https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77937 reports an ICE in SLSR
where a POINTER_PLUS_EXPR occurs with a candidate increment of -1. This
is supposed to be prevented by code in analyze_increments, since replacement
of such a candidate is not guaranteed to be profitable. The test for this
was inadequate. This patch replaces it with the correct check, determining
whether the type of the candidate is a pointer type.
Bootstrapped and tested on powerpc64le-unknown-linux-gnu, committed.
Thanks,
Bill
2016-10-12 Bill Schmidt <wschm...@linux.vnet.ibm.com>
PR tree-optimization/77937
* gimple-ssa-strength-reduction.c (analyze_increments): Use
POINTER_TYPE_P on the candidate type to determine whether
candidates in this chain require pointer arithmetic.
Index: gcc/gimple-ssa-strength-reduction.c
===================================================================
--- gcc/gimple-ssa-strength-reduction.c (revision 240946)
+++ gcc/gimple-ssa-strength-reduction.c (working copy)
@@ -2816,8 +2816,7 @@ analyze_increments (slsr_cand_t first_dep, machine
else if (incr == 0
|| incr == 1
|| (incr == -1
- && (gimple_assign_rhs_code (first_dep->cand_stmt)
- != POINTER_PLUS_EXPR)))
+ && !POINTER_TYPE_P (first_dep->cand_type)))
incr_vec[i].cost = COST_NEUTRAL;
/* FORNOW: If we need to add an initializer, give up if a cast from
