hotspot/src/cpu/x86/vm/frame_x86.inline.hpp

rev 611 : Merge

@@ -1,10 +1,7 @@
-#ifdef USE_PRAGMA_IDENT_HDR
-#pragma ident "@(#)frame_x86.inline.hpp 1.76 07/09/17 09:35:34 JVM"
-#endif
 /*
- * Copyright 1997-2007 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright 1997-2008 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.

@@ -73,19 +70,24 @@
 inline frame::frame(intptr_t* sp, intptr_t* fp) {
   _sp = sp;
   _unextended_sp = sp;
   _fp = fp;
   _pc = (address)(sp[-1]);
-  assert(_pc != NULL, "no pc?");
+
+  // Here's a sticky one. This constructor can be called via AsyncGetCallTrace
+  // when last_Java_sp is non-null but the pc fetched is junk. If we are truly
+  // unlucky the junk value could be to a zombied method and we'll die on the
+  // find_blob call. This is also why we can have no asserts on the validity
+  // of the pc we find here. AsyncGetCallTrace -> pd_get_top_frame_for_signal_handler
+  // -> pd_last_frame should use a specialized version of pd_last_frame which could
+  // call a specilaized frame constructor instead of this one.
+  // Then we could use the assert below. However this assert is of somewhat dubious
+  // value.
+  // assert(_pc != NULL, "no pc?");
+
   _cb = CodeCache::find_blob(_pc);
-  // In case of native stubs, the pc retreived here might be 
-  // wrong. (the _last_native_pc will have the right value)
-  // So do not put add any asserts on the _pc here.
-
-  // QQQ The above comment is wrong and has been wrong for years. This constructor
-  // should (and MUST) not be called in that situation. In the native situation
-  // the pc should be supplied to the constructor.
+
   _deopt_state = not_deoptimized;
   if (_cb != NULL && _cb->is_nmethod() && ((nmethod*)_cb)->is_deopt_pc(_pc)) {
     _pc = (((nmethod*)_cb)->get_original_pc(this));
     _deopt_state = is_deoptimized;
   } else {

@@ -155,11 +157,11 @@
   return &(get_interpreterState()->_locals);
 }
 
 inline intptr_t* frame::interpreter_frame_bcx_addr() const {
   assert(is_interpreted_frame(), "must be interpreted");
-  return (jint*) &(get_interpreterState()->_bcp);
+  return (intptr_t*) &(get_interpreterState()->_bcp);
 }
 
 
 // Constant pool cache
 

@@ -175,11 +177,11 @@
   return &(get_interpreterState()->_method);
 }
 
 inline intptr_t* frame::interpreter_frame_mdx_addr() const {
   assert(is_interpreted_frame(), "must be interpreted");
-  return (jint*) &(get_interpreterState()->_mdx);
+  return (intptr_t*) &(get_interpreterState()->_mdx);
 }
 
 // top of expression stack
 inline intptr_t* frame::interpreter_frame_tos_address() const {
   assert(is_interpreted_frame(), "wrong frame type");

@@ -287,6 +289,5 @@
 }
 
 inline void frame::set_saved_oop_result(RegisterMap* map, oop obj) {
   *((oop*) map->location(rax->as_VMReg())) = obj;
 }
-