Merge 6168:6800 from bleeding_edge to experimental/gc branch.

src/arm/macro-assembler-arm.h

Index: src/arm/macro-assembler-arm.h
===================================================================
--- src/arm/macro-assembler-arm.h	(revision 6800)
+++ src/arm/macro-assembler-arm.h	(working copy)
@@ -33,6 +33,9 @@
 namespace v8 {
 namespace internal {
 
+// Forward declaration.
+class PostCallGenerator;
+
 // ----------------------------------------------------------------------------
 // Static helper functions
 
@@ -42,6 +45,12 @@
 }
 
 
+static inline Operand SmiUntagOperand(Register object) {
+  return Operand(object, ASR, kSmiTagSize);
+}
+
+
+
 // Give alias names to registers
 const Register cp = { 8 };  // JavaScript context pointer
 const Register roots = { 10 };  // Roots array pointer.
@@ -136,7 +145,7 @@
   // scratch can be object itself, but it will be clobbered.
   void InNewSpace(Register object,
                   Register scratch,
-                  Condition cc,  // eq for new space, ne otherwise
+                  Condition cond,  // eq for new space, ne otherwise
                   Label* branch);
 
 
@@ -230,7 +239,14 @@
   // RegList constant kSafepointSavedRegisters.
   void PushSafepointRegisters();
   void PopSafepointRegisters();
+  void PushSafepointRegistersAndDoubles();
+  void PopSafepointRegistersAndDoubles();
+  void StoreToSafepointRegisterSlot(Register reg);
+  void StoreToSafepointRegistersAndDoublesSlot(Register reg);
+  void LoadFromSafepointRegisterSlot(Register reg);
   static int SafepointRegisterStackIndex(int reg_code);
+  static MemOperand SafepointRegisterSlot(Register reg);
+  static MemOperand SafepointRegistersAndDoublesSlot(Register reg);
 
   // Load two consecutive registers with two consecutive memory locations.
   void Ldrd(Register dst1,
@@ -244,6 +260,30 @@
             const MemOperand& dst,
             Condition cond = al);
 
+  // Clear specified FPSCR bits.
+  void ClearFPSCRBits(const uint32_t bits_to_clear,
+                      const Register scratch,
+                      const Condition cond = al);
+
+  // Compare double values and move the result to the normal condition flags.
+  void VFPCompareAndSetFlags(const DwVfpRegister src1,
+                             const DwVfpRegister src2,
+                             const Condition cond = al);
+  void VFPCompareAndSetFlags(const DwVfpRegister src1,
+                             const double src2,
+                             const Condition cond = al);
+
+  // Compare double values and then load the fpscr flags to a register.
+  void VFPCompareAndLoadFlags(const DwVfpRegister src1,
+                              const DwVfpRegister src2,
+                              const Register fpscr_flags,
+                              const Condition cond = al);
+  void VFPCompareAndLoadFlags(const DwVfpRegister src1,
+                              const double src2,
+                              const Register fpscr_flags,
+                              const Condition cond = al);
+
+
   // ---------------------------------------------------------------------------
   // Activation frames
 
@@ -254,13 +294,13 @@
   void LeaveConstructFrame() { LeaveFrame(StackFrame::CONSTRUCT); }
 
   // Enter exit frame.
-  // Expects the number of arguments in register r0 and
-  // the builtin function to call in register r1. Exits with argc in
-  // r4, argv in r6, and and the builtin function to call in r5.
-  void EnterExitFrame(bool save_doubles);
+  // stack_space - extra stack space, used for alignment before call to C.
+  void EnterExitFrame(bool save_doubles, int stack_space = 0);
 
   // Leave the current exit frame. Expects the return value in r0.
-  void LeaveExitFrame(bool save_doubles);
+  // Expect the number of values, pushed prior to the exit frame, to
+  // remove in a register (or no_reg, if there is nothing to remove).
+  void LeaveExitFrame(bool save_doubles, Register argument_count);
 
   // Get the actual activation frame alignment for target environment.
   static int ActivationFrameAlignment();
@@ -282,7 +322,8 @@
   void InvokeCode(Register code,
                   const ParameterCount& expected,
                   const ParameterCount& actual,
-                  InvokeFlag flag);
+                  InvokeFlag flag,
+                  PostCallGenerator* post_call_generator = NULL);
 
   void InvokeCode(Handle<Code> code,
                   const ParameterCount& expected,
@@ -294,7 +335,8 @@
   // current context to the context in the function before invoking.
   void InvokeFunction(Register function,
                       const ParameterCount& actual,
-                      InvokeFlag flag);
+                      InvokeFlag flag,
+                      PostCallGenerator* post_call_generator = NULL);
 
   void InvokeFunction(JSFunction* function,
                       const ParameterCount& actual,
@@ -332,6 +374,13 @@
   // Must preserve the result register.
   void PopTryHandler();
 
+  // Passes thrown value (in r0) to the handler of top of the try handler chain.
+  void Throw(Register value);
+
+  // Propagates an uncatchable exception to the top of the current JS stack's
+  // handler chain.
+  void ThrowUncatchable(UncatchableExceptionType type, Register value);
+
   // ---------------------------------------------------------------------------
   // Inline caching support
 
