Update V8 to version 4.1.0.21

This is a cherry-pick of all commits up to and including the
4.1.0.21 cherry-pick in Chromium.

Original commit message:

Version 4.1.0.21 (cherry-pick)

Merged 206e9136bde0f2b5ae8cb77afbb1e7833e5bd412

Unlink pages from the space page list after evacuation.

BUG=430201
LOG=N
R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/953813002

Cr-Commit-Position: refs/branch-heads/4.1@{#22}
Cr-Branched-From: 2e08d2a7aa9d65d269d8c57aba82eb38a8cb0a18-refs/heads/candidates@{#25353}

---

FPIIM-449

Change-Id: I8c23c7bbb70772b4858fe8a47b64fa97ee0d1f8c
diff --git a/src/ppc/simulator-ppc.h b/src/ppc/simulator-ppc.h
new file mode 100644
index 0000000..98fe9a5
--- /dev/null
+++ b/src/ppc/simulator-ppc.h
@@ -0,0 +1,413 @@
+// Copyright 2014 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+
+// Declares a Simulator for PPC instructions if we are not generating a native
+// PPC binary. This Simulator allows us to run and debug PPC code generation on
+// regular desktop machines.
+// V8 calls into generated code by "calling" the CALL_GENERATED_CODE macro,
+// which will start execution in the Simulator or forwards to the real entry
+// on a PPC HW platform.
+
+#ifndef V8_PPC_SIMULATOR_PPC_H_
+#define V8_PPC_SIMULATOR_PPC_H_
+
+#include "src/allocation.h"
+
+#if !defined(USE_SIMULATOR)
+// Running without a simulator on a native ppc platform.
+
+namespace v8 {
+namespace internal {
+
+// When running without a simulator we call the entry directly.
+#define CALL_GENERATED_CODE(entry, p0, p1, p2, p3, p4) \
+  (entry(p0, p1, p2, p3, p4))
+
+typedef int (*ppc_regexp_matcher)(String*, int, const byte*, const byte*, int*,
+                                  int, Address, int, void*, Isolate*);
+
+
+// Call the generated regexp code directly. The code at the entry address
+// should act as a function matching the type ppc_regexp_matcher.
+// The ninth argument is a dummy that reserves the space used for
+// the return address added by the ExitFrame in native calls.
+#define CALL_GENERATED_REGEXP_CODE(entry, p0, p1, p2, p3, p4, p5, p6, p7, p8) \
+  (FUNCTION_CAST<ppc_regexp_matcher>(entry)(p0, p1, p2, p3, p4, p5, p6, p7,   \
+                                            NULL, p8))
+
+// The stack limit beyond which we will throw stack overflow errors in
+// generated code. Because generated code on ppc uses the C stack, we
+// just use the C stack limit.
+class SimulatorStack : public v8::internal::AllStatic {
+ public:
+  static inline uintptr_t JsLimitFromCLimit(v8::internal::Isolate* isolate,
+                                            uintptr_t c_limit) {
+    USE(isolate);
+    return c_limit;
+  }
+
+  static inline uintptr_t RegisterCTryCatch(uintptr_t try_catch_address) {
+    return try_catch_address;
+  }
+
+  static inline void UnregisterCTryCatch() {}
+};
+}
+}  // namespace v8::internal
+
+#else  // !defined(USE_SIMULATOR)
+// Running with a simulator.
+
+#include "src/assembler.h"
+#include "src/hashmap.h"
+#include "src/ppc/constants-ppc.h"
+
+namespace v8 {
+namespace internal {
+
+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 PPCDebugger;
+  enum Register {
+    no_reg = -1,
+    r0 = 0,
+    sp,
+    r2,
+    r3,
+    r4,
+    r5,
+    r6,
+    r7,
+    r8,
+    r9,
+    r10,
+    r11,
+    r12,
+    r13,
+    r14,
+    r15,
+    r16,
+    r17,
+    r18,
+    r19,
+    r20,
+    r21,
+    r22,
+    r23,
+    r24,
+    r25,
+    r26,
+    r27,
+    r28,
+    r29,
+    r30,
+    fp,
+    kNumGPRs = 32,
+    d0 = 0,
+    d1,
+    d2,
+    d3,
+    d4,
+    d5,
+    d6,
+    d7,
+    d8,
+    d9,
+    d10,
+    d11,
+    d12,
+    d13,
+    d14,
+    d15,
+    d16,
+    d17,
+    d18,
+    d19,
+    d20,
+    d21,
+    d22,
+    d23,
+    d24,
+    d25,
+    d26,
+    d27,
+    d28,
+    d29,
+    d30,
+    d31,
+    kNumFPRs = 32
+  };
+
+  explicit Simulator(Isolate* isolate);
+  ~Simulator();
+
+  // The currently executing Simulator instance. Potentially there can be one
+  // for each native thread.
+  static Simulator* current(v8::internal::Isolate* isolate);
+
+  // Accessors for register state.
+  void set_register(int reg, intptr_t value);
+  intptr_t get_register(int reg) const;
+  double get_double_from_register_pair(int reg);
+  void set_d_register_from_double(int dreg, const double dbl) {
+    DCHECK(dreg >= 0 && dreg < kNumFPRs);
+    fp_registers_[dreg] = dbl;
+  }
