Contribution of PowerPC port.

src/debug.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/api.h"
 #include "src/arguments.h"
 #include "src/bootstrapper.h"
 #include "src/code-stubs.h"
@@ skipping 1875 matching lines @@
              reinterpret_cast<intptr_t>(new_code->instruction_start()) +
              new_code->instruction_size(),
              new_code->instruction_size(),
              reinterpret_cast<intptr_t>(frame->pc()),
              reinterpret_cast<intptr_t>(new_pc));
     }
 
     // Patch the return address to return into the code with
     // debug break slots.
     frame->set_pc(new_pc);
+    if (FLAG_enable_ool_constant_pool) {

[danno, 2014/07/29 13:24:08]

Is this a change that is unrelated to the port (seems it is), if so, can you
please factor out into a separate patch?

[andrew_low, 2014/07/30 13:27:05]

Created https://codereview.chromium.org/430523002 to cover this commit

On 2014/07/29 13:24:08, danno wrote:

+      frame->set_constant_pool(new_code->constant_pool());
+    }
   }
 }
 
 
 class ActiveFunctionsCollector : public ThreadVisitor {
  public:
   explicit ActiveFunctionsCollector(List<Handle<JSFunction> >* active_functions,
                                     Object* active_code_marker)
       : active_functions_(active_functions),
         active_code_marker_(active_code_marker) { }
@@ skipping 404 matching lines @@
   Handle<Code> original_code(debug_info->original_code());
 #ifdef DEBUG
   // Get the code which is actually executing.
   Handle<Code> frame_code(frame->LookupCode());
   ASSERT(frame_code.is_identical_to(code));
 #endif
 
   // Find the call address in the running code. This address holds the call to
   // either a DebugBreakXXX or to the debug break return entry code if the
   // break point is still active after processing the break point.
+#if V8_TARGET_ARCH_PPC
+  // PPC has variable length call sequence
+  Address addr = Assembler::target_address_from_return_address(frame->pc());
+#else
   Address addr = frame->pc() - Assembler::kPatchDebugBreakSlotReturnOffset;

[danno, 2014/07/29 13:24:08]

Could you please abstract this to Assembler? There probably should be new
method: Assembler::break_address_from_break_address which is implemented as
"frame->pc() - Assembler::kPatchDebugBreakSlotReturnOffset" on all platforms
except PPC. That would remove the #if def here.

[andrew_low, 2014/07/30 13:27:05]

Done.

+#endif
 
   // Check if the location is at JS exit or debug break slot.
   bool at_js_return = false;
   bool break_at_js_return_active = false;
   bool at_debug_break_slot = false;
   RelocIterator it(debug_info->code());
   while (!it.done() && !at_js_return && !at_debug_break_slot) {
     if (RelocInfo::IsJSReturn(it.rinfo()->rmode())) {
       at_js_return = (it.rinfo()->pc() ==
           addr - Assembler::kPatchReturnSequenceAddressOffset);
       break_at_js_return_active = it.rinfo()->IsPatchedReturnSequence();
     }
     if (RelocInfo::IsDebugBreakSlot(it.rinfo()->rmode())) {
       at_debug_break_slot = (it.rinfo()->pc() ==
           addr - Assembler::kPatchDebugBreakSlotAddressOffset);
     }
     it.next();
   }
 
   // Handle the jump to continue execution after break point depending on the
   // break location.
   if (at_js_return) {
-    // If the break point as return is still active jump to the corresponding
+    // If the break point at return is still active jump to the corresponding
     // place in the original code. If not the break point was removed during
     // break point processing.
     if (break_at_js_return_active) {
       addr += original_code->instruction_start() - code->instruction_start();
     }
 
     // Move back to where the call instruction sequence started.
     after_break_target_ = addr - Assembler::kPatchReturnSequenceAddressOffset;
   } else if (at_debug_break_slot) {
     // Address of where the debug break slot starts.
@@ skipping 47 matching lines @@
   }
   Handle<DebugInfo> debug_info = GetDebugInfo(shared);
   Handle<Code> code(debug_info->code());
 #ifdef DEBUG
   // Get the code which is actually executing.
   Handle<Code> frame_code(frame->LookupCode());
   ASSERT(frame_code.is_identical_to(code));
 #endif
 
   // Find the call address in the running code.
+#if V8_TARGET_ARCH_PPC

[danno, 2014/07/29 13:24:08]

See above

[andrew_low, 2014/07/30 13:27:05]

Done.

+  // PPC has variable length call sequence
+  Address addr = Assembler::target_address_from_return_address(frame->pc());
+#else
   Address addr = frame->pc() - Assembler::kPatchDebugBreakSlotReturnOffset;
+#endif
 
   // Check if the location is at JS return.
   RelocIterator it(debug_info->code());
   while (!it.done()) {
     if (RelocInfo::IsJSReturn(it.rinfo()->rmode())) {
       return (it.rinfo()->pc() ==
           addr - Assembler::kPatchReturnSequenceAddressOffset);
     }
     it.next();
   }
@@ skipping 975 matching lines @@
   logger_->DebugEvent("Put", message.text());
 }
 
 
 void LockingCommandMessageQueue::Clear() {
   base::LockGuard<base::Mutex> lock_guard(&mutex_);
   queue_.Clear();
 }
 
 } }  // namespace v8::internal