8007037: JSR 292: the VM_RedefineClasses::append_entry() should do cross-checks with indy operands

Summary: References from operands to CP entries and back must be correct after CP merge
Reviewed-by: coleenp, twisti
Contributed-by: serguei.spitsyn@oracle.com

src/share/vm/oops/constantPool.cpp

@@ -1043,24 +1043,13 @@ bool ConstantPool::compare_entry_to(int index1, constantPoolHandle cp2,
 
   case JVM_CONSTANT_InvokeDynamic:
   {
-    int k1 = invoke_dynamic_bootstrap_method_ref_index_at(index1);
-    int k2 = cp2->invoke_dynamic_bootstrap_method_ref_index_at(index2);
-    bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
-    if (!match)  return false;
-    k1 = invoke_dynamic_name_and_type_ref_index_at(index1);
-    k2 = cp2->invoke_dynamic_name_and_type_ref_index_at(index2);
-    match = compare_entry_to(k1, cp2, k2, CHECK_false);
-    if (!match)  return false;
-    int argc = invoke_dynamic_argument_count_at(index1);
-    if (argc == cp2->invoke_dynamic_argument_count_at(index2)) {
-      for (int j = 0; j < argc; j++) {
-        k1 = invoke_dynamic_argument_index_at(index1, j);
-        k2 = cp2->invoke_dynamic_argument_index_at(index2, j);
-        match = compare_entry_to(k1, cp2, k2, CHECK_false);
-        if (!match)  return false;
-      }
-      return true;           // got through loop; all elements equal
-    }
+    int k1 = invoke_dynamic_name_and_type_ref_index_at(index1);
+    int k2 = cp2->invoke_dynamic_name_and_type_ref_index_at(index2);
+    int i1 = invoke_dynamic_bootstrap_specifier_index(index1);
+    int i2 = cp2->invoke_dynamic_bootstrap_specifier_index(index2);
+    bool match = compare_entry_to(k1, cp2, k2, CHECK_false) &&
+                 compare_operand_to(i1, cp2, i2, CHECK_false);
+    return match;
   } break;
 
   case JVM_CONSTANT_String:
@@ -1095,6 +1084,80 @@ bool ConstantPool::compare_entry_to(int index1, constantPoolHandle cp2,
 } // end compare_entry_to()
 
 
+// Resize the operands array with delta_len and delta_size.
+// Used in RedefineClasses for CP merge.
+void ConstantPool::resize_operands(int delta_len, int delta_size, TRAPS) {
+  int old_len  = operand_array_length(operands());
+  int new_len  = old_len + delta_len;
+  int min_len  = (delta_len > 0) ? old_len : new_len;
+
+  int old_size = operands()->length();
+  int new_size = old_size + delta_size;
+  int min_size = (delta_size > 0) ? old_size : new_size;
+
+  ClassLoaderData* loader_data = pool_holder()->class_loader_data();
+  Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, new_size, CHECK);
+
+  // Set index in the resized array for existing elements only
+  for (int idx = 0; idx < min_len; idx++) {
+    int offset = operand_offset_at(idx);                       // offset in original array
+    operand_offset_at_put(new_ops, idx, offset + 2*delta_len); // offset in resized array
+  }
+  // Copy the bootstrap specifiers only
+  Copy::conjoint_memory_atomic(operands()->adr_at(2*old_len),
+                               new_ops->adr_at(2*new_len),
+                               (min_size - 2*min_len) * sizeof(u2));
+  // Explicitly deallocate old operands array.
+  // Note, it is not needed for 7u backport.
+  if ( operands() != NULL) { // the safety check
+    MetadataFactory::free_array<u2>(loader_data, operands());
+  }
+  set_operands(new_ops);
+} // end resize_operands()
+
+
+// Extend the operands array with the length and size of the ext_cp operands.
+// Used in RedefineClasses for CP merge.
+void ConstantPool::extend_operands(constantPoolHandle ext_cp, TRAPS) {
+  int delta_len = operand_array_length(ext_cp->operands());
+  if (delta_len == 0) {
+    return; // nothing to do
+  }
+  int delta_size = ext_cp->operands()->length();
+
+  assert(delta_len  > 0 && delta_size > 0, "extended operands array must be bigger");
+
+  if (operand_array_length(operands()) == 0) {
+    ClassLoaderData* loader_data = pool_holder()->class_loader_data();
+    Array<u2>* new_ops = MetadataFactory::new_array<u2>(loader_data, delta_size, CHECK);
+    // The first element index defines the offset of second part
+    operand_offset_at_put(new_ops, 0, 2*delta_len); // offset in new array
+    set_operands(new_ops);
+  } else {
+    resize_operands(delta_len, delta_size, CHECK);
+  }
+
+} // end extend_operands()
+
+
+// Shrink the operands array to a smaller array with new_len length.
+// Used in RedefineClasses for CP merge.
+void ConstantPool::shrink_operands(int new_len, TRAPS) {
+  int old_len = operand_array_length(operands());
+  if (new_len == old_len) {
+    return; // nothing to do
+  }
+  assert(new_len < old_len, "shrunken operands array must be smaller");
+
+  int free_base  = operand_next_offset_at(new_len - 1);
+  int delta_len  = new_len - old_len;
+  int delta_size = 2*delta_len + free_base - operands()->length();
+
+  resize_operands(delta_len, delta_size, CHECK);
+
+} // end shrink_operands()
+
+
 void ConstantPool::copy_operands(constantPoolHandle from_cp,
                                  constantPoolHandle to_cp,
                                  TRAPS) {
@@ -1357,6 +1420,46 @@ int ConstantPool::find_matching_entry(int pattern_i,
 } // end find_matching_entry()
 
