Contribution of PowerPC port.

src/debug.cc

Index: src/debug.cc
diff --git a/src/debug.cc b/src/debug.cc
index 3586a1836db64cf8ae8f721af0b6bdf33bbd5982..6e726fb9f60243ae0abf3453bcad764ef4d24e40 100644
--- a/src/debug.cc
+++ b/src/debug.cc
@@ -1893,6 +1893,9 @@ static void RedirectActivationsToRecompiledCodeOnThread(
     // 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());
+    }
   }
 }
 
@@ -2317,7 +2320,12 @@ void Debug::SetAfterBreakTarget(JavaScriptFrame* frame) {
   // 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;
@@ -2340,7 +2348,7 @@ void Debug::SetAfterBreakTarget(JavaScriptFrame* frame) {
   // 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) {
@@ -2408,7 +2416,12 @@ bool Debug::IsBreakAtReturn(JavaScriptFrame* frame) {
 #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());