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Quellcode-Bibliothek© Kompilation durch diese Firma[Weder Korrektheit noch Funktionsfähigkeit der Software werden zugesichert.]Datei: ku.xml Sprache: C |
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/*
* Copyright (c) 1998, 2022, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #ifndef SHARE_OPTO_LOOPNODE_HPP #define SHARE_OPTO_LOOPNODE_HPP #include "opto/cfgnode.hpp" #include "opto/multnode.hpp" #include "opto/phaseX.hpp" #include "opto/subnode.hpp" #include "opto/type.hpp" class CmpNode; class BaseCountedLoopEndNode; class CountedLoopNode; class IdealLoopTree; class LoopNode; class Node; class OuterStripMinedLoopEndNode; class PathFrequency; class PhaseIdealLoop; class CountedLoopReserveKit; class VectorSet; class Invariance; struct small_cache; // // I D E A L I Z E D L O O P S // // Idealized loops are the set of loops I perform more interesting // transformations on, beyond simple hoisting. //------------------------------LoopNode--------------------------------------- // Simple loop header. Fall in path on left, loop-back path on right. class LoopNode : public RegionNode { // Size is bigger to hold the flags. However, the flags do not change // the semantics so it does not appear in the hash & cmp functions. virtual uint size_of() const { return sizeof(*this); } protected: uint _loop_flags; // Names for flag bitfields enum { Normal=0, Pre=1, Main=2, Post=3, PreMainPostFlagsMask=3, MainHasNoPreLoop = 1<<2, HasExactTripCount = 1<<3, InnerLoop = 1<<4, PartialPeelLoop = 1<<5, PartialPeelFailed = 1<<6, HasReductions = 1<<7, WasSlpAnalyzed = 1<<8, PassedSlpAnalysis = 1<<9, DoUnrollOnly = 1<<10, VectorizedLoop = 1<<11, HasAtomicPostLoop = 1<<12, HasRangeChecks = 1<<13, IsMultiversioned = 1<<14, StripMined = 1<<15, SubwordLoop = 1<<16, ProfileTripFailed = 1<<17, LoopNestInnerLoop = 1 << 18, LoopNestLongOuterLoop = 1 << 19}; char _unswitch_count; enum { _unswitch_max=3 }; char _postloop_flags; enum { LoopNotRCEChecked = 0, LoopRCEChecked = 1, RCEPostLoop = 2 }; // Expected trip count from profile data float _profile_trip_cnt; public: // Names for edge indices enum { Self=0, EntryControl, LoopBackControl }; bool is_inner_loop() const { return _loop_flags & InnerLoop; } void set_inner_loop() { _loop_flags |= InnerLoop; } bool range_checks_present() const { return _loop_flags & HasRangeChecks; } bool is_multiversioned() const { return _loop_flags & IsMultiversioned; } bool is_vectorized_loop() const { return _loop_flags & VectorizedLoop; } bool is_partial_peel_loop() const { return _loop_flags & PartialPeelLoop; } void set_partial_peel_loop() { _loop_flags |= PartialPeelLoop; } bool partial_peel_has_failed() const { return _loop_flags & PartialPeelFailed; } bool is_strip_mined() const { return _loop_flags & StripMined; } bool is_profile_trip_failed() const { return _loop_flags & ProfileTripFailed; } bool is_subword_loop() const { return _loop_flags & SubwordLoop; } bool is_loop_nest_inner_loop() const { return _loop_flags & LoopNestInnerLoop; } bool is_loop_nest_outer_loop() const { return _loop_flags & LoopNestLongOuterLoop; } void mark_partial_peel_failed() { _loop_flags |= PartialPeelFailed; } void mark_has_reductions() { _loop_flags |= HasReductions; } void mark_was_slp() { _loop_flags |= WasSlpAnalyzed; } void mark_passed_slp() { _loop_flags |= PassedSlpAnalysis; } void mark_do_unroll_only() { _loop_flags |= DoUnrollOnly; } void mark_loop_vectorized() { _loop_flags |= VectorizedLoop; } void mark_has_atomic_post_loop() { _loop_flags |= HasAtomicPostLoop; } void mark_has_range_checks() { _loop_flags |= HasRangeChecks; } void clear_has_range_checks() { _loop_flags &= ~HasRangeChecks; } void mark_is_multiversioned() { _loop_flags |= IsMultiversioned; } void mark_strip_mined() { _loop_flags |= StripMined; } void clear_strip_mined() { _loop_flags &= ~StripMined; } void mark_profile_trip_failed() { _loop_flags |= ProfileTripFailed; } void mark_subword_loop() { _loop_flags |= SubwordLoop; } void mark_loop_nest_inner_loop() { _loop_flags |= LoopNestInnerLoop; } void mark_loop_nest_outer_loop() { _loop_flags |= LoopNestLongOuterLoop; } int unswitch_max() { return _unswitch_max; } int unswitch_count() { return _unswitch_count; } int has_been_range_checked() const { return _postloop_flags & LoopRCEChecked; } void set_has_been_range_checked() { _postloop_flags |= LoopRCEChecked; } int is_rce_post_loop() const { return _postloop_flags & RCEPostLoop; } void set_is_rce_post_loop() { _postloop_flags |= RCEPostLoop; } void set_unswitch_count(int val) { assert (val <= unswitch_max(), "too many unswitches"); _unswitch_count = val; } void set_profile_trip_cnt(float ptc) { _profile_trip_cnt = ptc; } float profile_trip_cnt() { return _profile_trip_cnt; } LoopNode(Node *entry, Node *backedge) : RegionNode(3), _loop_flags(0), _unswitch_count(0), _postloop_flags(0), _profile_trip_cnt(COUNT_UNKNOWN) { init_class_id(Class_Loop); init_req(EntryControl, entry); init_req(LoopBackControl, backedge); } virtual Node *Ideal(PhaseGVN *phase, bool can_reshape); virtual int Opcode() const; bool can_be_counted_loop(PhaseTransform* phase) const { return req() == 3 && in(0) != NULL && in(1) != NULL && phase->type(in(1)) != Type::TOP && in(2) != NULL && phase->type(in(2)) != Type::TOP; } bool is_valid_counted_loop(BasicType bt) const; #ifndef PRODUCT virtual void dump_spec(outputStream *st) const; #endif void verify_strip_mined(int expect_skeleton) const NOT_DEBUG_RETURN; virtual LoopNode* skip_strip_mined(int expect_skeleton = 1) { return this; } virtual IfTrueNode* outer_loop_tail() const { ShouldNotReachHere(); return NULL; } virtual OuterStripMinedLoopEndNode* outer_loop_end() const { ShouldNotReachHere(); ret virtual IfFalseNode* outer_loop_exit() const { ShouldNotReachHere(); return NULL; } virtual SafePointNode* outer_safepoint() const { ShouldNotReachHere(); return NULL; } }; //------------------------------Counted Loops---------------------------------- // Counted loops are all trip-counted loops, with exactly 1 trip-counter exit // path (and maybe some other exit paths). The trip-counter exit is always // last in the loop. The trip-counter have to stride by a constant; // the exit value is also loop invariant. // CountedLoopNodes and CountedLoopEndNodes come in matched pairs. The // CountedLoopNode has the incoming loop control and the loop-back-control // which is always the IfTrue before the matching CountedLoopEndNode. The // CountedLoopEndNode has an incoming control (possibly not the // CountedLoopNode if there is control flow in the loop), the post-increment // trip-counter value, and the limit. The trip-counter value is always of // the form (Op old-trip-counter stride). The old-trip-counter is produced // by a Phi connected to the CountedLoopNode. The stride is constant. // The Op is any commutable opcode, including Add, Mul, Xor. The // CountedLoopEndNode also takes in the loop-invariant limit value. // From a CountedLoopNode I can reach the matching CountedLoopEndNode via the // loop-back control. From CountedLoopEndNodes I can reach CountedLoopNodes // via the old-trip-counter from the Op node. //------------------------------CountedLoopNode-------------------------------- // CountedLoopNodes