--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/opto/cfgnode.hpp Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,609 @@
+/*
+ * Copyright (c) 1997, 2015, 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_VM_OPTO_CFGNODE_HPP
+#define SHARE_VM_OPTO_CFGNODE_HPP
+
+#include "opto/multnode.hpp"
+#include "opto/node.hpp"
+#include "opto/opcodes.hpp"
+#include "opto/type.hpp"
+
+// Portions of code courtesy of Clifford Click
+
+// Optimization - Graph Style
+
+class Matcher;
+class Node;
+class RegionNode;
+class TypeNode;
+class PhiNode;
+class GotoNode;
+class MultiNode;
+class MultiBranchNode;
+class IfNode;
+class PCTableNode;
+class JumpNode;
+class CatchNode;
+class NeverBranchNode;
+class ProjNode;
+class CProjNode;
+class IfTrueNode;
+class IfFalseNode;
+class CatchProjNode;
+class JProjNode;
+class JumpProjNode;
+class SCMemProjNode;
+class PhaseIdealLoop;
+
+//------------------------------RegionNode-------------------------------------
+// The class of RegionNodes, which can be mapped to basic blocks in the
+// program. Their inputs point to Control sources. PhiNodes (described
+// below) have an input point to a RegionNode. Merged data inputs to PhiNodes
+// correspond 1-to-1 with RegionNode inputs. The zero input of a PhiNode is
+// the RegionNode, and the zero input of the RegionNode is itself.
+class RegionNode : public Node {
+public:
+ // Node layout (parallels PhiNode):
+ enum { Region, // Generally points to self.
+ Control // Control arcs are [1..len)
+ };
+
+ RegionNode( uint required ) : Node(required) {
+ init_class_id(Class_Region);
+ init_req(0,this);
+ }
+
+ Node* is_copy() const {
+ const Node* r = _in[Region];
+ if (r == NULL)
+ return nonnull_req();
+ return NULL; // not a copy!
+ }
+ PhiNode* has_phi() const; // returns an arbitrary phi user, or NULL
+ PhiNode* has_unique_phi() const; // returns the unique phi user, or NULL
+ // Is this region node unreachable from root?
+ bool is_unreachable_region(PhaseGVN *phase) const;
+ virtual int Opcode() const;
+ virtual bool pinned() const { return (const Node *)in(0) == this; }
+ virtual bool is_CFG () const { return true; }
+ virtual uint hash() const { return NO_HASH; } // CFG nodes do not hash
+ virtual bool depends_only_on_test() const { return false; }
+ virtual const Type *bottom_type() const { return Type::CONTROL; }
+ virtual const Type* Value(PhaseGVN* phase) const;
+ virtual Node* Identity(PhaseGVN* phase);
+ virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
+ virtual const RegMask &out_RegMask() const;
+ bool try_clean_mem_phi(PhaseGVN *phase);
+};
+
+//------------------------------JProjNode--------------------------------------
+// jump projection for node that produces multiple control-flow paths
+class JProjNode : public ProjNode {
+ public:
+ JProjNode( Node* ctrl, uint idx ) : ProjNode(ctrl,idx) {}
+ virtual int Opcode() const;
+ virtual bool is_CFG() const { return true; }
+ virtual uint hash() const { return NO_HASH; } // CFG nodes do not hash
+ virtual const Node* is_block_proj() const { return in(0); }
+ virtual const RegMask& out_RegMask() const;
+ virtual uint ideal_reg() const { return 0; }
+};
+
+//------------------------------PhiNode----------------------------------------
+// PhiNodes merge values from different Control paths. Slot 0 points to the
+// controlling RegionNode. Other slots map 1-for-1 with incoming control flow
+// paths to the RegionNode. For speed reasons (to avoid another pass) we
+// can turn PhiNodes into copys in-place by NULL'ing out their RegionNode
+// input in slot 0.
+class PhiNode : public TypeNode {
+ const TypePtr* const _adr_type; // non-null only for Type::MEMORY nodes.
+ // The following fields are only used for data PhiNodes to indicate
+ // that the PhiNode represents the value of a known instance field.
+ int _inst_mem_id; // Instance memory id (node index of the memory Phi)
+ const int _inst_id; // Instance id of the memory slice.
