- Add the ability to protect VirtualMemory.

runtime/vm/heap.cc

Index: runtime/vm/heap.cc
===================================================================
--- runtime/vm/heap.cc	(revision 9969)
+++ runtime/vm/heap.cc	(working copy)
@@ -226,6 +226,13 @@
 }
 
 
+void Heap::Protect(VirtualMemory::Protection mode) {
+  new_space_->Protect(mode);
+  old_space_->Protect(mode);
+  code_space_->Protect(mode);

[siva, 2012/07/27 01:55:00]

This seems weird here as we independently set the code pages to executable.
If somebody calls heap()->Protect(kReadWrite);
hoping to make the new space and old space non executable they would
inadvertently set the code pages also as non executable.

[Ivan Posva, 2012/07/27 18:02:56]

Done.

+}
+
+
 uword Heap::TopAddress() {
   return reinterpret_cast<uword>(new_space_->TopAddress());
 }