--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/ci/ciTypeFlow.hpp Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,959 @@
+/*
+ * Copyright (c) 2000, 2012, 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_CI_CITYPEFLOW_HPP
+#define SHARE_VM_CI_CITYPEFLOW_HPP
+
+#ifdef COMPILER2
+#include "ci/ciEnv.hpp"
+#include "ci/ciKlass.hpp"
+#include "ci/ciMethodBlocks.hpp"
+#endif
+#ifdef SHARK
+#include "ci/ciEnv.hpp"
+#include "ci/ciKlass.hpp"
+#include "ci/ciMethodBlocks.hpp"
+#include "shark/shark_globals.hpp"
+#endif
+
+
+class ciTypeFlow : public ResourceObj {
+private:
+ ciEnv* _env;
+ ciMethod* _method;
+ ciMethodBlocks* _methodBlocks;
+ int _osr_bci;
+
+ // information cached from the method:
+ int _max_locals;
+ int _max_stack;
+ int _code_size;
+ bool _has_irreducible_entry;
+
+ const char* _failure_reason;
+
+public:
+ class StateVector;
+ class Loop;
+ class Block;
+
+ // Build a type flow analyzer
+ // Do an OSR analysis if osr_bci >= 0.
+ ciTypeFlow(ciEnv* env, ciMethod* method, int osr_bci = InvocationEntryBci);
+
+ // Accessors
+ ciMethod* method() const { return _method; }
+ ciEnv* env() { return _env; }
+ Arena* arena() { return _env->arena(); }
+ bool is_osr_flow() const{ return _osr_bci != InvocationEntryBci; }
+ int start_bci() const { return is_osr_flow()? _osr_bci: 0; }
+ int max_locals() const { return _max_locals; }
+ int max_stack() const { return _max_stack; }
+ int max_cells() const { return _max_locals + _max_stack; }
+ int code_size() const { return _code_size; }
+ bool has_irreducible_entry() const { return _has_irreducible_entry; }
+
+ // Represents information about an "active" jsr call. This
+ // class represents a call to the routine at some entry address
+ // with some distinct return address.
+ class JsrRecord : public ResourceObj {
+ private:
+ int _entry_address;
+ int _return_address;
+ public:
+ JsrRecord(int entry_address, int return_address) {
+ _entry_address = entry_address;
+ _return_address = return_address;
+ }
+
+ int entry_address() const { return _entry_address; }
+ int return_address() const { return _return_address; }
+
+ void print_on(outputStream* st) const {
+#ifndef PRODUCT
+ st->print("%d->%d", entry_address(), return_address());
+#endif
+ }
+ };
+
+ // A JsrSet represents some set of JsrRecords. This class
+ // is used to record a set of all jsr routines which we permit
+ // execution to return (ret) from.
+ //
+ // During abstract interpretation, JsrSets are used to determine
+ // whether two paths which reach a given block are unique, and
+ // should be cloned apart, or are compatible, and should merge
+ // together.
+ //
+ // Note that different amounts of effort can be expended determining
+ // if paths are compatible. <DISCUSSION>
+ class JsrSet : public ResourceObj {
+ private:
+ GrowableArray<JsrRecord*>* _set;
+
+ JsrRecord* record_at(int i) {
+ return _set->at(i);
+ }
+
+ // Insert the given JsrRecord into the JsrSet, maintaining the order
+ // of the set and replacing any element with the same entry address.
+ void insert_jsr_record(JsrRecord* record);
+
+ // Remove the JsrRecord with the given return address from the JsrSet.
+ void remove_jsr_record(int return_address);
+
+ public:
+ JsrSet(Arena* arena, int default_len = 4);
+
+ // Copy this JsrSet.
+ void copy_into(JsrSet* jsrs);
+
+ // Is this JsrSet compatible with some other JsrSet?
+ bool is_compatible_with(JsrSet* other);
+
+ // Apply the effect of a single bytecode to the JsrSet.
+ void apply_control(ciTypeFlow* analyzer,
+ ciBytecodeStream* str,
+ StateVector* state);
+
+ // What is the cardinality of this set?
