https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94482
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Summary|Inserting into vector with |[8/9/10 Regression]
|optimization enabled on x86 |Inserting into vector with
|generates incorrect result |optimization enabled on x86
| |generates incorrect result
Target Milestone|--- |8.5
--- Comment #14 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
The above testcase FAILs with all of 7/8/9/10, works with 6.
-fno-tree-sra fixes it.
Unless BIT_FIELD_REF with a non-SSA_NAME first operand is invalid on the lhs of
assignment, I believe this is a SRA bug.
Before SRA we have:
z.j = { 0, 0, 0, 0 };
BIT_FIELD_REF <z.i, 64, 0> = 1729;
_11 = z.j;
z ={v} {CLOBBER};
z.j = _11;
BIT_FIELD_REF <z.i, 64, 64> = 2;
_6 = z.j;
z ={v} {CLOBBER};
z.j = _6;
_3 = BIT_FIELD_REF <z.i, 64, 0>;
if (_3 != 1729)
but SRA transforms it into:
z$j = { 0, 0, 0, 0 };
BIT_FIELD_REF <z.i, 64, 0> = 1729;
_19 = MEM[(union U *)&z];
z$j = _19;
_1 = z$j;
_11 = _1;
z$j ={v} {CLOBBER};
z$j = _11;
BIT_FIELD_REF <z.i, 64, 64> = 2;
_15 = MEM[(union U *)&z];
z$j = _15;
_12 = z$j;
_6 = _12;
z$j ={v} {CLOBBER};
z$j_22 = _6;
MEM[(union U *)&z] = z$j_22;
_3 = BIT_FIELD_REF <z.i, 64, 0>;
if (_3 != 1729)
which is definitely not equivalent.
