Introduce kRegisterSize, kPCOnStackSize and kFPOnStackSize constants

src/deoptimizer.h

Index: src/deoptimizer.h
===================================================================
--- src/deoptimizer.h	(revision 15739)
+++ src/deoptimizer.h	(working copy)
@@ -510,6 +510,22 @@
     *GetFrameSlotPointer(offset) = value;
   }
 
+  void SetCallerPc(unsigned offset, intptr_t value) {

[danno, 2013/07/18 10:51:24]

A difference copy of this routine should be in the platform-specific files.

[haitao.feng, 2013/07/18 12:18:20]

Done.

+    if (kPCOnStackSize != kPointerSize) {
+      ASSERT(kPCOnStackSize == kPointerSize + kPointerSize);
+      SetFrameSlot(offset + kPointerSize, 0);

[danno, 2013/07/18 10:51:24]

This assumes little endianess, I would much prefer to just have a different copy
of this short routine on each platform. 

[haitao.feng, 2013/07/18 12:18:20]

Done.

+    }
+    SetFrameSlot(offset, value);
+  }
+
+  void SetCallerFp(unsigned offset, intptr_t value) {

[danno, 2013/07/18 10:51:24]

Same as above, there should be a different implementation of this function in
each deoptimizer-XXX file for each platform.

[haitao.feng, 2013/07/18 12:18:20]

Done.

+    if (kFPOnStackSize != kPointerSize) {
+      ASSERT(kFPOnStackSize == kPointerSize + kPointerSize);
+      SetFrameSlot(offset + kPointerSize, 0);
+    }
+    SetFrameSlot(offset, value);
+  }
+
   intptr_t GetRegister(unsigned n) const {
     ASSERT(n < ARRAY_SIZE(registers_));
     return registers_[n];