+ int size() const { return _set->length(); }
+
+ void print_on(outputStream* st) const PRODUCT_RETURN;
+ };
+
+ class LocalSet VALUE_OBJ_CLASS_SPEC {
+ private:
+ enum Constants { max = 63 };
+ uint64_t _bits;
+ public:
+ LocalSet() : _bits(0) {}
+ void add(uint32_t i) { if (i < (uint32_t)max) _bits |= (1LL << i); }
+ void add(LocalSet* ls) { _bits |= ls->_bits; }
+ bool test(uint32_t i) const { return i < (uint32_t)max ? (_bits>>i)&1U : true; }
+ void clear() { _bits = 0; }
+ void print_on(outputStream* st, int limit) const PRODUCT_RETURN;
+ };
+
+ // Used as a combined index for locals and temps
+ enum Cell {
+ Cell_0, Cell_max = INT_MAX
+ };
+
+ // A StateVector summarizes the type information at some
+ // point in the program
+ class StateVector : public ResourceObj {
+ private:
+ ciType** _types;
+ int _stack_size;
+ int _monitor_count;
+ ciTypeFlow* _outer;
+
+ int _trap_bci;
+ int _trap_index;
+
+ LocalSet _def_locals; // For entire block
+
+ static ciType* type_meet_internal(ciType* t1, ciType* t2, ciTypeFlow* analyzer);
+
+ public:
+ // Special elements in our type lattice.
+ enum {
+ T_TOP = T_VOID, // why not?
+ T_BOTTOM = T_CONFLICT,
+ T_LONG2 = T_SHORT, // 2nd word of T_LONG
+ T_DOUBLE2 = T_CHAR, // 2nd word of T_DOUBLE
+ T_NULL = T_BYTE // for now.
+ };
+ static ciType* top_type() { return ciType::make((BasicType)T_TOP); }
+ static ciType* bottom_type() { return ciType::make((BasicType)T_BOTTOM); }
+ static ciType* long2_type() { return ciType::make((BasicType)T_LONG2); }
+ static ciType* double2_type(){ return ciType::make((BasicType)T_DOUBLE2); }
+ static ciType* null_type() { return ciType::make((BasicType)T_NULL); }
+
+ static ciType* half_type(ciType* t) {
+ switch (t->basic_type()) {
+ case T_LONG: return long2_type();
+ case T_DOUBLE: return double2_type();
+ default: ShouldNotReachHere(); return NULL;
+ }
+ }
+
+ // The meet operation for our type lattice.
+ ciType* type_meet(ciType* t1, ciType* t2) {
+ return type_meet_internal(t1, t2, outer());
+ }
+
+ // Accessors
+ ciTypeFlow* outer() const { return _outer; }
+
+ int stack_size() const { return _stack_size; }
+ void set_stack_size(int ss) { _stack_size = ss; }
+
+ int monitor_count() const { return _monitor_count; }
+ void set_monitor_count(int mc) { _monitor_count = mc; }
+
+ LocalSet* def_locals() { return &_def_locals; }
+ const LocalSet* def_locals() const { return &_def_locals; }
+
+ static Cell start_cell() { return (Cell)0; }
+ static Cell next_cell(Cell c) { return (Cell)(((int)c) + 1); }
+ Cell limit_cell() const {
+ return (Cell)(outer()->max_locals() + stack_size());
+ }
+
+ // Cell creation
+ Cell local(int lnum) const {
+ assert(lnum < outer()->max_locals(), "index check");
+ return (Cell)(lnum);
+ }
+
+ Cell stack(int snum) const {
+ assert(snum < stack_size(), "index check");
+ return (Cell)(outer()->max_locals() + snum);
+ }
+
+ Cell tos() const { return stack(stack_size()-1); }
+
+ // For external use only:
+ ciType* local_type_at(int i) const { return type_at(local(i)); }
+ ciType* stack_type_at(int i) const { return type_at(stack(i)); }
+
+ // Accessors for the type of some Cell c
+ ciType* type_at(Cell c) const {
+ assert(start_cell() <= c && c < limit_cell(), "out of bounds");
+ return _types[c];
+ }
+
+ void set_type_at(Cell c, ciType* type) {
+ assert(start_cell() <= c && c < limit_cell(), "out of bounds");
+ _types[c] = type;
+ }
+
+ // Top-of-stack operations.
