61 uint _loop_flags;
62 // Names for flag bitfields
63 enum { Normal=0, Pre=1, Main=2, Post=3, PreMainPostFlagsMask=3,
64 MainHasNoPreLoop = 1<<2,
65 HasExactTripCount = 1<<3,
66 InnerLoop = 1<<4,
67 PartialPeelLoop = 1<<5,
68 PartialPeelFailed = 1<<6,
69 HasReductions = 1<<7,
70 WasSlpAnalyzed = 1<<8,
71 PassedSlpAnalysis = 1<<9,
72 DoUnrollOnly = 1<<10,
73 VectorizedLoop = 1<<11,
74 HasAtomicPostLoop = 1<<12,
75 HasRangeChecks = 1<<13,
76 IsMultiversioned = 1<<14,
77 StripMined = 1<<15,
78 SubwordLoop = 1<<16,
79 ProfileTripFailed = 1<<17,
80 TransformedLongInnerLoop = 1<<18,
81 TransformedLongOuterLoop = 1<<19};
82 char _unswitch_count;
83 enum { _unswitch_max=3 };
84 char _postloop_flags;
85 enum { LoopNotRCEChecked = 0, LoopRCEChecked = 1, RCEPostLoop = 2 };
86
87 // Expected trip count from profile data
88 float _profile_trip_cnt;
89
90 public:
91 // Names for edge indices
92 enum { Self=0, EntryControl, LoopBackControl };
93
94 bool is_inner_loop() const { return _loop_flags & InnerLoop; }
95 void set_inner_loop() { _loop_flags |= InnerLoop; }
96
97 bool range_checks_present() const { return _loop_flags & HasRangeChecks; }
98 bool is_multiversioned() const { return _loop_flags & IsMultiversioned; }
99 bool is_vectorized_loop() const { return _loop_flags & VectorizedLoop; }
100 bool is_partial_peel_loop() const { return _loop_flags & PartialPeelLoop; }
101 void set_partial_peel_loop() { _loop_flags |= PartialPeelLoop; }
102 bool partial_peel_has_failed() const { return _loop_flags & PartialPeelFailed; }
103 bool is_strip_mined() const { return _loop_flags & StripMined; }
104 bool is_profile_trip_failed() const { return _loop_flags & ProfileTripFailed; }
105 bool is_subword_loop() const { return _loop_flags & SubwordLoop; }
106 bool is_transformed_long_inner_loop() const { return _loop_flags & TransformedLongInnerLoop; }
107 bool is_transformed_long_outer_loop() const { return _loop_flags & TransformedLongOuterLoop; }
108
109 void mark_partial_peel_failed() { _loop_flags |= PartialPeelFailed; }
110 void mark_has_reductions() { _loop_flags |= HasReductions; }
111 void mark_was_slp() { _loop_flags |= WasSlpAnalyzed; }
112 void mark_passed_slp() { _loop_flags |= PassedSlpAnalysis; }
113 void mark_do_unroll_only() { _loop_flags |= DoUnrollOnly; }
114 void mark_loop_vectorized() { _loop_flags |= VectorizedLoop; }
115 void mark_has_atomic_post_loop() { _loop_flags |= HasAtomicPostLoop; }
116 void mark_has_range_checks() { _loop_flags |= HasRangeChecks; }
117 void mark_is_multiversioned() { _loop_flags |= IsMultiversioned; }
118 void mark_strip_mined() { _loop_flags |= StripMined; }
119 void clear_strip_mined() { _loop_flags &= ~StripMined; }
120 void mark_profile_trip_failed() { _loop_flags |= ProfileTripFailed; }
121 void mark_subword_loop() { _loop_flags |= SubwordLoop; }
122 void mark_transformed_long_inner_loop() { _loop_flags |= TransformedLongInnerLoop; }
123 void mark_transformed_long_outer_loop() { _loop_flags |= TransformedLongOuterLoop; }
124
125 int unswitch_max() { return _unswitch_max; }
126 int unswitch_count() { return _unswitch_count; }
127
128 int has_been_range_checked() const { return _postloop_flags & LoopRCEChecked; }
129 void set_has_been_range_checked() { _postloop_flags |= LoopRCEChecked; }
130 int is_rce_post_loop() const { return _postloop_flags & RCEPostLoop; }
131 void set_is_rce_post_loop() { _postloop_flags |= RCEPostLoop; }
132
133 void set_unswitch_count(int val) {
134 assert (val <= unswitch_max(), "too many unswitches");
135 _unswitch_count = val;
136 }
137
138 void set_profile_trip_cnt(float ptc) { _profile_trip_cnt = ptc; }
139 float profile_trip_cnt() { return _profile_trip_cnt; }
140
141 LoopNode(Node *entry, Node *backedge)
142 : RegionNode(3), _loop_flags(0), _unswitch_count(0),
143 _postloop_flags(0), _profile_trip_cnt(COUNT_UNKNOWN) {
1339 return !has_node(n) || n->is_unreachable(_igvn);
1340 }
1341
1342 // Eliminate range-checks and other trip-counter vs loop-invariant tests.
