https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107240
Kewen Lin <linkw at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |linkw at gcc dot gnu.org
--- Comment #6 from Kewen Lin <linkw at gcc dot gnu.org> ---
The reason why it fails on power7 is that power7 misses the vector/vector shift
support for V2DImode (type vector(2) long unsigned int), the support querying
is for the gimple statement:
patt_25 = 5 << 28;
It's expected since vsld is supported till ISA 2.07 (power8) (Note that we have
vslb/vslh/vslw since ISA 2.03).
But you might have noticed that both shifted value and shifting count are
constants for this particular test case, so it doesn't need the actual
vector/vector shift target support here. One tiny enhancement as below can make
us not need to special case this for Power port.
diff --git a/gcc/tree-vect-patterns.cc b/gcc/tree-vect-patterns.cc
index 0cc315d3126..01d043a3d18 100644
--- a/gcc/tree-vect-patterns.cc
+++ b/gcc/tree-vect-patterns.cc
@@ -2115,9 +2115,10 @@ vect_recog_bit_insert_pattern (vec_info *vinfo,
stmt_vec_info stmt_info,
tree shifted = value;
if (shift_n)
{
+ tree shifted_value = fold_build2 (LSHIFT_EXPR, container_type, value,
shift);
pattern_stmt
= gimple_build_assign (vect_recog_temp_ssa_var (container_type),
- LSHIFT_EXPR, value, shift);
+ shifted_value);
append_pattern_def_seq (vinfo, stmt_info, pattern_stmt);
shifted = gimple_get_lhs (pattern_stmt);
}