 
+// Compare this constant pool's bootstrap specifier at idx1 to the constant pool
+// cp2's bootstrap specifier at idx2.
+bool ConstantPool::compare_operand_to(int idx1, constantPoolHandle cp2, int idx2, TRAPS) {
+  int k1 = operand_bootstrap_method_ref_index_at(idx1);
+  int k2 = cp2->operand_bootstrap_method_ref_index_at(idx2);
+  bool match = compare_entry_to(k1, cp2, k2, CHECK_false);
+
+  if (!match) {
+    return false;
+  }
+  int argc = operand_argument_count_at(idx1);
+  if (argc == cp2->operand_argument_count_at(idx2)) {
+    for (int j = 0; j < argc; j++) {
+      k1 = operand_argument_index_at(idx1, j);
+      k2 = cp2->operand_argument_index_at(idx2, j);
+      match = compare_entry_to(k1, cp2, k2, CHECK_false);
+      if (!match) {
+        return false;
+      }
+    }
+    return true;           // got through loop; all elements equal
+  }
+  return false;
+} // end compare_operand_to()
+
+// Search constant pool search_cp for a bootstrap specifier that matches
+// this constant pool's bootstrap specifier at pattern_i index.
+// Return the index of a matching bootstrap specifier or (-1) if there is no match.
+int ConstantPool::find_matching_operand(int pattern_i,
+                    constantPoolHandle search_cp, int search_len, TRAPS) {
+  for (int i = 0; i < search_len; i++) {
+    bool found = compare_operand_to(pattern_i, search_cp, i, CHECK_(-1));
+    if (found) {
+      return i;
+    }
+  }
+  return -1;  // bootstrap specifier not found; return unused index (-1)
+} // end find_matching_operand()
+
+
 #ifndef PRODUCT
 
