Adds intrinsics for arm64.

runtime/vm/intrinsifier_arm64.cc

Index: runtime/vm/intrinsifier_arm64.cc
===================================================================
--- runtime/vm/intrinsifier_arm64.cc	(revision 36300)
+++ runtime/vm/intrinsifier_arm64.cc	(working copy)
@@ -15,60 +15,260 @@
 
 namespace dart {
 
+DECLARE_FLAG(bool, enable_type_checks);
+
 #define __ assembler->
 
 
 void Intrinsifier::Array_getLength(Assembler* assembler) {
-  return;
+  __ ldr(R0, Address(SP, 0 * kWordSize));
+  __ ldr(R0, FieldAddress(R0, Array::length_offset()));
+  __ ret();
 }
 
 
 void Intrinsifier::ImmutableList_getLength(Assembler* assembler) {
-  return;
+  Array_getLength(assembler);
 }
 
 
 void Intrinsifier::Array_getIndexed(Assembler* assembler) {
-  return;
+  Label fall_through;
+
+  __ ldr(R0, Address(SP, + 0 * kWordSize));  // Index
+  __ ldr(R1, Address(SP, + 1 * kWordSize));  // Array
+
+  __ tsti(R0, kSmiTagMask);
+  __ b(&fall_through, NE);  // Index is not an smi, fall through.
+
+  // range check
+  __ ldr(R6, FieldAddress(R1, Array::length_offset()));
+  __ cmp(R0, Operand(R6));
+  __ b(&fall_through, CS);
+
+  ASSERT(kSmiTagShift == 1);
+  // array element at R1 + R0*4 + Array::data_offset - 1
+  __ add(R6, R1, Operand(R0, LSL, 2));
+  __ ldr(R0, FieldAddress(R6, Array::data_offset()));
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::ImmutableList_getIndexed(Assembler* assembler) {
-  return;
+  Array_getIndexed(assembler);
 }
 
