 +1279,16 @@ bit_test_cluster::find_bit_tests (vec<cluster *> &clusters)
return clusters.copy ();
/* Find and build the clusters. */
for (int end = l;;)
for (unsigned end = l;;)
{
int start = min[end].m_start;
if (is_beneficial (clusters, start, end - 1))
output.safe_push (new bit_test_cluster (clusters, start, end - 1));
{
bool entire = start == 0 && end == clusters.length ();
output.safe_push (new bit_test_cluster (clusters, start, end - 1,
entire));
}
else
for (int i = end - 1; i >= start; i--)
output.safe_push (clusters[i]);
......@@ -1434,6 +1438,7 @@ bit_test_cluster::emit (tree index_expr, tree index_type,
tree minval = get_low ();
tree maxval = get_high ();
tree range = int_const_binop (MINUS_EXPR, maxval, minval);
unsigned HOST_WIDE_INT bt_range = get_range (minval, maxval);
/* Go through all case labels, and collect the case labels, profile
counts, and other information we need to build the branch tests. */
......@@ -1452,11 +1457,11 @@ bit_test_cluster::emit (tree index_expr, tree index_type,
test[k].mask = wi::zero (prec);
test[k].target_bb = n->m_case_bb;
test[k].label = n->m_case_label_expr;
test[k].bits = 1;
test[k].bits = 0;
count++;
}
else
test[k].bits++;
test[k].bits += n->get_range (n->get_low (), n->get_high ());
lo = tree_to_uhwi (int_const_binop (MINUS_EXPR, n->get_low (), minval));
if (n->get_high () == NULL_TREE)
......@@ -1513,14 +1518,20 @@ bit_test_cluster::emit (tree index_expr, tree index_type,
/*simple=*/true, NULL_TREE,
/*before=*/true, GSI_SAME_STMT);
/* if (idx > range) goto default */
range = force_gimple_operand_gsi (&gsi,
if (m_handles_entire_switch)
{
/* if (idx > range) goto default */
range
= force_gimple_operand_gsi (&gsi,
fold_convert (unsigned_index_type, range),
/*simple=*/true, NULL_TREE,
/*before=*/true, GSI_SAME_STMT);
tmp = fold_build2 (GT_EXPR, boolean_type_node, idx, range);
basic_block new_bb = hoist_edge_and_branch_if_true (&gsi, tmp, default_bb);
gsi = gsi_last_bb (new_bb);
tmp = fold_build2 (GT_EXPR, boolean_type_node, idx, range);
basic_block new_bb
= hoist_edge_and_branch_if_true (&gsi, tmp, default_bb,
profile_probability::unlikely ());
gsi = gsi_last_bb (new_bb);
}
/* csui = (1 << (word_mode) idx) */
csui = make_ssa_name (word_type_node);
......@@ -1533,17 +1544,23 @@ bit_test_cluster::emit (tree index_expr, tree index_type,
gsi_insert_before (&gsi, shift_stmt, GSI_SAME_STMT);
update_stmt (shift_stmt);
profile_probability prob = profile_probability::always ();
/* for each unique set of cases:
if (const & csui) goto target */
for (k = 0; k < count; k++)
{
prob = profile_probability::always ().apply_scale (test[k].bits,
bt_range);
bt_range -= test[k].bits;
tmp = wide_int_to_tree (word_type_node, test[k].mask);
tmp = fold_build2 (BIT_AND_EXPR, word_type_node, csui, tmp);
tmp = force_gimple_operand_gsi (&gsi, tmp,
/*simple=*/true, NULL_TREE,
/*before=*/true, GSI_SAME_STMT);
tmp = fold_build2 (NE_EXPR, boolean_type_node, tmp, word_mode_zero);
new_bb = hoist_edge_and_branch_if_true (&gsi, tmp, test[k].target_bb);
basic_block new_bb
= hoist_edge_and_branch_if_true (&gsi, tmp, test[k].target_bb, prob);
gsi = gsi_last_bb (new_bb);
}
......@@ -1551,7 +1568,8 @@ bit_test_cluster::emit (tree index_expr, tree index_type,
gcc_assert (EDGE_COUNT (gsi_bb (gsi)->succs) == 0);
/* If nothing matched, go to the default label. */
make_edge (gsi_bb (gsi), default_bb, EDGE_FALLTHRU);
edge e = make_edge (gsi_bb (gsi), default_bb, EDGE_FALLTHRU);
e->probability = profile_probability::always ();
}
/* Split the basic block at the statement pointed to by GSIP, and insert
......@@ -1571,7 +1589,8 @@ bit_test_cluster::emit (tree index_expr, tree index_type,
basic_block
bit_test_cluster::hoist_edge_and_branch_if_true (gimple_stmt_iterator *gsip,
tree cond, basic_block case_bb)
tree cond, basic_block case_bb,
profile_probability prob)
{
tree tmp;
gcond *cond_stmt;
......@@ -1579,6 +1598,7 @@ bit_test_cluster::hoist_edge_and_branch_if_true (gimple_stmt_iterator *gsip,
basic_block new_bb, split_bb = gsi_bb (*gsip);
edge e_true = make_edge (split_bb, case_bb, EDGE_TRUE_VALUE);
e_true->probability = prob;
gcc_assert (e_true->src == split_bb);
tmp = force_gimple_operand_gsi (gsip, cond, /*simple=*/true, NULL,
......
gcc/tree-switch-conversion.h
......@@ -329,8 +329,10 @@ This transformation was contributed by Roger Sayle, see this e-mail:
struct bit_test_cluster: public group_cluster
{
/* Constructor. */
bit_test_cluster (vec<cluster *> &clusters, unsigned start, unsigned end)
:group_cluster (clusters, start, end)
bit_test_cluster (vec<cluster *> &clusters, unsigned start, unsigned end,
bool handles_entire_switch)
:group_cluster (clusters, start, end),
m_handles_entire_switch (handles_entire_switch)
{}
cluster_type
......@@ -396,7 +398,11 @@ struct bit_test_cluster: public group_cluster
Returns the newly created basic block. */
static basic_block hoist_edge_and_branch_if_true (gimple_stmt_iterator *gsip,
tree cond,
basic_block case_bb);
basic_block case_bb,
profile_probability prob);
/* True when the jump table handles an entire switch statement. */
bool m_handles_entire_switch;
/* Maximum number of different basic blocks that can be handled by
a bit test. */
......
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