head simple counted loops. CountedLoopNodes have as // inputs the incoming loop-start control and the loop-back control, so they // act like RegionNodes. They also take in the initial trip counter, the // loop-invariant stride and the loop-invariant limit value. CountedLoopNodes // produce a loop-body control and the trip counter value. Since // CountedLoopNodes behave like RegionNodes I still have a standard CFG model. class BaseCountedLoopNode : public LoopNode { public: BaseCountedLoopNode(Node *entry, Node *backedge) : LoopNode(entry, backedge) { } Node *init_control() const { return in(EntryControl); } Node *back_control() const { return in(LoopBackControl); } Node* init_trip() const; Node* stride() const; bool stride_is_con() const; Node* limit() const; Node* incr() const; Node* phi() const; BaseCountedLoopEndNode* loopexit_or_null() const; BaseCountedLoopEndNode* loopexit() const; virtual BasicType bt() const = 0; jlong stride_con() const; static BaseCountedLoopNode* make(Node* entry, Node* backedge, BasicType bt); }; class CountedLoopNode : public BaseCountedLoopNode { // Size is bigger to hold _main_idx. However, _main_idx does not change // the semantics so it does not appear in the hash & cmp functions. virtual uint size_of() const { return sizeof(*this); } // For Pre- and Post-loops during debugging ONLY, this holds the index of // the Main CountedLoop. Used to assert that we understand the graph shape. node_idx_t _main_idx; // Known trip count calculated by compute_exact_trip_count() uint _trip_count; // Log2 of original loop bodies in unrolled loop int _unrolled_count_log2; // Node count prior to last unrolling - used to decide if // unroll,optimize,unroll,optimize,... is making progress int _node_count_before_unroll; // If slp analysis is performed we record the maximum // vector mapped unroll factor here int _slp_maximum_unroll_factor; // The eventual count of vectorizable packs in slp int _slp_vector_pack_count; public: CountedLoopNode(Node *entry, Node *backedge) : BaseCountedLoopNode(entry, backedge), _main_idx(0), _trip_count(max_juint), _unrolled_count_log2(0), _node_count_before_unroll(0), _slp_maximum_unroll_factor(0), _slp_vector_pack_count(0) { init_class_id(Class_CountedLoop); // Initialize _trip_count to the largest possible value. // Will be reset (lower) if the loop's trip count is known. } virtual int Opcode() const; virtual Node *Ideal(PhaseGVN *phase, bool can_reshape); CountedLoopEndNode* loopexit_or_null() const { return (CountedLoopEndNode*) BaseCounte CountedLoopEndNode* loopexit() const { return (CountedLoopEndNode*) BaseCountedLoopNod int stride_con() const; // Match increment with optional truncation static Node* match_incr_with_optional_truncation(Node* expr, Node** trunc1, Node** trunc2, const Typ BasicType bt); // A 'main' loop has a pre-loop and a post-loop. The 'main' loop // can run short a few iterations and may start a few iterations in. // It will be RCE'd and unrolled and aligned. // A following 'post' loop will run any remaining iterations. Used // during Range Check Elimination, the 'post' loop will do any final // iterations with full checks. Also used by Loop Unrolling, where // the 'post' loop will do any epilog iterations needed. Basically, // a 'post' loop can not profitably be further unrolled or RCE'd. // A preceding 'pre' loop will run at least 1 iteration (to do peeling), // it may do under-flow checks for RCE and may do alignment iterations // so the following main loop 'knows' that it is striding down cache // lines. // A 'main' loop that is ONLY unrolled or peeled, never RCE'd or // Aligned, may be missing it's pre-loop. bool is_normal_loop () const { return (_loop_flags&PreMainPostFlagsMask) == Normal; } bool is_pre_loop () const { return (_loop_flags&PreMainPostFlagsMask) == Pre; } bool is_main_loop () const { return (_loop_flags&PreMainPostFlagsMask) == Main; } bool is_post_loop () const { return (_loop_flags&PreMainPostFlagsMask) == Post; } bool is_reduction_loop() const { return (_loop_flags&HasReductions) == HasReductions; } bool was_slp_analyzed () const { return (_loop_flags&WasSlpAnalyzed) == WasSlpAnalyzed; } bool has_passed_slp () const { return (_loop_flags&PassedSlpAnalysis) == PassedSlpAnalysis; } bool is_unroll_only () const { return (_loop_flags&DoUnrollOnly) == DoUnrollOnly; } bool is_main_no_pre_loop() const { return _loop_flags & MainHasNoPreLoop; } bool has_atomic_post_loop () const { return (_loop_flags & HasAtomicPostLoop) == HasAt void set_main_no_pre_loop() { _loop_flags |= MainHasNoPreLoop; } int main_idx() const { return _main_idx; } void set_pre_loop (CountedLoopNode *main) { assert(is_normal_loop(),""); _loop_flags |= void set_main_loop ( ) { assert(is_normal_loop(),""); _loop_flags |= Main; } void set_post_loop (CountedLoopNode *main) { assert(is_normal_loop(),""); _loop_flags | void set_normal_loop( ) { _loop_flags &= ~PreMainPostFlagsMask; } void set_trip_count(uint tc) { _trip_count = tc; } uint trip_count() { return _trip_count; } bool has_exact_trip_count() const { return (_loop_flags & HasExactTripCount) != 0; } void set_exact_trip_count(uint tc) { _trip_count = tc; _loop_flags |= HasExactTripCount; } void set_nonexact_trip_count() { _loop_flags &= ~HasExactTripCount; } void set_notpassed_slp() { _loop_flags &= ~PassedSlpAnalysis; } void double_unrolled_count() { _unrolled_count_log2++; } int unrolled_count() { return 1 << MIN2(_unrolled_count_log2, BitsPerInt-3); } void set_node_count_before_unroll(int ct) { _node_count_before_unroll = ct; } int node_count_before_unroll() { return _node_count_before_unroll; } void set_slp_max_unroll(int unroll_factor) { _slp_maximum_unroll_factor = unroll_facto int slp_max_unroll() const { return _slp_maximum_unroll_factor; } void set_slp_pack_count(int pack_count) { _slp_vector_pack_count = pack_count; } int slp_pack_count() const { return _slp_vector_pack_count; } virtual LoopNode* skip_strip_mined(int expect_skeleton = 1); OuterStripMinedLoopNode* outer_loop() const; virtual IfTrueNode* outer_loop_tail() const; virtual OuterStripMinedLoopEndNode* outer_loop_end() const; virtual IfFalseNode* outer_loop_exit() const; virtual SafePointNode* outer_safepoint() const; // If this is a main loop in a pre/main/post loop nest, walk over // the predicates that were inserted by // duplicate_predicates()/add_range_check_predicate() static Node* skip_predicates_from_entry(Node* ctrl); Node* skip_predicates(); virtual BasicType bt() const { return T_INT; } Node* is_canonical_loop_entry(); #ifndef PRODUCT virtual void dump_spec(outputStream *st) const; #endif static bool is_zero_trip_guard_if(const IfNode* iff); }; class LongCountedLoopNode : public BaseCountedLoopNode { public: LongCountedLoopNode(Node *entry, Node *backedge) : BaseCountedLoopNode(entry, backedge) { init_class_id(Class_LongCountedLoop); } virtual int Opcode() const; virtual BasicType bt() const { return T_LONG; } LongCountedLoopEndNode* loopexit_or_null() const { return (LongCountedLoopEndNode*) Ba LongCountedLoopEndNode* loopexit() const { return (LongCountedLoopEndNode*) BaseCounte }; //------------------------------CountedLoopEndNode----------------------------- // CountedLoopEndNodes end simple trip counted loops. They