diff options
Diffstat (limited to 'gcc/cfgrtl.c')
| -rw-r--r-- | gcc/cfgrtl.c | 29 |
1 files changed, 20 insertions, 9 deletions
diff --git a/gcc/cfgrtl.c b/gcc/cfgrtl.c index 1b578d7feeb..b58562fcc5f 100644 --- a/gcc/cfgrtl.c +++ b/gcc/cfgrtl.c @@ -541,10 +541,9 @@ flow_active_insn_p (const_rtx insn) /* Return true if the block has no effect and only forwards control flow to its single destination. */ -/* FIXME: Make this a cfg hook. */ bool -forwarder_block_p (const_basic_block bb) +contains_no_active_insn_p (const_basic_block bb) { rtx insn; @@ -552,6 +551,24 @@ forwarder_block_p (const_basic_block bb) || !single_succ_p (bb)) return false; + for (insn = BB_HEAD (bb); insn != BB_END (bb); insn = NEXT_INSN (insn)) + if (INSN_P (insn) && flow_active_insn_p (insn)) + return false; + + return (!INSN_P (insn) + || (JUMP_P (insn) && simplejump_p (insn)) + || !flow_active_insn_p (insn)); +} + +/* Likewise, but protect loop latches, headers and preheaders. */ +/* FIXME: Make this a cfg hook. */ + +bool +forwarder_block_p (const_basic_block bb) +{ + if (!contains_no_active_insn_p (bb)) + return false; + /* Protect loop latches, headers and preheaders. */ if (current_loops) { @@ -563,13 +580,7 @@ forwarder_block_p (const_basic_block bb) return false; } - for (insn = BB_HEAD (bb); insn != BB_END (bb); insn = NEXT_INSN (insn)) - if (INSN_P (insn) && flow_active_insn_p (insn)) - return false; - - return (!INSN_P (insn) - || (JUMP_P (insn) && simplejump_p (insn)) - || !flow_active_insn_p (insn)); + return true; } /* Return nonzero if we can reach target from src by falling through. */ |