src/share/vm/opto/postaloc.cpp

rev 2647 : 7087453: PhaseChaitin::yank_if_dead() should handle MachTemp inputs
Summary: PhaseChaitin::yank_if_dead() should be able to handle MachTemp inputs as a special case and yank them.
Reviewed-by:

@@ -70,30 +70,47 @@
   // we must have discovered that it was not a callee save
   // else we would have returned.
   return i == limit;
 }
 
-
-
-//------------------------------yank_if_dead-----------------------------------
-// Removed an edge from 'old'.  Yank if dead.  Return adjustment counts to
-// iterators in the current block.
-int PhaseChaitin::yank_if_dead( Node *old, Block *current_block, Node_List *value, Node_List *regnd ) {
+//------------------------------yank-----------------------------------
+// Helper function for yank_if_dead
+int PhaseChaitin::yank( Node *old, Block *current_block, Node_List *value, Node_List *regnd ) {
   int blk_adjust=0;
-  while (old->outcnt() == 0 && old != C->top()) {
     Block *oldb = _cfg._bbs[old->_idx];
     oldb->find_remove(old);
     // Count 1 if deleting an instruction from the current block
     if( oldb == current_block ) blk_adjust++;
     _cfg._bbs.map(old->_idx,NULL);
     OptoReg::Name old_reg = lrgs(n2lidx(old)).reg();
     if( regnd && (*regnd)[old_reg]==old ) { // Instruction is currently available?
       value->map(old_reg,NULL);  // Yank from value/regnd maps
       regnd->map(old_reg,NULL);  // This register's value is now unknown
     }
-    assert(old->req() <= 2, "can't handle more inputs");
-    Node *tmp = old->req() > 1 ? old->in(1) : NULL;
+  return blk_adjust;
+}
+
+//------------------------------yank_if_dead-----------------------------------
+// Removed an edge from 'old'.  Yank if dead.  Return adjustment counts to
+// iterators in the current block.
+int PhaseChaitin::yank_if_dead( Node *old, Block *current_block, Node_List *value, Node_List *regnd ) {
+  int blk_adjust=0;
+  while (old->outcnt() == 0 && old != C->top()) {
+    blk_adjust += yank(old, current_block, value, regnd);
+
+    Node *tmp = NULL;
+    for (uint i = 1; i < old->req(); i++) {
+      if (old->in(i)->is_MachTemp()) {
+        Node* machtmp = old->in(i);
+        assert(machtmp->outcnt() == 1, "expected for a MachTemp");
+        blk_adjust += yank(machtmp, current_block, value, regnd);
+        machtmp->disconnect_inputs(NULL);
+      } else {
+        assert(tmp == NULL, "can't handle more non MachTemp inputs");
+        tmp = old->in(i);
+      }
+    }
     old->disconnect_inputs(NULL);
     if( !tmp ) break;
     old = tmp;
   }
   return blk_adjust;