diff options
Diffstat (limited to 'gcc/cfgcleanup.c')
| -rw-r--r-- | gcc/cfgcleanup.c | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/gcc/cfgcleanup.c b/gcc/cfgcleanup.c index f40d2c1525b..51182e3f400 100644 --- a/gcc/cfgcleanup.c +++ b/gcc/cfgcleanup.c @@ -49,6 +49,7 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA #include "tm_p.h" #include "target.h" #include "regs.h" +#include "cfglayout.h" #include "expr.h" /* cleanup_cfg maintains following flags for each basic block. */ @@ -150,6 +151,15 @@ try_simplify_condjump (basic_block cbranch_block) return false; jump_dest_block = jump_block->succ->dest; + /* If we are partitioning hot/cold basic blocks, we don't want to + mess up unconditional or indirect jumps that cross between hot + and cold sections. */ + + if (flag_reorder_blocks_and_partition + && (jump_block->partition != jump_dest_block->partition + || cbranch_jump_edge->crossing_edge)) + return false; + /* The conditional branch must target the block after the unconditional branch. */ cbranch_dest_block = cbranch_jump_edge->dest; @@ -428,6 +438,14 @@ try_forward_edges (int mode, basic_block b) bool changed = false; edge e, next, *threaded_edges = NULL; + /* If we are partitioning hot/cold basic blocks, we don't want to + mess up unconditional or indirect jumps that cross between hot + and cold sections. */ + + if (flag_reorder_blocks_and_partition + && find_reg_note (BB_END (b), REG_CROSSING_JUMP, NULL_RTX)) + return false; + for (e = b->succ; e; e = next) { basic_block target, first; @@ -675,6 +693,15 @@ merge_blocks_move_predecessor_nojumps (basic_block a, basic_block b) { rtx barrier; + /* If we are partitioning hot/cold basic blocks, we don't want to + mess up unconditional or indirect jumps that cross between hot + and cold sections. */ + + if (flag_reorder_blocks_and_partition + && (a->partition != b->partition + || find_reg_note (BB_END (a), REG_CROSSING_JUMP, NULL_RTX))) + return; + barrier = next_nonnote_insn (BB_END (a)); if (GET_CODE (barrier) != BARRIER) abort (); @@ -718,6 +745,15 @@ merge_blocks_move_successor_nojumps (basic_block a, basic_block b) rtx barrier, real_b_end; rtx label, table; + /* If we are partitioning hot/cold basic blocks, we don't want to + mess up unconditional or indirect jumps that cross between hot + and cold sections. */ + + if (flag_reorder_blocks_and_partition + && (find_reg_note (BB_END (a), REG_CROSSING_JUMP, NULL_RTX) + || a->partition != b->partition)) + return; + real_b_end = BB_END (b); /* If there is a jump table following block B temporarily add the jump table @@ -782,6 +818,18 @@ merge_blocks_move (edge e, basic_block b, basic_block c, int mode) && tail_recursion_label_p (BB_HEAD (c))) return NULL; + /* If we are partitioning hot/cold basic blocks, we don't want to + mess up unconditional or indirect jumps that cross between hot + and cold sections. */ + + if (flag_reorder_blocks_and_partition + && (find_reg_note (BB_END (b), REG_CROSSING_JUMP, NULL_RTX) + || find_reg_note (BB_END (c), REG_CROSSING_JUMP, NULL_RTX) + || b->partition != c->partition)) + return NULL; + + + /* If B has a fallthru edge to C, no need to move anything. */ if (e->flags & EDGE_FALLTHRU) { @@ -1453,6 +1501,12 @@ try_crossjump_to_edge (int mode, edge e1, edge e2) rtx newpos1, newpos2; edge s; + /* If we have partitioned hot/cold basic blocks, it is a bad idea + to try this optimization. */ + + if (flag_reorder_blocks_and_partition && no_new_pseudos) + return false; + /* Search backward through forwarder blocks. We don't need to worry about multiple entry or chained forwarders, as they will be optimized away. We do this to look past the unconditional jump following a @@ -1639,6 +1693,15 @@ try_crossjump_bb (int mode, basic_block bb) if (!bb->pred || !bb->pred->pred_next) return false; + /* If we are partitioning hot/cold basic blocks, we don't want to + mess up unconditional or indirect jumps that cross between hot + and cold sections. */ + + if (flag_reorder_blocks_and_partition + && (bb->pred->src->partition != bb->pred->pred_next->src->partition + || bb->pred->crossing_edge)) + return false; + /* It is always cheapest to redirect a block that ends in a branch to a block that falls through into BB, as that adds no branches to the program. We'll try that combination first. */ @@ -1895,6 +1958,7 @@ try_optimize_cfg (int mode) && ! b->succ->succ_next && b->succ->dest != EXIT_BLOCK_PTR && onlyjump_p (BB_END (b)) + && !find_reg_note (BB_END (b), REG_CROSSING_JUMP, NULL_RTX) && try_redirect_by_replacing_jump (b->succ, b->succ->dest, (mode & CLEANUP_CFGLAYOUT) != 0)) { |