diff options
Diffstat (limited to 'gcc/loop.c')
| -rw-r--r-- | gcc/loop.c | 18 |
1 files changed, 12 insertions, 6 deletions
@@ -5677,19 +5677,25 @@ check_final_value (loop, v) if (GET_CODE (p) == INSN || GET_CODE (p) == JUMP_INSN || GET_CODE (p) == CALL_INSN) { - if (biv_increment_seen) + /* It is possible for the BIV increment to use the GIV if we + have a cycle. Thus we must be sure to check each insn for + both BIV and GIV uses, and we must check for BIV uses + first. */ + + if (! biv_increment_seen + && reg_set_p (v->src_reg, PATTERN (p))) + biv_increment_seen = 1; + + if (reg_mentioned_p (v->dest_reg, PATTERN (p))) { - if (reg_mentioned_p (v->dest_reg, PATTERN (p))) + if (biv_increment_seen) { v->replaceable = 0; v->not_replaceable = 1; break; } + last_giv_use = p; } - else if (reg_set_p (v->src_reg, PATTERN (p))) - biv_increment_seen = 1; - else if (reg_mentioned_p (v->dest_reg, PATTERN (p))) - last_giv_use = p; } } |