 
+static intptr_t ComputeObjectArrayTypeArgumentsOffset() {
+  const Library& core_lib = Library::Handle(Library::CoreLibrary());
+  const Class& cls = Class::Handle(
+      core_lib.LookupClassAllowPrivate(Symbols::_List()));
+  ASSERT(!cls.IsNull());
+  ASSERT(cls.NumTypeArguments() == 1);
+  const intptr_t field_offset = cls.type_arguments_field_offset();
+  ASSERT(field_offset != Class::kNoTypeArguments);
+  return field_offset;
+}
+
+
+// Intrinsify only for Smi value and index. Non-smi values need a store buffer
+// update. Array length is always a Smi.
 void Intrinsifier::Array_setIndexed(Assembler* assembler) {
-  return;
+  Label fall_through;
+
+  if (FLAG_enable_type_checks) {
+    const intptr_t type_args_field_offset =
+        ComputeObjectArrayTypeArgumentsOffset();
+    // Inline simple tests (Smi, null), fallthrough if not positive.
+    Label checked_ok;
+    __ ldr(R2, Address(SP, 0 * kWordSize));  // Value.
+
+    // Null value is valid for any type.
+    __ CompareObject(R2, Object::null_object(), PP);
+    __ b(&checked_ok, EQ);
+
+    __ ldr(R1, Address(SP, 2 * kWordSize));  // Array.
+    __ ldr(R1, FieldAddress(R1, type_args_field_offset));
+
+    // R1: Type arguments of array.
+    __ CompareObject(R1, Object::null_object(), PP);
+    __ b(&checked_ok, EQ);
+
+    // Check if it's dynamic.
+    // Get type at index 0.
+    __ ldr(R0, FieldAddress(R1, TypeArguments::type_at_offset(0)));
+    __ CompareObject(R0, Type::ZoneHandle(Type::DynamicType()), PP);
+    __ b(&checked_ok, EQ);
+
+    // Check for int and num.
+    __ tsti(R2, kSmiTagMask);  // Value is Smi?
+    __ b(&fall_through, NE);  // Non-smi value.
+    __ CompareObject(R0, Type::ZoneHandle(Type::IntType()), PP);
+    __ b(&checked_ok, EQ);
+    __ CompareObject(R0, Type::ZoneHandle(Type::Number()), PP);
+    __ b(&fall_through, NE);
+    __ Bind(&checked_ok);
+  }
+  __ ldr(R1, Address(SP, 1 * kWordSize));  // Index.
+  __ tsti(R1, kSmiTagMask);
+  // Index not Smi.
+  __ b(&fall_through, NE);
+  __ ldr(R0, Address(SP, 2 * kWordSize));  // Array.
+
+  // Range check.
+  __ ldr(R3, FieldAddress(R0, Array::length_offset()));  // Array length.
+  __ cmp(R1, Operand(R3));
+  // Runtime throws exception.
+  __ b(&fall_through, CS);
+
+  // Note that R1 is Smi, i.e, times 2.
+  ASSERT(kSmiTagShift == 1);
+  __ ldr(R2, Address(SP, 0 * kWordSize));  // Value.
+  __ add(R1, R0, Operand(R1, LSL, 2));  // R1 is Smi.
+  __ StoreIntoObject(R0,
+                     FieldAddress(R1, Array::data_offset()),
+                     R2);
+  // Caller is responsible for preserving the value if necessary.
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
 // Allocate a GrowableObjectArray using the backing array specified.
 // On stack: type argument (+1), data (+0).
 void Intrinsifier::GrowableList_Allocate(Assembler* assembler) {
-  return;
+  // The newly allocated object is returned in R0.
+  const intptr_t kTypeArgumentsOffset = 1 * kWordSize;
+  const intptr_t kArrayOffset = 0 * kWordSize;
+  Label fall_through;
+
+  // Compute the size to be allocated, it is based on the array length
+  // and is computed as:
+  // RoundedAllocationSize(sizeof(RawGrowableObjectArray)) +
+  intptr_t fixed_size = GrowableObjectArray::InstanceSize();
+
+  Isolate* isolate = Isolate::Current();
+  Heap* heap = isolate->heap();
+
+  __ LoadImmediate(R2, heap->TopAddress(), kNoPP);
+  __ ldr(R0, Address(R2, 0));
+  __ AddImmediate(R1, R0, fixed_size, kNoPP);
+
+  // Check if the allocation fits into the remaining space.
+  // R0: potential new backing array object start.
+  // R1: potential next object start.
+  __ LoadImmediate(R3, heap->EndAddress(), kNoPP);
+  __ ldr(R3, Address(R3, 0));
+  __ cmp(R1, Operand(R3));
+  __ b(&fall_through, CS);
+
+  // Successfully allocated the object(s), now update top to point to
+  // next object start and initialize the object.
+  __ str(R1, Address(R2, 0));
+  __ AddImmediate(R0, R0, kHeapObjectTag, kNoPP);
+
+  // Initialize the tags.
+  // R0: new growable array object start as a tagged pointer.
+  const Class& cls = Class::Handle(
+      isolate->object_store()->growable_object_array_class());
+  uword tags = 0;
+  tags = RawObject::SizeTag::update(fixed_size, tags);
+  tags = RawObject::ClassIdTag::update(cls.id(), tags);
+  __ LoadImmediate(R1, tags, kNoPP);
+  __ str(R1, FieldAddress(R0, GrowableObjectArray::tags_offset()));
+
+  // Store backing array object in growable array object.
+  __ ldr(R1, Address(SP, kArrayOffset));  // Data argument.
+  // R0 is new, no barrier needed.
+  __ StoreIntoObjectNoBarrier(
+      R0,
+      FieldAddress(R0, GrowableObjectArray::data_offset()),
+      R1);
+
+  // R0: new growable array object start as a tagged pointer.
+  // Store the type argument field in the growable array object.
+  __ ldr(R1, Address(SP, kTypeArgumentsOffset));  // Type argument.
+  __ StoreIntoObjectNoBarrier(
+      R0,
+      FieldAddress(R0, GrowableObjectArray::type_arguments_offset()),
+      R1);
+
+  // Set the length field in the growable array object to 0.
+  __ LoadImmediate(R1, 0, kNoPP);
+  __ str(R1, FieldAddress(R0, GrowableObjectArray::length_offset()));
+  __ UpdateAllocationStats(kGrowableObjectArrayCid, R1, kNoPP);
+  __ ret();  // Returns the newly allocated object in R0.
+
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::GrowableList_getLength(Assembler* assembler) {
-  return;
+  __ ldr(R0, Address(SP, 0 * kWordSize));
+  __ ldr(R0, FieldAddress(R0, GrowableObjectArray::length_offset()));
+  __ ret();
 }
 