 const char* ConstantPool::printable_name_at(int which) {

src/share/vm/oops/constantPool.hpp

@@ -567,6 +567,47 @@ class ConstantPool : public Metadata {
          _indy_argc_offset = 1,  // u2 argc
          _indy_argv_offset = 2   // u2 argv[argc]
   };
+
+  // These functions are used in RedefineClasses for CP merge
+
+  int operand_offset_at(int bootstrap_specifier_index) {
+    assert(0 <= bootstrap_specifier_index &&
+           bootstrap_specifier_index < operand_array_length(operands()),
+           "Corrupted CP operands");
+    return operand_offset_at(operands(), bootstrap_specifier_index);
+  }
+  int operand_bootstrap_method_ref_index_at(int bootstrap_specifier_index) {
+    int offset = operand_offset_at(bootstrap_specifier_index);
+    return operands()->at(offset + _indy_bsm_offset);
+  }
+  int operand_argument_count_at(int bootstrap_specifier_index) {
+    int offset = operand_offset_at(bootstrap_specifier_index);
+    int argc = operands()->at(offset + _indy_argc_offset);
+    return argc;
+  }
+  int operand_argument_index_at(int bootstrap_specifier_index, int j) {
+    int offset = operand_offset_at(bootstrap_specifier_index);
+    return operands()->at(offset + _indy_argv_offset + j);
+  }
+  int operand_next_offset_at(int bootstrap_specifier_index) {
+    int offset = operand_offset_at(bootstrap_specifier_index) + _indy_argv_offset
+                   + operand_argument_count_at(bootstrap_specifier_index);
+    return offset;
+  }
+  // Compare a bootsrap specifier in the operands arrays
+  bool compare_operand_to(int bootstrap_specifier_index1, constantPoolHandle cp2,
+                          int bootstrap_specifier_index2, TRAPS);
+  // Find a bootsrap specifier in the operands array
+  int find_matching_operand(int bootstrap_specifier_index, constantPoolHandle search_cp,
+                            int operands_cur_len, TRAPS);
+  // Resize the operands array with delta_len and delta_size
+  void resize_operands(int delta_len, int delta_size, TRAPS);
+  // Extend the operands array with the length and size of the ext_cp operands
+  void extend_operands(constantPoolHandle ext_cp, TRAPS);
+  // Shrink the operands array to a smaller array with new_len length
+  void shrink_operands(int new_len, TRAPS);
+
+
   int invoke_dynamic_bootstrap_method_ref_index_at(int which) {
     assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool");
     int op_base = invoke_dynamic_operand_base(which);

src/share/vm/prims/jvmtiRedefineClasses.cpp

@@ -415,20 +415,26 @@ void VM_RedefineClasses::append_entry(constantPoolHandle scratch_cp,
     // this is an indirect CP entry so it needs special handling
     case JVM_CONSTANT_InvokeDynamic:
     {
-      // TBD: cross-checks and possible extra appends into CP and bsm operands
-      // are needed as well. This issue is tracked by a separate bug 8007037.
-      int bss_idx = scratch_cp->invoke_dynamic_bootstrap_specifier_index(scratch_i);
-
-      int ref_i = scratch_cp->invoke_dynamic_name_and_type_ref_index_at(scratch_i);
-      int new_ref_i = find_or_append_indirect_entry(scratch_cp, ref_i, merge_cp_p,
+      // Index of the bootstrap specifier in the operands array
+      int old_bs_i = scratch_cp->invoke_dynamic_bootstrap_specifier_index(scratch_i);
+      int new_bs_i = find_or_append_operand(scratch_cp, old_bs_i, merge_cp_p,
+                                            merge_cp_length_p, THREAD);
+      // The bootstrap method NameAndType_info index
+      int old_ref_i = scratch_cp->invoke_dynamic_name_and_type_ref_index_at(scratch_i);
+      int new_ref_i = find_or_append_indirect_entry(scratch_cp, old_ref_i, merge_cp_p,
                                                     merge_cp_length_p, THREAD);
-      if (new_ref_i != ref_i) {
+      if (new_bs_i != old_bs_i) {
         RC_TRACE(0x00080000,
-                 ("InvokeDynamic entry@%d name_and_type ref_index change: %d to %d",
-                  *merge_cp_length_p, ref_i, new_ref_i));
+                 ("InvokeDynamic entry@%d bootstrap_method_attr_index change: %d to %d",
+                  *merge_cp_length_p, old_bs_i, new_bs_i));
+      }
+      if (new_ref_i != old_ref_i) {
+        RC_TRACE(0x00080000,
+                 ("InvokeDynamic entry@%d name_and_type_index change: %d to %d",
+                  *merge_cp_length_p, old_ref_i, new_ref_i));
       }
 
-      (*merge_cp_p)->invoke_dynamic_at_put(*merge_cp_length_p, bss_idx, new_ref_i);
+      (*merge_cp_p)->invoke_dynamic_at_put(*merge_cp_length_p, new_bs_i, new_ref_i);
       if (scratch_i != *merge_cp_length_p) {
         // The new entry in *merge_cp_p is at a different index than
         // the new entry in scratch_cp so we need to map the index values.
@@ -492,6 +498,105 @@ int VM_RedefineClasses::find_or_append_indirect_entry(constantPoolHandle scratch
 } // end find_or_append_indirect_entry()
 
 
+// Append a bootstrap specifier into the merge_cp operands that is semantically equal
+// to the scratch_cp operands bootstrap specifier passed by the old_bs_i index.
+// Recursively append new merge_cp entries referenced by the new bootstrap specifier.
+void VM_RedefineClasses::append_operand(constantPoolHandle scratch_cp, int old_bs_i,
+       constantPoolHandle *merge_cp_p, int *merge_cp_length_p, TRAPS) {
+
+  int old_ref_i = scratch_cp->operand_bootstrap_method_ref_index_at(old_bs_i);
+  int new_ref_i = find_or_append_indirect_entry(scratch_cp, old_ref_i, merge_cp_p,
+                                                merge_cp_length_p, THREAD);
+  if (new_ref_i != old_ref_i) {
+    RC_TRACE(0x00080000,
+             ("operands entry@%d bootstrap method ref_index change: %d to %d",
+              _operands_cur_length, old_ref_i, new_ref_i));
+  }
+
+  Array<u2>* merge_ops = (*merge_cp_p)->operands();
+  int new_bs_i = _operands_cur_length;
+  // We have _operands_cur_length == 0 when the merge_cp operands is empty yet.
+  // However, the operand_offset_at(0) was set in the extend_operands() call.
+  int new_base = (new_bs_i == 0) ? (*merge_cp_p)->operand_offset_at(0)
+                                 : (*merge_cp_p)->operand_next_offset_at(new_bs_i - 1);
+  int argc     = scratch_cp->operand_argument_count_at(old_bs_i);
+
+  ConstantPool::operand_offset_at_put(merge_ops, _operands_cur_length, new_base);
+  merge_ops->at_put(new_base++, new_ref_i);
+  merge_ops->at_put(new_base++, argc);
+
+  for (int i = 0; i < argc; i++) {
+    int old_arg_ref_i = scratch_cp->operand_argument_index_at(old_bs_i, i);
+    int new_arg_ref_i = find_or_append_indirect_entry(scratch_cp, old_arg_ref_i, merge_cp_p,
+                                                      merge_cp_length_p, THREAD);
+    merge_ops->at_put(new_base++, new_arg_ref_i);
+    if (new_arg_ref_i != old_arg_ref_i) {
+      RC_TRACE(0x00080000,
+               ("operands entry@%d bootstrap method argument ref_index change: %d to %d",
+                _operands_cur_length, old_arg_ref_i, new_arg_ref_i));
+    }
+  }
+  if (old_bs_i != _operands_cur_length) {
+    // The bootstrap specifier in *merge_cp_p is at a different index than
+    // that in scratch_cp so we need to map the index values.
+    map_operand_index(old_bs_i, new_bs_i);
+  }
+  _operands_cur_length++;
+} // end append_operand()
+
+
+int VM_RedefineClasses::find_or_append_operand(constantPoolHandle scratch_cp,
+      int old_bs_i, constantPoolHandle *merge_cp_p, int *merge_cp_length_p, TRAPS) {
+
+  int new_bs_i = old_bs_i; // bootstrap specifier index
+  bool match = (old_bs_i < _operands_cur_length) &&
+               scratch_cp->compare_operand_to(old_bs_i, *merge_cp_p, old_bs_i, THREAD);
+
+  if (!match) {
+    // forward reference in *merge_cp_p or not a direct match
+    int found_i = scratch_cp->find_matching_operand(old_bs_i, *merge_cp_p,
+                                                    _operands_cur_length, THREAD);
+    if (found_i != -1) {
+      guarantee(found_i != old_bs_i, "compare_operand_to() and find_matching_operand() disagree");
+      // found a matching operand somewhere else in *merge_cp_p so just need a mapping
+      new_bs_i = found_i;
+      map_operand_index(old_bs_i, found_i);
+    } else {
+      // no match found so we have to append this bootstrap specifier to *merge_cp_p
+      append_operand(scratch_cp, old_bs_i, merge_cp_p, merge_cp_length_p, THREAD);
+      new_bs_i = _operands_cur_length - 1;
+    }
+  }
+  return new_bs_i;
+} // end find_or_append_operand()
+
+
+void VM_RedefineClasses::finalize_operands_merge(constantPoolHandle merge_cp, TRAPS) {
+  if (merge_cp->operands() == NULL) {
+    return;
+  }
+  // Shrink the merge_cp operands
+  merge_cp->shrink_operands(_operands_cur_length, CHECK);
+
+  if (RC_TRACE_ENABLED(0x00040000)) {
+    // don't want to loop unless we are tracing
+    int count = 0;
+    for (int i = 1; i < _operands_index_map_p->length(); i++) {
+      int value = _operands_index_map_p->at(i);
+      if (value != -1) {
+        RC_TRACE_WITH_THREAD(0x00040000, THREAD,
+          ("operands_index_map[%d]: old=%d new=%d", count, i, value));
+        count++;
+      }
+    }
+  }
+  // Clean-up
+  _operands_index_map_p = NULL;
+  _operands_cur_length = 0;
+  _operands_index_map_count = 0;
+} // end finalize_operands_merge()
+
+
 jvmtiError VM_RedefineClasses::compare_and_normalize_class_versions(
              instanceKlassHandle the_class,
              instanceKlassHandle scratch_class) {
@@ -765,6 +870,31 @@ int VM_RedefineClasses::find_new_index(int old_index) {
 } // end find_new_index()
 
