Checkpoint DOM VRP elimination before eliminating e->aux abuse.
* tree-vrp (find_conditional_asserts): Document missed
optimization opportunities due to use pruning.
(simplify_stmt_for_jump_threading): New.
(identify_jump_threads, finalize_jump_threads): New.
(vrp_finalize): Call identify_jump_threads.
(execute_vrp): Call finalize_jump_threads.10
* tree-ssa-dom.c: Remove all VRP related code.
(vrp_element, vrp_data, vrp_element_p, vrp_hash_elt): Kill.
(vrp_variables_stack, vrp_hash, vrp_eq, vrp_free): Kill.
(simplify_cond_and_lookup_avail_expr, record_range): Kill.
(extract_range_from_cond, thread_across_edge): Kill.
(tree_ssa_dominator_optimize): Do not set up or tream down VRP stuff.
(dom_opt_finalize_block): Similarly.
(record_equivalences_from_incoming_edge): Similarly.
(eliminate_redundant_computations): Similarly.
(simplify_stmt_for_jump_threading): New.
(dom_thread_across_edge): New.
(dom_opt_finalize_block): Simplify slightly using routines
from tree-ssa-threadedge.c
* loop-init.c: (loop_optimizer_finalize): Temporary hack to
work around checking failure due to abuse of e->aux.
* tree-flow.h (potentially_threadable_block): Prototype.
(thread_across_edge): Prototype.
* tree-ssa-threadedge.c: New, shared code for jump threading.
* Makefile.in (OBJS-common): Add tree-ssa-threadedge.o.
(tree-ssa-threadedge.o): Add dependencies.
* passes.c (init_optimization_passes): Merge PHIs before
VRP.
* testsuite/gcc.c-torture/execute/930529-1.x: Use -fwrapv.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/simplify-dom-branch@107316 138bc75d-0d04-0410-961f-82ee72b054a4