With the rewrite of aggregate copy handling in r16-2729-g0d276cd378e7a4
there's an error introduced which accumulates extra_off even if we
throw away some of the tentative component consumption. The following
fixes this.
Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.
* tree-ssa-sccvn.cc (vn_reference_lookup_3): Only tentatively
accumulate extra_off when tentatively consuming components
during aggregate copy handling.
---
gcc/tree-ssa-sccvn.cc | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)
diff --git a/gcc/tree-ssa-sccvn.cc b/gcc/tree-ssa-sccvn.cc
index 16343d2a407..ed87ffc2286 100644
--- a/gcc/tree-ssa-sccvn.cc
+++ b/gcc/tree-ssa-sccvn.cc
@@ -3615,7 +3615,7 @@ vn_reference_lookup_3 (ao_ref *ref, tree vuse, void
*data_,
if (i > 0)
{
int temi = i - 1;
- extra_off = vr->operands[i].off;
+ poly_int64 tem_extra_off = extra_off + vr->operands[i].off;
while (temi >= 0
&& known_ne (vr->operands[temi].off, -1))
{
@@ -3627,20 +3627,21 @@ vn_reference_lookup_3 (ao_ref *ref, tree vuse, void
*data_,
i = temi;
/* Strip the component that was type matched to
the MEM_REF. */
- extra_off += vr->operands[i].off - lhs_ops[j].off;
+ extra_off = (tem_extra_off
+ + vr->operands[i].off - lhs_ops[j].off);
i--, j--;
/* Strip further equal components. */
found = true;
break;
}
- extra_off += vr->operands[temi].off;
+ tem_extra_off += vr->operands[temi].off;
temi--;
}
}
if (!found && j > 0)
{
int temj = j - 1;
- extra_off = -lhs_ops[j].off;
+ poly_int64 tem_extra_off = extra_off - lhs_ops[j].off;
while (temj >= 0
&& known_ne (lhs_ops[temj].off, -1))
{
@@ -3652,13 +3653,14 @@ vn_reference_lookup_3 (ao_ref *ref, tree vuse, void
*data_,
j = temj;
/* Strip the component that was type matched to
the MEM_REF. */
- extra_off += vr->operands[i].off - lhs_ops[j].off;
+ extra_off = (tem_extra_off
+ + vr->operands[i].off - lhs_ops[j].off);
i--, j--;
/* Strip further equal components. */
found = true;
break;
}
- extra_off += -lhs_ops[temj].off;
+ tem_extra_off += -lhs_ops[temj].off;
temj--;
}
}
--
2.51.0