+ const int _inst_index; // Alias index of the instance memory slice.
+ // Array elements references have the same alias_idx but different offset.
+ const int _inst_offset; // Offset of the instance memory slice.
+ // Size is bigger to hold the _adr_type field.
+ virtual uint hash() const; // Check the type
+ virtual uint cmp( const Node &n ) const;
+ virtual uint size_of() const { return sizeof(*this); }
+
+ // Determine if CMoveNode::is_cmove_id can be used at this join point.
+ Node* is_cmove_id(PhaseTransform* phase, int true_path);
+
+public:
+ // Node layout (parallels RegionNode):
+ enum { Region, // Control input is the Phi's region.
+ Input // Input values are [1..len)
+ };
+
+ PhiNode( Node *r, const Type *t, const TypePtr* at = NULL,
+ const int imid = -1,
+ const int iid = TypeOopPtr::InstanceTop,
+ const int iidx = Compile::AliasIdxTop,
+ const int ioffs = Type::OffsetTop )
+ : TypeNode(t,r->req()),
+ _adr_type(at),
+ _inst_mem_id(imid),
+ _inst_id(iid),
+ _inst_index(iidx),
+ _inst_offset(ioffs)
+ {
+ init_class_id(Class_Phi);
+ init_req(0, r);
+ verify_adr_type();
+ }
+ // create a new phi with in edges matching r and set (initially) to x
+ static PhiNode* make( Node* r, Node* x );
+ // extra type arguments override the new phi's bottom_type and adr_type
+ static PhiNode* make( Node* r, Node* x, const Type *t, const TypePtr* at = NULL );
+ // create a new phi with narrowed memory type
+ PhiNode* slice_memory(const TypePtr* adr_type) const;
+ PhiNode* split_out_instance(const TypePtr* at, PhaseIterGVN *igvn) const;
+ // like make(r, x), but does not initialize the in edges to x
+ static PhiNode* make_blank( Node* r, Node* x );
+
+ // Accessors
+ RegionNode* region() const { Node* r = in(Region); assert(!r || r->is_Region(), ""); return (RegionNode*)r; }
+
+ Node* is_copy() const {
+ // The node is a real phi if _in[0] is a Region node.
+ DEBUG_ONLY(const Node* r = _in[Region];)
+ assert(r != NULL && r->is_Region(), "Not valid control");
+ return NULL; // not a copy!
+ }
+
+ bool is_tripcount() const;
+
+ // Determine a unique non-trivial input, if any.
+ // Ignore casts if it helps. Return NULL on failure.
+ Node* unique_input(PhaseTransform *phase, bool uncast);
+ Node* unique_input(PhaseTransform *phase) {
+ Node* uin = unique_input(phase, false);
+ if (uin == NULL) {
+ uin = unique_input(phase, true);
+ }
+ return uin;
+ }
+
+ // Check for a simple dead loop.
+ enum LoopSafety { Safe = 0, Unsafe, UnsafeLoop };
+ LoopSafety simple_data_loop_check(Node *in) const;
+ // Is it unsafe data loop? It becomes a dead loop if this phi node removed.
+ bool is_unsafe_data_reference(Node *in) const;
+ int is_diamond_phi(bool check_control_only = false) const;
+ virtual int Opcode() const;
+ virtual bool pinned() const { return in(0) != 0; }
+ virtual const TypePtr *adr_type() const { verify_adr_type(true); return _adr_type; }
+
+ void set_inst_mem_id(int inst_mem_id) { _inst_mem_id = inst_mem_id; }
+ const int inst_mem_id() const { return _inst_mem_id; }
+ const int inst_id() const { return _inst_id; }
+ const int inst_index() const { return _inst_index; }
+ const int inst_offset() const { return _inst_offset; }
+ bool is_same_inst_field(const Type* tp, int mem_id, int id, int index, int offset) {
+ return type()->basic_type() == tp->basic_type() &&
+ inst_mem_id() == mem_id &&
+ inst_id() == id &&
+ inst_index() == index &&
+ inst_offset() == offset &&
+ type()->higher_equal(tp);
+ }
+
+ virtual const Type* Value(PhaseGVN* phase) const;
+ virtual Node* Identity(PhaseGVN* phase);
+ virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
+ virtual const RegMask &out_RegMask() const;
+ virtual const RegMask &in_RegMask(uint) const;
+#ifndef PRODUCT
+ virtual void related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const;
+ virtual void dump_spec(outputStream *st) const;
+#endif
+#ifdef ASSERT
+ void verify_adr_type(VectorSet& visited, const TypePtr* at) const;
+ void verify_adr_type(bool recursive = false) const;
+#else //ASSERT
+ void verify_adr_type(bool recursive = false) const {}
+#endif //ASSERT
+};
+
+//------------------------------GotoNode---------------------------------------
+// GotoNodes perform direct branches.