@@ -380,12 +429,13 @@
   // ---------------------------------------------------------------------------
   // Allocation support
 
-  // Allocate an object in new space. The object_size is specified in words (not
-  // bytes). If the new space is exhausted control continues at the gc_required
-  // label. The allocated object is returned in result. If the flag
-  // tag_allocated_object is true the result is tagged as as a heap object. All
-  // registers are clobbered also when control continues at the gc_required
-  // label.
+  // Allocate an object in new space. The object_size is specified
+  // either in bytes or in words if the allocation flag SIZE_IN_WORDS
+  // is passed. If the new space is exhausted control continues at the
+  // gc_required label. The allocated object is returned in result. If
+  // the flag tag_allocated_object is true the result is tagged as as
+  // a heap object. All registers are clobbered also when control
+  // continues at the gc_required label.
   void AllocateInNewSpace(int object_size,
                           Register result,
                           Register scratch1,
@@ -512,16 +562,6 @@
   }
 
 
-  inline void BranchOnSmi(Register value, Label* smi_label) {
-    tst(value, Operand(kSmiTagMask));
-    b(eq, smi_label);
-  }
-
-  inline void BranchOnNotSmi(Register value, Label* not_smi_label) {
-    tst(value, Operand(kSmiTagMask));
-    b(ne, not_smi_label);
-  }
-
   // Generates code for reporting that an illegal operation has
   // occurred.
   void IllegalOperation(int num_arguments);
@@ -534,6 +574,7 @@
 
   // Get the number of least significant bits from a register
   void GetLeastBitsFromSmi(Register dst, Register src, int num_least_bits);
+  void GetLeastBitsFromInt32(Register dst, Register src, int mun_least_bits);
 
   // Uses VFP instructions to Convert a Smi to a double.
   void IntegerToDoubleConversionWithVFP3(Register inReg,
@@ -563,11 +604,13 @@
 
   // Convert the HeapNumber pointed to by source to a 32bits signed integer
   // dest. If the HeapNumber does not fit into a 32bits signed integer branch
-  // to not_int32 label.
+  // to not_int32 label. If VFP3 is available double_scratch is used but not
+  // scratch2.
   void ConvertToInt32(Register source,
                       Register dest,
                       Register scratch,
                       Register scratch2,
+                      DwVfpRegister double_scratch,
                       Label *not_int32);
 
   // Count leading zeros in a 32 bit word.  On ARM5 and later it uses the clz
@@ -588,6 +631,12 @@
   // Call a code stub.
   void TailCallStub(CodeStub* stub, Condition cond = al);
 
+  // Tail call a code stub (jump) and return the code object called.  Try to
+  // generate the code if necessary.  Do not perform a GC but instead return
+  // a retry after GC failure.
+  MUST_USE_RESULT MaybeObject* TryTailCallStub(CodeStub* stub,
+                                               Condition cond = al);
+
   // Call a runtime routine.
   void CallRuntime(Runtime::Function* f, int num_arguments);
   void CallRuntimeSaveDoubles(Runtime::FunctionId id);
@@ -606,6 +655,12 @@
                                  int num_arguments,
                                  int result_size);
 
+  // Tail call of a runtime routine (jump). Try to generate the code if
+  // necessary. Do not perform a GC but instead return a retry after GC
+  // failure.
+  MUST_USE_RESULT MaybeObject* TryTailCallExternalReference(
+      const ExternalReference& ext, int num_arguments, int result_size);
+
   // Convenience function: tail call a runtime routine (jump).
   void TailCallRuntime(Runtime::FunctionId fid,
                        int num_arguments,
@@ -629,12 +684,23 @@
   void CallCFunction(ExternalReference function, int num_arguments);
   void CallCFunction(Register function, int num_arguments);
 
+  // Calls an API function. Allocates HandleScope, extracts returned value
+  // from handle and propagates exceptions. Restores context.
+  // stack_space - space to be unwound on exit (includes the call js
+  // arguments space and the additional space allocated for the fast call).
+  MaybeObject* TryCallApiFunctionAndReturn(ApiFunction* function,
+                                           int stack_space);
+
   // Jump to a runtime routine.
   void JumpToExternalReference(const ExternalReference& builtin);
 
+  MaybeObject* TryJumpToExternalReference(const ExternalReference& ext);
+
   // Invoke specified builtin JavaScript function. Adds an entry to
   // the unresolved list if the name does not resolve.
-  void InvokeBuiltin(Builtins::JavaScript id, InvokeJSFlags flags);
+  void InvokeBuiltin(Builtins::JavaScript id,
+                     InvokeJSFlags flags,
+                     PostCallGenerator* post_call_generator = NULL);
 
   // Store the code object for the given builtin in the target register and
   // setup the function in r1.
@@ -660,14 +726,14 @@
   // ---------------------------------------------------------------------------
   // Debugging
 
