--- a/hotspot/src/share/vm/ci/ciTypeFlow.hpp Wed Sep 17 08:29:17 2008 -0700
+++ b/hotspot/src/share/vm/ci/ciTypeFlow.hpp Wed Sep 17 12:59:52 2008 -0700
@@ -34,11 +34,13 @@
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
@@ -55,6 +57,7 @@
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
@@ -125,6 +128,19 @@
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
@@ -142,6 +158,8 @@
int _trap_bci;
int _trap_index;
+ LocalSet _def_locals; // For entire block
+
static ciType* type_meet_internal(ciType* t1, ciType* t2, ciTypeFlow* analyzer);
public:
@@ -181,6 +199,9 @@
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 {
@@ -250,6 +271,10 @@
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() {
@@ -358,6 +383,7 @@
"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) {
@@ -376,6 +402,8 @@
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) {
@@ -388,6 +416,7 @@
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) {
@@ -400,6 +429,7 @@
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) {
@@ -418,6 +448,8 @@
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.
@@ -450,13 +482,31 @@
};
// Parameter for "find_block" calls:
- // Describes the difference between a public and private copy.
+ // Describes the difference between a public and backedge copy.
enum CreateOption {
create_public_copy,
- create_private_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:
@@ -470,15 +520,24 @@
int _trap_bci;
int _trap_index;
- // A reasonable approximation to pre-order, provided.to the client.
+ // pre_order, assigned at first visit. Used as block ID and "visited" tag
int _pre_order;
- // Has this block been cloned for some special purpose?
- bool _private_copy;
+ // 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;
// A pointer used for our internal work list
- Block* _next;
- bool _on_work_list;
+ Block* _next;
+ bool _on_work_list; // on the work list
+ Block* _rpo_next; // Reverse post order list
+
+ // Loop info
+ Loop* _loop; // nearest loop
+ bool _irreducible_entry; // entry to irreducible loop
+ bool _exception_entry; // entry to exception handler
ciBlock* ciblock() const { return _ciblock; }
StateVector* state() const { return _state; }
@@ -504,10 +563,11 @@
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_private_copy() const { return _private_copy; }
- void set_private_copy(bool z);
- int private_copy_count() const { return outer()->private_copy_count(ciblock()->index(), _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(); }
@@ -515,6 +575,20 @@
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,
@@ -524,13 +598,6 @@
return _successors;
}
- // Helper function for "successors" when making private copies of
- // loop heads for C2.
- Block * clone_loop_head(ciTypeFlow* analyzer,
- int branch_bci,
- Block* target,
- JsrSet* jsrs);
-
// Get the exceptional successors for this Block.
GrowableArray<Block*>* exceptions() {
if (_exceptions == NULL) {
@@ -584,17 +651,126 @@
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() && po >= 0, ""); _pre_order = po; }
+ 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(); }
- // A ranking used in determining order within the work list.
- bool is_simpler_than(Block* other);
+ // 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; }
+ 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
@@ -619,6 +795,12 @@
// 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.
@@ -627,8 +809,8 @@
// block factory
Block* get_block_for(int ciBlockIndex, JsrSet* jsrs, CreateOption option = create_public_copy);
- // How many of the blocks have the private_copy bit set?
- int private_copy_count(int ciBlockIndex, JsrSet* jsrs) const;
+ // 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.
@@ -651,11 +833,18 @@
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;
@@ -668,6 +857,15 @@
// 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;
@@ -677,6 +875,9 @@
// 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();
@@ -703,6 +904,15 @@
// 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();
@@ -711,4 +921,6 @@
void do_flow();
void print_on(outputStream* st) const PRODUCT_RETURN;
+
+ void rpo_print_on(outputStream* st) const PRODUCT_RETURN;
};