+class GotoNode : public Node {
+public:
+ GotoNode( Node *control ) : Node(control) {}
+ virtual int Opcode() const;
+ virtual bool pinned() const { return true; }
+ virtual bool is_CFG() const { return true; }
+ virtual uint hash() const { return NO_HASH; } // CFG nodes do not hash
+ virtual const Node *is_block_proj() const { return this; }
+ virtual bool depends_only_on_test() const { return false; }
+ virtual const Type *bottom_type() const { return Type::CONTROL; }
+ virtual const Type* Value(PhaseGVN* phase) const;
+ virtual Node* Identity(PhaseGVN* phase);
+ virtual const RegMask &out_RegMask() const;
+
+#ifndef PRODUCT
+ virtual void related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const;
+#endif
+};
+
+//------------------------------CProjNode--------------------------------------
+// control projection for node that produces multiple control-flow paths
+class CProjNode : public ProjNode {
+public:
+ CProjNode( Node *ctrl, uint idx ) : ProjNode(ctrl,idx) {}
+ virtual int Opcode() const;
+ virtual bool is_CFG() const { return true; }
+ virtual uint hash() const { return NO_HASH; } // CFG nodes do not hash
+ virtual const Node *is_block_proj() const { return in(0); }
+ virtual const RegMask &out_RegMask() const;
+ virtual uint ideal_reg() const { return 0; }
+};
+
+//---------------------------MultiBranchNode-----------------------------------
+// This class defines a MultiBranchNode, a MultiNode which yields multiple
+// control values. These are distinguished from other types of MultiNodes
+// which yield multiple values, but control is always and only projection #0.
+class MultiBranchNode : public MultiNode {
+public:
+ MultiBranchNode( uint required ) : MultiNode(required) {
+ init_class_id(Class_MultiBranch);
+ }
+ // returns required number of users to be well formed.
+ virtual int required_outcnt() const = 0;
+};
+
+//------------------------------IfNode-----------------------------------------
+// Output selected Control, based on a boolean test
+class IfNode : public MultiBranchNode {
+ // Size is bigger to hold the probability field. However, _prob does not
+ // change the semantics so it does not appear in the hash & cmp functions.
+ virtual uint size_of() const { return sizeof(*this); }
+
+private:
+ // Helper methods for fold_compares
+ bool cmpi_folds(PhaseIterGVN* igvn);
+ bool is_ctrl_folds(Node* ctrl, PhaseIterGVN* igvn);
+ bool has_shared_region(ProjNode* proj, ProjNode*& success, ProjNode*& fail);
+ bool has_only_uncommon_traps(ProjNode* proj, ProjNode*& success, ProjNode*& fail, PhaseIterGVN* igvn);
+ Node* merge_uncommon_traps(ProjNode* proj, ProjNode* success, ProjNode* fail, PhaseIterGVN* igvn);
+ static void improve_address_types(Node* l, Node* r, ProjNode* fail, PhaseIterGVN* igvn);
+ bool is_cmp_with_loadrange(ProjNode* proj);
+ bool is_null_check(ProjNode* proj, PhaseIterGVN* igvn);
+ bool is_side_effect_free_test(ProjNode* proj, PhaseIterGVN* igvn);
+ void reroute_side_effect_free_unc(ProjNode* proj, ProjNode* dom_proj, PhaseIterGVN* igvn);
+ ProjNode* uncommon_trap_proj(CallStaticJavaNode*& call) const;
+ bool fold_compares_helper(ProjNode* proj, ProjNode* success, ProjNode* fail, PhaseIterGVN* igvn);
+
+protected:
+ ProjNode* range_check_trap_proj(int& flip, Node*& l, Node*& r);
+ Node* Ideal_common(PhaseGVN *phase, bool can_reshape);
+ Node* dominated_by(Node* prev_dom, PhaseIterGVN* igvn);
+ Node* search_identical(int dist);
+
+public:
+
+ // Degrees of branch prediction probability by order of magnitude:
+ // PROB_UNLIKELY_1e(N) is a 1 in 1eN chance.