act much like // IfNodes. class BaseCountedLoopEndNode : public IfNode { public: enum { TestControl, TestValue }; BaseCountedLoopEndNode(Node *control, Node *test, float prob, float cnt) : IfNode(control, test, prob, cnt) { init_class_id(Class_BaseCountedLoopEnd); } Node *cmp_node() const { return (in(TestValue)->req() >=2) ? in(TestValue)->in(1) : NULL; } Node* incr() const { Node* tmp = cmp_node(); return (tmp && tmp->req() == 3) ? tmp->in(1) : NULL; } Node* limit() const { Node* tmp = cmp_node(); return (tmp && tmp->req() == 3) ? tmp->in(2) : NULL; } Node* stride() const { Node* tmp = incr(); return (tmp && tmp->req() == 3) ? tmp->in(2) : NULL; } Node* init_trip() const { Node* tmp = phi(); return (tmp && tmp->req() == 3) ? tmp->in(1) : NULL; } bool stride_is_con() const { Node *tmp = stride(); return (tmp != NULL && tmp->is_Con()); } PhiNode* phi() const { Node* tmp = incr(); if (tmp && tmp->req() == 3) { Node* phi = tmp->in(1); if (phi->is_Phi()) { return phi->as_Phi(); } } return NULL; } BaseCountedLoopNode* loopnode() const { // The CountedLoopNode that goes with this CountedLoopEndNode may // have been optimized out by the IGVN so be cautious with the // pattern matching on the graph PhiNode* iv_phi = phi(); if (iv_phi == NULL) { return NULL; } Node* ln = iv_phi->in(0); if (!ln->is_BaseCountedLoop() || ln->as_BaseCountedLoop()->loopexit_or_null() != this) { return NULL; } if (ln->as_BaseCountedLoop()->bt() != bt()) { return NULL; } return ln->as_BaseCountedLoop(); } BoolTest::mask test_trip() const { return in(TestValue)->as_Bool()->_test._test; } jlong stride_con() const; virtual BasicType bt() const = 0; static BaseCountedLoopEndNode* make(Node* control, Node* test, float prob, float cnt, Basi }; class CountedLoopEndNode : public BaseCountedLoopEndNode { public: CountedLoopEndNode(Node *control, Node *test, float prob, float cnt) : BaseCountedLoopEndNode(control, test, prob, cnt) { init_class_id(Class_CountedLoopEnd); } virtual int Opcode() const; CountedLoopNode* loopnode() const { return (CountedLoopNode*) BaseCountedLoopEndNode::loopnode(); } virtual BasicType bt() const { return T_INT; } #ifndef PRODUCT virtual void dump_spec(outputStream *st) const; #endif }; class LongCountedLoopEndNode : public BaseCountedLoopEndNode { public: LongCountedLoopEndNode(Node *control, Node *test, float prob, float cnt) : BaseCountedLoopEndNode(control, test, prob, cnt) { init_class_id(Class_LongCountedLoopEnd); } LongCountedLoopNode* loopnode() const { return (LongCountedLoopNode*) BaseCountedLoopEndNode::loopnode(); } virtual int Opcode() const; virtual BasicType bt() const { return T_LONG; } }; inline BaseCountedLoopEndNode* BaseCountedLoopNode::loopexit_or_null() const { Node* bctrl = back_control(); if (bctrl == NULL) return NULL; Node* lexit = bctrl->in(0); if (!lexit->is_BaseCountedLoopEnd()) { return NULL; } BaseCountedLoopEndNode* result = lexit->as_BaseCountedLoopEnd(); if (result->bt() != bt()) { return NULL; } return result; } inline BaseCountedLoopEndNode* BaseCountedLoopNode::loopexit() const { BaseCountedLoopEndNode* cle = loopexit_or_null(); assert(cle != NULL, "loopexit is NULL"); return cle; } inline Node* BaseCountedLoopNode::init_trip() const { BaseCountedLoopEndNode* cle = loopexit_or_null(); return cle != NULL ? cle->init_trip() : NULL; } inline Node* BaseCountedLoopNode::stride() const { BaseCountedLoopEndNode* cle = loopexit_or_null(); return cle != NULL ? cle->stride() : NULL; } inline bool BaseCountedLoopNode::stride_is_con() const { BaseCountedLoopEndNode* cle = loopexit_or_null(); return cle != NULL && cle->stride_is_con(); } inline Node* BaseCountedLoopNode::limit() const { BaseCountedLoopEndNode* cle = loopexit_or_null(); return cle != NULL ? cle->limit() : NULL; } inline Node* BaseCountedLoopNode::incr() const { BaseCountedLoopEndNode* cle = loopexit_or_null(); return cle != NULL ? cle->incr() : NULL; } inline Node* BaseCountedLoopNode::phi() const { BaseCountedLoopEndNode* cle = loopexit_or_null(); return cle != NULL ? cle->phi() : NULL; } inline jlong BaseCountedLoopNode::stride_con() const { BaseCountedLoopEndNode* cle = loopexit_or_null(); return cle != NULL ? cle->stride_con() : 0; } //------------------------------LoopLimitNode----------------------------- // Counted Loop limit node which represents exact final iterator value: // trip_count = (limit - init_trip + stride - 1)/stride // final_value= trip_count * stride + init_trip. // Use HW instructions to calculate it when it can overflow in integer. // Note, final_value should fit into integer since counted loop has // limit check: limit <= max_int-stride. class LoopLimitNode : public Node { enum { Init=1, Limit=2, Stride=3 }; public: LoopLimitNode( Compile* C, Node *init, Node *limit, Node *stride ) : Node(0,init,limit,stri // Put it on the Macro nodes list to optimize during macro nodes expansion. init_flags(Flag_is_macro); C->add_macro_node(this); } virtual int Opcode() const; virtual const Type *bottom_type() const { return TypeInt::INT; } virtual uint ideal_reg() const { return Op_RegI; } virtual const Type* Value(PhaseGVN* phase) const; virtual Node *Ideal(PhaseGVN *phase, bool can_reshape); virtual Node* Identity(PhaseGVN* phase); }; // Support for strip mining class OuterStripMinedLoopNode : public LoopNode { private: static void fix_sunk_stores(CountedLoopEndNode* inner_cle, LoopNode* inner_cl, PhaseIt public: OuterStripMinedLoopNode(Compile* C, Node *entry, Node *backedge) : LoopNode(entry, backedge) { init_class_id(Class_OuterStripMinedLoop); init_flags(Flag_is_macro); C->add_macro_node(this); } virtual int Opcode() const; virtual IfTrueNode* outer_loop_tail() const; virtual OuterStripMinedLoopEndNode* outer_loop_end() const; virtual IfFalseNode* outer_loop_exit() const; virtual SafePointNode* outer_safepoint() const; void adjust_strip_mined_loop(PhaseIterGVN* igvn); void remove_outer_loop_and_safepoint(PhaseIterGVN* igvn) const; void transform_to_counted_loop(PhaseIterGVN* igvn, PhaseIdealLoop* iloop); static Node* register_new_node(Node* node, LoopNode* ctrl, PhaseIterGVN* igvn, PhaseIdea Node* register_control(Node* node, Node* loop, Node* idom, PhaseIterGVN* igvn, PhaseIdealLoop* iloop); }; class OuterStripMinedLoopEndNode : public IfNode { public: OuterStripMinedLoopEndNode(Node *control, Node *test, float prob, float cnt) : IfNode(control, test, prob, cnt) { init_class_id(Class_OuterStripMinedLoopEnd); } virtual int Opcode() const; virtual const Type* Value(PhaseGVN* phase) const; virtual Node *Ideal(PhaseGVN *phase, bool can_reshape); bool is_expanded(PhaseGVN *phase) const; }; // -----------------------------IdealLoopTree---------------------------------- class IdealLoopTree : public ResourceObj { public: IdealLoopTree *_parent; // Parent in loop tree IdealLoopTree *_next; // Next sibling in loop tree IdealLoopTree *_child; // First child in loop tree // The head-tail backedge defines the loop. // If a loop has multiple backedges, this is addressed during cleanup where // we peel off the multiple backedges, merging all edges at the bottom and // ensuring that one proper backedge flow into the loop. Node *_head; // Head of loop Node *_tail; // Tail of loop inline Node *tail(); // Handle lazy update of _tail field