[futex] Allow debugger to break in the middle of a futexWait

src/execution.h

Index: src/execution.h
diff --git a/src/execution.h b/src/execution.h
index 2c07a64aaecc5409064ba1bc5eaf2f2edcf73880..b3ffed1ceb5c9596d16d5ed1d310ed30fd900f69 100644
--- a/src/execution.h
+++ b/src/execution.h
@@ -16,6 +16,15 @@ namespace internal {
 // Forward declarations.
 class JSRegExp;
 
+
+// Whether to handle a DebugBreak in a function that is not normally subject to
+// debugging (e.g. a builtin).
+enum BreakInNonDebuggableFlag {
+  DontBreakInNonDebuggable,
+  BreakInNonDebuggable,
+};
+
+
 class Execution final : public AllStatic {
  public:
   // Call a function, the caller supplies a receiver and an array
@@ -199,7 +208,8 @@ class StackGuard final {
 
   // If the stack guard is triggered, but it is not an actual
   // stack overflow, then handle the interruption accordingly.
-  Object* HandleInterrupts();
+  Object* HandleInterrupts(
+      BreakInNonDebuggableFlag flag = DontBreakInNonDebuggable);

[Michael Starzinger, 2015/08/31 21:52:21]

Hmpf! I realize that Yang suggested this approach, but this gives me the
shivers. Now execution.h contains both debugger and futex semantics. I am not
comfortable with this approach at all and would have actually preferred your
first patch set over this.

Yang, do you still think this second patch set is cleaner?

   void HandleGCInterrupt();
 
  private: