--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/share/vm/opto/idealKit.cpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,503 @@
+/*
+ * Copyright 2005-2006 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+#include "incls/_precompiled.incl"
+#include "incls/_idealKit.cpp.incl"
+
+// Static initialization
+
+// This declares the position where vars are kept in the cvstate
+// For some degree of consistency we use the TypeFunc enum to
+// soak up spots in the inputs even though we only use early Control
+// and Memory slots. (So far.)
+const uint IdealKit::first_var = TypeFunc::Parms + 1;
+
+//----------------------------IdealKit-----------------------------------------
+IdealKit::IdealKit(PhaseGVN &gvn, Node* control, Node* mem, bool delay_all_transforms) :
+  _gvn(gvn), C(gvn.C) {
+  _initial_ctrl = control;
+  _initial_memory = mem;
+  _delay_all_transforms = delay_all_transforms;
+  _var_ct = 0;
+  _cvstate = NULL;
+  // We can go memory state free or else we need the entire memory state
+  assert(mem == NULL || mem->Opcode() == Op_MergeMem, "memory must be pre-split");
+  int init_size = 5;
+  _pending_cvstates = new (C->node_arena()) GrowableArray<Node*>(C->node_arena(), init_size, 0, 0);
+  _delay_transform  = new (C->node_arena()) GrowableArray<Node*>(C->node_arena(), init_size, 0, 0);
+  DEBUG_ONLY(_state = new (C->node_arena()) GrowableArray<int>(C->node_arena(), init_size, 0, 0));
+}
+
+//-------------------------------if_then-------------------------------------
+// Create:  if(left relop right)
+//          /  \
+//   iffalse    iftrue
+// Push the iffalse cvstate onto the stack. The iftrue becomes the current cvstate.
+void IdealKit::if_then(Node* left, BoolTest::mask relop,
+                       Node* right, float prob, float cnt, bool push_new_state) {
+  assert((state() & (BlockS|LoopS|IfThenS|ElseS)), "bad state for new If");
+  Node* bol;
+  if (left->bottom_type()->isa_ptr() == NULL) {
+    if (left->bottom_type()->isa_int() != NULL) {
+      bol = Bool(CmpI(left, right), relop);
+    } else {
+      assert(left->bottom_type()->isa_long() != NULL, "what else?");
+      bol = Bool(CmpL(left, right), relop);
+    }
+
+  } else {
+    bol = Bool(CmpP(left, right), relop);
+  }
+  // Delay gvn.tranform on if-nodes until construction is finished
+  // to prevent a constant bool input from discarding a control output.
+  IfNode* iff = delay_transform(new (C, 2) IfNode(ctrl(), bol, prob, cnt))->as_If();
+  Node* then  = IfTrue(iff);
+  Node* elsen = IfFalse(iff);
+  Node* else_cvstate = copy_cvstate();
+  else_cvstate->set_req(TypeFunc::Control, elsen);
+  _pending_cvstates->push(else_cvstate);
+  DEBUG_ONLY(if (push_new_state) _state->push(IfThenS));
+  set_ctrl(then);
+}
+
+//-------------------------------else_-------------------------------------
+// Pop the else cvstate off the stack, and push the (current) then cvstate.
+// The else cvstate becomes the current cvstate.
+void IdealKit::else_() {
+  assert(state() == IfThenS, "bad state for new Else");
+  Node* else_cvstate = _pending_cvstates->pop();
+  DEBUG_ONLY(_state->pop());
+  // save current (then) cvstate for later use at endif
+  _pending_cvstates->push(_cvstate);
+  DEBUG_ONLY(_state->push(ElseS));
+  _cvstate = else_cvstate;
+}
+
+//-------------------------------end_if-------------------------------------
+// Merge the "then" and "else" cvstates.
+//
+// The if_then() pushed the current state for later use
+// as the initial state for a future "else" clause.  The
+// current state then became the initial state for the
+// then clause.  If an "else" clause was encountered, it will
+// pop the top state and use it for it's initial state.
+// It will also push the current state (the state at the end of
+// the "then" clause) for latter use at the end_if.