1343 int do_range_check( IdealLoopTree *loop, Node_List &old_new );
1344
1345 // Check to see if do_range_check(...) cleaned the main loop of range-checks
1346 void has_range_checks(IdealLoopTree *loop);
1347
1348 // Process post loops which have range checks and try to build a multi-version
1349 // guard to safely determine if we can execute the post loop which was RCE'd.
1350 bool multi_version_post_loops(IdealLoopTree *rce_loop, IdealLoopTree *legacy_loop);
1351
1352 // Cause the rce'd post loop to optimized away, this happens if we cannot complete multiverioning
1353 void poison_rce_post_loop(IdealLoopTree *rce_loop);
1354
1355 // Create a slow version of the loop by cloning the loop
1356 // and inserting an if to select fast-slow versions.
1357 // Return the inserted if.
1358 IfNode* create_slow_version_of_loop(IdealLoopTree *loop,
1359 Node_List &old_new,
1360 IfNode* unswitch_iff,
1361 CloneLoopMode mode);
1362
1363 // Clone a loop and return the clone head (clone_loop_head).
1364 // Added nodes include int(1), int(0) - disconnected, If, IfTrue, IfFalse,
1365 // This routine was created for usage in CountedLoopReserveKit.
1366 //
1367 // int(1) -> If -> IfTrue -> original_loop_head
1368 // |
1369 // V
1370 // IfFalse -> clone_loop_head (returned by function pointer)
1371 //
1372 LoopNode* create_reserve_version_of_loop(IdealLoopTree *loop, CountedLoopReserveKit* lk);
1373 // Clone loop with an invariant test (that does not exit) and
1374 // insert a clone of the test that selects which version to
1375 // execute.
1376 void do_unswitching (IdealLoopTree *loop, Node_List &old_new);
1377
1378 // Find candidate "if" for unswitching
1379 IfNode* find_unswitching_candidate(const IdealLoopTree *loop) const;
1380
1381 // Range Check Elimination uses this function!
1382 // Constrain the main loop iterations so the affine function:
1383 // low_limit <= scale_con * I + offset < upper_limit
1384 // always holds true. That is, either increase the number of iterations in
1385 // the pre-loop or the post-loop until the condition holds true in the main
1386 // loop. Scale_con, offset and limit are all loop invariant.
1387 void add_constraint(jlong stride_con, jlong scale_con, Node* offset, Node* low_limit, Node* upper_limit, Node* pre_ctrl, Node** pre_limit, Node** main_limit);
1388 // Helper function for add_constraint().
1389 Node* adjust_limit(bool reduce, Node* scale, Node* offset, Node* rc_limit, Node* old_limit, Node* pre_ctrl, bool round);
1390
1391 // Partially peel loop up through last_peel node.
1392 bool partial_peel( IdealLoopTree *loop, Node_List &old_new );
1393
1394 // Create a scheduled list of nodes control dependent on ctrl set.
