diff options
Diffstat (limited to 'gcc/dse.c')
| -rw-r--r-- | gcc/dse.c | 12 |
1 files changed, 6 insertions, 6 deletions
@@ -1445,7 +1445,7 @@ find_shift_sequence (int access_size, new_mode = GET_MODE_WIDER_MODE (new_mode)) { rtx target, new_reg, shift_seq, insn, new_lhs; - int cost, offset; + int cost; /* Try a wider mode if truncating the store mode to NEW_MODE requires a real instruction. */ @@ -1459,11 +1459,6 @@ find_shift_sequence (int access_size, if (!CONSTANT_P (store_info->rhs) && !MODES_TIEABLE_P (new_mode, store_mode)) continue; - offset = subreg_lowpart_offset (new_mode, store_mode); - new_lhs = simplify_gen_subreg (new_mode, copy_rtx (store_info->rhs), - store_mode, offset); - if (new_lhs == NULL_RTX) - continue; new_reg = gen_reg_rtx (new_mode); @@ -1496,6 +1491,11 @@ find_shift_sequence (int access_size, if (cost > COSTS_N_INSNS (1)) continue; + new_lhs = extract_low_bits (new_mode, store_mode, + copy_rtx (store_info->rhs)); + if (new_lhs == NULL_RTX) + continue; + /* We found an acceptable shift. Generate a move to take the value from the store and put it into the shift pseudo, then shift it, then generate another |