Porting r9456 to arm (Optimize KeyedStoreGeneric for Smi arrays).

Review URL: http://codereview.chromium.org/8065004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9531 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/arm/ic-arm.cc

@@ -1272,13 +1272,17 @@ void KeyedStoreIC::GenerateGeneric(MacroAssembler* masm,
   //  -- r2     : receiver
   //  -- lr     : return address
   // -----------------------------------
-  Label slow, fast, array, extra;
+  Label slow, array, extra, check_if_double_array;
+  Label fast_object_with_map_check, fast_object_without_map_check;
+  Label fast_double_with_map_check, fast_double_without_map_check;
 
   // Register usage.
   Register value = r0;
   Register key = r1;
   Register receiver = r2;
   Register elements = r3;  // Elements array of the receiver.
+  Register elements_map = r6;
+  Register receiver_map = r7;
   // r4 and r5 are used as general scratch registers.
 
   // Check that the key is a smi.
@@ -1286,14 +1290,14 @@ void KeyedStoreIC::GenerateGeneric(MacroAssembler* masm,
   // Check that the object isn't a smi.
   __ JumpIfSmi(receiver, &slow);
   // Get the map of the object.
-  __ ldr(r4, FieldMemOperand(receiver, HeapObject::kMapOffset));
+  __ ldr(receiver_map, FieldMemOperand(receiver, HeapObject::kMapOffset));
   // Check that the receiver does not require access checks.  We need
   // to do this because this generic stub does not perform map checks.
-  __ ldrb(ip, FieldMemOperand(r4, Map::kBitFieldOffset));
+  __ ldrb(ip, FieldMemOperand(receiver_map, Map::kBitFieldOffset));
   __ tst(ip, Operand(1 << Map::kIsAccessCheckNeeded));
   __ b(ne, &slow);
   // Check if the object is a JS array or not.
-  __ ldrb(r4, FieldMemOperand(r4, Map::kInstanceTypeOffset));
+  __ ldrb(r4, FieldMemOperand(receiver_map, Map::kInstanceTypeOffset));
   __ cmp(r4, Operand(JS_ARRAY_TYPE));
   __ b(eq, &array);
   // Check that the object is some kind of JSObject.
@@ -1302,15 +1306,10 @@ void KeyedStoreIC::GenerateGeneric(MacroAssembler* masm,
 
   // Object case: Check key against length in the elements array.
   __ ldr(elements, FieldMemOperand(receiver, JSObject::kElementsOffset));
-  // Check that the object is in fast mode and writable.
-  __ ldr(r4, FieldMemOperand(elements, HeapObject::kMapOffset));
-  __ LoadRoot(ip, Heap::kFixedArrayMapRootIndex);
-  __ cmp(r4, ip);
-  __ b(ne, &slow);
   // Check array bounds. Both the key and the length of FixedArray are smis.
   __ ldr(ip, FieldMemOperand(elements, FixedArray::kLengthOffset));
   __ cmp(key, Operand(ip));
-  __ b(lo, &fast);
+  __ b(lo, &fast_object_with_map_check);
 
   // Slow case, handle jump to runtime.
   __ bind(&slow);
@@ -1331,21 +1330,31 @@ void KeyedStoreIC::GenerateGeneric(MacroAssembler* masm,
   __ ldr(ip, FieldMemOperand(elements, FixedArray::kLengthOffset));
   __ cmp(key, Operand(ip));
   __ b(hs, &slow);
+  __ ldr(elements_map, FieldMemOperand(elements, HeapObject::kMapOffset));
+  __ cmp(elements_map,
+         Operand(masm->isolate()->factory()->fixed_array_map()));
+  __ b(ne, &check_if_double_array);
   // Calculate key + 1 as smi.
   STATIC_ASSERT(kSmiTag == 0);
   __ add(r4, key, Operand(Smi::FromInt(1)));
   __ str(r4, FieldMemOperand(receiver, JSArray::kLengthOffset));
-  __ b(&fast);
+  __ b(&fast_object_without_map_check);
+
+  __ bind(&check_if_double_array);
+  __ cmp(elements_map,
+         Operand(masm->isolate()->factory()->fixed_double_array_map()));
+  __ b(ne, &slow);
+  // Add 1 to key, and go to common element store code for doubles.
+  STATIC_ASSERT(kSmiTag == 0);
+  __ add(r4, key, Operand(Smi::FromInt(1)));
+  __ str(r4, FieldMemOperand(receiver, JSArray::kLengthOffset));
+  __ jmp(&fast_double_without_map_check);
 