 
 void Intrinsifier::GrowableList_getCapacity(Assembler* assembler) {
-  return;
+  __ ldr(R0, Address(SP, 0 * kWordSize));
+  __ ldr(R0, FieldAddress(R0, GrowableObjectArray::data_offset()));
+  __ ldr(R0, FieldAddress(R0, Array::length_offset()));
+  __ ret();
 }
 
 
 void Intrinsifier::GrowableList_getIndexed(Assembler* assembler) {
-  return;
+  Label fall_through;
+
+  __ ldr(R0, Address(SP, + 0 * kWordSize));  // Index
+  __ ldr(R1, Address(SP, + 1 * kWordSize));  // Array
+
+  __ tsti(R0, kSmiTagMask);
+  __ b(&fall_through, NE);  // Index is not an smi, fall through.
+
+  // range check
+  __ ldr(R6, FieldAddress(R1, GrowableObjectArray::length_offset()));
+  __ cmp(R0, Operand(R6));
+  __ b(&fall_through, CS);
+
+  ASSERT(kSmiTagShift == 1);
+  // array element at R6 + R0 * 4 + Array::data_offset - 1
+  __ ldr(R6, FieldAddress(R1, GrowableObjectArray::data_offset()));  // Data
+  __ add(R6, R6, Operand(R0, LSL, 2));
+  __ ldr(R0, FieldAddress(R6, Array::data_offset()));
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
 // Set value into growable object array at specified index.
 // On stack: growable array (+2), index (+1), value (+0).
 void Intrinsifier::GrowableList_setIndexed(Assembler* assembler) {
-  return;
+  if (FLAG_enable_type_checks) {
+    return;
+  }
+  Label fall_through;
+  __ ldr(R1, Address(SP, 1 * kWordSize));  // Index.
+  __ ldr(R0, Address(SP, 2 * kWordSize));  // GrowableArray.
+  __ tsti(R1, kSmiTagMask);
+  __ b(&fall_through, NE);  // Non-smi index.
+  // Range check using _length field.
+  __ ldr(R2, FieldAddress(R0, GrowableObjectArray::length_offset()));
+  __ cmp(R1, Operand(R2));
+  // Runtime throws exception.
+  __ b(&fall_through, CS);
+  __ ldr(R0, FieldAddress(R0, GrowableObjectArray::data_offset()));  // data.
+  __ ldr(R2, Address(SP, 0 * kWordSize));  // Value.
+  // Note that R1 is Smi, i.e, times 2.
+  ASSERT(kSmiTagShift == 1);
+  __ add(R1, R0, Operand(R1, LSL, 2));
+  __ StoreIntoObject(R0,
+                     FieldAddress(R1, Array::data_offset()),
+                     R2);
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
@@ -76,69 +276,315 @@
 // be greater than the length of the data container.
 // On stack: growable array (+1), length (+0).
 void Intrinsifier::GrowableList_setLength(Assembler* assembler) {
-  return;
+  Label fall_through;
+  __ ldr(R0, Address(SP, 1 * kWordSize));  // Growable array.
+  __ ldr(R1, Address(SP, 0 * kWordSize));  // Length value.
+  __ tsti(R1, kSmiTagMask);  // Check for Smi.
+  __ b(&fall_through, NE);
+  __ str(R1, FieldAddress(R0, GrowableObjectArray::length_offset()));
+  __ ret();
+  __ Bind(&fall_through);
+  // Fall through on non-Smi.
 }
 