inline Node *head(); // Handle lazy update of _head field PhaseIdealLoop* _phase; int _local_loop_unroll_limit; int _local_loop_unroll_factor; Node_List _body; // Loop body for inner loops uint16_t _nest; // Nesting depth uint8_t _irreducible:1, // True if irreducible _has_call:1, // True if has call safepoint _has_sfpt:1, // True if has non-call safepoint _rce_candidate:1; // True if candidate for range check elimination Node_List* _safepts; // List of safepoints in this loop Node_List* _required_safept; // A inner loop cannot delete these safepts; bool _allow_optimizations; // Allow loop optimizations IdealLoopTree( PhaseIdealLoop* phase, Node *head, Node *tail ) : _parent(0), _next(0), _child(0), _head(head), _tail(tail), _phase(phase), _local_loop_unroll_limit(0), _local_loop_unroll_factor(0), _nest(0), _irreducible(0), _has_call(0), _has_sfpt(0), _rce_candidate(0), _safepts(NULL), _required_safept(NULL), _allow_optimizations(true) { precond(_head != NULL); precond(_tail != NULL); } // Is 'l' a member of 'this'? bool is_member(const IdealLoopTree *l) const; // Test for nested membership // Set loop nesting depth. Accumulate has_call bits. int set_nest( uint depth ); // Split out multiple fall-in edges from the loop header. Move them to a // private RegionNode before the loop. This becomes the loop landing pad. void split_fall_in( PhaseIdealLoop *phase, int fall_in_cnt ); // Split out the outermost loop from this shared header. void split_outer_loop( PhaseIdealLoop *phase ); // Merge all the backedges from the shared header into a private Region. // Feed that region as the one backedge to this loop. void merge_many_backedges( PhaseIdealLoop *phase ); // Split shared headers and insert loop landing pads. // Insert a LoopNode to replace the RegionNode. // Returns TRUE if loop tree is structurally changed. bool beautify_loops( PhaseIdealLoop *phase ); // Perform optimization to use the loop predicates for null checks and range checks. // Applies to any loop level (not just the innermost one) bool loop_predication( PhaseIdealLoop *phase); // Perform iteration-splitting on inner loops. Split iterations to // avoid range checks or one-shot null checks. Returns false if the // current round of loop opts should stop. bool iteration_split( PhaseIdealLoop *phase, Node_List &old_new ); // Driver for various flavors of iteration splitting. Returns false // if the current round of loop opts should stop. bool iteration_split_impl( PhaseIdealLoop *phase, Node_List &old_new ); // Given dominators, try to find loops with calls that must always be // executed (call dominates loop tail). These loops do not need non-call // safepoints (ncsfpt). void check_safepts(VectorSet &visited, Node_List &stack); // Allpaths backwards scan from loop tail, terminating each path at first safepoint // encountered. void allpaths_check_safepts(VectorSet &visited, Node_List &stack); // Remove safepoints from loop. Optionally keeping one. void remove_safepoints(PhaseIdealLoop* phase, bool keep_one); // Convert to counted loops where possible void counted_loop( PhaseIdealLoop *phase ); // Check for Node being a loop-breaking test Node *is_loop_exit(Node *iff) const; // Remove simplistic dead code from loop body void DCE_loop_body(); // Look for loop-exit tests with my 50/50 guesses from the Parsing stage. // Replace with a 1-in-10 exit guess. void adjust_loop_exit_prob( PhaseIdealLoop *phase ); // Return TRUE or FALSE if the loop should never be RCE'd or aligned. // Useful for unrolling loops with NO array accesses. bool policy_peel_only( PhaseIdealLoop *phase ) const; // Return TRUE or FALSE if the loop should be unswitched -- clone // loop with an invariant test bool policy_unswitching( PhaseIdealLoop *phase ) const; // Micro-benchmark spamming. Remove empty loops. bool do_remove_empty_loop( PhaseIdealLoop *phase ); // Convert one iteration loop into normal code. bool do_one_iteration_loop( PhaseIdealLoop *phase ); // Return TRUE or FALSE if the loop should be peeled or not. Peel if we can // move some loop-invariant test (usually a null-check) before the loop. bool policy_peeling(PhaseIdealLoop *phase); uint estimate_peeling(PhaseIdealLoop *phase); // Return TRUE or FALSE if the loop should be maximally unrolled. Stash any // known trip count in the counted loop node. bool policy_maximally_unroll(PhaseIdealLoop *phase) const; // Return TRUE or FALSE if the loop should be unrolled or not. Apply unroll // if the loop is a counted loop and the loop body is small enough. bool policy_unroll(PhaseIdealLoop *phase); // Loop analyses to map to a maximal superword unrolling for vectorization. void policy_unroll_slp_analysis(CountedLoopNode *cl, PhaseIdealLoop *phase, int future // Return TRUE or FALSE if the loop should be range-check-eliminated. // Gather a list of IF tests that are dominated by iteration splitting; // also gather the end of the first split and the start of the 2nd split. bool policy_range_check(PhaseIdealLoop* phase, bool provisional, BasicType bt) const; // Return TRUE if "iff" is a range check. bool is_range_check_if(IfNode *iff, PhaseIdealLoop *phase, Invariance& invar DEBUG_ bool is_range_check_if(IfNode* iff, PhaseIdealLoop* phase, BasicType bt, Node* iv, Node*&&n jlong& scale) const; // Estimate the number of nodes required when cloning a loop (body). uint est_loop_clone_sz(uint factor) const; // Estimate the number of nodes required when unrolling a loop (body). uint est_loop_unroll_sz(uint factor) const; // Compute loop trip count if possible void compute_trip_count(PhaseIdealLoop* phase); // Compute loop trip count from profile data float compute_profile_trip_cnt_helper(Node* n); void compute_profile_trip_cnt( PhaseIdealLoop *phase ); // Reassociate invariant expressions. void reassociate_invariants(PhaseIdealLoop *phase); // Reassociate invariant binary expressions. Node* reassociate(Node* n1, PhaseIdealLoop *phase); // Reassociate invariant add and subtract expressions. Node* reassociate_add_sub(Node* n1, int inv1_idx, int inv2_idx, PhaseIdealLoop *phase); // Return nonzero index of invariant operand if invariant and variant // are combined with an associative binary. Helper for reassociate_invariants. int find_invariant(Node* n, PhaseIdealLoop *phase); // Return TRUE if "n" is associative. bool is_associative(Node* n, Node* base=NULL); // Return true if n is invariant bool is_invariant(Node* n) const; // Put loop body on igvn work list void record_for_igvn(); bool is_root() { return _parent == NULL; } // A proper/reducible loop w/o any (occasional) dead back-edge. bool is_loop() { return !