+//
+// At the endif, the states are:
+// 1) else exists a) current state is end of "else" clause
+//                b) top stack state is end of "then" clause
+//
+// 2) no else:    a) current state is end of "then" clause
+//                b) top stack state is from the "if_then" which
+//                   would have been the initial state of the else.
+//
+// Merging the states is accomplished by:
+//   1) make a label for the merge
+//   2) terminate the current state with a goto to the label
+//   3) pop the top state from the stack and make it the
+//        current state
+//   4) bind the label at the current state.  Binding a label
+//        terminates the current state with a goto to the
+//        label and makes the label's state the current state.
+//
+void IdealKit::end_if() {
+  assert(state() & (IfThenS|ElseS), "bad state for new Endif");
+  Node* lab = make_label(1);
+
+  // Node* join_state = _pending_cvstates->pop();
+                  /* merging, join */
+  goto_(lab);
+  _cvstate = _pending_cvstates->pop();
+
+  bind(lab);
+  DEBUG_ONLY(_state->pop());
+}
+
+//-------------------------------loop-------------------------------------
+// Create the loop head portion (*) of:
+//  *     iv = init
+//  *  top: (region node)
+//  *     if (iv relop limit) {
+//           loop body
+//           i = i + 1
+//           goto top
+//  *     } else // exits loop
+//
+// Pushes the loop top cvstate first, then the else (loop exit) cvstate
+// onto the stack.
+void IdealKit::loop(IdealVariable& iv, Node* init, BoolTest::mask relop, Node* limit, float prob, float cnt) {
+  assert((state() & (BlockS|LoopS|IfThenS|ElseS)), "bad state for new loop");
+  set(iv, init);
+  Node* head = make_label(1);
+  bind(head);
+  _pending_cvstates->push(head); // push for use at end_loop
+  _cvstate = copy_cvstate();
+  if_then(value(iv), relop, limit, prob, cnt, false /* no new state */);
+  DEBUG_ONLY(_state->push(LoopS));
+  assert(ctrl()->is_IfTrue(), "true branch stays in loop");
+  assert(_pending_cvstates->top()->in(TypeFunc::Control)->is_IfFalse(), "false branch exits loop");
+}
+
+//-------------------------------end_loop-------------------------------------
+// Creates the goto top label.
+// Expects the else (loop exit) cvstate to be on top of the
+// stack, and the loop top cvstate to be 2nd.
+void IdealKit::end_loop() {
+  assert((state() == LoopS), "bad state for new end_loop");
+  Node* exit = _pending_cvstates->pop();
+  Node* head = _pending_cvstates->pop();
+  goto_(head);
+  clear(head);
+  DEBUG_ONLY(_state->pop());
+  _cvstate = exit;
+}
+
+//-------------------------------make_label-------------------------------------
+// Creates a label.  The number of goto's
+// must be specified (which should be 1 less than
+// the number of precedessors.)
+Node* IdealKit::make_label(int goto_ct) {
+  assert(_cvstate != NULL, "must declare variables before labels");
+  Node* lab = new_cvstate();
+  int sz = 1 + goto_ct + 1 /* fall thru */;
+  Node* reg = delay_transform(new (C, sz) RegionNode(sz));
+  lab->init_req(TypeFunc::Control, reg);
+  return lab;
+}
+
+//-------------------------------bind-------------------------------------
+// Bind a label at the current cvstate by simulating
+// a goto to the label.
+void IdealKit::bind(Node* lab) {
+  goto_(lab, true /* bind */);
+  _cvstate = lab;
+}
+
+//-------------------------------goto_-------------------------------------
+// Make the current cvstate a predecessor of the label,
+// creating phi's to merge values.  If bind is true and
+// this is not the last control edge, then ensure that
+// all live values have phis created. Used to create phis
+// at loop-top regions.
