VM: Use PC offset instead of absolute PC in exception handler info.

runtime/vm/object.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/cpu.h"
@@ skipping 10923 matching lines @@
 }
 
 
 intptr_t ExceptionHandlers::num_entries() const {
   return raw_ptr()->num_entries_;
 }
 
 
 void ExceptionHandlers::SetHandlerInfo(intptr_t try_index,
                                        intptr_t outer_try_index,
-                                       intptr_t handler_pc,
+                                       uword handler_pc_offset,
                                        bool needs_stacktrace,
                                        bool has_catch_all) const {
   ASSERT((try_index >= 0) && (try_index < num_entries()));
   NoGCScope no_gc;
   RawExceptionHandlers::HandlerInfo* info =
       UnsafeMutableNonPointer(&raw_ptr()->data()[try_index]);
   info->outer_try_index = outer_try_index;
-  info->handler_pc = handler_pc;
+  info->handler_pc_offset = handler_pc_offset;

[srdjan, 2015/01/23 16:55:28]

Could you add an assert that on 64-bit handler_pc_offset content is not bigger
than uin32_t?

[Florian Schneider, 2015/01/26 15:28:53]

Done. I didn't use Utils::IsUint because it does not compile cross-platform for
unsigned types.

   info->needs_stacktrace = needs_stacktrace;
   info->has_catch_all = has_catch_all;
 }
 
 void ExceptionHandlers::GetHandlerInfo(
     intptr_t try_index,
     RawExceptionHandlers::HandlerInfo* info) const {
   ASSERT((try_index >= 0) && (try_index < num_entries()));
   ASSERT(info != NULL);
   *info = raw_ptr()->data()[try_index];
 }
 
 
-intptr_t ExceptionHandlers::HandlerPC(intptr_t try_index) const {
+uword ExceptionHandlers::HandlerPCOffset(intptr_t try_index) const {
   ASSERT((try_index >= 0) && (try_index < num_entries()));
-  return raw_ptr()->data()[try_index].handler_pc;
+  return raw_ptr()->data()[try_index].handler_pc_offset;
 }
 
 
 intptr_t ExceptionHandlers::OuterTryIndex(intptr_t try_index) const {
   ASSERT((try_index >= 0) && (try_index < num_entries()));
   return raw_ptr()->data()[try_index].outer_try_index;
 }
 
 
 bool ExceptionHandlers::NeedsStacktrace(intptr_t try_index) const {
@@ skipping 67 matching lines @@
                         " types) (outer %" Pd ")\n";
   const char* kFormat2 = "  %d. %s\n";
   intptr_t len = 1;  // Trailing '\0'.
   for (intptr_t i = 0; i < num_entries(); i++) {
     GetHandlerInfo(i, &info);
     handled_types = GetHandledTypes(i);
     ASSERT(!handled_types.IsNull());
     const intptr_t num_types = handled_types.Length();
     len += OS::SNPrint(NULL, 0, kFormat,
                        i,
-                       info.handler_pc,
+                       info.handler_pc_offset,
                        num_types,
                        info.outer_try_index);
     for (int k = 0; k < num_types; k++) {
       type ^= handled_types.At(k);
       ASSERT(!type.IsNull());
       len += OS::SNPrint(NULL, 0, kFormat2, k, type.ToCString());
     }
   }
   // Allocate the buffer.
   char* buffer = Isolate::Current()->current_zone()->Alloc<char>(len);
   // Layout the fields in the buffer.
   intptr_t num_chars = 0;
   for (intptr_t i = 0; i < num_entries(); i++) {
     GetHandlerInfo(i, &info);
     handled_types = GetHandledTypes(i);
     const intptr_t num_types = handled_types.Length();
     num_chars += OS::SNPrint((buffer + num_chars),
                              (len - num_chars),
                              kFormat,
                              i,
-                             info.handler_pc,
+                             info.handler_pc_offset,
                              num_types,
                              info.outer_try_index);
     for (int k = 0; k < num_types; k++) {
       type ^= handled_types.At(k);
       num_chars += OS::SNPrint((buffer + num_chars),
                                (len - num_chars),
                                kFormat2, k, type.ToCString());
     }
   }
   return buffer;
@@ skipping 9438 matching lines @@
   return tag_label.ToCString();
 }
 
 
 void UserTag::PrintJSONImpl(JSONStream* stream, bool ref) const {
   Instance::PrintJSONImpl(stream, ref);
 }
 
 
 }  // namespace dart