   // Array case: Get the length and the elements array from the JS
   // array. Check that the array is in fast mode (and writable); if it
   // is the length is always a smi.
   __ bind(&array);
   __ ldr(elements, FieldMemOperand(receiver, JSObject::kElementsOffset));
-  __ ldr(r4, FieldMemOperand(elements, HeapObject::kMapOffset));
-  __ LoadRoot(ip, Heap::kFixedArrayMapRootIndex);
-  __ cmp(r4, ip);
-  __ b(ne, &slow);
 
   // Check the key against the length in the array.
   __ ldr(ip, FieldMemOperand(receiver, JSArray::kLengthOffset));
@@ -1353,10 +1362,15 @@ void KeyedStoreIC::GenerateGeneric(MacroAssembler* masm,
   __ b(hs, &extra);
   // Fall through to fast case.
 
-  __ bind(&fast);
+  __ bind(&fast_object_with_map_check);
   Register scratch_value = r4;
   Register address = r5;
-
+  __ ldr(elements_map, FieldMemOperand(elements, HeapObject::kMapOffset));
+  __ cmp(elements_map,
+         Operand(masm->isolate()->factory()->fixed_array_map()));
+  __ b(ne, &fast_double_with_map_check);
+  __ bind(&fast_object_without_map_check);
+  // Smi stores don't require further checks.
   Label non_smi_value;
   __ JumpIfNotSmi(value, &non_smi_value);
   // It's irrelevant whether array is smi-only or not when writing a smi.
@@ -1368,8 +1382,7 @@ void KeyedStoreIC::GenerateGeneric(MacroAssembler* masm,
   __ bind(&non_smi_value);
   if (FLAG_smi_only_arrays) {
     // Escape to slow case when writing non-smi into smi-only array.
-    __ ldr(scratch_value, FieldMemOperand(receiver, HeapObject::kMapOffset));
-    __ CheckFastObjectElements(scratch_value, scratch_value, &slow);
+    __ CheckFastObjectElements(receiver_map, scratch_value, &slow);
   }
   // Fast elements array, store the value to the elements backing store.
   __ add(address, elements, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
@@ -1385,6 +1398,24 @@ void KeyedStoreIC::GenerateGeneric(MacroAssembler* masm,
                  EMIT_REMEMBERED_SET,
                  OMIT_SMI_CHECK);
   __ Ret();
+
+  __ bind(&fast_double_with_map_check);
+  // Check for fast double array case. If this fails, call through to the
+  // runtime.
+  __ cmp(elements_map,
+         Operand(masm->isolate()->factory()->fixed_double_array_map()));
+  __ b(ne, &slow);
+  __ bind(&fast_double_without_map_check);
+  __ StoreNumberToDoubleElements(value,
+                                 key,
+                                 receiver,
+                                 elements,
+                                 r4,
+                                 r5,
+                                 r6,
+                                 r7,
+                                 &slow);
+  __ Ret();
 }
 
 

src/arm/macro-assembler-arm.cc

@@ -1890,6 +1890,96 @@ void MacroAssembler::CheckFastSmiOnlyElements(Register map,
 }
 