+void IdealKit::goto_(Node* lab, bool bind) {
+  Node* reg = lab->in(TypeFunc::Control);
+  // find next empty slot in region
+  uint slot = 1;
+  while (slot < reg->req() && reg->in(slot) != NULL) slot++;
+  assert(slot < reg->req(), "too many gotos");
+  // If this is last predecessor, then don't force phi creation
+  if (slot == reg->req() - 1) bind = false;
+  reg->init_req(slot, ctrl());
+  assert(first_var + _var_ct == _cvstate->req(), "bad _cvstate size");
+  for (uint i = first_var; i < _cvstate->req(); i++) {
+
+    // l is the value of var reaching the label. Could be a single value
+    // reaching the label, or a phi that merges multiples values reaching
+    // the label.  The latter is true if the label's input: in(..) is
+    // a phi whose control input is the region node for the label.
+
+    Node* l = lab->in(i);
+    // Get the current value of the var
+    Node* m = _cvstate->in(i);
+    // If the var went unused no need for a phi
+    if (m == NULL) {
+      continue;
+    } else if (l == NULL || m == l) {
+      // Only one unique value "m" is known to reach this label so a phi
+      // is not yet necessary unless:
+      //    the label is being bound and all predecessors have not been seen,
+      //    in which case "bind" will be true.
+      if (bind) {
+        m = promote_to_phi(m, reg);
+      }
+      // Record the phi/value used for this var in the label's cvstate
+      lab->set_req(i, m);
+    } else {
+      // More than one value for the variable reaches this label so
+      // a create a phi if one does not already exist.
+      if (!was_promoted_to_phi(l, reg)) {
+        l = promote_to_phi(l, reg);
+        lab->set_req(i, l);
+      }
+      // Record in the phi, the var's value from the current state
+      l->set_req(slot, m);
+    }
+  }
+  do_memory_merge(_cvstate, lab);
+  stop();
+}
+
+//-----------------------------promote_to_phi-----------------------------------
+Node* IdealKit::promote_to_phi(Node* n, Node* reg) {
+  assert(!was_promoted_to_phi(n, reg), "n already promoted to phi on this region");
+  // Get a conservative type for the phi
+  const BasicType bt = n->bottom_type()->basic_type();
+  const Type* ct = Type::get_const_basic_type(bt);
+  return delay_transform(PhiNode::make(reg, n, ct));
+}
+
+//-----------------------------declares_done-----------------------------------
+void IdealKit::declares_done() {
+  _cvstate = new_cvstate();   // initialize current cvstate
+  set_ctrl(_initial_ctrl);    // initialize control in current cvstate
+  set_all_memory(_initial_memory);// initialize memory in current cvstate
+  DEBUG_ONLY(_state->push(BlockS));
+}
+
+//-----------------------------transform-----------------------------------
+Node* IdealKit::transform(Node* n) {
+  if (_delay_all_transforms) {
+    return delay_transform(n);
+  } else {
+    return gvn().transform(n);
+  }
+}
+
+//-----------------------------delay_transform-----------------------------------
+Node* IdealKit::delay_transform(Node* n) {
+  gvn().set_type(n, n->bottom_type());
+  _delay_transform->push(n);
+  return n;
+}
+
+//-----------------------------new_cvstate-----------------------------------
+Node* IdealKit::new_cvstate() {
+  uint sz = _var_ct + first_var;
+  return new (C, sz) Node(sz);
+}
+
+//-----------------------------copy_cvstate-----------------------------------
+Node* IdealKit::copy_cvstate() {
+  Node* ns = new_cvstate();
+  for (uint i = 0; i < ns->req(); i++) ns->init_req(i, _cvstate->in(i));
+  // We must clone memory since it will be updated as we do stores.