+ void set_type_at_tos(ciType* type) { set_type_at(tos(), type); }
+ ciType* type_at_tos() const { return type_at(tos()); }
+
+ void push(ciType* type) {
+ _stack_size++;
+ set_type_at_tos(type);
+ }
+ void pop() {
+ debug_only(set_type_at_tos(bottom_type()));
+ _stack_size--;
+ }
+ ciType* pop_value() {
+ ciType* t = type_at_tos();
+ pop();
+ return t;
+ }
+
+ // Convenience operations.
+ bool is_reference(ciType* type) const {
+ return type == null_type() || !type->is_primitive_type();
+ }
+ bool is_int(ciType* type) const {
+ return type->basic_type() == T_INT;
+ }
+ bool is_long(ciType* type) const {
+ return type->basic_type() == T_LONG;
+ }
+ bool is_float(ciType* type) const {
+ return type->basic_type() == T_FLOAT;
+ }
+ bool is_double(ciType* type) const {
+ return type->basic_type() == T_DOUBLE;
+ }
+
+ void store_to_local(int lnum) {
+ _def_locals.add((uint) lnum);
+ }
+
+ void push_translate(ciType* type);
+
+ void push_int() {
+ push(ciType::make(T_INT));
+ }
+ void pop_int() {
+ assert(is_int(type_at_tos()), "must be integer");
+ pop();
+ }
+ void check_int(Cell c) {
+ assert(is_int(type_at(c)), "must be integer");
+ }
+ void push_double() {
+ push(ciType::make(T_DOUBLE));
+ push(double2_type());
+ }
+ void pop_double() {
+ assert(type_at_tos() == double2_type(), "must be 2nd half");
+ pop();
+ assert(is_double(type_at_tos()), "must be double");
+ pop();
+ }
+ void push_float() {
+ push(ciType::make(T_FLOAT));
+ }
+ void pop_float() {
+ assert(is_float(type_at_tos()), "must be float");
+ pop();
+ }
+ void push_long() {
+ push(ciType::make(T_LONG));
+ push(long2_type());
+ }
+ void pop_long() {
+ assert(type_at_tos() == long2_type(), "must be 2nd half");
+ pop();
+ assert(is_long(type_at_tos()), "must be long");
+ pop();
+ }
+ void push_object(ciKlass* klass) {
+ push(klass);
+ }
+ void pop_object() {
+ assert(is_reference(type_at_tos()), "must be reference type");
+ pop();
+ }
+ void pop_array() {
+ assert(type_at_tos() == null_type() ||
+ type_at_tos()->is_array_klass(), "must be array type");
+ pop();
+ }
+ // pop_objArray and pop_typeArray narrow the tos to ciObjArrayKlass
+ // or ciTypeArrayKlass (resp.). In the rare case that an explicit
+ // null is popped from the stack, we return NULL. Caller beware.
+ ciObjArrayKlass* pop_objArray() {
+ ciType* array = pop_value();
+ if (array == null_type()) return NULL;
+ assert(array->is_obj_array_klass(), "must be object array type");
+ return array->as_obj_array_klass();
+ }
+ ciTypeArrayKlass* pop_typeArray() {
+ ciType* array = pop_value();
+ if (array == null_type()) return NULL;
+ assert(array->is_type_array_klass(), "must be prim array type");
+ return array->as_type_array_klass();
+ }
+ void push_null() {
+ push(null_type());
+ }
+ void do_null_assert(ciKlass* unloaded_klass);
+
+ // Helper convenience routines.
+ void do_aaload(ciBytecodeStream* str);
+ void do_checkcast(ciBytecodeStream* str);
+ void do_getfield(ciBytecodeStream* str);
+ void do_getstatic(ciBytecodeStream* str);
+ void do_invoke(ciBytecodeStream* str, bool has_receiver);
+ void do_jsr(ciBytecodeStream* str);
+ void do_ldc(ciBytecodeStream* str);
+ void do_multianewarray(ciBytecodeStream* str);
+ void do_new(ciBytecodeStream* str);
+ void do_newarray(ciBytecodeStream* str);
+ void do_putfield(ciBytecodeStream* str);
+ void do_putstatic(ciBytecodeStream* str);
+ void do_ret(ciBytecodeStream* str);
+
+ void overwrite_local_double_long(int index) {
+ // Invalidate the previous local if it contains first half of
+ // a double or long value since it's seconf half is being overwritten.
