diff options
Diffstat (limited to 'gcc/unroll.c')
| -rw-r--r-- | gcc/unroll.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/gcc/unroll.c b/gcc/unroll.c index c0fe373fdfb..a2af2137f05 100644 --- a/gcc/unroll.c +++ b/gcc/unroll.c @@ -3519,6 +3519,27 @@ loop_iterations (loop) return 0; } + /* If there are multiple conditionalized loop exit tests, they may jump + back to differing CODE_LABELs. */ + if (loop->top && loop->cont) + { + rtx temp = PREV_INSN (last_loop_insn); + + do + { + if (GET_CODE (temp) == JUMP_INSN + && INSN_LUID (JUMP_LABEL (temp)) > INSN_LUID (loop->top) + && INSN_LUID (JUMP_LABEL (temp)) < INSN_LUID (loop->cont)) + { + if (loop_dump_stream) + fprintf (loop_dump_stream, + "Loop iterations: Loop has multiple back edges.\n"); + return 0; + } + } + while ((temp = PREV_INSN (temp)) != loop->cont); + } + /* Find the iteration variable. If the last insn is a conditional branch, and the insn before tests a register value, make that the iteration variable. */ |