diff options
Diffstat (limited to 'gcc/tree-ssa-threadbackward.c')
| -rw-r--r-- | gcc/tree-ssa-threadbackward.c | 26 |
1 files changed, 19 insertions, 7 deletions
diff --git a/gcc/tree-ssa-threadbackward.c b/gcc/tree-ssa-threadbackward.c index 139d376..9dd37ad 100644 --- a/gcc/tree-ssa-threadbackward.c +++ b/gcc/tree-ssa-threadbackward.c @@ -378,7 +378,7 @@ profitable_jump_thread_path (vec<basic_block, va_gc> *&path, register the path. */ static void -convert_and_register_jump_thread_path (vec<basic_block, va_gc> *&path, +convert_and_register_jump_thread_path (vec<basic_block, va_gc> *path, edge taken_edge) { vec<jump_thread_edge *> *jump_thread_path = new vec<jump_thread_edge *> (); @@ -402,9 +402,6 @@ convert_and_register_jump_thread_path (vec<basic_block, va_gc> *&path, register_jump_thread (jump_thread_path); --max_threaded_paths; - - /* Remove BBI from the path. */ - path->pop (); } /* We trace the value of the SSA_NAME NAME back through any phi nodes looking @@ -459,6 +456,9 @@ fsm_find_control_statement_thread_paths (tree name, seen_loop_phi = true; } + if (bb_loop_depth (last_bb_in_path) > bb_loop_depth (var_bb)) + return; + /* Following the chain of SSA_NAME definitions, we jumped from a definition in LAST_BB_IN_PATH to a definition in VAR_BB. When these basic blocks are different, append to PATH the blocks from LAST_BB_IN_PATH to VAR_BB. */ @@ -505,7 +505,9 @@ fsm_find_control_statement_thread_paths (tree name, NEXT_PATH. Don't add them here to avoid pollution. */ for (unsigned int i = 0; i < next_path->length () - 1; i++) { - if (visited_bbs->contains ((*next_path)[i])) + if (visited_bbs->contains ((*next_path)[i]) + || (bb_loop_depth (last_bb_in_path) + > bb_loop_depth ((*next_path)[i]))) { vec_free (next_path); return; @@ -557,7 +559,12 @@ fsm_find_control_statement_thread_paths (tree name, into the canonical form and register it. */ edge taken_edge = profitable_jump_thread_path (path, bbi, name, arg); if (taken_edge) - convert_and_register_jump_thread_path (path, taken_edge); + { + if (bb_loop_depth (taken_edge->src) + >= bb_loop_depth (taken_edge->dest)) + convert_and_register_jump_thread_path (path, taken_edge); + path->pop (); + } } } else if (gimple_code (def_stmt) == GIMPLE_ASSIGN) @@ -578,7 +585,12 @@ fsm_find_control_statement_thread_paths (tree name, edge taken_edge = profitable_jump_thread_path (path, var_bb, name, arg); if (taken_edge) - convert_and_register_jump_thread_path (path, taken_edge); + { + if (bb_loop_depth (taken_edge->src) + >= bb_loop_depth (taken_edge->dest)) + convert_and_register_jump_thread_path (path, taken_edge); + path->pop (); + } /* And put the current block back onto the path so that the state of the stack is unchanged when we leave. */ |