+ int prev_index = index - 1;
+ if (prev_index >= 0 &&
+ (is_double(type_at(local(prev_index))) ||
+ is_long(type_at(local(prev_index))))) {
+ set_type_at(local(prev_index), bottom_type());
+ }
+ }
+
+ void load_local_object(int index) {
+ ciType* type = type_at(local(index));
+ assert(is_reference(type), "must be reference type");
+ push(type);
+ }
+ void store_local_object(int index) {
+ ciType* type = pop_value();
+ assert(is_reference(type) || type->is_return_address(),
+ "must be reference type or return address");
+ overwrite_local_double_long(index);
+ set_type_at(local(index), type);
+ store_to_local(index);
+ }
+
+ void load_local_double(int index) {
+ ciType* type = type_at(local(index));
+ ciType* type2 = type_at(local(index+1));
+ assert(is_double(type), "must be double type");
+ assert(type2 == double2_type(), "must be 2nd half");
+ push(type);
+ push(double2_type());
+ }
+ void store_local_double(int index) {
+ ciType* type2 = pop_value();
+ ciType* type = pop_value();
+ assert(is_double(type), "must be double");
+ assert(type2 == double2_type(), "must be 2nd half");
+ overwrite_local_double_long(index);
+ set_type_at(local(index), type);
+ set_type_at(local(index+1), type2);
+ store_to_local(index);
+ store_to_local(index+1);
+ }
+
+ void load_local_float(int index) {
+ ciType* type = type_at(local(index));
+ assert(is_float(type), "must be float type");
+ push(type);
+ }
+ void store_local_float(int index) {
+ ciType* type = pop_value();
+ assert(is_float(type), "must be float type");
+ overwrite_local_double_long(index);
+ set_type_at(local(index), type);
+ store_to_local(index);
+ }
+
+ void load_local_int(int index) {
+ ciType* type = type_at(local(index));
+ assert(is_int(type), "must be int type");
+ push(type);
+ }
+ void store_local_int(int index) {
+ ciType* type = pop_value();
+ assert(is_int(type), "must be int type");
+ overwrite_local_double_long(index);
+ set_type_at(local(index), type);
+ store_to_local(index);
+ }
+
+ void load_local_long(int index) {
+ ciType* type = type_at(local(index));
+ ciType* type2 = type_at(local(index+1));
+ assert(is_long(type), "must be long type");
+ assert(type2 == long2_type(), "must be 2nd half");
+ push(type);
+ push(long2_type());
+ }
+ void store_local_long(int index) {
+ ciType* type2 = pop_value();
+ ciType* type = pop_value();
+ assert(is_long(type), "must be long");
+ assert(type2 == long2_type(), "must be 2nd half");
+ overwrite_local_double_long(index);
+ set_type_at(local(index), type);
+ set_type_at(local(index+1), type2);
+ store_to_local(index);
+ store_to_local(index+1);
+ }
+
+ // Stop interpretation of this path with a trap.
+ void trap(ciBytecodeStream* str, ciKlass* klass, int index);
+
+ public:
+ StateVector(ciTypeFlow* outer);
+
+ // Copy our value into some other StateVector
+ void copy_into(StateVector* copy) const;
+
+ // Meets this StateVector with another, destructively modifying this
+ // one. Returns true if any modification takes place.
+ bool meet(const StateVector* incoming);
+
+ // Ditto, except that the incoming state is coming from an exception.
+ bool meet_exception(ciInstanceKlass* exc, const StateVector* incoming);
+
+ // Apply the effect of one bytecode to this StateVector
+ bool apply_one_bytecode(ciBytecodeStream* stream);
+
+ // What is the bci of the trap?
+ int trap_bci() { return _trap_bci; }
+
+ // What is the index associated with the trap?
+ int trap_index() { return _trap_index; }
+
+ void print_cell_on(outputStream* st, Cell c) const PRODUCT_RETURN;
+ void print_on(outputStream* st) const PRODUCT_RETURN;
+ };
+
+ // Parameter for "find_block" calls:
+ // Describes the difference between a public and backedge copy.
+ enum CreateOption {
+ create_public_copy,
+ create_backedge_copy,
+ no_create
+ };
+
+ // Successor iterator
+ class SuccIter : public StackObj {
+ private:
+ Block* _pred;
+ int _index;
+ Block* _succ;
+ public:
+ SuccIter() : _pred(NULL), _index(-1), _succ(NULL) {}
+ SuccIter(Block* pred) : _pred(pred), _index(-1), _succ(NULL) { next(); }
+ int index() { return _index; }
+ Block* pred() { return _pred; } // Return predecessor
+ bool done() { return _index < 0; } // Finished?
