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| author | Jeff Law <law@redhat.com> | 2013-10-21 09:25:09 -0600 |
|---|---|---|
| committer | Jeff Law <law@gcc.gnu.org> | 2013-10-21 09:25:09 -0600 |
| commit | b5c4ff7888a8fc17c0ce047f539548dacf2c8f8d (patch) | |
| tree | 27dc71626562b27de9139558e8f1fc715449171e /gcc/tree-ssa-threadedge.c | |
| parent | ce0770fc7bb93ca051c0ccacbd98031f276a2b91 (diff) | |
| download | gcc-b5c4ff7888a8fc17c0ce047f539548dacf2c8f8d.zip gcc-b5c4ff7888a8fc17c0ce047f539548dacf2c8f8d.tar.gz gcc-b5c4ff7888a8fc17c0ce047f539548dacf2c8f8d.tar.bz2 | |
tree-ssa-threadedge.c (thread_through_normal_block): New argument VISITED.
* tree-ssa-threadedge.c (thread_through_normal_block): New argument VISITED.
Remove VISISTED as a local variable. When we have a threadable jump, verify
the destination of the jump has not been visised.
(thread_across_edge): Allocate VISITED bitmap once at function scope and
use it throughout. Make sure to set appropriate bits in VISITED for E (start
of jump thread path).
* tree-ssa-threadupdate.c (mark_threaded_blocks): Reject threading through
a joiner if any edge on the path has a recorded jump thread.
From-SVN: r203895
Diffstat (limited to 'gcc/tree-ssa-threadedge.c')
| -rw-r--r-- | gcc/tree-ssa-threadedge.c | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/gcc/tree-ssa-threadedge.c b/gcc/tree-ssa-threadedge.c index f567557..ebd93cb 100644 --- a/gcc/tree-ssa-threadedge.c +++ b/gcc/tree-ssa-threadedge.c @@ -883,7 +883,8 @@ thread_through_normal_block (edge e, bool handle_dominating_asserts, vec<tree> *stack, tree (*simplify) (gimple, gimple), - vec<jump_thread_edge *> *path) + vec<jump_thread_edge *> *path, + bitmap visited) { /* If E is a backedge, then we want to verify that the COND_EXPR, SWITCH_EXPR or GOTO_EXPR at the end of e->dest is not affected @@ -922,11 +923,10 @@ thread_through_normal_block (edge e, { edge taken_edge = find_taken_edge (e->dest, cond); basic_block dest = (taken_edge ? taken_edge->dest : NULL); - bitmap visited; /* DEST could be NULL for a computed jump to an absolute address. */ - if (dest == NULL || dest == e->dest) + if (dest == NULL || dest == e->dest || bitmap_bit_p (visited, dest->index)) return false; jump_thread_edge *x @@ -944,7 +944,6 @@ thread_through_normal_block (edge e, { /* We don't want to thread back to a block we have already visited. This may be overly conservative. */ - visited = BITMAP_ALLOC (NULL); bitmap_set_bit (visited, dest->index); bitmap_set_bit (visited, e->dest->index); thread_around_empty_blocks (taken_edge, @@ -953,7 +952,6 @@ thread_through_normal_block (edge e, simplify, visited, path); - BITMAP_FREE (visited); } return true; } @@ -995,15 +993,21 @@ thread_across_edge (gimple dummy_cond, vec<tree> *stack, tree (*simplify) (gimple, gimple)) { + bitmap visited = BITMAP_ALLOC (NULL); + stmt_count = 0; vec<jump_thread_edge *> *path = new vec<jump_thread_edge *> (); + bitmap_clear (visited); + bitmap_set_bit (visited, e->src->index); + bitmap_set_bit (visited, e->dest->index); if (thread_through_normal_block (e, dummy_cond, handle_dominating_asserts, - stack, simplify, path)) + stack, simplify, path, visited)) { propagate_threaded_block_debug_into (path->last ()->e->dest, e->dest); remove_temporary_equivalences (stack); + BITMAP_FREE (visited); register_jump_thread (path); return; } @@ -1030,7 +1034,6 @@ thread_across_edge (gimple dummy_cond, edge taken_edge; edge_iterator ei; bool found; - bitmap visited = BITMAP_ALLOC (NULL); /* Look at each successor of E->dest to see if we can thread through it. */ FOR_EACH_EDGE (taken_edge, ei, e->dest->succs) |