 
+// Find new bootstrap specifier index value for old bootstrap specifier index
+// value by seaching the index map. Returns unused index (-1) if there is
+// no mapped value for the old bootstrap specifier index.
+int VM_RedefineClasses::find_new_operand_index(int old_index) {
+  if (_operands_index_map_count == 0) {
+    // map is empty so nothing can be found
+    return -1;
+  }
+
+  if (old_index == -1 || old_index >= _operands_index_map_p->length()) {
+    // The old_index is out of range so it is not mapped.
+    // This should not happen in regular constant pool merging use.
+    return -1;
+  }
+
+  int value = _operands_index_map_p->at(old_index);
+  if (value == -1) {
+    // the old_index is not mapped
+    return -1;
+  }
+
+  return value;
+} // end find_new_operand_index()
+
+
 // Returns true if the current mismatch is due to a resolved/unresolved
 // class pair. Otherwise, returns false.
 bool VM_RedefineClasses::is_unresolved_class_mismatch(constantPoolHandle cp1,
@@ -1014,6 +1144,25 @@ void VM_RedefineClasses::map_index(constantPoolHandle scratch_cp,
 } // end map_index()
 
 
+// Map old_index to new_index as needed.
+void VM_RedefineClasses::map_operand_index(int old_index, int new_index) {
+  if (find_new_operand_index(old_index) != -1) {
+    // old_index is already mapped
+    return;
+  }
+
+  if (old_index == new_index) {
+    // no mapping is needed
+    return;
+  }
+
+  _operands_index_map_p->at_put(old_index, new_index);
+  _operands_index_map_count++;
+
+  RC_TRACE(0x00040000, ("mapped bootstrap specifier at index %d to %d", old_index, new_index));
+} // end map_index()
+
+
 // Merge old_cp and scratch_cp and return the results of the merge via
 // merge_cp_p. The number of entries in *merge_cp_p is returned via
 // merge_cp_length_p. The entries in old_cp occupy the same locations
@@ -1086,6 +1235,7 @@ bool VM_RedefineClasses::merge_constant_pools(constantPoolHandle old_cp,
     } // end for each old_cp entry
 
     ConstantPool::copy_operands(old_cp, *merge_cp_p, CHECK_0);
+    (*merge_cp_p)->extend_operands(scratch_cp, CHECK_0);
 