+  double get_double_from_d_register(int dreg) { return fp_registers_[dreg]; }
+
+  // Special case of set_register and get_register to access the raw PC value.
+  void set_pc(intptr_t value);
+  intptr_t get_pc() const;
+
+  Address get_sp() {
+    return reinterpret_cast<Address>(static_cast<intptr_t>(get_register(sp)));
+  }
+
+  // Accessor to the internal simulator stack area.
+  uintptr_t StackLimit() const;
+
+  // Executes PPC instructions until the PC reaches end_sim_pc.
+  void Execute();
+
+  // Call on program start.
+  static void Initialize(Isolate* isolate);
+
+  // V8 generally calls into generated JS code with 5 parameters and into
+  // generated RegExp code with 7 parameters. This is a convenience function,
+  // which sets up the simulator state and grabs the result on return.
+  intptr_t Call(byte* entry, int argument_count, ...);
+  // Alternative: call a 2-argument double function.
+  void CallFP(byte* entry, double d0, double d1);
+  int32_t CallFPReturnsInt(byte* entry, double d0, double d1);
+  double CallFPReturnsDouble(byte* entry, double d0, double d1);
+
+  // Push an address onto the JS stack.
+  uintptr_t PushAddress(uintptr_t address);
+
+  // Pop an address from the JS stack.
+  uintptr_t PopAddress();
+
+  // Debugger input.
+  void set_last_debugger_input(char* input);
+  char* last_debugger_input() { return last_debugger_input_; }
+
+  // ICache checking.
+  static void FlushICache(v8::internal::HashMap* i_cache, void* start,
+                          size_t size);
+
+  // Returns true if pc register contains one of the 'special_values' defined
+  // below (bad_lr, end_sim_pc).
+  bool has_bad_pc() const;
+
+ private:
+  enum special_values {
+    // Known bad pc value to ensure that the simulator does not execute
+    // without being properly setup.
+    bad_lr = -1,
+    // A pc value used to signal the simulator to stop execution.  Generally
+    // the lr is set to this value on transition from native C code to
+    // simulated execution, so that the simulator can "return" to the native
+    // C code.
+    end_sim_pc = -2
+  };
+
+  // Unsupported instructions use Format to print an error and stop execution.
+  void Format(Instruction* instr, const char* format);
+
+  // Helper functions to set the conditional flags in the architecture state.
+  bool CarryFrom(int32_t left, int32_t right, int32_t carry = 0);
+  bool BorrowFrom(int32_t left, int32_t right);
+  bool OverflowFrom(int32_t alu_out, int32_t left, int32_t right,
+                    bool addition);
+
+  // Helper functions to decode common "addressing" modes
+  int32_t GetShiftRm(Instruction* instr, bool* carry_out);
+  int32_t GetImm(Instruction* instr, bool* carry_out);
+  void ProcessPUW(Instruction* instr, int num_regs, int operand_size,
+                  intptr_t* start_address, intptr_t* end_address);
+  void HandleRList(Instruction* instr, bool load);
+  void HandleVList(Instruction* inst);
+  void SoftwareInterrupt(Instruction* instr);
+
+  // Stop helper functions.
+  inline bool isStopInstruction(Instruction* instr);
+  inline bool isWatchedStop(uint32_t bkpt_code);
+  inline bool isEnabledStop(uint32_t bkpt_code);
+  inline void EnableStop(uint32_t bkpt_code);
+  inline void DisableStop(uint32_t bkpt_code);
+  inline void IncreaseStopCounter(uint32_t bkpt_code);
+  void PrintStopInfo(uint32_t code);
+
+  // Read and write memory.
+  inline uint8_t ReadBU(intptr_t addr);
+  inline int8_t ReadB(intptr_t addr);
+  inline void WriteB(intptr_t addr, uint8_t value);
+  inline void WriteB(intptr_t addr, int8_t value);
+
+  inline uint16_t ReadHU(intptr_t addr, Instruction* instr);
+  inline int16_t ReadH(intptr_t addr, Instruction* instr);
+  // Note: Overloaded on the sign of the value.
+  inline void WriteH(intptr_t addr, uint16_t value, Instruction* instr);
+  inline void WriteH(intptr_t addr, int16_t value, Instruction* instr);
+
+  inline uint32_t ReadWU(intptr_t addr, Instruction* instr);
+  inline int32_t ReadW(intptr_t addr, Instruction* instr);
+  inline void WriteW(intptr_t addr, uint32_t value, Instruction* instr);
+  inline void WriteW(intptr_t addr, int32_t value, Instruction* instr);
+
+  intptr_t* ReadDW(intptr_t addr);
+  void WriteDW(intptr_t addr, int64_t value);
+
+  void Trace(Instruction* instr);
+  void SetCR0(intptr_t result, bool setSO = false);
+  void ExecuteBranchConditional(Instruction* instr);