-  // Calls Abort(msg) if the condition cc is not satisfied.
+  // Calls Abort(msg) if the condition cond is not satisfied.
   // Use --debug_code to enable.
-  void Assert(Condition cc, const char* msg);
+  void Assert(Condition cond, const char* msg);
   void AssertRegisterIsRoot(Register reg, Heap::RootListIndex index);
   void AssertFastElements(Register elements);
 
   // Like Assert(), but always enabled.
-  void Check(Condition cc, const char* msg);
+  void Check(Condition cond, const char* msg);
 
   // Print a message to stdout and abort execution.
   void Abort(const char* msg);
@@ -679,25 +745,79 @@
   bool allow_stub_calls() { return allow_stub_calls_; }
 
   // ---------------------------------------------------------------------------
+  // Number utilities
+
+  // Check whether the value of reg is a power of two and not zero. If not
+  // control continues at the label not_power_of_two. If reg is a power of two
+  // the register scratch contains the value of (reg - 1) when control falls
+  // through.
+  void JumpIfNotPowerOfTwoOrZero(Register reg,
+                                 Register scratch,
+                                 Label* not_power_of_two_or_zero);
+
+  // ---------------------------------------------------------------------------
   // Smi utilities
 
   void SmiTag(Register reg, SBit s = LeaveCC) {
     add(reg, reg, Operand(reg), s);
   }
+  void SmiTag(Register dst, Register src, SBit s = LeaveCC) {
+    add(dst, src, Operand(src), s);
+  }
 
+  // Try to convert int32 to smi. If the value is to large, preserve
+  // the original value and jump to not_a_smi. Destroys scratch and
+  // sets flags.
+  void TrySmiTag(Register reg, Label* not_a_smi, Register scratch) {
+    mov(scratch, reg);
+    SmiTag(scratch, SetCC);
+    b(vs, not_a_smi);
+    mov(reg, scratch);
+  }
+
   void SmiUntag(Register reg) {
     mov(reg, Operand(reg, ASR, kSmiTagSize));
   }
+  void SmiUntag(Register dst, Register src) {
+    mov(dst, Operand(src, ASR, kSmiTagSize));
+  }
 
+  // Jump the register contains a smi.
+  inline void JumpIfSmi(Register value, Label* smi_label) {
+    tst(value, Operand(kSmiTagMask));
+    b(eq, smi_label);
+  }
   // Jump if either of the registers contain a non-smi.
+  inline void JumpIfNotSmi(Register value, Label* not_smi_label) {
+    tst(value, Operand(kSmiTagMask));
+    b(ne, not_smi_label);
+  }
+  // Jump if either of the registers contain a non-smi.
   void JumpIfNotBothSmi(Register reg1, Register reg2, Label* on_not_both_smi);
   // Jump if either of the registers contain a smi.
   void JumpIfEitherSmi(Register reg1, Register reg2, Label* on_either_smi);
 
   // Abort execution if argument is a smi. Used in debug code.
   void AbortIfSmi(Register object);
+  void AbortIfNotSmi(Register object);
 
+  // Abort execution if argument is a string. Used in debug code.
+  void AbortIfNotString(Register object);
+
+  // Abort execution if argument is not the root value with the given index.
+  void AbortIfNotRootValue(Register src,
+                           Heap::RootListIndex root_value_index,
+                           const char* message);
+
   // ---------------------------------------------------------------------------
+  // HeapNumber utilities
+
+  void JumpIfNotHeapNumber(Register object,
+                           Register heap_number_map,
+                           Register scratch,
+                           Label* on_not_heap_number);
+
+  // ---------------------------------------------------------------------------
   // String utilities
 
   // Checks if both objects are sequential ASCII strings and jumps to label
@@ -732,6 +852,15 @@
                                               Label* failure);
 
 
+  // ---------------------------------------------------------------------------
+  // Patching helpers.
+
+  // Get the location of a relocated constant (its address in the constant pool)
+  // from its load site.
+  void GetRelocatedValueLocation(Register ldr_location,
+                                 Register result);
+
+
  private:
   void Jump(intptr_t target, RelocInfo::Mode rmode, Condition cond = al);
   void Call(intptr_t target, RelocInfo::Mode rmode, Condition cond = al);
@@ -742,7 +871,8 @@
                       Handle<Code> code_constant,
                       Register code_reg,
                       Label* done,
-                      InvokeFlag flag);
+                      InvokeFlag flag,
+                      PostCallGenerator* post_call_generator = NULL);
 
   // Activation support.
   void EnterFrame(StackFrame::Type type);
@@ -776,11 +906,15 @@
   MacroAssembler* masm() { return &masm_; }
 
   // Emit an instruction directly.
-  void Emit(Instr x);
+  void Emit(Instr instr);
 
   // Emit an address directly.
   void Emit(Address addr);
 
+  // Emit the condition part of an instruction leaving the rest of the current
+  // instruction unchanged.
+  void EmitCondition(Condition cond);
+
  private:
   byte* address_;  // The address of the code being patched.
   int instructions_;  // Number of instructions of the expected patch size.