+  ns->set_req(TypeFunc::Memory, MergeMemNode::make(C, ns->in(TypeFunc::Memory)));
+  return ns;
+}
+
+//-----------------------------clear-----------------------------------
+void IdealKit::clear(Node* m) {
+  for (uint i = 0; i < m->req(); i++) m->set_req(i, NULL);
+}
+
+//-----------------------------drain_delay_transform----------------------------
+void IdealKit::drain_delay_transform() {
+  while (_delay_transform->length() > 0) {
+    Node* n = _delay_transform->pop();
+    gvn().transform(n);
+    if (!gvn().is_IterGVN()) {
+      C->record_for_igvn(n);
+    }
+  }
+}
+
+//-----------------------------IdealVariable----------------------------
+IdealVariable::IdealVariable(IdealKit &k) {
+  k.declare(this);
+}
+
+Node* IdealKit::memory(uint alias_idx) {
+  MergeMemNode* mem = merged_memory();
+  Node* p = mem->memory_at(alias_idx);
+  _gvn.set_type(p, Type::MEMORY);  // must be mapped
+  return p;
+}
+
+void IdealKit::set_memory(Node* mem, uint alias_idx) {
+  merged_memory()->set_memory_at(alias_idx, mem);
+}
+
+//----------------------------- make_load ----------------------------
+Node* IdealKit::load(Node* ctl,
+                     Node* adr,
+                     const Type* t,
+                     BasicType bt,
+                     int adr_idx,
+                     bool require_atomic_access) {
+
+  assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
+  const TypePtr* adr_type = NULL; // debug-mode-only argument
+  debug_only(adr_type = C->get_adr_type(adr_idx));
+  Node* mem = memory(adr_idx);
+  Node* ld;
+  if (require_atomic_access && bt == T_LONG) {
+    ld = LoadLNode::make_atomic(C, ctl, mem, adr, adr_type, t);
+  } else {
+    ld = LoadNode::make(C, ctl, mem, adr, adr_type, t, bt);
+  }
+  return transform(ld);
+}
+
+Node* IdealKit::store(Node* ctl, Node* adr, Node *val, BasicType bt,
+                                int adr_idx,
+                                bool require_atomic_access) {
+  assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
+  const TypePtr* adr_type = NULL;
+  debug_only(adr_type = C->get_adr_type(adr_idx));
+  Node *mem = memory(adr_idx);
+  Node* st;
+  if (require_atomic_access && bt == T_LONG) {
+    st = StoreLNode::make_atomic(C, ctl, mem, adr, adr_type, val);
+  } else {
+    st = StoreNode::make(C, ctl, mem, adr, adr_type, val, bt);
+  }
+  st = transform(st);
+  set_memory(st, adr_idx);
+
+  return st;
+}
+
+// Card mark store. Must be ordered so that it will come after the store of
+// the oop.
+Node* IdealKit::storeCM(Node* ctl, Node* adr, Node *val, Node* oop_store,
+                        BasicType bt,
+                        int adr_idx) {
+  assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
+  const TypePtr* adr_type = NULL;
+  debug_only(adr_type = C->get_adr_type(adr_idx));
+  Node *mem = memory(adr_idx);
+
+  // Add required edge to oop_store, optimizer does not support precedence edges.
+  // Convert required edge to precedence edge before allocation.
+  Node* st = new (C, 5) StoreCMNode(ctl, mem, adr, adr_type, val, oop_store);
+
+  st = transform(st);
+  set_memory(st, adr_idx);
+
+  return st;
+}
+
+//---------------------------- do_memory_merge --------------------------------
+// The memory from one merging cvstate needs to be merged with the memory for another
+// join cvstate. If the join cvstate doesn't have a merged memory yet then we
+// can just copy the state from the merging cvstate
+
+// Merge one slow path into the rest of memory.
+void IdealKit::do_memory_merge(Node* merging, Node* join) {
+
+  // Get the region for the join state
+  Node* join_region = join->in(TypeFunc::Control);
+  assert(join_region != NULL, "join region must exist");
+  if (join->in(TypeFunc::Memory) == NULL ) {
+    join->set_req(TypeFunc::Memory,  merging->in(TypeFunc::Memory));
+    return;
+  }
+
+  // The control flow for merging must have already been attached to the join region
+  // we need its index for the phis.
