git
/
gcc
mirror of git://gcc.gnu.org/git/gcc.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

re PR tree-optimization/69615 (0 to limit signed range checks don't always use unsigned compare) 

PR tree-optimization/69615
	* tree-ssa-reassoc.c (optimize_range_tests_var_bound): If rhs2 is lhs
	of a cast from a same precision integral SSA_NAME in a bb dominated
	by first_bb, retry with rhs2 set to the rhs1 of the cast.  Don't emit
	cast to utype if rhs2 has already a compatible type.

	* gcc.dg/tree-ssa/pr69615.c: New test.

From-SVN: r261264
This commit is contained in:
Jakub Jelinek 2018-06-07 09:41:18 +02:00 committed by Jakub Jelinek
parent b2bf825892
commit ca6b7410dd
4 changed files with 61 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
gcc/ChangeLog
View File

@ -1,3 +1,11 @@
2018-06-07 Jakub Jelinek <jakub@redhat.com>
PR tree-optimization/69615
* tree-ssa-reassoc.c (optimize_range_tests_var_bound): If rhs2 is lhs
of a cast from a same precision integral SSA_NAME in a bb dominated
by first_bb, retry with rhs2 set to the rhs1 of the cast. Don't emit
cast to utype if rhs2 has already a compatible type.
2018-06-07 Richard Biener <rguenther@suse.de>
PR tree-optimization/85935

5
gcc/testsuite/ChangeLog
View File

@ -1,3 +1,8 @@
2018-06-07 Jakub Jelinek <jakub@redhat.com>
PR tree-optimization/69615
* gcc.dg/tree-ssa/pr69615.c: New test.
2018-06-07 Richard Biener <rguenther@suse.de>
PR tree-optimization/85935

16
gcc/testsuite/gcc.dg/tree-ssa/pr69615.c Normal file
View File

@ -0,0 +1,16 @@
/* PR tree-optimization/69615 */
/* { dg-do compile } */
/* { dg-options "-O2 -fdump-tree-optimized" } */
/* { dg-final { scan-tree-dump-not " >= 0" "optimized" } } */
/* { dg-final { scan-tree-dump-not " < 0" "optimized" } } */
extern void foo (void);
void
bar (int z, unsigned int y)
{
long long x = z;
y &= 0xf;
if (x >= 0 && x < (int) y)
foo ();
}

45
gcc/tree-ssa-reassoc.c
View File

@ -3172,7 +3172,7 @@ optimize_range_tests_var_bound (enum tree_code opcode, int first, int length,
to (unsigned) k_32 < (unsigned) iftmp.0_44, then we would execute
those stmts even for negative k_32 and the value ranges would be no
longer guaranteed and so the optimization would be invalid. */
if (opcode == ERROR_MARK)
while (opcode == ERROR_MARK)
{
gimple *g = SSA_NAME_DEF_STMT (rhs2);
basic_block bb2 = gimple_bb (g);
@ -3182,21 +3182,37 @@ optimize_range_tests_var_bound (enum tree_code opcode, int first, int length,
{
/* As an exception, handle a few common cases. */
if (gimple_assign_cast_p (g)
&& INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_rhs1 (g)))
&& TYPE_UNSIGNED (TREE_TYPE (gimple_assign_rhs1 (g)))
&& (TYPE_PRECISION (TREE_TYPE (rhs2))
> TYPE_PRECISION (TREE_TYPE (gimple_assign_rhs1 (g)))))
/* Zero-extension is always ok. */ ;
&& INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_rhs1 (g))))
{
tree op0 = gimple_assign_rhs1 (g);
if (TYPE_UNSIGNED (TREE_TYPE (op0))
&& (TYPE_PRECISION (TREE_TYPE (rhs2))
> TYPE_PRECISION (TREE_TYPE (op0))))
/* Zero-extension is always ok. */
break;
else if (TYPE_PRECISION (TREE_TYPE (rhs2))
== TYPE_PRECISION (TREE_TYPE (op0))
&& TREE_CODE (op0) == SSA_NAME)
{
/* Cast from signed to unsigned or vice versa. Retry
with the op0 as new rhs2. */
rhs2 = op0;
continue;
}
}
else if (is_gimple_assign (g)
&& gimple_assign_rhs_code (g) == BIT_AND_EXPR
&& TREE_CODE (gimple_assign_rhs2 (g)) == INTEGER_CST
&& !wi::neg_p (wi::to_wide (gimple_assign_rhs2 (g))))
/* Masking with INTEGER_CST with MSB clear is always ok
too. */ ;
else
continue;
too. */
break;
rhs2 = NULL_TREE;
}
break;
}
if (rhs2 == NULL_TREE)
continue;
wide_int nz = get_nonzero_bits (rhs2);
if (wi::neg_p (nz))
@ -3253,10 +3269,13 @@ optimize_range_tests_var_bound (enum tree_code opcode, int first, int length,
gimple_set_uid (g, uid);
rhs1 = gimple_assign_lhs (g);
gsi_insert_before (&gsi, g, GSI_SAME_STMT);
g = gimple_build_assign (make_ssa_name (utype), NOP_EXPR, rhs2);
gimple_set_uid (g, uid);
rhs2 = gimple_assign_lhs (g);
gsi_insert_before (&gsi, g, GSI_SAME_STMT);
if (!useless_type_conversion_p (utype, TREE_TYPE (rhs2)))
{
g = gimple_build_assign (make_ssa_name (utype), NOP_EXPR, rhs2);
gimple_set_uid (g, uid);
rhs2 = gimple_assign_lhs (g);
gsi_insert_before (&gsi, g, GSI_SAME_STMT);
}
if (tree_swap_operands_p (rhs1, rhs2))
{
std::swap (rhs1, rhs2);