_irreducible && !tail()->is_top(); } bool is_counted() { return is_loop() && _head->is_CountedLoop(); } bool is_innermost() { return is_loop() && _child == NULL; } void remove_main_post_loops(CountedLoopNode *cl, PhaseIdealLoop *phase); #ifndef PRODUCT void dump_head() const; // Dump loop head only void dump() const; // Dump this loop recursively void verify_tree(IdealLoopTree *loop, const IdealLoopTree *parent) const; #endif private: enum { EMPTY_LOOP_SIZE = 7 }; // Number of nodes in an empty loop. // Estimate the number of nodes resulting from control and data flow merge. uint est_loop_flow_merge_sz() const; // Check if the number of residual iterations is large with unroll_cnt. // Return true if the residual iterations are more than 10% of the trip count. bool is_residual_iters_large(int unroll_cnt, CountedLoopNode *cl) const { return (unroll_cnt - 1) * (100.0 / LoopPercentProfileLimit) > cl->profile_trip_cnt(); } }; // -----------------------------PhaseIdealLoop--------------------------------- // Computes the mapping from Nodes to IdealLoopTrees. Organizes IdealLoopTrees // into a loop tree. Drives the loop-based transformations on the ideal graph. class PhaseIdealLoop : public PhaseTransform { friend class IdealLoopTree; friend class SuperWord; friend class CountedLoopReserveKit; friend class ShenandoahBarrierC2Support; friend class AutoNodeBudget; // Pre-computed def-use info PhaseIterGVN &_igvn; // Head of loop tree IdealLoopTree* _ltree_root; // Array of pre-order numbers, plus post-visited bit. // ZERO for not pre-visited. EVEN for pre-visited but not post-visited. // ODD for post-visited. Other bits are the pre-order number. uint *_preorders; uint _max_preorder; const PhaseIdealLoop* _verify_me; bool _verify_only; // Allocate _preorders[] array void allocate_preorders() { _max_preorder = C->unique()+8; _preorders = NEW_RESOURCE_ARRAY(uint, _max_preorder); memset(_preorders, 0, sizeof(uint) * _max_preorder); } // Allocate _preorders[] array void reallocate_preorders() { if ( _max_preorder < C->unique() ) { _preorders = REALLOC_RESOURCE_ARRAY(uint, _preorders, _max_preorder, C->unique()); _max_preorder = C->unique(); } memset(_preorders, 0, sizeof(uint) * _max_preorder); } // Check to grow _preorders[] array for the case when build_loop_tree_impl() // adds new nodes. void check_grow_preorders( ) { if ( _max_preorder < C->unique() ) { uint newsize = _max_preorder<<1; // double size of array _preorders = REALLOC_RESOURCE_ARRAY(uint, _preorders, _max_preorder, newsize); memset(&_preorders[_max_preorder],0,sizeof(uint)*(newsize-_max_preorder)); _max_preorder = newsize; } } // Check for pre-visited. Zero for NOT visited; non-zero for visited. int is_visited( Node *n ) const { return _preorders[n->_idx]; } // Pre-order numbers are written to the Nodes array as low-bit-set values. void set_preorder_visited( Node *n, int pre_order ) { assert( !is_visited( n ), "already set" ); _preorders[n->_idx] = (pre_order<<1); }; // Return pre-order number. int get_preorder( Node *n ) const { assert( is_visited(n), "" ); return _preorders[n->_idx]>>1; // Check for being post-visited. // Should be previsited already (checked with assert(is_visited(n))). int is_postvisited( Node *n ) const { assert( is_visited(n), "" ); return _preorders[n->_idx]&1; // Mark as post visited void set_postvisited( Node *n ) { assert( !is_postvisited( n ), "" ); _preorders[n->_idx] |= 1; public: // Set/get control node out. Set lower bit to distinguish from IdealLoopTree // Returns true if "n" is a data node, false if it's a control node. bool has_ctrl( Node *n ) const { return ((intptr_t)_nodes[n->_idx]) & 1; } private: // clear out dead code after build_loop_late Node_List _deadlist; // Support for faster execution of get_late_ctrl()/dom_lca() // when a node has many uses and dominator depth is deep. GrowableArray<jlong> _dom_lca_tags; uint _dom_lca_tags_round; void init_dom_lca_tags(); // Helper for debugging bad dominance relationships bool verify_dominance(Node* n, Node* use, Node* LCA, Node* early); Node* compute_lca_of_uses(Node* n, Node* early, bool verify = false); // Inline wrapper for frequent cases: // 1) only one use // 2) a use is the same as the current LCA passed as 'n1' Node *dom_lca_for_get_late_ctrl( Node *lca, Node *n, Node *tag ) { assert( n->is_CFG(), "" ); // Fast-path NULL lca if( lca != NULL && lca != n ) { assert( lca->is_CFG(), "" ); // find LCA of all uses n = dom_lca_for_get_late_ctrl_internal( lca, n, tag ); } return find_non_split_ctrl(n); } Node *dom_lca_for_get_late_ctrl_internal( Node *lca, Node *n, Node *tag ); // Helper function for directing control inputs away from CFG split points. Node *find_non_split_ctrl( Node *ctrl ) const { if (ctrl != NULL) { if (ctrl->is_MultiBranch()) { ctrl = ctrl->in(0); } assert(ctrl->is_CFG(), "CFG"); } return ctrl; } Node* cast_incr_before_loop(Node* incr, Node* ctrl, Node* loop); #ifdef ASSERT void ensure_zero_trip_guard_proj(Node* node, bool is_main_loop); #endif void copy_skeleton_predicates_to_main_loop_helper(Node* predicate, Node* init, Node* s uint dd_main_head, const uint idx_before_pre_post, const uint idx_after_post_before_pre Node* zero_trip_guard_proj_main, Node* zero_trip_guard_proj_post, const Node_List &old_new); void copy_skeleton_predicates_to_main_loop(CountedLoopNode* pre_head, Node* init, Nod uint dd_main_head, const uint idx_before_pre_post, const uint idx_after_post_before_pre Node* zero_trip_guard_proj_main, Node* zero_trip_guard_proj_post, const Node_List &old_new); Node* clone_skeleton_predicate_and_initialize(Node* iff, Node* new_init, Node* new_str IdealLoopTree* outer_loop, Node* input_proj); Node* clone_skeleton_predicate_bool(Node* iff, Node* new_init, Node* new_stride, Node* c static bool skeleton_predicate_has_opaque(IfNode* iff); static void count_opaque_loop_nodes(Node* n, uint& init, uint& stride); static bool subgraph_has_opaque(Node* n); static void get_skeleton_predicates(Node* predicate, Unique_Node_List& list, bool g void update_main_loop_skeleton_predicates(Node* ctrl, CountedLoopNode* loop_head, Nod void copy_skeleton_predicates_to_post_loop(LoopNode* main_loop_head, CountedLoopNod void initialize_skeleton_predicates_for_peeled_loop(ProjNode* predicate, LoopNode* o Node* init, Node* stride, IdealLoopTree* outer_loop, const uint idx_before_clone, const Node_List& old_new); void insert_loop_limit_check(ProjNode* limit_check_proj, Node* cmp_limit, Node* bol); #ifdef ASSERT bool only_has_infinite_loops(); #endif void log_loop_tree(); public: PhaseIterGVN &igvn() const { return _igvn; } bool has_node( Node* n ) const { guarantee(n != NULL, "No Node."); return _nodes[n->_idx] != NULL; } // check if transform created new nodes that need _ctrl recorded Node *get_late_ctrl( Node *n, Node *early ); Node *get_early_ctrl( Node *n ); Node *get_early_ctrl_for_expensive(Node *n, Node* earliest); void set_early_ctrl(Node* n, bool update_body); void set_subtree_ctrl(Node* n, bool update_body); void set_ctrl( Node *n, Node *ctrl ) { assert( !has_node(n) || has_ctrl(n), "" ); assert( ctrl->in(0), "cannot set dead control node" ); assert( ctrl == find_non_split_ctrl(ctrl), "must set legal crtl" ); _nodes.map( n->_idx, (Node*)((intptr_t)ctrl + 1) ); } // Set control and update loop membership void set_ctrl_and_loop(Node* n, Node* ctrl) { IdealLoopTree* old_loop = get_loop(get_ctrl(n)); IdealLoopTree* new_loop = get_loop(ctrl); if (old_loop != new_loop) { if (old_loop->_child == NULL) old_loop->_body.yank(n); if (new_loop->_child == NULL) new_loop->_body.push(n); } set_ctrl(n, ctrl); } // Control nodes can be replaced or subsumed. During this pass they // get their replacement Node in slot 1. Instead of updating the block // location of all Nodes in the subsumed block, we lazily do it. As we // pull such a subsumed block out of the array, we write back the final // correct block. Node *get_ctrl( Node *i ) { assert(has_node(i), ""); Node *n = get_ctrl_no_update(i); _nodes.map( i->_idx, (Node*)((intptr_t)n + 1) ); assert(has_node(i) && has_ctrl(i), ""); assert(n == find_non_split_ctrl(n), "must return legal ctrl" ); return n; } // true if CFG node d dominates CFG node n bool is_dominator(Node *d, Node *n); // return get_ctrl for a data node and self(n) for a CFG node Node* ctrl_or_self(Node* n) { if (has_ctrl(n)) return get_ctrl(n); else { assert (n->is_CFG(), "must be a CFG node"); return n; } } Node *get_ctrl_no_update_helper(Node *i) const { assert(has_ctrl(i), "should be control, not loop"); return (Node*)(((intptr_t)_nodes[i->_idx]) & ~1); } Node *get_ctrl_no_update(Node *i) const { assert( has_ctrl(i), "" ); Node *n = get_ctrl_no_update_helper(i); if (!n->in(0)) { // Skip dead CFG nodes do { n = get_ctrl_no_update_helper(n); } while (!n->in(0)); n = find_non_split_ctrl(n); } return n; } // Check for loop being set // "n" must be a control node. Returns true if "n" is known to be in a loop. bool has_loop( Node *n ) const { assert(!has_node(n) || !has_ctrl(n), ""); return has_node(n); } // Set loop void set_loop( Node *n, IdealLoopTree *loop ) { _nodes.map(n->_idx, (Node*)loop); } // Lazy-dazy update of 'get_ctrl' and 'idom_at' mechanisms. Replace // the 'old_node' with 'new_node'. Kill old-node. Add a reference // from old_node to new_node to support the lazy update. Reference // replaces loop reference, since that is not needed for dead node. void lazy_update(Node *old_node, Node *new_node) { assert(old_node != new_node, "no cycles please"); // Re-use the side array slot for this node to provide the // forwarding pointer. _nodes.map(old_node->_idx, (Node*)((intptr_t)new_node + 1)); } void lazy_replace(Node *old_node, Node *new_node) { _igvn.replace_node(old_node, new_node); lazy_update(old_node, new_node); } private: // Place 'n' in some loop nest, where 'n' is a CFG node void build_loop_tree(); int build_loop_tree_impl( Node *n, int pre_order ); // Insert loop into the existing loop tree. 'innermost' is a leaf of the // loop tree, not the root. IdealLoopTree *sort( IdealLoopTree *loop, IdealLoopTree *innermost ); // Place Data nodes in some loop nest void build_loop_early( VectorSet &visited, Node_List &worklist, Node_Stack &nstack ); void build_loop_late ( VectorSet &visited, Node_List &worklist, Node_Stack &nstack ); void build_loop_late_post_work(Node* n, bool pinned); void build_loop_late_post(Node* n); void verify_strip_mined_scheduling(Node *n, Node* least); // Array of immediate dominance info for each CFG node indexed by node idx private: uint _idom_size; Node **_idom; // Array of immediate dominators uint *_dom_depth; // Used for fast LCA test GrowableArray<uint>* _dom_stk; // For recomputation of dom depth LoopOptsMode _mode; // build the loop tree and perform any requested optimizations void build_and_optimize(); // Dominators for the sea of nodes void Dominators(); // Compute the Ideal Node to Loop mapping PhaseIdealLoop(PhaseIterGVN& igvn, LoopOptsMode mode) : PhaseTransform(Ideal_Loop), _igvn(igvn), _verify_me(nullptr), _verify_only(false), _mode(mode), _nodes_required(UINT_MAX) { assert(mode != LoopOptsVerify, "wrong constructor to verify IdealLoop"); build_and_optimize(); } #ifndef PRODUCT // Verify that verify_me made the same decisions as a fresh run // or only verify that the graph is valid if verify_me is null. PhaseIdealLoop(PhaseIterGVN& igvn, const PhaseIdealLoop* verify_me = nullptr) : PhaseTransform(Ideal_Loop), _igvn(igvn), _verify_me(verify_me), _verify_only(verify_me == nullptr), _mode(LoopOptsVerify), _nodes_required(UINT_MAX) { build_and_optimize(); } #endif public: Node* idom_no_update(Node* d) const { return idom_no_update(d->_idx); } Node* idom_no_update(uint didx) const { assert(didx < _idom_size, "oob"); Node* n = _idom[didx]; assert(n != NULL,"Bad immediate dominator info."); while (n->in(0) == NULL) { // Skip dead CFG nodes n = (Node*)(((intptr_t)_nodes[n->_idx]) & ~1); assert(n != NULL,"Bad immediate dominator info."); } return n; } Node *idom(Node* d) const { return idom(d->_idx); } Node *idom(uint didx) const { Node *n = idom_no_update(didx); _idom[didx] = n; // Lazily remove dead CFG nodes from table. return n; } uint dom_depth(Node* d) const { guarantee(d != NULL, "Null dominator info."); guarantee(d->_idx < _idom_size, ""); return _dom_depth[d->_idx]; } void set_idom(Node* d, Node* n, uint dom_depth); // Locally compute IDOM using dom_lca call Node *compute_idom( Node *region ) const; // Recompute dom_depth void recompute_dom_depth(); // Is safept not required by an outer loop? bool is_deleteable_safept(Node* sfpt); // Replace parallel induction variable (parallel to trip counter) void replace_parallel_iv(IdealLoopTree *loop); Node *dom_lca( Node *n1, Node *n2 ) const { return find_non_split_ctrl(dom_lca_internal(n1, n2)); } Node *dom_lca_internal( Node *n1, Node *n2 ) const; // Build and verify the loop tree without modifying the graph. This // is useful to verify that all inputs properly dominate their uses. static void verify(PhaseIterGVN& igvn) { #ifdef ASSERT ResourceMark rm; Compile::TracePhase tp("idealLoopVerify", &timers[_t_idealLoopVerify]); PhaseIdealLoop v(igvn); #endif } // Recommended way to use PhaseIdealLoop. // Run PhaseIdealLoop in some mode and allocates a local scope for memory allocations. static void optimize(PhaseIterGVN &igvn, LoopOptsMode mode) { ResourceMark rm; PhaseIdealLoop v(igvn, mode); Compile* C = Compile::current(); if (!C->failing()) { // Cleanup any modified bits igvn.optimize(); v.log_loop_tree(); } } // True if the method has at least 1 irreducible loop bool _has_irreducible_loops; // Per-Node transform virtual Node* transform(Node* n) { return NULL; } Node* loop_exit_control(Node* x, IdealLoopTree* loop); Node* loop_exit_test(Node* back_control, IdealLoopTree* loop, Node*& incr, Node*&&nbs Node* loop_iv_incr(Node* incr, Node* x, IdealLoopTree* loop, Node*& phi_incr); Node* loop_iv_stride(Node* incr, IdealLoopTree* loop, Node*& xphi); PhiNode* loop_iv_phi(Node* xphi, Node* phi_incr, Node* x, IdealLoopTree* loop); bool is_counted_loop(Node* x, IdealLoopTree*&loop, BasicType iv_bt); Node* loop_nest_replace_iv(Node* iv_to_replace, Node* inner_iv, Node* outer_phi, Node* i bool create_loop_nest(IdealLoopTree* loop, Node_List &old_new); #ifdef ASSERT bool convert_to_long_loop(Node* cmp, Node* phi, IdealLoopTree* loop); #endif void add_empty_predicate(Deoptimization::DeoptReason reason, Node* inner_head, IdealL SafePointNode* find_safepoint(Node* back_control, Node* x, IdealLoopTree* loop); IdealLoopTree* insert_outer_loop(IdealLoopTree* loop, LoopNode* outer_l, Node* outer_i IdealLoopTree* create_outer_strip_mined_loop(BoolNode *test, Node *cmp, Node *init_con IdealLoopTree* loop, float cl_prob, float le_fcnt, Node*& entry_control, Node*& iffalse); Node* exact_limit( IdealLoopTree *loop ); // Return a post-walked LoopNode IdealLoopTree *get_loop( Node *n ) const { // Dead nodes have no loop, so return the top level loop instead if (!has_node(n)) return _ltree_root; assert(!has_ctrl(n), ""); return (IdealLoopTree*)_nodes[n->_idx]; } IdealLoopTree* ltree_root() const { return _ltree_root; } // Is 'n' a (nested) member of 'loop'? int is_member( const