diff options
Diffstat (limited to 'gcc/tree-vrp.c')
| -rw-r--r-- | gcc/tree-vrp.c | 600 |
1 files changed, 6 insertions, 594 deletions
diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c index 7173ab2..6fae6b2 100644 --- a/gcc/tree-vrp.c +++ b/gcc/tree-vrp.c @@ -66,8 +66,6 @@ along with GCC; see the file COPYING3. If not see #include "attribs.h" #include "vr-values.h" -#define VR_INITIALIZER { VR_UNDEFINED, NULL_TREE, NULL_TREE, NULL } - /* Set of SSA names found live during the RPO traversal of the function for still active basic-blocks. */ static sbitmap *live; @@ -85,21 +83,6 @@ live_on_edge (edge e, tree name) static int compare_values (tree val1, tree val2); static int compare_values_warnv (tree val1, tree val2, bool *); -struct assert_info -{ - /* Predicate code for the ASSERT_EXPR. Must be COMPARISON_CLASS_P. */ - enum tree_code comp_code; - - /* Name to register the assert for. */ - tree name; - - /* Value being compared against. */ - tree val; - - /* Expression to compare. */ - tree expr; -}; - /* Location information for ASSERT_EXPRs. Each instance of this structure describes an ASSERT_EXPR for an SSA name. Since a single SSA name may have more than one assertion associated with it, these @@ -207,10 +190,9 @@ set_value_range_to_undefined (value_range *vr) bitmap_clear (vr->equiv); } - /* Set value range VR to VR_VARYING. */ -static inline void +void set_value_range_to_varying (value_range *vr) { vr->type = VR_VARYING; @@ -219,7 +201,6 @@ set_value_range_to_varying (value_range *vr) bitmap_clear (vr->equiv); } - /* Set value range VR to {T, MIN, MAX, EQUIV}. */ static void @@ -582,7 +563,7 @@ vr_values::set_defs_to_varying (gimple *stmt) /* Return true, if VAL1 and VAL2 are equal values for VRP purposes. */ -static inline bool +bool vrp_operand_equal_p (const_tree val1, const_tree val2) { if (val1 == val2) @@ -1201,7 +1182,7 @@ value_ranges_intersect_p (value_range *vr0, value_range *vr1) /* Return 1 if [MIN, MAX] includes the value zero, 0 if it does not include the value zero, -2 if we cannot tell. */ -static inline int +int range_includes_zero_p (tree min, tree max) { tree zero = build_int_cst (TREE_TYPE (min), 0); @@ -4524,7 +4505,7 @@ fp_predicate (gimple *stmt) describes the inferred range. Return true if a range could be inferred. */ -static bool +bool infer_value_range (gimple *stmt, tree op, tree_code *comp_code_p, tree *val_p) { *val_p = NULL_TREE; @@ -5696,7 +5677,7 @@ is_masked_range_test (tree name, tree valt, enum tree_code cond_code, the condition COND contributing to the conditional jump pointed to by SI. */ -static void +void register_edge_assert_for (tree name, edge e, enum tree_code cond_code, tree cond_op0, tree cond_op1, vec<assert_info> &asserts) @@ -7072,7 +7053,7 @@ remove_range_assertions (void) /* Return true if STMT is interesting for VRP. */ -static bool +bool stmt_interesting_for_vrp (gimple *stmt) { if (gimple_code (stmt) == GIMPLE_PHI) @@ -10920,423 +10901,6 @@ vrp_prop::vrp_finalize (bool warn_array_bounds_p) check_all_array_refs (); } -/* evrp_dom_walker visits the basic blocks in the dominance order and set - the Value Ranges (VR) for SSA_NAMEs in the scope. Use this VR to - discover more VRs. */ - -class evrp_dom_walker : public dom_walker -{ -public: - evrp_dom_walker () - : dom_walker (CDI_DOMINATORS), stack (10) - { - need_eh_cleanup = BITMAP_ALLOC (NULL); - } - ~evrp_dom_walker () - { - BITMAP_FREE (need_eh_cleanup); - } - virtual edge before_dom_children (basic_block); - virtual void after_dom_children (basic_block); - void push_value_range (tree var, value_range *vr); - value_range *pop_value_range (tree var); - value_range *try_find_new_range (tree, tree op, tree_code code, tree limit); - - /* Cond_stack holds the old VR. */ - auto_vec<std::pair <tree, value_range*> > stack; - bitmap need_eh_cleanup; - auto_vec<gimple *> stmts_to_fixup; - auto_vec<gimple *> stmts_to_remove; - - class vr_values vr_values; - - /* Temporary delegators. */ - value_range *get_value_range (const_tree op) - { return vr_values.get_value_range (op); } - bool update_value_range (const_tree op, value_range *vr) - { return vr_values.update_value_range (op, vr); } - void extract_range_from_phi_node (gphi *phi, value_range *vr) - { vr_values.extract_range_from_phi_node (phi, vr); } - void extract_range_for_var_from_comparison_expr (tree var, - enum tree_code cond_code, - tree op, tree limit, - value_range *vr_p) - { vr_values.extract_range_for_var_from_comparison_expr (var, cond_code, - op, limit, vr_p); } - void adjust_range_with_scev (value_range *vr, struct loop *loop, - gimple *stmt, tree var) - { vr_values.adjust_range_with_scev (vr, loop, stmt, var); } - tree op_with_constant_singleton_value_range (tree op) - { return vr_values.op_with_constant_singleton_value_range (op); } - void extract_range_from_stmt (gimple *stmt, edge *taken_edge_p, - tree *output_p, value_range *vr) - { vr_values.extract_range_from_stmt (stmt, taken_edge_p, output_p, vr); } - void set_defs_to_varying (gimple *stmt) - { return vr_values.set_defs_to_varying (stmt); } - void set_vr_value (tree name, value_range *vr) - { vr_values.set_vr_value (name, vr); } - void simplify_cond_using_ranges_2 (gcond *stmt) - { vr_values.simplify_cond_using_ranges_2 (stmt); } - void vrp_visit_cond_stmt (gcond *cond, edge *e) - { vr_values.vrp_visit_cond_stmt (cond, e); } -}; - -/* Find new range for NAME such that (OP CODE LIMIT) is true. */ - -value_range * -evrp_dom_walker::try_find_new_range (tree name, - tree op, tree_code code, tree limit) -{ - value_range vr = VR_INITIALIZER; - value_range *old_vr = get_value_range (name); - - /* Discover VR when condition is true. */ - extract_range_for_var_from_comparison_expr (name, code, op, - limit, &vr); - /* If we found any usable VR, set the VR to ssa_name and create a - PUSH old value in the stack with the old VR. */ - if (vr.type == VR_RANGE || vr.type == VR_ANTI_RANGE) - { - if (old_vr->type == vr.type - && vrp_operand_equal_p (old_vr->min, vr.min) - && vrp_operand_equal_p (old_vr->max, vr.max)) - return NULL; - value_range *new_vr = vr_values.vrp_value_range_pool.allocate (); - *new_vr = vr; - return new_vr; - } - return NULL; -} - -/* See if there is any new scope is entered with new VR and set that VR to - ssa_name before visiting the statements in the scope. */ - -edge -evrp_dom_walker::before_dom_children (basic_block bb) -{ - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "Visiting BB%d\n", bb->index); - - stack.safe_push (std::make_pair (NULL_TREE, (value_range *)NULL)); - - edge pred_e = single_pred_edge_ignoring_loop_edges (bb, false); - if (pred_e) - { - gimple *stmt = last_stmt (pred_e->src); - tree op0 = NULL_TREE; - - if (stmt - && gimple_code (stmt) == GIMPLE_COND - && (op0 = gimple_cond_lhs (stmt)) - && TREE_CODE (op0) == SSA_NAME - && (INTEGRAL_TYPE_P (TREE_TYPE (gimple_cond_lhs (stmt))) - || POINTER_TYPE_P (TREE_TYPE (gimple_cond_lhs (stmt))))) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "Visiting controlling predicate "); - print_gimple_stmt (dump_file, stmt, 0); - } - /* Entering a new scope. Try to see if we can find a VR - here. */ - tree op1 = gimple_cond_rhs (stmt); - if (TREE_OVERFLOW_P (op1)) - op1 = drop_tree_overflow (op1); - tree_code code = gimple_cond_code (stmt); - - auto_vec<assert_info, 8> asserts; - register_edge_assert_for (op0, pred_e, code, op0, op1, asserts); - if (TREE_CODE (op1) == SSA_NAME) - register_edge_assert_for (op1, pred_e, code, op0, op1, asserts); - - auto_vec<std::pair<tree, value_range *>, 8> vrs; - for (unsigned i = 0; i < asserts.length (); ++i) - { - value_range *vr = try_find_new_range (asserts[i].name, - asserts[i].expr, - asserts[i].comp_code, - asserts[i].val); - if (vr) - vrs.safe_push (std::make_pair (asserts[i].name, vr)); - } - /* Push updated ranges only after finding all of them to avoid - ordering issues that can lead to worse ranges. */ - for (unsigned i = 0; i < vrs.length (); ++i) - push_value_range (vrs[i].first, vrs[i].second); - } - } - - /* Visit PHI stmts and discover any new VRs possible. */ - bool has_unvisited_preds = false; - edge_iterator ei; - edge e; - FOR_EACH_EDGE (e, ei, bb->preds) - if (e->flags & EDGE_EXECUTABLE - && !(e->src->flags & BB_VISITED)) - { - has_unvisited_preds = true; - break; - } - - for (gphi_iterator gpi = gsi_start_phis (bb); - !gsi_end_p (gpi); gsi_next (&gpi)) - { - gphi *phi = gpi.phi (); - tree lhs = PHI_RESULT (phi); - if (virtual_operand_p (lhs)) - continue; - value_range vr_result = VR_INITIALIZER; - bool interesting = stmt_interesting_for_vrp (phi); - if (interesting && dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "Visiting PHI node "); - print_gimple_stmt (dump_file, phi, 0); - } - if (!has_unvisited_preds - && interesting) - extract_range_from_phi_node (phi, &vr_result); - else - { - set_value_range_to_varying (&vr_result); - /* When we have an unvisited executable predecessor we can't - use PHI arg ranges which may be still UNDEFINED but have - to use VARYING for them. But we can still resort to - SCEV for loop header PHIs. */ - struct loop *l; - if (interesting - && (l = loop_containing_stmt (phi)) - && l->header == gimple_bb (phi)) - adjust_range_with_scev (&vr_result, l, phi, lhs); - } - update_value_range (lhs, &vr_result); - - /* Mark PHIs whose lhs we fully propagate for removal. */ - tree val = op_with_constant_singleton_value_range (lhs); - if (val && may_propagate_copy (lhs, val)) - { - stmts_to_remove.safe_push (phi); - continue; - } - - /* Set the SSA with the value range. */ - if (INTEGRAL_TYPE_P (TREE_TYPE (lhs))) - { - if ((vr_result.type == VR_RANGE - || vr_result.type == VR_ANTI_RANGE) - && (TREE_CODE (vr_result.min) == INTEGER_CST) - && (TREE_CODE (vr_result.max) == INTEGER_CST)) - set_range_info (lhs, vr_result.type, - wi::to_wide (vr_result.min), - wi::to_wide (vr_result.max)); - } - else if (POINTER_TYPE_P (TREE_TYPE (lhs)) - && ((vr_result.type == VR_RANGE - && range_includes_zero_p (vr_result.min, - vr_result.max) == 0) - || (vr_result.type == VR_ANTI_RANGE - && range_includes_zero_p (vr_result.min, - vr_result.max) == 1))) - set_ptr_nonnull (lhs); - } - - edge taken_edge = NULL; - - /* Visit all other stmts and discover any new VRs possible. */ - for (gimple_stmt_iterator gsi = gsi_start_bb (bb); - !gsi_end_p (gsi); gsi_next (&gsi)) - { - gimple *stmt = gsi_stmt (gsi); - tree output = NULL_TREE; - gimple *old_stmt = stmt; - bool was_noreturn = (is_gimple_call (stmt) - && gimple_call_noreturn_p (stmt)); - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "Visiting stmt "); - print_gimple_stmt (dump_file, stmt, 0); - } - - if (gcond *cond = dyn_cast <gcond *> (stmt)) - { - vrp_visit_cond_stmt (cond, &taken_edge); - if (taken_edge) - { - if (taken_edge->flags & EDGE_TRUE_VALUE) - gimple_cond_make_true (cond); - else if (taken_edge->flags & EDGE_FALSE_VALUE) - gimple_cond_make_false (cond); - else - gcc_unreachable (); - update_stmt (stmt); - } - } - else if (stmt_interesting_for_vrp (stmt)) - { - edge taken_edge; - value_range vr = VR_INITIALIZER; - extract_range_from_stmt (stmt, &taken_edge, &output, &vr); - if (output - && (vr.type == VR_RANGE || vr.type == VR_ANTI_RANGE)) - { - update_value_range (output, &vr); - vr = *get_value_range (output); - - /* Mark stmts whose output we fully propagate for removal. */ - tree val; - if ((val = op_with_constant_singleton_value_range (output)) - && may_propagate_copy (output, val) - && !stmt_could_throw_p (stmt) - && !gimple_has_side_effects (stmt)) - { - stmts_to_remove.safe_push (stmt); - continue; - } - - /* Set the SSA with the value range. */ - if (INTEGRAL_TYPE_P (TREE_TYPE (output))) - { - if ((vr.type == VR_RANGE - || vr.type == VR_ANTI_RANGE) - && (TREE_CODE (vr.min) == INTEGER_CST) - && (TREE_CODE (vr.max) == INTEGER_CST)) - set_range_info (output, vr.type, - wi::to_wide (vr.min), - wi::to_wide (vr.max)); - } - else if (POINTER_TYPE_P (TREE_TYPE (output)) - && ((vr.type == VR_RANGE - && range_includes_zero_p (vr.min, - vr.max) == 0) - || (vr.type == VR_ANTI_RANGE - && range_includes_zero_p (vr.min, - vr.max) == 1))) - set_ptr_nonnull (output); - } - else - set_defs_to_varying (stmt); - } - else - set_defs_to_varying (stmt); - - /* See if we can derive a range for any of STMT's operands. */ - tree op; - ssa_op_iter i; - FOR_EACH_SSA_TREE_OPERAND (op, stmt, i, SSA_OP_USE) - { - tree value; - enum tree_code comp_code; - - /* If OP is used in such a way that we can infer a value - range for it, and we don't find a previous assertion for - it, create a new assertion location node for OP. */ - if (infer_value_range (stmt, op, &comp_code, &value)) - { - /* If we are able to infer a nonzero value range for OP, - then walk backwards through the use-def chain to see if OP - was set via a typecast. - If so, then we can also infer a nonzero value range - for the operand of the NOP_EXPR. */ - if (comp_code == NE_EXPR && integer_zerop (value)) - { - tree t = op; - gimple *def_stmt = SSA_NAME_DEF_STMT (t); - while (is_gimple_assign (def_stmt) - && CONVERT_EXPR_CODE_P - (gimple_assign_rhs_code (def_stmt)) - && TREE_CODE - (gimple_assign_rhs1 (def_stmt)) == SSA_NAME - && POINTER_TYPE_P - (TREE_TYPE (gimple_assign_rhs1 (def_stmt)))) - { - t = gimple_assign_rhs1 (def_stmt); - def_stmt = SSA_NAME_DEF_STMT (t); - - /* Add VR when (T COMP_CODE value) condition is - true. */ - value_range *op_range - = try_find_new_range (t, t, comp_code, value); - if (op_range) - push_value_range (t, op_range); - } - } - /* Add VR when (OP COMP_CODE value) condition is true. */ - value_range *op_range = try_find_new_range (op, op, - comp_code, value); - if (op_range) - push_value_range (op, op_range); - } - } - - /* Try folding stmts with the VR discovered. */ - class vrp_folder vrp_folder; - vrp_folder.vr_values = &vr_values; - bool did_replace = vrp_folder.replace_uses_in (stmt); - if (fold_stmt (&gsi, follow_single_use_edges) - || did_replace) - { - stmt = gsi_stmt (gsi); - update_stmt (stmt); - did_replace = true; - } - - if (did_replace) - { - /* If we cleaned up EH information from the statement, - remove EH edges. */ - if (maybe_clean_or_replace_eh_stmt (old_stmt, stmt)) - bitmap_set_bit (need_eh_cleanup, bb->index); - - /* If we turned a not noreturn call into a noreturn one - schedule it for fixup. */ - if (!was_noreturn - && is_gimple_call (stmt) - && gimple_call_noreturn_p (stmt)) - stmts_to_fixup.safe_push (stmt); - - if (gimple_assign_single_p (stmt)) - { - tree rhs = gimple_assign_rhs1 (stmt); - if (TREE_CODE (rhs) == ADDR_EXPR) - recompute_tree_invariant_for_addr_expr (rhs); - } - } - } - - /* Visit BB successor PHI nodes and replace PHI args. */ - FOR_EACH_EDGE (e, ei, bb->succs) - { - for (gphi_iterator gpi = gsi_start_phis (e->dest); - !gsi_end_p (gpi); gsi_next (&gpi)) - { - gphi *phi = gpi.phi (); - use_operand_p use_p = PHI_ARG_DEF_PTR_FROM_EDGE (phi, e); - tree arg = USE_FROM_PTR (use_p); - if (TREE_CODE (arg) != SSA_NAME - || virtual_operand_p (arg)) - continue; - tree val = op_with_constant_singleton_value_range (arg); - if (val && may_propagate_copy (arg, val)) - propagate_value (use_p, val); - } - } - - bb->flags |= BB_VISITED; - - return taken_edge; -} - -/* Restore/pop VRs valid only for BB when we leave BB. */ - -void -evrp_dom_walker::after_dom_children (basic_block bb ATTRIBUTE_UNUSED) -{ - gcc_checking_assert (!stack.is_empty ()); - while (stack.last ().first != NULL_TREE) - pop_value_range (stack.last ().first); - stack.pop (); -} - void vr_values::set_vr_value (tree var, value_range *vr) { @@ -11345,117 +10909,6 @@ vr_values::set_vr_value (tree var, value_range *vr) vr_value[SSA_NAME_VERSION (var)] = vr; } -/* Push the Value Range of VAR to the stack and update it with new VR. */ - -void -evrp_dom_walker::push_value_range (tree var, value_range *vr) -{ - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "pushing new range for "); - print_generic_expr (dump_file, var); - fprintf (dump_file, ": "); - dump_value_range (dump_file, vr); - fprintf (dump_file, "\n"); - } - stack.safe_push (std::make_pair (var, get_value_range (var))); - set_vr_value (var, vr); -} - -/* Pop the Value Range from the vrp_stack and update VAR with it. */ - -value_range * -evrp_dom_walker::pop_value_range (tree var) -{ - value_range *vr = stack.last ().second; - gcc_checking_assert (var == stack.last ().first); - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "popping range for "); - print_generic_expr (dump_file, var); - fprintf (dump_file, ", restoring "); - dump_value_range (dump_file, vr); - fprintf (dump_file, "\n"); - } - set_vr_value (var, vr); - stack.pop (); - return vr; -} - - -/* Main entry point for the early vrp pass which is a simplified non-iterative - version of vrp where basic blocks are visited in dominance order. Value - ranges discovered in early vrp will also be used by ipa-vrp. */ - -static unsigned int -execute_early_vrp () -{ - edge e; - edge_iterator ei; - basic_block bb; - - loop_optimizer_init (LOOPS_NORMAL | LOOPS_HAVE_RECORDED_EXITS); - rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa); - scev_initialize (); - calculate_dominance_info (CDI_DOMINATORS); - FOR_EACH_BB_FN (bb, cfun) - { - bb->flags &= ~BB_VISITED; - FOR_EACH_EDGE (e, ei, bb->preds) - e->flags |= EDGE_EXECUTABLE; - } - - /* Walk stmts in dominance order and propagate VRP. */ - evrp_dom_walker walker; - walker.walk (ENTRY_BLOCK_PTR_FOR_FN (cfun)); - - if (dump_file) - { - fprintf (dump_file, "\nValue ranges after Early VRP:\n\n"); - walker.vr_values.dump_all_value_ranges (dump_file); - fprintf (dump_file, "\n"); - } - - /* Remove stmts in reverse order to make debug stmt creation possible. */ - while (! walker.stmts_to_remove.is_empty ()) - { - gimple *stmt = walker.stmts_to_remove.pop (); - if (dump_file && dump_flags & TDF_DETAILS) - { - fprintf (dump_file, "Removing dead stmt "); - print_gimple_stmt (dump_file, stmt, 0); - fprintf (dump_file, "\n"); - } - gimple_stmt_iterator gsi = gsi_for_stmt (stmt); - if (gimple_code (stmt) == GIMPLE_PHI) - remove_phi_node (&gsi, true); - else - { - unlink_stmt_vdef (stmt); - gsi_remove (&gsi, true); - release_defs (stmt); - } - } - - if (!bitmap_empty_p (walker.need_eh_cleanup)) - gimple_purge_all_dead_eh_edges (walker.need_eh_cleanup); - - /* Fixup stmts that became noreturn calls. This may require splitting - blocks and thus isn't possible during the dominator walk. Do this - in reverse order so we don't inadvertedly remove a stmt we want to - fixup by visiting a dominating now noreturn call first. */ - while (!walker.stmts_to_fixup.is_empty ()) - { - gimple *stmt = walker.stmts_to_fixup.pop (); - fixup_noreturn_call (stmt); - } - - scev_finalize (); - loop_optimizer_finalize (); - return 0; -} - - /* Main entry point to VRP (Value Range Propagation). This pass is loosely based on J. R. C. Patterson, ``Accurate Static Branch Prediction by Value Range Propagation,'' in SIGPLAN Conference on @@ -11649,44 +11102,3 @@ make_pass_vrp (gcc::context *ctxt) { return new pass_vrp (ctxt); } - -namespace { - -const pass_data pass_data_early_vrp = -{ - GIMPLE_PASS, /* type */ - "evrp", /* name */ - OPTGROUP_NONE, /* optinfo_flags */ - TV_TREE_EARLY_VRP, /* tv_id */ - PROP_ssa, /* properties_required */ - 0, /* properties_provided */ - 0, /* properties_destroyed */ - 0, /* todo_flags_start */ - ( TODO_cleanup_cfg | TODO_update_ssa | TODO_verify_all ), -}; - -class pass_early_vrp : public gimple_opt_pass -{ -public: - pass_early_vrp (gcc::context *ctxt) - : gimple_opt_pass (pass_data_early_vrp, ctxt) - {} - - /* opt_pass methods: */ - opt_pass * clone () { return new pass_early_vrp (m_ctxt); } - virtual bool gate (function *) - { - return flag_tree_vrp != 0; - } - virtual unsigned int execute (function *) - { return execute_early_vrp (); } - -}; // class pass_vrp -} // anon namespace - -gimple_opt_pass * -make_pass_early_vrp (gcc::context *ctxt) -{ - return new pass_early_vrp (ctxt); -} - |