+ // PROB_LIKELY_1e(N) is a 1 - PROB_UNLIKELY_1e(N)
+#define PROB_UNLIKELY_MAG(N) (1e- ## N ## f)
+#define PROB_LIKELY_MAG(N) (1.0f-PROB_UNLIKELY_MAG(N))
+
+ // Maximum and minimum branch prediction probabilties
+ // 1 in 1,000,000 (magnitude 6)
+ //
+ // Although PROB_NEVER == PROB_MIN and PROB_ALWAYS == PROB_MAX
+ // they are used to distinguish different situations:
+ //
+ // The name PROB_MAX (PROB_MIN) is for probabilities which correspond to
+ // very likely (unlikely) but with a concrete possibility of a rare
+ // contrary case. These constants would be used for pinning
+ // measurements, and as measures for assertions that have high
+ // confidence, but some evidence of occasional failure.
+ //
+ // The name PROB_ALWAYS (PROB_NEVER) is to stand for situations for which
+ // there is no evidence at all that the contrary case has ever occurred.
+
+#define PROB_NEVER PROB_UNLIKELY_MAG(6)
+#define PROB_ALWAYS PROB_LIKELY_MAG(6)
+
+#define PROB_MIN PROB_UNLIKELY_MAG(6)
+#define PROB_MAX PROB_LIKELY_MAG(6)
+
+ // Static branch prediction probabilities
+ // 1 in 10 (magnitude 1)
+#define PROB_STATIC_INFREQUENT PROB_UNLIKELY_MAG(1)
+#define PROB_STATIC_FREQUENT PROB_LIKELY_MAG(1)
+
+ // Fair probability 50/50
+#define PROB_FAIR (0.5f)
+
+ // Unknown probability sentinel
+#define PROB_UNKNOWN (-1.0f)
+
+ // Probability "constructors", to distinguish as a probability any manifest
+ // constant without a names
+#define PROB_LIKELY(x) ((float) (x))
+#define PROB_UNLIKELY(x) (1.0f - (float)(x))
+
+ // Other probabilities in use, but without a unique name, are documented
+ // here for lack of a better place:
+ //
+ // 1 in 1000 probabilities (magnitude 3):
+ // threshold for converting to conditional move
+ // likelihood of null check failure if a null HAS been seen before
+ // likelihood of slow path taken in library calls
+ //
+ // 1 in 10,000 probabilities (magnitude 4):
+ // threshold for making an uncommon trap probability more extreme
+ // threshold for for making a null check implicit
+ // likelihood of needing a gc if eden top moves during an allocation
+ // likelihood of a predicted call failure
+ //
+ // 1 in 100,000 probabilities (magnitude 5):
+ // threshold for ignoring counts when estimating path frequency
+ // likelihood of FP clipping failure
+ // likelihood of catching an exception from a try block
+ // likelihood of null check failure if a null has NOT been seen before
+ //
+ // Magic manifest probabilities such as 0.83, 0.7, ... can be found in
+ // gen_subtype_check() and catch_inline_exceptions().
+
+ float _prob; // Probability of true path being taken.
+ float _fcnt; // Frequency counter
+ IfNode( Node *control, Node *b, float p, float fcnt )
+ : MultiBranchNode(2), _prob(p), _fcnt(fcnt) {
+ init_class_id(Class_If);
+ init_req(0,control);
+ init_req(1,b);
+ }
+ virtual int Opcode() const;
+ virtual bool pinned() const { return true; }
+ virtual const Type *bottom_type() const { return TypeTuple::IFBOTH; }
+ virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
+ virtual const Type* Value(PhaseGVN* phase) const;
+ virtual int required_outcnt() const { return 2; }
+ virtual const RegMask &out_RegMask() const;
+ Node* fold_compares(PhaseIterGVN* phase);
+ static Node* up_one_dom(Node* curr, bool linear_only = false);
+
+ // Takes the type of val and filters it through the test represented
+ // by if_proj and returns a more refined type if one is produced.