+  void ExecuteExt1(Instruction* instr);
+  bool ExecuteExt2_10bit(Instruction* instr);
+  bool ExecuteExt2_9bit_part1(Instruction* instr);
+  void ExecuteExt2_9bit_part2(Instruction* instr);
+  void ExecuteExt2(Instruction* instr);
+  void ExecuteExt4(Instruction* instr);
+#if V8_TARGET_ARCH_PPC64
+  void ExecuteExt5(Instruction* instr);
+#endif
+  void ExecuteGeneric(Instruction* instr);
+
+  // Executes one instruction.
+  void ExecuteInstruction(Instruction* instr);
+
+  // ICache.
+  static void CheckICache(v8::internal::HashMap* i_cache, Instruction* instr);
+  static void FlushOnePage(v8::internal::HashMap* i_cache, intptr_t start,
+                           int size);
+  static CachePage* GetCachePage(v8::internal::HashMap* i_cache, void* page);
+
+  // Runtime call support.
+  static void* RedirectExternalReference(
+      void* external_function, v8::internal::ExternalReference::Type type);
+
+  // Handle arguments and return value for runtime FP functions.
+  void GetFpArgs(double* x, double* y, intptr_t* z);
+  void SetFpResult(const double& result);
+  void TrashCallerSaveRegisters();
+
+  void CallInternal(byte* entry);
+
+  // Architecture state.
+  // Saturating instructions require a Q flag to indicate saturation.
+  // There is currently no way to read the CPSR directly, and thus read the Q
+  // flag, so this is left unimplemented.
+  intptr_t registers_[kNumGPRs];
+  int32_t condition_reg_;
+  int32_t fp_condition_reg_;
+  intptr_t special_reg_lr_;
+  intptr_t special_reg_pc_;
+  intptr_t special_reg_ctr_;
+  int32_t special_reg_xer_;
+
+  double fp_registers_[kNumFPRs];
+
+  // Simulator support.
+  char* stack_;
+  bool pc_modified_;
+  int icount_;
+
+  // Debugger input.
+  char* last_debugger_input_;
+
+  // Icache simulation
+  v8::internal::HashMap* i_cache_;
+
+  // Registered breakpoints.
+  Instruction* break_pc_;
+  Instr break_instr_;
+
+  v8::internal::Isolate* isolate_;
+
+  // A stop is watched if its code is less than kNumOfWatchedStops.
+  // Only watched stops support enabling/disabling and the counter feature.
+  static const uint32_t kNumOfWatchedStops = 256;
+
+  // Breakpoint is disabled if bit 31 is set.
+  static const uint32_t kStopDisabledBit = 1 << 31;
+
+  // A stop is enabled, meaning the simulator will stop when meeting the
+  // instruction, if bit 31 of watched_stops_[code].count is unset.
+  // The value watched_stops_[code].count & ~(1 << 31) indicates how many times
+  // the breakpoint was hit or gone through.
+  struct StopCountAndDesc {
+    uint32_t count;
+    char* desc;
+  };
+  StopCountAndDesc watched_stops_[kNumOfWatchedStops];
+};
+
+
+// When running with the simulator transition into simulated execution at this
+// point.
+#define CALL_GENERATED_CODE(entry, p0, p1, p2, p3, p4)                    \
+  reinterpret_cast<Object*>(Simulator::current(Isolate::Current())->Call( \
+      FUNCTION_ADDR(entry), 5, (intptr_t)p0, (intptr_t)p1, (intptr_t)p2,  \
+      (intptr_t)p3, (intptr_t)p4))
+
+#define CALL_GENERATED_REGEXP_CODE(entry, p0, p1, p2, p3, p4, p5, p6, p7, p8) \
+  Simulator::current(Isolate::Current())                                      \
+      ->Call(entry, 10, (intptr_t)p0, (intptr_t)p1, (intptr_t)p2,             \
+             (intptr_t)p3, (intptr_t)p4, (intptr_t)p5, (intptr_t)p6,          \
+             (intptr_t)p7, (intptr_t)NULL, (intptr_t)p8)
+
+
+// The simulator has its own stack. Thus it has a different stack limit from
+// the C-based native code.  Setting the c_limit to indicate a very small
+// stack cause stack overflow errors, since the simulator ignores the input.
+// This is unlikely to be an issue in practice, though it might cause testing
+// trouble down the line.
+class SimulatorStack : public v8::internal::AllStatic {
+ public:
+  static inline uintptr_t JsLimitFromCLimit(v8::internal::Isolate* isolate,
+                                            uintptr_t c_limit) {
+    return Simulator::current(isolate)->StackLimit();
+  }
+
+  static inline uintptr_t RegisterCTryCatch(uintptr_t try_catch_address) {
+    Simulator* sim = Simulator::current(Isolate::Current());
+    return sim->PushAddress(try_catch_address);
+  }
+
+  static inline void UnregisterCTryCatch() {
+    Simulator::current(Isolate::Current())->PopAddress();
+  }
+};
+}
+}  // namespace v8::internal
+
+#endif  // !defined(USE_SIMULATOR)
+#endif  // V8_PPC_SIMULATOR_PPC_H_