 
+void MacroAssembler::StoreNumberToDoubleElements(Register value_reg,
+                                                 Register key_reg,
+                                                 Register receiver_reg,
+                                                 Register elements_reg,
+                                                 Register scratch1,
+                                                 Register scratch2,
+                                                 Register scratch3,
+                                                 Register scratch4,
+                                                 Label* fail) {
+  Label smi_value, maybe_nan, have_double_value, is_nan, done;
+  Register mantissa_reg = scratch2;
+  Register exponent_reg = scratch3;
+
+  // Handle smi values specially.
+  JumpIfSmi(value_reg, &smi_value);
+
+  // Ensure that the object is a heap number
+  CheckMap(value_reg,
+           scratch1,
+           isolate()->factory()->heap_number_map(),
+           fail,
+           DONT_DO_SMI_CHECK);
+
+  // Check for nan: all NaN values have a value greater (signed) than 0x7ff00000
+  // in the exponent.
+  mov(scratch1, Operand(kNaNOrInfinityLowerBoundUpper32));
+  ldr(exponent_reg, FieldMemOperand(value_reg, HeapNumber::kExponentOffset));
+  cmp(exponent_reg, scratch1);
+  b(ge, &maybe_nan);
+
+  ldr(mantissa_reg, FieldMemOperand(value_reg, HeapNumber::kMantissaOffset));
+
+  bind(&have_double_value);
+  add(scratch1, elements_reg,
+      Operand(key_reg, LSL, kDoubleSizeLog2 - kSmiTagSize));
+  str(mantissa_reg, FieldMemOperand(scratch1, FixedDoubleArray::kHeaderSize));
+  uint32_t offset = FixedDoubleArray::kHeaderSize + sizeof(kHoleNanLower32);
+  str(exponent_reg, FieldMemOperand(scratch1, offset));
+  jmp(&done);
+
+  bind(&maybe_nan);
+  // Could be NaN or Infinity. If fraction is not zero, it's NaN, otherwise
+  // it's an Infinity, and the non-NaN code path applies.
+  b(gt, &is_nan);
+  ldr(mantissa_reg, FieldMemOperand(value_reg, HeapNumber::kMantissaOffset));
+  cmp(mantissa_reg, Operand(0));
+  b(eq, &have_double_value);
+  bind(&is_nan);
+  // Load canonical NaN for storing into the double array.
+  uint64_t nan_int64 = BitCast<uint64_t>(
+      FixedDoubleArray::canonical_not_the_hole_nan_as_double());
+  mov(mantissa_reg, Operand(static_cast<uint32_t>(nan_int64)));
+  mov(exponent_reg, Operand(static_cast<uint32_t>(nan_int64 >> 32)));
+  jmp(&have_double_value);
+
+  bind(&smi_value);
+  add(scratch1, elements_reg,
+      Operand(FixedDoubleArray::kHeaderSize - kHeapObjectTag));
+  add(scratch1, scratch1,
+      Operand(key_reg, LSL, kDoubleSizeLog2 - kSmiTagSize));
+  // scratch1 is now effective address of the double element
+
+  FloatingPointHelper::Destination destination;
+  if (CpuFeatures::IsSupported(VFP3)) {
+    destination = FloatingPointHelper::kVFPRegisters;
+  } else {
+    destination = FloatingPointHelper::kCoreRegisters;
+  }
+
+  Register untagged_value = receiver_reg;
+  SmiUntag(untagged_value, value_reg);
+  FloatingPointHelper::ConvertIntToDouble(this,
+                                          untagged_value,
+                                          destination,
+                                          d0,
+                                          mantissa_reg,
+                                          exponent_reg,
+                                          scratch4,
+                                          s2);
+  if (destination == FloatingPointHelper::kVFPRegisters) {
+    CpuFeatures::Scope scope(VFP3);
+    vstr(d0, scratch1, 0);
+  } else {
+    str(mantissa_reg, MemOperand(scratch1, 0));
+    str(exponent_reg, MemOperand(scratch1, Register::kSizeInBytes));
+  }
+  bind(&done);
+}
+
+
 void MacroAssembler::CheckMap(Register obj,
                               Register scratch,
                               Handle<Map> map,

src/arm/macro-assembler-arm.h

@@ -712,6 +712,19 @@ class MacroAssembler: public Assembler {
                                 Register scratch,
                                 Label* fail);
 
+  // Check to see if maybe_number can be stored as a double in
+  // FastDoubleElements. If it can, store it at the index specified by key in
+  // the FastDoubleElements array elements, otherwise jump to fail.
+  void StoreNumberToDoubleElements(Register value_reg,
+                                   Register key_reg,
+                                   Register receiver_reg,
+                                   Register elements_reg,
+                                   Register scratch1,
+                                   Register scratch2,
+                                   Register scratch3,
+                                   Register scratch4,
+                                   Label* fail);
+
   // Check if the map of an object is equal to a specified map (either
   // given directly or as an index into the root list) and branch to
   // label if not. Skip the smi check if not required (object is known

src/arm/stub-cache-arm.cc

@@ -4400,15 +4400,15 @@ void KeyedStoreStubCompiler::GenerateStoreFastDoubleElement(
   //  -- r4    : scratch
   //  -- r5    : scratch
   // -----------------------------------
-  Label miss_force_generic, smi_value, is_nan, maybe_nan, have_double_value;
+  Label miss_force_generic;
 
   Register value_reg = r0;
   Register key_reg = r1;
   Register receiver_reg = r2;
-  Register scratch = r3;
-  Register elements_reg = r4;
-  Register mantissa_reg = r5;
-  Register exponent_reg = r6;
+  Register elements_reg = r3;
+  Register scratch1 = r4;
+  Register scratch2 = r5;
+  Register scratch3 = r6;
   Register scratch4 = r7;
 
   // This stub is meant to be tail-jumped to, the receiver must already
@@ -4420,90 +4420,25 @@ void KeyedStoreStubCompiler::GenerateStoreFastDoubleElement(
 
