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tree-ssa-threadedge.c (simplify_control_stmt_condition): Look deeper into the SSA_NAME_VALUE chain.

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tree-optimization/61607
	* tree-ssa-threadedge.c (simplify_control_stmt_condition): Look
	deeper into the SSA_NAME_VALUE chain.

	tree-optimization/61607
	* gcc.dg/tree-ssa/pr61607.c: New test.

From-SVN: r212149
This commit is contained in:
Jeff Law 2014-06-30 08:08:50 -06:00 committed by Jeff Law
parent 6a7253a4a9
commit 4f82fed2f6
4 changed files with 67 additions and 10 deletions
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6
gcc/ChangeLog
View File

@ -1,3 +1,9 @@
2014-06-30 Jeff Law <law@redhat.com>
PR tree-optimization/61607
* tree-ssa-threadedge.c (simplify_control_stmt_condition): Look
deeper into the SSA_NAME_VALUE chain.
2014-06-30 Marek Polacek <polacek@redhat.com>
* convert.c (convert_to_integer): Don't instrument conversions if the

5
gcc/testsuite/ChangeLog
View File

@ -1,3 +1,8 @@
2014-06-30 Jeff Law <law@redhat.com>
PR tree-optimization/61607
* gcc.dg/tree-ssa/pr61607.c: New test.
2014-06-30 Marek Polacek <polacek@redhat.com>
* c-c++-common/ubsan/attrib-2.c: New test.

29
gcc/testsuite/gcc.dg/tree-ssa/pr61607.c Normal file
View File

@ -0,0 +1,29 @@
/* { dg-do compile } */
/* { dg-options "-Os -fno-tree-fre -fdump-tree-dom1" } */
void foo(int *);
void f2(int dst[3], int R)
{
int i, inter[2];
_Bool inter0p = 0;
_Bool inter1p = 0;
for (i = 1; i < R; i++)
{
inter0p = 1;
inter1p = 1;
}
if (inter0p)
inter[0] = 1;
if (inter1p)
inter[1] = 1;
foo(inter);
}
/* There should be precisely two conditionals. One for the loop condition
and one for the test after the loop. Previously we failed to eliminate
the second conditional after the loop. */
/* { dg-final { scan-tree-dump-times "if" 2 "dom1"} } */
/* { dg-final { cleanup-tree-dump "dom1" } } */

37
gcc/tree-ssa-threadedge.c
View File

@ -542,16 +542,26 @@ simplify_control_stmt_condition (edge e,
/* Get the current value of both operands. */
if (TREE_CODE (op0) == SSA_NAME)
{
tree tmp = SSA_NAME_VALUE (op0);
if (tmp)
op0 = tmp;
for (int i = 0; i < 2; i++)
{
if (TREE_CODE (op0) == SSA_NAME
&& SSA_NAME_VALUE (op0))
op0 = SSA_NAME_VALUE (op0);
else
break;
}
}
if (TREE_CODE (op1) == SSA_NAME)
{
tree tmp = SSA_NAME_VALUE (op1);
if (tmp)
op1 = tmp;
for (int i = 0; i < 2; i++)
{
if (TREE_CODE (op1) == SSA_NAME
&& SSA_NAME_VALUE (op1))
op1 = SSA_NAME_VALUE (op1);
else
break;
}
}
if (handle_dominating_asserts)
@ -625,10 +635,17 @@ simplify_control_stmt_condition (edge e,
It is possible to get loops in the SSA_NAME_VALUE chains
(consider threading the backedge of a loop where we have
a loop invariant SSA_NAME used in the condition. */
if (cached_lhs
&& TREE_CODE (cached_lhs) == SSA_NAME
&& SSA_NAME_VALUE (cached_lhs))
cached_lhs = SSA_NAME_VALUE (cached_lhs);
if (cached_lhs)
{
for (int i = 0; i < 2; i++)
{
if (TREE_CODE (cached_lhs) == SSA_NAME
&& SSA_NAME_VALUE (cached_lhs))
cached_lhs = SSA_NAME_VALUE (cached_lhs);
else
break;
}
}
/* If we're dominated by a suitable ASSERT_EXPR, then
update CACHED_LHS appropriately. */