+ Block* succ() { return _succ; } // Return current successor
+ void next(); // Advance
+ void set_succ(Block* succ); // Update current successor
+ bool is_normal_ctrl() { return index() < _pred->successors()->length(); }
+ };
+
+ // A basic block
+ class Block : public ResourceObj {
+ private:
+ ciBlock* _ciblock;
+ GrowableArray<Block*>* _exceptions;
+ GrowableArray<ciInstanceKlass*>* _exc_klasses;
+ GrowableArray<Block*>* _successors;
+ GrowableArray<Block*>* _predecessors;
+ StateVector* _state;
+ JsrSet* _jsrs;
+
+ int _trap_bci;
+ int _trap_index;
+
+ // pre_order, assigned at first visit. Used as block ID and "visited" tag
+ int _pre_order;
+
+ // A post-order, used to compute the reverse post order (RPO) provided to the client
+ int _post_order; // used to compute rpo
+
+ // Has this block been cloned for a loop backedge?
+ bool _backedge_copy;
+
+ // This block is entry to irreducible loop.
+ bool _irreducible_entry;
+
+ // This block has monitor entry point.
+ bool _has_monitorenter;
+
+ // A pointer used for our internal work list
+ bool _on_work_list; // on the work list
+ Block* _next;
+ Block* _rpo_next; // Reverse post order list
+
+ // Loop info
+ Loop* _loop; // nearest loop
+
+ ciBlock* ciblock() const { return _ciblock; }
+ StateVector* state() const { return _state; }
+
+ // Compute the exceptional successors and types for this Block.
+ void compute_exceptions();
+
+ public:
+ // constructors
+ Block(ciTypeFlow* outer, ciBlock* ciblk, JsrSet* jsrs);
+
+ void set_trap(int trap_bci, int trap_index) {
+ _trap_bci = trap_bci;
+ _trap_index = trap_index;
+ assert(has_trap(), "");
+ }
+ bool has_trap() const { return _trap_bci != -1; }
+ int trap_bci() const { assert(has_trap(), ""); return _trap_bci; }
+ int trap_index() const { assert(has_trap(), ""); return _trap_index; }
+
+ // accessors
+ ciTypeFlow* outer() const { return state()->outer(); }
+ int start() const { return _ciblock->start_bci(); }
+ int limit() const { return _ciblock->limit_bci(); }
+ int control() const { return _ciblock->control_bci(); }
+ JsrSet* jsrs() const { return _jsrs; }
+
+ bool is_backedge_copy() const { return _backedge_copy; }
+ void set_backedge_copy(bool z);
+ int backedge_copy_count() const { return outer()->backedge_copy_count(ciblock()->index(), _jsrs); }
+
+ // access to entry state
+ int stack_size() const { return _state->stack_size(); }
+ int monitor_count() const { return _state->monitor_count(); }
+ ciType* local_type_at(int i) const { return _state->local_type_at(i); }
+ ciType* stack_type_at(int i) const { return _state->stack_type_at(i); }
+
+ // Data flow on locals
+ bool is_invariant_local(uint v) const {
+ assert(is_loop_head(), "only loop heads");
+ // Find outermost loop with same loop head
+ Loop* lp = loop();
+ while (lp->parent() != NULL) {
+ if (lp->parent()->head() != lp->head()) break;
+ lp = lp->parent();
+ }
+ return !lp->def_locals()->test(v);
+ }
+ LocalSet* def_locals() { return _state->def_locals(); }
+ const LocalSet* def_locals() const { return _state->def_locals(); }
+
+ // Get the successors for this Block.
+ GrowableArray<Block*>* successors(ciBytecodeStream* str,
+ StateVector* state,
+ JsrSet* jsrs);
+ GrowableArray<Block*>* successors() {
+ assert(_successors != NULL, "must be filled in");
+ return _successors;
+ }
+
+ // Predecessors of this block (including exception edges)
+ GrowableArray<Block*>* predecessors() {
+ assert(_predecessors != NULL, "must be filled in");
+ return _predecessors;
+ }
+
+ // Get the exceptional successors for this Block.
