mirror/gcc
2
0
Fork 0
mirror of git://gcc.gnu.org/git/gcc.git synced 2025-04-02 06:40:25 +08:00
Code Issues Packages Projects Releases Wiki Activity

re PR tree-optimization/78720 (Illegal instruction in generated code)

Browse Source 
PR tree-optimization/78720
	* match.pd (A < 0 ? C : 0): Only optimize for signed A.  If shift
	is negative, sign extend to @1's type and than AND with C.

	* gcc.c-torture/execute/pr78720.c: New test.

Co-Authored-By: Marc Glisse <marc.glisse@inria.fr>

From-SVN: r243516
This commit is contained in:
Jakub Jelinek 2016-12-10 13:06:12 +01:00 committed by Jakub Jelinek
parent 2d4102c5cb
commit c0140e3c5d
4 changed files with 50 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
gcc/ChangeLog
View File

@ -1,3 +1,10 @@
2016-12-10 Jakub Jelinek <jakub@redhat.com>
Marc Glisse <marc.glisse@inria.fr>
PR tree-optimization/78720
* match.pd (A < 0 ? C : 0): Only optimize for signed A. If shift
is negative, sign extend to @1's type and than AND with C.
2016-12-10 Jakub Jelinek <jakub@redhat.com>
PR fortran/78758

17
gcc/match.pd
View File

@ -2768,17 +2768,22 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
(ncmp (convert:stype @0) { build_zero_cst (stype); })))))
/* If we have A < 0 ? C : 0 where C is a power of 2, convert
this into a right shift followed by ANDing with C. */
this into a right shift or sign extension followed by ANDing with C. */
(simplify
(cond
(lt @0 integer_zerop)
integer_pow2p@1 integer_zerop)
(with {
(if (!TYPE_UNSIGNED (TREE_TYPE (@0)))
(with {
int shift = element_precision (@0) - wi::exact_log2 (@1) - 1;
}
(bit_and
(convert (rshift @0 { build_int_cst (integer_type_node, shift); }))
@1)))
}
(if (shift >= 0)
(bit_and
(convert (rshift @0 { build_int_cst (integer_type_node, shift); }))
@1)
/* Otherwise ctype must be wider than TREE_TYPE (@0) and pure
sign extension followed by AND with C will achieve the effect. */
(bit_and (convert @0) @1)))))
/* When the addresses are not directly of decls compare base and offset.
This implements some remaining parts of fold_comparison address

3
gcc/testsuite/ChangeLog
View File

@ -1,5 +1,8 @@
2016-12-10 Jakub Jelinek <jakub@redhat.com>
PR tree-optimization/78720
* gcc.c-torture/execute/pr78720.c: New test.
PR fortran/78758
* gfortran.dg/pr78758.f90: New test.
* gfortran.dg/pr38868.f: Remove again bogus warning.

29
gcc/testsuite/gcc.c-torture/execute/pr78720.c Normal file
View File

@ -0,0 +1,29 @@
/* PR tree-optimization/78720 */
__attribute__((noinline, noclone)) long int
foo (signed char x)
{
return x < 0 ? 0x80000L : 0L;
}
__attribute__((noinline, noclone)) long int
bar (signed char x)
{
return x < 0 ? 0x80L : 0L;
}
__attribute__((noinline, noclone)) long int
baz (signed char x)
{
return x < 0 ? 0x20L : 0L;
}
int
main ()
{
if (foo (-1) != 0x80000L || bar (-1) != 0x80L || baz (-1) != 0x20L
|| foo (0) != 0L || bar (0) != 0L || baz (0) != 0L
|| foo (31) != 0L || bar (31) != 0L || baz (31) != 0L)
__builtin_abort ();
return 0;
}