+ // Returns NULL is it couldn't improve the type.
+ static const TypeInt* filtered_int_type(PhaseGVN* phase, Node* val, Node* if_proj);
+
+#ifndef PRODUCT
+ virtual void dump_spec(outputStream *st) const;
+ virtual void related(GrowableArray <Node *> *in_rel, GrowableArray <Node *> *out_rel, bool compact) const;
+#endif
+};
+
+class RangeCheckNode : public IfNode {
+private:
+ int is_range_check(Node* &range, Node* &index, jint &offset);
+
+public:
+ RangeCheckNode(Node* control, Node *b, float p, float fcnt)
+ : IfNode(control, b, p, fcnt) {
+ init_class_id(Class_RangeCheck);
+ }
+
+ virtual int Opcode() const;
+ virtual Node* Ideal(PhaseGVN *phase, bool can_reshape);
+};
+
+class IfProjNode : public CProjNode {
+public:
+ IfProjNode(IfNode *ifnode, uint idx) : CProjNode(ifnode,idx) {}
+ virtual Node* Identity(PhaseGVN* phase);
+
+protected:
+ // Type of If input when this branch is always taken
+ virtual bool always_taken(const TypeTuple* t) const = 0;
+
+#ifndef PRODUCT
+public:
+ virtual void related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const;
+#endif
+};
+
+class IfTrueNode : public IfProjNode {
+public:
+ IfTrueNode( IfNode *ifnode ) : IfProjNode(ifnode,1) {
+ init_class_id(Class_IfTrue);
+ }
+ virtual int Opcode() const;
+
+protected:
+ virtual bool always_taken(const TypeTuple* t) const { return t == TypeTuple::IFTRUE; }
+};
+
+class IfFalseNode : public IfProjNode {
+public:
+ IfFalseNode( IfNode *ifnode ) : IfProjNode(ifnode,0) {
+ init_class_id(Class_IfFalse);
+ }
+ virtual int Opcode() const;
+
+protected:
+ virtual bool always_taken(const TypeTuple* t) const { return t == TypeTuple::IFFALSE; }
+};
+
+
+//------------------------------PCTableNode------------------------------------
+// Build an indirect branch table. Given a control and a table index,
+// control is passed to the Projection matching the table index. Used to
+// implement switch statements and exception-handling capabilities.
+// Undefined behavior if passed-in index is not inside the table.
+class PCTableNode : public MultiBranchNode {
+ virtual uint hash() const; // Target count; table size
+ virtual uint cmp( const Node &n ) const;
+ virtual uint size_of() const { return sizeof(*this); }
+
+public:
+ const uint _size; // Number of targets
+
+ PCTableNode( Node *ctrl, Node *idx, uint size ) : MultiBranchNode(2), _size(size) {
+ init_class_id(Class_PCTable);
+ init_req(0, ctrl);
+ init_req(1, idx);
+ }
+ virtual int Opcode() const;
+ virtual const Type* Value(PhaseGVN* phase) const;
+ virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
+ virtual const Type *bottom_type() const;
+ virtual bool pinned() const { return true; }
+ virtual int required_outcnt() const { return _size; }
+};
+
+//------------------------------JumpNode---------------------------------------
+// Indirect branch. Uses PCTable above to implement a switch statement.
+// It emits as a table load and local branch.
+class JumpNode : public PCTableNode {
+public:
+ JumpNode( Node* control, Node* switch_val, uint size) : PCTableNode(control, switch_val, size) {
+ init_class_id(Class_Jump);
+ }
+ virtual int Opcode() const;
+ virtual const RegMask& out_RegMask() const;
+ virtual const Node* is_block_proj() const { return this; }
+#ifndef PRODUCT
+ virtual void related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const;
+#endif
+};
+
+class JumpProjNode : public JProjNode {
+ virtual uint hash() const;
+ virtual uint cmp( const Node &n ) const;
+ virtual uint size_of() const { return sizeof(*this); }
+
+ private:
+ const int _dest_bci;
+ const uint _proj_no;
+ const int _switch_val;
+ public:
+ JumpProjNode(Node* jumpnode, uint proj_no, int dest_bci, int switch_val)
+ : JProjNode(jumpnode, proj_no), _dest_bci(dest_bci), _proj_no(proj_no), _switch_val(switch_val) {
+ init_class_id(Class_JumpProj);
+ }
+
+ virtual int Opcode() const;
+ virtual const Type* bottom_type() const { return Type::CONTROL; }
+ int dest_bci() const { return _dest_bci; }
+ int switch_val() const { return _switch_val; }
+ uint proj_no() const { return _proj_no; }
+#ifndef PRODUCT
+ virtual void dump_spec(outputStream *st) const;
+ virtual void dump_compact_spec(outputStream *st) const;
+ virtual void related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const;
+#endif
+};
+
+//------------------------------CatchNode--------------------------------------
+// Helper node to fork exceptions. "Catch" catches any exceptions thrown by
+// a just-prior call. Looks like a PCTableNode but emits no code - just the
+// table. The table lookup and branch is implemented by RethrowNode.
