------- Comment #1 from irar at il dot ibm dot com 2009-01-05 13:19 -------
Here is a reduced testcase:
program test_elemental
implicit none
integer, dimension (2, 4) :: a
integer, dimension (2, 4) :: b
integer(kind = 8), dimension(2) :: c
a = reshape ((/2, 3, 4, 5, 6, 7, 8, 9/), (/2, 4/))
b = 0
a = e_fn (a(:, 4:1:-1), 1 + b)
! This tests intrinsic elemental conversion functions.
c = 2 * a(1, 1)
if (any (c .ne. 14)) call abort
! This triggered bug due to building ss chains in the wrong order.
b = 0;
a = a - e_fn (a, b)
if (any (a .ne. 0)) call abort
contains
elemental integer(kind=4) function e_fn (p, q)
integer, intent(in) :: p, q
e_fn = p - q
end function
end program
The problem is that dse2 removes the stores to array A.4 which is used by the
vectorized code:
A.4[0] = D.1635_155;
...
A.4[7] = D.1635_165;
vect_pA.67_156 = (vector integer(kind=4) *) &A.4;
vect_pa.73_197 = (vector integer(kind=4) *) &a;
vect_var_.68_254 = *vect_pA.67_156;
*vect_pa.73_197 = vect_var_.68_254;
vect_pA.63_256 = vect_pA.67_156 + 16;
vect_pa.69_257 = vect_pa.73_197 + 16;
vect_var_.68_170 = *vect_pA.63_256;
*vect_pa.69_257 = vect_var_.68_170;
We propagate alias info from the scalar to vector ref in
vect_create_data_ref_ptr() (in tree-vect-transform.c):
/** (2) Add aliasing information to the new vector-pointer:
(The points-to info (DR_PTR_INFO) may be defined later.) **/
tag = DR_SYMBOL_TAG (dr);
gcc_assert (tag);
/* If tag is a variable (and NOT_A_TAG) than a new symbol memory
tag must be created with tag added to its may alias list. */
if (!MTAG_P (tag))
new_type_alias (vect_ptr, tag, DR_REF (dr));
else
set_symbol_mem_tag (vect_ptr, tag);
Those lines do not exist on the branch. Do you take care of this somewhere
else?
Ira
--
irar at il dot ibm dot com changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Ever Confirmed|0 |1
Last reconfirmed|0000-00-00 00:00:00 |2009-01-05 13:19:53
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38721