 
 // Set data of growable object array.
 // On stack: growable array (+1), data (+0).
 void Intrinsifier::GrowableList_setData(Assembler* assembler) {
-  return;
+  if (FLAG_enable_type_checks) {
+    return;
+  }
+  Label fall_through;
+  __ ldr(R1, Address(SP, 0 * kWordSize));  // Data.
+  // Check that data is an ObjectArray.
+  __ tsti(R1, kSmiTagMask);
+  __ b(&fall_through, EQ);  // Data is Smi.
+  __ CompareClassId(R1, kArrayCid, kNoPP);
+  __ b(&fall_through, NE);
+  __ ldr(R0, Address(SP, 1 * kWordSize));  // Growable array.
+  __ StoreIntoObject(R0,
+                     FieldAddress(R0, GrowableObjectArray::data_offset()),
+                     R1);
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
+// Add an element to growable array if it doesn't need to grow, otherwise
+// call into regular code.
+// On stack: growable array (+1), value (+0).
 void Intrinsifier::GrowableList_add(Assembler* assembler) {
-  return;
+  // In checked mode we need to type-check the incoming argument.
+  if (FLAG_enable_type_checks) {
+    return;
+  }
+  Label fall_through;
+  // R0: Array.
+  __ ldr(R0, Address(SP, 1 * kWordSize));
+  // R1: length.
+  __ ldr(R1, FieldAddress(R0, GrowableObjectArray::length_offset()));
+  // R2: data.
+  __ ldr(R2, FieldAddress(R0, GrowableObjectArray::data_offset()));
+  // R3: capacity.
+  __ ldr(R3, FieldAddress(R2, Array::length_offset()));
+  // Compare length with capacity.
+  __ cmp(R1, Operand(R3));
+  __ b(&fall_through, EQ);  // Must grow data.
+  const int64_t value_one = reinterpret_cast<int64_t>(Smi::New(1));
+  // len = len + 1;
+  __ add(R3, R1, Operand(value_one));
+  __ str(R3, FieldAddress(R0, GrowableObjectArray::length_offset()));
+  __ ldr(R0, Address(SP, 0 * kWordSize));  // Value.
+  ASSERT(kSmiTagShift == 1);
+  __ add(R1, R2, Operand(R1, LSL, 2));
+  __ StoreIntoObject(R2,
+                     FieldAddress(R1, Array::data_offset()),
+                     R0);
+  __ LoadObject(R0, Object::null_object(), PP);
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
 // Gets the length of a TypedData.
 void Intrinsifier::TypedData_getLength(Assembler* assembler) {
-  return;
+  __ ldr(R0, Address(SP, 0 * kWordSize));
+  __ ldr(R0, FieldAddress(R0, TypedData::length_offset()));
+  __ ret();
 }
 