+ GrowableArray<Block*>* exceptions() {
+ if (_exceptions == NULL) {
+ compute_exceptions();
+ }
+ return _exceptions;
+ }
+
+ // Get the exception klasses corresponding to the
+ // exceptional successors for this Block.
+ GrowableArray<ciInstanceKlass*>* exc_klasses() {
+ if (_exc_klasses == NULL) {
+ compute_exceptions();
+ }
+ return _exc_klasses;
+ }
+
+ // Is this Block compatible with a given JsrSet?
+ bool is_compatible_with(JsrSet* other) {
+ return _jsrs->is_compatible_with(other);
+ }
+
+ // Copy the value of our state vector into another.
+ void copy_state_into(StateVector* copy) const {
+ _state->copy_into(copy);
+ }
+
+ // Copy the value of our JsrSet into another
+ void copy_jsrs_into(JsrSet* copy) const {
+ _jsrs->copy_into(copy);
+ }
+
+ // Meets the start state of this block with another state, destructively
+ // modifying this one. Returns true if any modification takes place.
+ bool meet(const StateVector* incoming) {
+ return state()->meet(incoming);
+ }
+
+ // Ditto, except that the incoming state is coming from an
+ // exception path. This means the stack is replaced by the
+ // appropriate exception type.
+ bool meet_exception(ciInstanceKlass* exc, const StateVector* incoming) {
+ return state()->meet_exception(exc, incoming);
+ }
+
+ // Work list manipulation
+ void set_next(Block* block) { _next = block; }
+ Block* next() const { return _next; }
+
+ void set_on_work_list(bool c) { _on_work_list = c; }
+ bool is_on_work_list() const { return _on_work_list; }
+
+ bool has_pre_order() const { return _pre_order >= 0; }
+ void set_pre_order(int po) { assert(!has_pre_order(), ""); _pre_order = po; }
+ int pre_order() const { assert(has_pre_order(), ""); return _pre_order; }
+ void set_next_pre_order() { set_pre_order(outer()->inc_next_pre_order()); }
+ bool is_start() const { return _pre_order == outer()->start_block_num(); }
+
+ // Reverse post order
+ void df_init();
+ bool has_post_order() const { return _post_order >= 0; }
+ void set_post_order(int po) { assert(!has_post_order() && po >= 0, ""); _post_order = po; }
+ void reset_post_order(int o){ _post_order = o; }
+ int post_order() const { assert(has_post_order(), ""); return _post_order; }
+
+ bool has_rpo() const { return has_post_order() && outer()->have_block_count(); }
+ int rpo() const { assert(has_rpo(), ""); return outer()->block_count() - post_order() - 1; }
+ void set_rpo_next(Block* b) { _rpo_next = b; }
+ Block* rpo_next() { return _rpo_next; }
+
+ // Loops
+ Loop* loop() const { return _loop; }
+ void set_loop(Loop* lp) { _loop = lp; }
+ bool is_loop_head() const { return _loop && _loop->head() == this; }
+ void set_irreducible_entry(bool c) { _irreducible_entry = c; }
+ bool is_irreducible_entry() const { return _irreducible_entry; }
+ void set_has_monitorenter() { _has_monitorenter = true; }
+ bool has_monitorenter() const { return _has_monitorenter; }
+ bool is_visited() const { return has_pre_order(); }
+ bool is_post_visited() const { return has_post_order(); }
+ bool is_clonable_exit(Loop* lp);
+ Block* looping_succ(Loop* lp); // Successor inside of loop
+ bool is_single_entry_loop_head() const {
+ if (!is_loop_head()) return false;
+ for (Loop* lp = loop(); lp != NULL && lp->head() == this; lp = lp->parent())
+ if (lp->is_irreducible()) return false;
+ return true;
+ }
+
+ void print_value_on(outputStream* st) const PRODUCT_RETURN;
+ void print_on(outputStream* st) const PRODUCT_RETURN;
+ };
+
+ // Loop
+ class Loop : public ResourceObj {
+ private:
+ Loop* _parent;
+ Loop* _sibling; // List of siblings, null terminated
+ Loop* _child; // Head of child list threaded thru sibling pointer
+ Block* _head; // Head of loop
+ Block* _tail; // Tail of loop
+ bool _irreducible;
+ LocalSet _def_locals;
+
+ public:
+ Loop(Block* head, Block* tail) :
+ _head(head), _tail(tail),
+ _parent(NULL), _sibling(NULL), _child(NULL),
+ _irreducible(false), _def_locals() {}
+
+ Loop* parent() const { return _parent; }
+ Loop* sibling() const { return _sibling; }
+ Loop* child() const { return _child; }
+ Block* head() const { return _head; }
+ Block* tail() const { return _tail; }
+ void set_parent(Loop* p) { _parent = p; }
+ void set_sibling(Loop* s) { _sibling = s; }
+ void set_child(Loop* c) { _child = c; }
+ void set_head(Block* hd) { _head = hd; }
+ void set_tail(Block* tl) { _tail = tl; }
+
+ int depth() const; // nesting depth
+
+ // Returns true if lp is a nested loop or us.