IdealLoopTree *loop, Node *n ) const { return loop->is_member(get_loop(n)); } // This is the basic building block of the loop optimizations. It clones an // entire loop body. It makes an old_new loop body mapping; with this // mapping you can find the new-loop equivalent to an old-loop node. All // new-loop nodes are exactly equal to their old-loop counterparts, all // edges are the same. All exits from the old-loop now have a RegionNode // that merges the equivalent new-loop path. This is true even for the // normal "loop-exit" condition. All uses of loop-invariant old-loop values // now come from (one or more) Phis that merge their new-loop equivalents. // Parameter side_by_side_idom: // When side_by_size_idom is NULL, the dominator tree is constructed for // the clone loop to dominate the original. Used in construction of // pre-main-post loop sequence. // When nonnull, the clone and original are side-by-side, both are // dominated by the passed in side_by_side_idom node. Used in // construction of unswitched loops. enum CloneLoopMode { IgnoreStripMined = 0, // Only clone inner strip mined loop CloneIncludesStripMined = 1, // clone both inner and outer strip mined loops ControlAroundStripMined = 2 // Only clone inner strip mined loop, // result control flow branches // either to inner clone or outer // strip mined loop. }; void clone_loop( IdealLoopTree *loop, Node_List &old_new, int dom_depth, CloneLoopMode mode, Node* side_by_side_idom = NULL); void clone_loop_handle_data_uses(Node* old, Node_List &old_new, IdealLoopTree* loop, IdealLoopTree* companion_loop, Node_List*& split_if_set, Node_List*& split_bool_set, Node_List*& split_cex_set, Node_List& worklist, uint new_counter, CloneLoopMode mode); void clone_outer_loop(LoopNode* head, CloneLoopMode mode, IdealLoopTree *loop, IdealLoopTree* outer_loop, int dd, Node_List &old_new, Node_List& extra_data_nodes); // If we got the effect of peeling, either by actually peeling or by // making a pre-loop which must execute at least once, we can remove // all loop-invariant dominated tests in the main body. void peeled_dom_test_elim( IdealLoopTree *loop, Node_List &old_new ); // Generate code to do a loop peel for the given loop (and body). // old_new is a temp array. void do_peeling( IdealLoopTree *loop, Node_List &old_new ); // Add pre and post loops around the given loop. These loops are used // during RCE, unrolling and aligning loops. void insert_pre_post_loops( IdealLoopTree *loop, Node_List &old_new, bool peel_only ); // Add post loop after the given loop. Node *insert_post_loop(IdealLoopTree* loop, Node_List& old_new, CountedLoopNode* main_head, CountedLoopEndNode* main_end, Node*& incr, Node* limit, CountedLoopNode*& post_head); // Add an RCE'd post loop which we will multi-version adapt for run time test path usage void insert_scalar_rced_post_loop( IdealLoopTree *loop, Node_List &old_new ); // Add a vector post loop between a vector main loop and the current post loop void insert_vector_post_loop(IdealLoopTree *loop, Node_List &old_new); // If Node n lives in the back_ctrl block, we clone a private version of n // in preheader_ctrl block and return that, otherwise return n. Node *clone_up_backedge_goo( Node *back_ctrl, Node *preheader_ctrl, Node *n, VectorSet &visited,&nb // Take steps to maximally unroll the loop. Peel any odd iterations, then // unroll to do double iterations. The next round of major loop transforms // will repeat till the doubled loop body does all remaining iterations in 1 // pass. void do_maximally_unroll( IdealLoopTree *loop, Node_List &old_new ); // Unroll the loop body one step - make each trip do 2 iterations. void do_unroll( IdealLoopTree *loop, Node_List &old_new, bool adjust_min_trip ); // Mark vector reduction candidates before loop unrolling void mark_reductions( IdealLoopTree *loop ); // Return true if exp is a constant times an induction var bool is_scaled_iv(Node* exp, Node* iv, BasicType bt, jlong* p_scale, bool* p_short_scale, i bool is_iv(Node* exp, Node* iv, BasicType bt); // Return true if exp is a scaled induction var plus (or minus) constant bool is_scaled_iv_plus_offset(Node* exp, Node* iv, BasicType bt, jlong* p_scale, Node** p_ bool is_scaled_iv_plus_offset(Node* exp, Node* iv, int* p_scale, Node** p_offset) { jlong long_scale; if (is_scaled_iv_plus_offset(exp, iv, T_INT, &long_scale, p_offset)) { int int_scale = checked_cast<int>(long_scale); if (p_scale != NULL) { *p_scale = int_scale; } return true; } return false; } // Helper for finding more complex matches to is_scaled_iv_plus_offset. bool is_scaled_iv_plus_extra_offset(Node* exp1, Node* offset2, Node* iv, BasicType bt, jlong* p_scale, Node** p_offset, bool* p_short_scale, int depth); // Create a new if above the uncommon_trap_if_pattern for the predicate to be promoted ProjNode* create_new_if_for_predicate(ProjNode* cont_proj, Node* new_entry, Deoptimiz int opcode, bool rewire_uncommon_proj_phi_inputs = false, bool if_cont_is_true_proj = true); private: // Helper functions for create_new_if_for_predicate() void set_ctrl_of_nodes_with_same_ctrl(Node* node, ProjNode* old_ctrl, Node* new_ctrl); Unique_Node_List find_nodes_with_same_ctrl(Node* node, const ProjNode* ctrl); Node* clone_nodes_with_same_ctrl(Node* node, ProjNode* old_ctrl, Node* new_ctrl); Dict clone_nodes(const Node_List& list_to_clone); void rewire_cloned_nodes_to_ctrl(const ProjNode* old_ctrl, Node* new_ctrl, const Node_L const Dict& old_new_mapping); void rewire_inputs_of_clones_to_clones(Node* new_ctrl, Node* clone, const Dict& old public: void register_control(Node* n, IdealLoopTree *loop, Node* pred, bool update_body = true); static Node* skip_all_loop_predicates(Node* entry); static Node* skip_loop_predicates(Node* entry); static ProjNode* next_predicate(ProjNode* predicate); // Find a good location to insert a predicate static ProjNode* find_predicate_insertion_point(Node* start_c, Deoptimization::Deopt class Predicates { public: // given loop entry, find all predicates above loop Predicates(Node* entry); // Proj of empty loop limit check predicate ProjNode* loop_limit_check() { return _loop_limit_check; } // Proj of empty profile predicate ProjNode* profile_predicate() { return _profile_predicate; } // Proj of empty predicate ProjNode* predicate() { return _predicate; } // First control node above all predicates Node* skip_all() { return _entry_to_all_predicates; } private: ProjNode*_loop_limit_check = nullptr; ProjNode* _profile_predicate = nullptr; ProjNode* _predicate = nullptr; Node* _entry_to_all_predicates = nullptr; }; // Find a predicate static Node* find_predicate(Node* entry); // Construct a range check for a predicate if BoolNode* rc_predicate(IdealLoopTree *loop, Node* ctrl, int scale, Node* offset, Node* init, Node* limit, jint stride, Node* range, bool upper, bool &overflow, bool negate); // Implementation of the loop predication to promote checks outside the loop bool loop_predication_impl(IdealLoopTree *loop); bool loop_predication_impl_helper(IdealLoopTree *loop, ProjNode* proj, ProjNode *predi CountedLoopNode *cl, ConNode* zero, Invariance& invar, Deoptimization::DeoptReason reason); bool loop_predication_should_follow_branches(IdealLoopTree *loop, ProjNode *predicat void