1395 void scheduled_nodelist( IdealLoopTree *loop, VectorSet& ctrl, Node_List &sched );
1396 // Has a use in the vector set
1397 bool has_use_in_set( Node* n, VectorSet& vset );
1398 // Has use internal to the vector set (ie. not in a phi at the loop head)
1399 bool has_use_internal_to_set( Node* n, VectorSet& vset, IdealLoopTree *loop );
1480 bool intrinsify_fill(IdealLoopTree* lpt);
1481 bool match_fill_loop(IdealLoopTree* lpt, Node*& store, Node*& store_value,
1482 Node*& shift, Node*& offset);
1483
1484 private:
1485 // Return a type based on condition control flow
1486 const TypeInt* filtered_type( Node *n, Node* n_ctrl);
1487 const TypeInt* filtered_type( Node *n ) { return filtered_type(n, NULL); }
1488 // Helpers for filtered type
1489 const TypeInt* filtered_type_from_dominators( Node* val, Node *val_ctrl);
1490
1491 // Helper functions
1492 Node *spinup( Node *iff, Node *new_false, Node *new_true, Node *region, Node *phi, small_cache *cache );
1493 Node *find_use_block( Node *use, Node *def, Node *old_false, Node *new_false, Node *old_true, Node *new_true );
1494 void handle_use( Node *use, Node *def, small_cache *cache, Node *region_dom, Node *new_false, Node *new_true, Node *old_false, Node *old_true );
1495 bool split_up( Node *n, Node *blk1, Node *blk2 );
1496 void sink_use( Node *use, Node *post_loop );
1497 Node* place_outside_loop(Node* useblock, IdealLoopTree* loop) const;
1498 Node* try_move_store_before_loop(Node* n, Node *n_ctrl);
1499 void try_move_store_after_loop(Node* n);
1500 bool identical_backtoback_ifs(Node *n);
1501 bool can_split_if(Node *n_ctrl);
1502
1503 // Determine if a method is too big for a/another round of split-if, based on
1504 // a magic (approximate) ratio derived from the equally magic constant 35000,
1505 // previously used for this purpose (but without relating to the node limit).
1506 bool must_throttle_split_if() {
1507 uint threshold = C->max_node_limit() * 2 / 5;
1508 return C->live_nodes() > threshold;
1509 }
1510
1511 // A simplistic node request tracking mechanism, where
1512 // = UINT_MAX Request not valid or made final.
1513 // < UINT_MAX Nodes currently requested (estimate).
1514 uint _nodes_required;
1515
1516 enum { REQUIRE_MIN = 70 };
1517
1518 uint nodes_required() const { return _nodes_required; }
1519
1520 // Given the _currently_ available number of nodes, check whether there is
|
61 uint _loop_flags;
62 // Names for flag bitfields
63 enum { Normal=0, Pre=1, Main=2, Post=3, PreMainPostFlagsMask=3,
64 MainHasNoPreLoop = 1<<2,
65 HasExactTripCount = 1<<3,
66 InnerLoop = 1<<4,
67 PartialPeelLoop = 1<<5,
68 PartialPeelFailed = 1<<6,
69 HasReductions = 1<<7,
70 WasSlpAnalyzed = 1<<8,
71 PassedSlpAnalysis = 1<<9,
72 DoUnrollOnly = 1<<10,
73 VectorizedLoop = 1<<11,
74 HasAtomicPostLoop = 1<<12,
75 HasRangeChecks = 1<<13,
76 IsMultiversioned = 1<<14,
77 StripMined = 1<<15,
78 SubwordLoop = 1<<16,
79 ProfileTripFailed = 1<<17,
80 TransformedLongInnerLoop = 1<<18,
81 TransformedLongOuterLoop = 1<<19,
82 FlattenedArrays = 1<<20};
83 char _unswitch_count;
84 enum { _unswitch_max=3 };
85 char _postloop_flags;
86 enum { LoopNotRCEChecked = 0, LoopRCEChecked = 1, RCEPostLoop = 2 };
87
88 // Expected trip count from profile data
89 float _profile_trip_cnt;
90
91 public:
92 // Names for edge indices
93 enum { Self=0, EntryControl, LoopBackControl };
94
95 bool is_inner_loop() const { return _loop_flags & InnerLoop; }
96 void set_inner_loop() { _loop_flags |= InnerLoop; }
97
98 bool range_checks_present() const { return _loop_flags & HasRangeChecks; }
99 bool is_multiversioned() const { return _loop_flags & IsMultiversioned; }
100 bool is_vectorized_loop() const { return _loop_flags & VectorizedLoop; }
101 bool is_partial_peel_loop() const { return _loop_flags & PartialPeelLoop; }
102 void set_partial_peel_loop() { _loop_flags |= PartialPeelLoop; }