     // We don't need to sanity check that *merge_cp_length_p is within
     // *merge_cp_p bounds since we have the minimum on-entry check above.
@@ -1198,6 +1348,8 @@ bool VM_RedefineClasses::merge_constant_pools(constantPoolHandle old_cp,
         CHECK_0);
     }
 
+    finalize_operands_merge(*merge_cp_p, THREAD);
+
     RC_TRACE_WITH_THREAD(0x00020000, THREAD,
       ("after pass 1b: merge_cp_len=%d, scratch_i=%d, index_map_len=%d",
       *merge_cp_length_p, scratch_i, _index_map_count));
@@ -1270,6 +1422,11 @@ jvmtiError VM_RedefineClasses::merge_cp_and_rewrite(
   _index_map_count = 0;
   _index_map_p = new intArray(scratch_cp->length(), -1);
 
+  _operands_cur_length = ConstantPool::operand_array_length(old_cp->operands());
+  _operands_index_map_count = 0;
+  _operands_index_map_p = new intArray(
+    ConstantPool::operand_array_length(scratch_cp->operands()), -1);
+
   // reference to the cp holder is needed for copy_operands()
   merge_cp->set_pool_holder(scratch_class());
   bool result = merge_constant_pools(old_cp, scratch_cp, &merge_cp,
@@ -1400,7 +1557,6 @@ bool VM_RedefineClasses::rewrite_cp_refs(instanceKlassHandle scratch_class,
   return true;
 } // end rewrite_cp_refs()
 
-
 // Rewrite constant pool references in the methods.
 bool VM_RedefineClasses::rewrite_cp_refs_in_methods(
        instanceKlassHandle scratch_class, TRAPS) {

src/share/vm/prims/jvmtiRedefineClasses.hpp

@@ -359,8 +359,15 @@ class VM_RedefineClasses: public VM_Operation {
   // _index_map_p contains any entries.
   int                         _index_map_count;
   intArray *                  _index_map_p;
+
+  // _operands_index_map_count is just an optimization for knowing if
+  // _operands_index_map_p contains any entries.
+  int                         _operands_cur_length;
+  int                         _operands_index_map_count;
+  intArray *                  _operands_index_map_p;
+
   // ptr to _class_count scratch_classes
-  Klass**                   _scratch_classes;
+  Klass**                     _scratch_classes;
   jvmtiError                  _res;
 
   // Performance measurement support. These timers do not cover all
@@ -422,12 +429,19 @@ class VM_RedefineClasses: public VM_Operation {
   // Support for constant pool merging (these routines are in alpha order):
   void append_entry(constantPoolHandle scratch_cp, int scratch_i,
     constantPoolHandle *merge_cp_p, int *merge_cp_length_p, TRAPS);
+  void append_operand(constantPoolHandle scratch_cp, int scratch_bootstrap_spec_index,
+    constantPoolHandle *merge_cp_p, int *merge_cp_length_p, TRAPS);
+  void finalize_operands_merge(constantPoolHandle merge_cp, TRAPS);
   int find_or_append_indirect_entry(constantPoolHandle scratch_cp, int scratch_i,
     constantPoolHandle *merge_cp_p, int *merge_cp_length_p, TRAPS);
+  int find_or_append_operand(constantPoolHandle scratch_cp, int scratch_bootstrap_spec_index,
+    constantPoolHandle *merge_cp_p, int *merge_cp_length_p, TRAPS);
   int find_new_index(int old_index);
+  int find_new_operand_index(int old_bootstrap_spec_index);
   bool is_unresolved_class_mismatch(constantPoolHandle cp1, int index1,
     constantPoolHandle cp2, int index2);
   void map_index(constantPoolHandle scratch_cp, int old_index, int new_index);
+  void map_operand_index(int old_bootstrap_spec_index, int new_bootstrap_spec_index);
   bool merge_constant_pools(constantPoolHandle old_cp,
     constantPoolHandle scratch_cp, constantPoolHandle *merge_cp_p,
     int *merge_cp_length_p, TRAPS);