+ bool contains(Loop* lp) const;
+ bool contains(Block* blk) const { return contains(blk->loop()); }
+
+ // Data flow on locals
+ LocalSet* def_locals() { return &_def_locals; }
+ const LocalSet* def_locals() const { return &_def_locals; }
+
+ // Merge the branch lp into this branch, sorting on the loop head
+ // pre_orders. Returns the new branch.
+ Loop* sorted_merge(Loop* lp);
+
+ // Mark non-single entry to loop
+ void set_irreducible(Block* entry) {
+ _irreducible = true;
+ entry->set_irreducible_entry(true);
+ }
+ bool is_irreducible() const { return _irreducible; }
+
+ bool is_root() const { return _tail->pre_order() == max_jint; }
+
+ void print(outputStream* st = tty, int indent = 0) const PRODUCT_RETURN;
+ };
+
+ // Postorder iteration over the loop tree.
+ class PostorderLoops : public StackObj {
+ private:
+ Loop* _root;
+ Loop* _current;
+ public:
+ PostorderLoops(Loop* root) : _root(root), _current(root) {
+ while (_current->child() != NULL) {
+ _current = _current->child();
+ }
+ }
+ bool done() { return _current == NULL; } // Finished iterating?
+ void next(); // Advance to next loop
+ Loop* current() { return _current; } // Return current loop.
+ };
+
+ // Preorder iteration over the loop tree.
+ class PreorderLoops : public StackObj {
+ private:
+ Loop* _root;
+ Loop* _current;
+ public:
+ PreorderLoops(Loop* root) : _root(root), _current(root) {}
+ bool done() { return _current == NULL; } // Finished iterating?
+ void next(); // Advance to next loop
+ Loop* current() { return _current; } // Return current loop.
+ };
+
+ // Standard indexes of successors, for various bytecodes.
+ enum {
+ FALL_THROUGH = 0, // normal control
+ IF_NOT_TAKEN = 0, // the not-taken branch of an if (i.e., fall-through)
+ IF_TAKEN = 1, // the taken branch of an if
+ GOTO_TARGET = 0, // unique successor for goto, jsr, or ret
+ SWITCH_DEFAULT = 0, // default branch of a switch
+ SWITCH_CASES = 1 // first index for any non-default switch branches
+ // Unlike in other blocks, the successors of a switch are listed uniquely.
+ };
+
+private:
+ // A mapping from pre_order to Blocks. This array is created
+ // only at the end of the flow.
+ Block** _block_map;
+
+ // For each ciBlock index, a list of Blocks which share this ciBlock.
+ GrowableArray<Block*>** _idx_to_blocklist;
+ // count of ciBlocks
+ int _ciblock_count;
+
+ // Tells if a given instruction is able to generate an exception edge.
+ bool can_trap(ciBytecodeStream& str);
+
+ // Clone the loop heads. Returns true if any cloning occurred.
+ bool clone_loop_heads(Loop* lp, StateVector* temp_vector, JsrSet* temp_set);
+
+ // Clone lp's head and replace tail's successors with clone.
+ Block* clone_loop_head(Loop* lp, StateVector* temp_vector, JsrSet* temp_set);
+
+public:
+ // Return the block beginning at bci which has a JsrSet compatible
+ // with jsrs.
+ Block* block_at(int bci, JsrSet* set, CreateOption option = create_public_copy);
+
+ // block factory
+ Block* get_block_for(int ciBlockIndex, JsrSet* jsrs, CreateOption option = create_public_copy);
+
+ // How many of the blocks have the backedge_copy bit set?