+  uint slot;
+  for (slot = 1; slot < join_region->req() ; slot ++ ) {
+    if (join_region->in(slot) == merging->in(TypeFunc::Control)) break;
+  }
+  assert(slot !=  join_region->req(), "edge must already exist");
+
+  MergeMemNode* join_m    = join->in(TypeFunc::Memory)->as_MergeMem();
+  MergeMemNode* merging_m = merging->in(TypeFunc::Memory)->as_MergeMem();
+
+  // join_m should be an ancestor mergemem of merging
+  // Slow path memory comes from the current map (which is from a slow call)
+  // Fast path/null path memory comes from the call's input
+
+  // Merge the other fast-memory inputs with the new slow-default memory.
+  // for (MergeMemStream mms(merged_memory(), fast_mem->as_MergeMem()); mms.next_non_empty2(); ) {
+  for (MergeMemStream mms(join_m, merging_m); mms.next_non_empty2(); ) {
+    Node* join_slice = mms.force_memory();
+    Node* merging_slice = mms.memory2();
+    if (join_slice != merging_slice) {
+      PhiNode* phi;
+      // bool new_phi = false;
+      // Is the phi for this slice one that we created for this join region or simply
+      // one we copied? If it is ours then add
+      if (join_slice->is_Phi() && join_slice->as_Phi()->region() == join_region) {
+        phi = join_slice->as_Phi();
+      } else {
+        // create the phi with join_slice filling supplying memory for all of the
+        // control edges to the join region
+        phi = PhiNode::make(join_region, join_slice, Type::MEMORY, mms.adr_type(C));
+        phi = (PhiNode*) delay_transform(phi);
+        // gvn().set_type(phi, Type::MEMORY);
+        // new_phi = true;
+      }
+      // Now update the phi with the slice for the merging slice
+      phi->set_req(slot, merging_slice/* slow_path, slow_slice */);
+      // this updates join_m with the phi
+      mms.set_memory(phi);
+    }
+  }
+}
+
+
+//----------------------------- make_call  ----------------------------
+// Trivial runtime call
+void IdealKit::make_leaf_call(const TypeFunc *slow_call_type,
+                              address slow_call,
+                              const char *leaf_name,
+                              Node* parm0,
+                              Node* parm1,
+                              Node* parm2) {
+
+  // We only handle taking in RawMem and modifying RawMem
+  const TypePtr* adr_type = TypeRawPtr::BOTTOM;
+  uint adr_idx = C->get_alias_index(adr_type);
+
+  // Clone initial memory
+  MergeMemNode* cloned_mem =  MergeMemNode::make(C, merged_memory());
+
+  // Slow-path leaf call
+  int size = slow_call_type->domain()->cnt();
+  CallNode *call =  (CallNode*)new (C, size) CallLeafNode( slow_call_type, slow_call, leaf_name, adr_type);
+
+  // Set fixed predefined input arguments
+  call->init_req( TypeFunc::Control, ctrl() );
+  call->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
+  // Narrow memory as only memory input
+  call->init_req( TypeFunc::Memory , memory(adr_idx));
+  call->init_req( TypeFunc::FramePtr, top() /* frameptr() */ );
+  call->init_req( TypeFunc::ReturnAdr, top() );
+
+  if (parm0 != NULL)  call->init_req(TypeFunc::Parms+0, parm0);
+  if (parm1 != NULL)  call->init_req(TypeFunc::Parms+1, parm1);
+  if (parm2 != NULL)  call->init_req(TypeFunc::Parms+2, parm2);
+
+  // Node *c = _gvn.transform(call);
+  call = (CallNode *) _gvn.transform(call);
+  Node *c = call; // dbx gets confused with call call->dump()
+
+  // Slow leaf call has no side-effects, sets few values
+
+  set_ctrl(transform( new (C, 1) ProjNode(call,TypeFunc::Control) ));
+
+  // Set the incoming clone of memory as current memory
+  set_all_memory(cloned_mem);
+
+  // Make memory for the call
+  Node* mem = _gvn.transform( new (C, 1) ProjNode(call, TypeFunc::Memory) );
+
+  // Set the RawPtr memory state only.
+  set_memory(mem, adr_idx);
+
+  assert(C->alias_type(call->adr_type()) == C->alias_type(adr_type),
+         "call node must be constructed correctly");
+}