103 bool partial_peel_has_failed() const { return _loop_flags & PartialPeelFailed; }
104 bool is_strip_mined() const { return _loop_flags & StripMined; }
105 bool is_profile_trip_failed() const { return _loop_flags & ProfileTripFailed; }
106 bool is_subword_loop() const { return _loop_flags & SubwordLoop; }
107 bool is_transformed_long_inner_loop() const { return _loop_flags & TransformedLongInnerLoop; }
108 bool is_transformed_long_outer_loop() const { return _loop_flags & TransformedLongOuterLoop; }
109 bool is_flattened_arrays() const { return _loop_flags & FlattenedArrays; }
110
111 void mark_partial_peel_failed() { _loop_flags |= PartialPeelFailed; }
112 void mark_has_reductions() { _loop_flags |= HasReductions; }
113 void mark_was_slp() { _loop_flags |= WasSlpAnalyzed; }
114 void mark_passed_slp() { _loop_flags |= PassedSlpAnalysis; }
115 void mark_do_unroll_only() { _loop_flags |= DoUnrollOnly; }
116 void mark_loop_vectorized() { _loop_flags |= VectorizedLoop; }
117 void mark_has_atomic_post_loop() { _loop_flags |= HasAtomicPostLoop; }
118 void mark_has_range_checks() { _loop_flags |= HasRangeChecks; }
119 void mark_is_multiversioned() { _loop_flags |= IsMultiversioned; }
120 void mark_strip_mined() { _loop_flags |= StripMined; }
121 void clear_strip_mined() { _loop_flags &= ~StripMined; }
122 void mark_profile_trip_failed() { _loop_flags |= ProfileTripFailed; }
123 void mark_subword_loop() { _loop_flags |= SubwordLoop; }
124 void mark_transformed_long_inner_loop() { _loop_flags |= TransformedLongInnerLoop; }
125 void mark_transformed_long_outer_loop() { _loop_flags |= TransformedLongOuterLoop; }
126 void mark_flattened_arrays() { _loop_flags |= FlattenedArrays; }
127
128 int unswitch_max() { return _unswitch_max; }
129 int unswitch_count() { return _unswitch_count; }
130
131 int has_been_range_checked() const { return _postloop_flags & LoopRCEChecked; }
132 void set_has_been_range_checked() { _postloop_flags |= LoopRCEChecked; }
133 int is_rce_post_loop() const { return _postloop_flags & RCEPostLoop; }
134 void set_is_rce_post_loop() { _postloop_flags |= RCEPostLoop; }
135
136 void set_unswitch_count(int val) {
137 assert (val <= unswitch_max(), "too many unswitches");
138 _unswitch_count = val;
139 }
140
141 void set_profile_trip_cnt(float ptc) { _profile_trip_cnt = ptc; }
142 float profile_trip_cnt() { return _profile_trip_cnt; }
143
144 LoopNode(Node *entry, Node *backedge)
145 : RegionNode(3), _loop_flags(0), _unswitch_count(0),
146 _postloop_flags(0), _profile_trip_cnt(COUNT_UNKNOWN) {
1342 return !has_node(n) || n->is_unreachable(_igvn);
1343 }
1344
1345 // Eliminate range-checks and other trip-counter vs loop-invariant tests.
1346 int do_range_check( IdealLoopTree *loop, Node_List &old_new );
1347
1348 // Check to see if do_range_check(...) cleaned the main loop of range-checks
1349 void has_range_checks(IdealLoopTree *loop);
1350
1351 // Process post loops which have range checks and try to build a multi-version
1352 // guard to safely determine if we can execute the post loop which was RCE'd.
1353 bool multi_version_post_loops(IdealLoopTree *rce_loop, IdealLoopTree *legacy_loop);
1354
1355 // Cause the rce'd post loop to optimized away, this happens if we cannot complete multiverioning
1356 void poison_rce_post_loop(IdealLoopTree *rce_loop);
1357
1358 // Create a slow version of the loop by cloning the loop
1359 // and inserting an if to select fast-slow versions.
1360 // Return the inserted if.
1361 IfNode* create_slow_version_of_loop(IdealLoopTree *loop,
1362 Node_List &old_new,
1363 Node_List &unswitch_iffs,
1364 CloneLoopMode mode);
1365
1366 // Clone a loop and return the clone head (clone_loop_head).
1367 // Added nodes include int(1), int(0) - disconnected, If, IfTrue, IfFalse,
1368 // This routine was created for usage in CountedLoopReserveKit.