+ int backedge_copy_count(int ciBlockIndex, JsrSet* jsrs) const;
+
+ // Return an existing block containing bci which has a JsrSet compatible
+ // with jsrs, or NULL if there is none.
+ Block* existing_block_at(int bci, JsrSet* set) { return block_at(bci, set, no_create); }
+
+ // Tell whether the flow analysis has encountered an error of some sort.
+ bool failing() { return env()->failing() || _failure_reason != NULL; }
+
+ // Reason this compilation is failing, such as "too many basic blocks".
+ const char* failure_reason() { return _failure_reason; }
+
+ // Note a failure.
+ void record_failure(const char* reason);
+
+ // Return the block of a given pre-order number.
+ int have_block_count() const { return _block_map != NULL; }
+ int block_count() const { assert(have_block_count(), "");
+ return _next_pre_order; }
+ Block* pre_order_at(int po) const { assert(0 <= po && po < block_count(), "out of bounds");
+ return _block_map[po]; }
+ Block* start_block() const { return pre_order_at(start_block_num()); }
+ int start_block_num() const { return 0; }
+ Block* rpo_at(int rpo) const { assert(0 <= rpo && rpo < block_count(), "out of bounds");
+ return _block_map[rpo]; }
+ int next_pre_order() { return _next_pre_order; }
+ int inc_next_pre_order() { return _next_pre_order++; }
+
+private:
+ // A work list used during flow analysis.
+ Block* _work_list;
+
+ // List of blocks in reverse post order
+ Block* _rpo_list;
+
+ // Next Block::_pre_order. After mapping, doubles as block_count.
+ int _next_pre_order;
+
+ // Are there more blocks on the work list?
+ bool work_list_empty() { return _work_list == NULL; }
+
+ // Get the next basic block from our work list.
+ Block* work_list_next();
+
+ // Add a basic block to our work list.
+ void add_to_work_list(Block* block);
+
+ // Prepend a basic block to rpo list.
+ void prepend_to_rpo_list(Block* blk) {
+ blk->set_rpo_next(_rpo_list);
+ _rpo_list = blk;
+ }
+
+ // Root of the loop tree
+ Loop* _loop_tree_root;
+
+ // State used for make_jsr_record
+ int _jsr_count;
+ GrowableArray<JsrRecord*>* _jsr_records;
+
+public:
+ // Make a JsrRecord for a given (entry, return) pair, if such a record
+ // does not already exist.
+ JsrRecord* make_jsr_record(int entry_address, int return_address);
+
+ void set_loop_tree_root(Loop* ltr) { _loop_tree_root = ltr; }
+ Loop* loop_tree_root() { return _loop_tree_root; }
+
+private:
+ // Get the initial state for start_bci:
+ const StateVector* get_start_state();
+
+ // Merge the current state into all exceptional successors at the
+ // current point in the code.
+ void flow_exceptions(GrowableArray<Block*>* exceptions,
+ GrowableArray<ciInstanceKlass*>* exc_klasses,
+ StateVector* state);
+
+ // Merge the current state into all successors at the current point
+ // in the code.
+ void flow_successors(GrowableArray<Block*>* successors,
+ StateVector* state);
+
+ // Interpret the effects of the bytecodes on the incoming state
+ // vector of a basic block. Push the changed state to succeeding
+ // basic blocks.
+ void flow_block(Block* block,
+ StateVector* scratch_state,
+ JsrSet* scratch_jsrs);
+
+ // Perform the type flow analysis, creating and cloning Blocks as
+ // necessary.
+ void flow_types();
+
+ // Perform the depth first type flow analysis. Helper for flow_types.
+ void df_flow_types(Block* start,
+ bool do_flow,
+ StateVector* temp_vector,
+ JsrSet* temp_set);
+
+ // Incrementally build loop tree.
+ void build_loop_tree(Block* blk);
+
+ // Create the block map, which indexes blocks in pre_order.
+ void map_blocks();
+
+public:
+ // Perform type inference flow analysis.
+ void do_flow();
+
+ // Determine if bci is dominated by dom_bci
+ bool is_dominated_by(int bci, int dom_bci);
+
+ void print_on(outputStream* st) const PRODUCT_RETURN;
+
+ void rpo_print_on(outputStream* st) const PRODUCT_RETURN;
+};
+
+#endif // SHARE_VM_CI_CITYPEFLOW_HPP