+class CatchNode : public PCTableNode {
+public:
+ CatchNode( Node *ctrl, Node *idx, uint size ) : PCTableNode(ctrl,idx,size){
+ init_class_id(Class_Catch);
+ }
+ virtual int Opcode() const;
+ virtual const Type* Value(PhaseGVN* phase) const;
+};
+
+// CatchProjNode controls which exception handler is targetted after a call.
+// It is passed in the bci of the target handler, or no_handler_bci in case
+// the projection doesn't lead to an exception handler.
+class CatchProjNode : public CProjNode {
+ virtual uint hash() const;
+ virtual uint cmp( const Node &n ) const;
+ virtual uint size_of() const { return sizeof(*this); }
+
+private:
+ const int _handler_bci;
+
+public:
+ enum {
+ fall_through_index = 0, // the fall through projection index
+ catch_all_index = 1, // the projection index for catch-alls
+ no_handler_bci = -1 // the bci for fall through or catch-all projs
+ };
+
+ CatchProjNode(Node* catchnode, uint proj_no, int handler_bci)
+ : CProjNode(catchnode, proj_no), _handler_bci(handler_bci) {
+ init_class_id(Class_CatchProj);
+ assert(proj_no != fall_through_index || handler_bci < 0, "fall through case must have bci < 0");
+ }
+
+ virtual int Opcode() const;
+ virtual Node* Identity(PhaseGVN* phase);
+ virtual const Type *bottom_type() const { return Type::CONTROL; }
+ int handler_bci() const { return _handler_bci; }
+ bool is_handler_proj() const { return _handler_bci >= 0; }
+#ifndef PRODUCT
+ virtual void dump_spec(outputStream *st) const;
+#endif
+};
+
+
+//---------------------------------CreateExNode--------------------------------
+// Helper node to create the exception coming back from a call
+class CreateExNode : public TypeNode {
+public:
+ CreateExNode(const Type* t, Node* control, Node* i_o) : TypeNode(t, 2) {
+ init_req(0, control);
+ init_req(1, i_o);
+ }
+ virtual int Opcode() const;
+ virtual Node* Identity(PhaseGVN* phase);
+ virtual bool pinned() const { return true; }
+ uint match_edge(uint idx) const { return 0; }
+ virtual uint ideal_reg() const { return Op_RegP; }
+};
+
+//------------------------------NeverBranchNode-------------------------------
+// The never-taken branch. Used to give the appearance of exiting infinite
+// loops to those algorithms that like all paths to be reachable. Encodes
+// empty.
+class NeverBranchNode : public MultiBranchNode {
+public:
+ NeverBranchNode( Node *ctrl ) : MultiBranchNode(1) { init_req(0,ctrl); }
+ virtual int Opcode() const;
+ virtual bool pinned() const { return true; };
+ virtual const Type *bottom_type() const { return TypeTuple::IFBOTH; }
+ virtual const Type* Value(PhaseGVN* phase) const;
+ virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
+ virtual int required_outcnt() const { return 2; }
+ virtual void emit(CodeBuffer &cbuf, PhaseRegAlloc *ra_) const { }
+ virtual uint size(PhaseRegAlloc *ra_) const { return 0; }
+#ifndef PRODUCT
+ virtual void format( PhaseRegAlloc *, outputStream *st ) const;
+#endif
+};
+
+#endif // SHARE_VM_OPTO_CFGNODE_HPP