Update V8 to r4588

We're using WebKit r58033, as used by
http://src.chromium.org/svn/releases/5.0.387.0/DEPS
This requires http://v8.googlecode.com/svn/trunk@4465 but this version has a
crashing bug for ARM. Instead we use http://v8.googlecode.com/svn/trunk@4588,
which is used by http://src.chromium.org/svn/releases/6.0.399.0/DEPS

Note that a trivial bug fix was required in arm/codegen-arm.cc. This is guarded
with ANDROID. See http://code.google.com/p/v8/issues/detail?id=703

Change-Id: I459647a8286c4f8c7405f0c5581ecbf051a6f1e8
diff --git a/src/arm/simulator-arm.h b/src/arm/simulator-arm.h
index 1973730..91614ea 100644
--- a/src/arm/simulator-arm.h
+++ b/src/arm/simulator-arm.h
@@ -89,11 +89,43 @@
 
 
 #include "constants-arm.h"
+#include "hashmap.h"
 
 
 namespace assembler {
 namespace arm {
 
+class CachePage {
+ public:
+  static const int LINE_VALID = 0;
+  static const int LINE_INVALID = 1;
+
+  static const int kPageShift = 12;
+  static const int kPageSize = 1 << kPageShift;
+  static const int kPageMask = kPageSize - 1;
+  static const int kLineShift = 2;  // The cache line is only 4 bytes right now.
+  static const int kLineLength = 1 << kLineShift;
+  static const int kLineMask = kLineLength - 1;
+
+  CachePage() {
+    memset(&validity_map_, LINE_INVALID, sizeof(validity_map_));
+  }
+
+  char* ValidityByte(int offset) {
+    return &validity_map_[offset >> kLineShift];
+  }
+
+  char* CachedData(int offset) {
+    return &data_[offset];
+  }
+
+ private:
+  char data_[kPageSize];   // The cached data.
+  static const int kValidityMapSize = kPageSize >> kLineShift;
+  char validity_map_[kValidityMapSize];  // One byte per line.
+};
+
+
 class Simulator {
  public:
   friend class Debugger;
@@ -162,6 +194,9 @@
   // Pop an address from the JS stack.
   uintptr_t PopAddress();
 
+  // ICache checking.
+  static void FlushICache(void* start, size_t size);
+
  private:
   enum special_values {
     // Known bad pc value to ensure that the simulator does not execute
@@ -231,9 +266,19 @@
   void DecodeTypeVFP(Instr* instr);
   void DecodeType6CoprocessorIns(Instr* instr);
 
+  void DecodeVMOVBetweenCoreAndSinglePrecisionRegisters(Instr* instr);
+  void DecodeVCMP(Instr* instr);
+  void DecodeVCVTBetweenDoubleAndSingle(Instr* instr);
+  void DecodeVCVTBetweenFloatingPointAndInteger(Instr* instr);
+
   // Executes one instruction.
   void InstructionDecode(Instr* instr);
 
+  // ICache.
+  static void CheckICache(Instr* instr);
+  static void FlushOnePage(intptr_t start, int size);
+  static CachePage* GetCachePage(void* page);
+
   // Runtime call support.
   static void* RedirectExternalReference(void* external_function,
                                          bool fp_return);
@@ -271,6 +316,9 @@
   int icount_;
   static bool initialized_;
 
+  // Icache simulation
+  static v8::internal::HashMap* i_cache_;
+
   // Registered breakpoints.
   Instr* break_pc_;
   instr_t break_instr_;