X64 Crankshaft: Fix error in pushed register indices for safepoints. Fixes i...

src/x64/macro-assembler-x64.h

Index: src/x64/macro-assembler-x64.h
===================================================================
--- src/x64/macro-assembler-x64.h	(revision 6775)
+++ src/x64/macro-assembler-x64.h	(working copy)
@@ -171,7 +171,8 @@
   void PushSafepointRegisters() { Pushad(); }
   void PopSafepointRegisters() { Popad(); }
   static int SafepointRegisterStackIndex(int reg_code) {
-    return kSafepointPushRegisterIndices[reg_code];
+    return kRegistersPushedByPushad - 1 -
+        kSafepointPushRegisterIndices[reg_code];
   }
 
 
@@ -966,6 +967,8 @@
   // Order general registers are pushed by Pushad.
   // rax, rcx, rdx, rbx, rsi, rdi, r8, r9, r11, r12, r14.
   static int kSafepointPushRegisterIndices[Register::kNumRegisters];
+  static const int kRegistersPushedByPushad = 11;
+
   bool generating_stub_;
   bool allow_stub_calls_;