loop_predication_follow_branches(Node *c, IdealLoopTree *loop, float loop_trip_cn PathFrequency& pf, Node_Stack& stack, VectorSet& seen, Node_List& if_proj_list); ProjNode* insert_initial_skeleton_predicate(IfNode* iff, IdealLoopTree *loop, ProjNode* proj, ProjNode *predicate_proj, ProjNode* upper_bound_proj, int scale, Node* offset, Node* init, Node* limit, jint stride, Node* rng, bool& overflow, Deoptimization::DeoptReason reason); Node* add_range_check_predicate(IdealLoopTree* loop, CountedLoopNode* cl, Node* predicate_proj, int scale_con, Node* offset, Node* limit, jint stride_con, Node* value); // Helper function to collect predicate for eliminating the useless ones void collect_potentially_useful_predicates(IdealLoopTree *loop, Unique_Node_List &predicate_opaque1); void eliminate_useless_predicates(); // Change the control input of expensive nodes to allow commoning by // IGVN when it is guaranteed to not result in a more frequent // execution of the expensive node. Return true if progress. bool process_expensive_nodes(); // Check whether node has become unreachable bool is_node_unreachable(Node *n) const { return !has_node(n) || n->is_unreachable(_igvn); } // Eliminate range-checks and other trip-counter vs loop-invariant tests. int do_range_check( IdealLoopTree *loop, Node_List &old_new ); // Check to see if do_range_check(...) cleaned the main loop of range-checks void has_range_checks(IdealLoopTree *loop); // Process post loops which have range checks and try to build a multi-version // guard to safely determine if we can execute the post loop which was RCE'd. bool multi_version_post_loops(IdealLoopTree *rce_loop, IdealLoopTree *legacy_loop); // Cause the rce'd post loop to optimized away, this happens if we cannot complete multiverioni void poison_rce_post_loop(IdealLoopTree *rce_loop); // Create a slow version of the loop by cloning the loop // and inserting an if to select fast-slow versions. // Return the inserted if. IfNode* create_slow_version_of_loop(IdealLoopTree *loop, Node_List &old_new, IfNode* unswitch_iff, CloneLoopMode mode); // Clone a loop and return the clone head (clone_loop_head). // Added nodes include int(1), int(0) - disconnected, If, IfTrue, IfFalse, // This routine was created for usage in CountedLoopReserveKit. // // int(1) -> If -> IfTrue -> original_loop_head // | // V // IfFalse -> clone_loop_head (returned by function pointer) // LoopNode* create_reserve_version_of_loop(IdealLoopTree *loop, CountedLoopReserveKit // Clone loop with an invariant test (that does not exit) and // insert a clone of the test that selects which version to // execute. void do_unswitching (IdealLoopTree *loop, Node_List &old_new); // Find candidate "if" for unswitching IfNode* find_unswitching_candidate(const IdealLoopTree *loop) const; // Range Check Elimination uses this function! // Constrain the main loop iterations so the affine function: // low_limit <= scale_con * I + offset < upper_limit // always holds true. That is, either increase the number of iterations in // the pre-loop or the post-loop until the condition holds true in the main // loop. Scale_con, offset and limit are all loop invariant. void add_constraint(jlong stride_con, jlong scale_con, Node* offset, Node* low_limit, Nod // Helper function for add_constraint(). Node* adjust_limit(bool reduce, Node* scale, Node* offset, Node* rc_limit, Node* old_limit // Partially peel loop up through last_peel node. bool partial_peel( IdealLoopTree *loop, Node_List &old_new ); bool duplicate_loop_backedge(IdealLoopTree *loop, Node_List &old_new); // Create a scheduled list of nodes control dependent on ctrl set. void scheduled_nodelist( IdealLoopTree *loop, VectorSet& ctrl, Node_List &sched ); // Has a use in the vector set bool has_use_in_set( Node* n, VectorSet& vset ); // Has use internal to the vector set (ie. not in a phi at the loop head) bool has_use_internal_to_set( Node* n, VectorSet& vset, IdealLoopTree *loop ); // clone "n" for uses that are outside of loop int clone_for_use_outside_loop( IdealLoopTree *loop, Node* n, Node_List& worklist ); // clone "n" for special uses that are in the not_peeled region void clone_for_special_use_inside_loop( IdealLoopTree *loop, Node* n, VectorSet& not_peel, Node_List& sink_list, Node_List& worklist ); // Insert phi(lp_entry_val, back_edge_val) at use->in(idx) for loop lp if phi does not already void insert_phi_for_loop( Node* use, uint idx, Node* lp_entry_val, Node* back_edge_val, Lo #ifdef ASSERT // Validate the loop partition sets: peel and not_peel bool is_valid_loop_partition( IdealLoopTree *loop, VectorSet& peel, Node_List& // Ensure that uses outside of loop are of the right form bool is_valid_clone_loop_form( IdealLoopTree *loop, Node_List& peel_list, uint orig_exit_idx, uint clone_exit_idx); bool is_valid_clone_loop_exit_use( IdealLoopTree *loop, Node* use, uint exit_idx); #endif // Returns nonzero constant stride if-node is a possible iv test (otherwise returns zero.) int stride_of_possible_iv( Node* iff ); bool is_possible_iv_test( Node* iff ) { return stride_of_possible_iv(iff) != 0; } // Return the (unique) control output node that's in the loop (if it exists.) Node* stay_in_loop( Node* n, IdealLoopTree *loop); // Insert a signed compare loop exit cloned from an unsigned compare. IfNode* insert_cmpi_loop_exit(IfNode* if_cmpu, IdealLoopTree *loop); void remove_cmpi_loop_exit(IfNode* if_cmp, IdealLoopTree *loop); // Utility to register node "n" with PhaseIdealLoop void register_node(Node* n, IdealLoopTree *loop, Node* pred, int ddepth); // Utility to create an if-projection ProjNode* proj_clone(ProjNode* p, IfNode* iff); // Force the iff control output to be the live_proj Node* short_circuit_if(IfNode* iff, ProjNode* live_proj); // Insert a region before an if projection RegionNode* insert_region_before_proj(ProjNode* proj); // Insert a new if before an if projection ProjNode* insert_if_before_proj(Node* left, bool Signed, BoolTest::mask relop, Node* rig // Passed in a Phi merging (recursively) some nearly equivalent Bool/Cmps. // "Nearly" because all Nodes have been cloned from the original in the loop, // but the fall-in edges to the Cmp are different. Clone bool/Cmp pairs // through the Phi recursively, and return a Bool. Node* clone_iff(PhiNode* phi); CmpNode* clone_bool(PhiNode* phi); // Rework addressing expressions to get the most loop-invariant stuff // moved out. We'd like to do all associative operators, but it's especially // important (common) to do address expressions. Node* remix_address_expressions(Node* n); Node* remix_address_expressions_add_left_shift(Node* n, IdealLoopTree* n_loop, Node* n // Convert add to muladd to generate MuladdS2I under certain criteria Node * convert_add_to_muladd(Node * n); // Attempt to use a conditional move instead of a phi/branch Node *conditional_move( Node *n ); // Check for aggressive application of 'split-if' optimization, // using basic block level info. void split_if_with_blocks ( VectorSet &visited, Node_Stack &nstack); Node *split_if_with_blocks_pre ( Node *n ); --> -------------------- --> maximum size reached --> -------------------- ¤ Dauer der Verarbeitung: 0.183 Sekunden (vorverarbeitet) ¤ |
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