   // Check that the key is within bounds.
   if (is_js_array) {
-    __ ldr(scratch, FieldMemOperand(receiver_reg, JSArray::kLengthOffset));
+    __ ldr(scratch1, FieldMemOperand(receiver_reg, JSArray::kLengthOffset));
   } else {
-    __ ldr(scratch,
+    __ ldr(scratch1,
            FieldMemOperand(elements_reg, FixedArray::kLengthOffset));
   }
   // Compare smis, unsigned compare catches both negative and out-of-bound
   // indexes.
-  __ cmp(key_reg, scratch);
+  __ cmp(key_reg, scratch1);
   __ b(hs, &miss_force_generic);
 
-  // Handle smi values specially.
-  __ JumpIfSmi(value_reg, &smi_value);
-
-  // Ensure that the object is a heap number
-  __ CheckMap(value_reg,
-              scratch,
-              masm->isolate()->factory()->heap_number_map(),
-              &miss_force_generic,
-              DONT_DO_SMI_CHECK);
-
-  // Check for nan: all NaN values have a value greater (signed) than 0x7ff00000
-  // in the exponent.
-  __ mov(scratch, Operand(kNaNOrInfinityLowerBoundUpper32));
-  __ ldr(exponent_reg, FieldMemOperand(value_reg, HeapNumber::kExponentOffset));
-  __ cmp(exponent_reg, scratch);
-  __ b(ge, &maybe_nan);
-
-  __ ldr(mantissa_reg, FieldMemOperand(value_reg, HeapNumber::kMantissaOffset));
-
-  __ bind(&have_double_value);
-  __ add(scratch, elements_reg,
-         Operand(key_reg, LSL, kDoubleSizeLog2 - kSmiTagSize));
-  __ str(mantissa_reg, FieldMemOperand(scratch, FixedDoubleArray::kHeaderSize));
-  uint32_t offset = FixedDoubleArray::kHeaderSize + sizeof(kHoleNanLower32);
-  __ str(exponent_reg, FieldMemOperand(scratch, offset));
-  __ Ret();
-
-  __ bind(&maybe_nan);
-  // Could be NaN or Infinity. If fraction is not zero, it's NaN, otherwise
-  // it's an Infinity, and the non-NaN code path applies.
-  __ b(gt, &is_nan);
-  __ ldr(mantissa_reg, FieldMemOperand(value_reg, HeapNumber::kMantissaOffset));
-  __ cmp(mantissa_reg, Operand(0));
-  __ b(eq, &have_double_value);
-  __ bind(&is_nan);
-  // Load canonical NaN for storing into the double array.
-  uint64_t nan_int64 = BitCast<uint64_t>(
-      FixedDoubleArray::canonical_not_the_hole_nan_as_double());
-  __ mov(mantissa_reg, Operand(static_cast<uint32_t>(nan_int64)));
-  __ mov(exponent_reg, Operand(static_cast<uint32_t>(nan_int64 >> 32)));
-  __ jmp(&have_double_value);
-
-  __ bind(&smi_value);
-  __ add(scratch, elements_reg,
-         Operand(FixedDoubleArray::kHeaderSize - kHeapObjectTag));
-  __ add(scratch, scratch,
-         Operand(key_reg, LSL, kDoubleSizeLog2 - kSmiTagSize));
-  // scratch is now effective address of the double element
-
-  FloatingPointHelper::Destination destination;
-  if (CpuFeatures::IsSupported(VFP3)) {
-    destination = FloatingPointHelper::kVFPRegisters;
-  } else {
-    destination = FloatingPointHelper::kCoreRegisters;
-  }
-
-  Register untagged_value = receiver_reg;
-  __ SmiUntag(untagged_value, value_reg);
-  FloatingPointHelper::ConvertIntToDouble(
-      masm,
-      untagged_value,
-      destination,
-      d0,
-      mantissa_reg,
-      exponent_reg,
-      scratch4,
-      s2);
-  if (destination == FloatingPointHelper::kVFPRegisters) {
-    CpuFeatures::Scope scope(VFP3);
-    __ vstr(d0, scratch, 0);
-  } else {
-    __ str(mantissa_reg, MemOperand(scratch, 0));
-    __ str(exponent_reg, MemOperand(scratch, Register::kSizeInBytes));
-  }
+  __ StoreNumberToDoubleElements(value_reg,
+                                 key_reg,
+                                 receiver_reg,
+                                 elements_reg,
+                                 scratch1,
+                                 scratch2,
+                                 scratch3,
+                                 scratch4,
+                                 &miss_force_generic);
   __ Ret();
 
   // Handle store cache miss, replacing the ic with the generic stub.