1369 //
1370 // int(1) -> If -> IfTrue -> original_loop_head
1371 // |
1372 // V
1373 // IfFalse -> clone_loop_head (returned by function pointer)
1374 //
1375 LoopNode* create_reserve_version_of_loop(IdealLoopTree *loop, CountedLoopReserveKit* lk);
1376 // Clone loop with an invariant test (that does not exit) and
1377 // insert a clone of the test that selects which version to
1378 // execute.
1379 void do_unswitching (IdealLoopTree *loop, Node_List &old_new);
1380
1381 // Find candidate "if" for unswitching
1382 IfNode* find_unswitching_candidate(const IdealLoopTree *loop, Node_List& unswitch_iffs) const;
1383
1384 // Range Check Elimination uses this function!
1385 // Constrain the main loop iterations so the affine function:
1386 // low_limit <= scale_con * I + offset < upper_limit
1387 // always holds true. That is, either increase the number of iterations in
1388 // the pre-loop or the post-loop until the condition holds true in the main
1389 // loop. Scale_con, offset and limit are all loop invariant.
1390 void add_constraint(jlong stride_con, jlong scale_con, Node* offset, Node* low_limit, Node* upper_limit, Node* pre_ctrl, Node** pre_limit, Node** main_limit);
1391 // Helper function for add_constraint().
1392 Node* adjust_limit(bool reduce, Node* scale, Node* offset, Node* rc_limit, Node* old_limit, Node* pre_ctrl, bool round);
1393
1394 // Partially peel loop up through last_peel node.
1395 bool partial_peel( IdealLoopTree *loop, Node_List &old_new );
1396
1397 // Create a scheduled list of nodes control dependent on ctrl set.
1398 void scheduled_nodelist( IdealLoopTree *loop, VectorSet& ctrl, Node_List &sched );
1399 // Has a use in the vector set
1400 bool has_use_in_set( Node* n, VectorSet& vset );
1401 // Has use internal to the vector set (ie. not in a phi at the loop head)
1402 bool has_use_internal_to_set( Node* n, VectorSet& vset, IdealLoopTree *loop );
1483 bool intrinsify_fill(IdealLoopTree* lpt);
1484 bool match_fill_loop(IdealLoopTree* lpt, Node*& store, Node*& store_value,
1485 Node*& shift, Node*& offset);
1486
1487 private:
1488 // Return a type based on condition control flow
1489 const TypeInt* filtered_type( Node *n, Node* n_ctrl);
1490 const TypeInt* filtered_type( Node *n ) { return filtered_type(n, NULL); }
1491 // Helpers for filtered type
1492 const TypeInt* filtered_type_from_dominators( Node* val, Node *val_ctrl);
1493
1494 // Helper functions
1495 Node *spinup( Node *iff, Node *new_false, Node *new_true, Node *region, Node *phi, small_cache *cache );
1496 Node *find_use_block( Node *use, Node *def, Node *old_false, Node *new_false, Node *old_true, Node *new_true );
1497 void handle_use( Node *use, Node *def, small_cache *cache, Node *region_dom, Node *new_false, Node *new_true, Node *old_false, Node *old_true );
1498 bool split_up( Node *n, Node *blk1, Node *blk2 );
1499 void sink_use( Node *use, Node *post_loop );
1500 Node* place_outside_loop(Node* useblock, IdealLoopTree* loop) const;
1501 Node* try_move_store_before_loop(Node* n, Node *n_ctrl);
1502 void try_move_store_after_loop(Node* n);
1503 void move_flat_array_check_out_of_loop(Node* n);
1504 bool identical_backtoback_ifs(Node *n);
1505 bool flatten_array_element_type_check(Node *n);
1506 bool can_split_if(Node *n_ctrl);
1507
1508 // Determine if a method is too big for a/another round of split-if, based on
1509 // a magic (approximate) ratio derived from the equally magic constant 35000,
1510 // previously used for this purpose (but without relating to the node limit).
1511 bool must_throttle_split_if() {
1512 uint threshold = C->max_node_limit() * 2 / 5;
1513 return C->live_nodes() > threshold;
1514 }
1515
1516 // A simplistic node request tracking mechanism, where
1517 // = UINT_MAX Request not valid or made final.
1518 // < UINT_MAX Nodes currently requested (estimate).
1519 uint _nodes_required;
1520
1521 enum { REQUIRE_MIN = 70 };
1522
1523 uint nodes_required() const { return _nodes_required; }
1524
1525 // Given the _currently_ available number of nodes, check whether there is
|