 
+static int GetScaleFactor(intptr_t size) {
+  switch (size) {
+    case 1: return 0;
+    case 2: return 1;
+    case 4: return 2;
+    case 8: return 3;
+    case 16: return 4;
+  }
+  UNREACHABLE();
+  return -1;
+}
+
+
+#define TYPED_ARRAY_ALLOCATION(type_name, cid, max_len, scale_shift)           \
+  Label fall_through;                                                          \
+  const intptr_t kArrayLengthStackOffset = 0 * kWordSize;                      \
+  __ ldr(R2, Address(SP, kArrayLengthStackOffset));  /* Array length. */       \
+  /* Check that length is a positive Smi. */                                   \
+  /* R2: requested array length argument. */                                   \
+  __ tsti(R2, kSmiTagMask);                                                    \
+  __ b(&fall_through, NE);                                                     \
+  __ CompareRegisters(R2, ZR);                                                 \
+  __ b(&fall_through, LT);                                                     \
+  __ SmiUntag(R2);                                                             \
+  /* Check for maximum allowed length. */                                      \
+  /* R2: untagged array length. */                                             \
+  __ CompareImmediate(R2, max_len, kNoPP);                                     \
+  __ b(&fall_through, GT);                                                     \
+  __ Lsl(R2, R2, scale_shift);                                                 \
+  const intptr_t fixed_size = sizeof(Raw##type_name) + kObjectAlignment - 1;   \
+  __ AddImmediate(R2, R2, fixed_size, kNoPP);                                  \
+  __ andi(R2, R2, ~(kObjectAlignment - 1));                                    \
+  Heap* heap = Isolate::Current()->heap();                                     \
+                                                                               \
+  __ LoadImmediate(R0, heap->TopAddress(), kNoPP);                             \
+  __ ldr(R0, Address(R0, 0));                                                  \
+                                                                               \
+  /* R2: allocation size. */                                                   \
+  __ add(R1, R0, Operand(R2));                                                 \
+  __ b(&fall_through, VS);                                                     \
+                                                                               \
+  /* Check if the allocation fits into the remaining space. */                 \
+  /* R0: potential new object start. */                                        \
+  /* R1: potential next object start. */                                       \
+  /* R2: allocation size. */                                                   \
+  __ LoadImmediate(R3, heap->EndAddress(), kNoPP);                             \
+  __ ldr(R3, Address(R3, 0));                                                  \
+  __ cmp(R1, Operand(R3));                                                     \
+  __ b(&fall_through, CS);                                                     \
+                                                                               \
+  /* Successfully allocated the object(s), now update top to point to */       \
+  /* next object start and initialize the object. */                           \
+  __ LoadImmediate(R3, heap->TopAddress(), kNoPP);                             \
+  __ str(R1, Address(R3, 0));                                                  \
+  __ AddImmediate(R0, R0, kHeapObjectTag, kNoPP);                              \
+  __ UpdateAllocationStatsWithSize(cid, R2, R4, kNoPP);                        \
+  /* Initialize the tags. */                                                   \
+  /* R0: new object start as a tagged pointer. */                              \
+  /* R1: new object end address. */                                            \
+  /* R2: allocation size. */                                                   \
+  {                                                                            \
+    __ CompareImmediate(R2, RawObject::SizeTag::kMaxSizeTag, kNoPP);           \
+    __ Lsl(R2, R2, RawObject::kSizeTagPos - kObjectAlignmentLog2);             \
+    __ csel(R2, ZR, R2, HI);                                                   \
+                                                                               \
+    /* Get the class index and insert it into the tags. */                     \
+    __ LoadImmediate(TMP, RawObject::ClassIdTag::encode(cid), kNoPP);          \
+    __ orr(R2, R2, Operand(TMP));                                              \
+    __ str(R2, FieldAddress(R0, type_name::tags_offset()));  /* Tags. */       \
+  }                                                                            \
+  /* Set the length field. */                                                  \
+  /* R0: new object start as a tagged pointer. */                              \
+  /* R1: new object end address. */                                            \
+  __ ldr(R2, Address(SP, kArrayLengthStackOffset));  /* Array length. */       \
+  __ StoreIntoObjectNoBarrier(R0,                                              \
+                              FieldAddress(R0, type_name::length_offset()),    \
+                              R2);                                             \
+  /* Initialize all array elements to 0. */                                    \
+  /* R0: new object start as a tagged pointer. */                              \
+  /* R1: new object end address. */                                            \
+  /* R2: iterator which initially points to the start of the variable */       \
+  /* R3: scratch register. */                                                  \
+  /* data area to be initialized. */                                           \
+  __ mov(R3, ZR);                                                              \
+  __ AddImmediate(R2, R0, sizeof(Raw##type_name) - 1, kNoPP);                  \
+  Label init_loop, done;                                                       \
+  __ Bind(&init_loop);                                                         \
+  __ cmp(R2, Operand(R1));                                                     \
+  __ b(&done, CS);                                                             \
+  __ str(R3, Address(R2, 0));                                                  \
+  __ add(R2, R2, Operand(kWordSize));                                          \
+  __ b(&init_loop);                                                            \
+  __ Bind(&done);                                                              \
+                                                                               \
+  __ ret();                                                                    \
+  __ Bind(&fall_through);                                                      \
+
+
 #define TYPED_DATA_ALLOCATOR(clazz)                                            \
 void Intrinsifier::TypedData_##clazz##_new(Assembler* assembler) {             \
-  return;                                                                      \
+  intptr_t size = TypedData::ElementSizeInBytes(kTypedData##clazz##Cid);       \
+  intptr_t max_len = TypedData::MaxElements(kTypedData##clazz##Cid);           \
+  int shift = GetScaleFactor(size);                                            \
+  TYPED_ARRAY_ALLOCATION(TypedData, kTypedData##clazz##Cid, max_len, shift);   \
 }                                                                              \
 void Intrinsifier::TypedData_##clazz##_factory(Assembler* assembler) {         \
-  return;                                                                      \
+  intptr_t size = TypedData::ElementSizeInBytes(kTypedData##clazz##Cid);       \
+  intptr_t max_len = TypedData::MaxElements(kTypedData##clazz##Cid);           \
+  int shift = GetScaleFactor(size);                                            \
+  TYPED_ARRAY_ALLOCATION(TypedData, kTypedData##clazz##Cid, max_len, shift);   \
 }
 CLASS_LIST_TYPED_DATA(TYPED_DATA_ALLOCATOR)
 #undef TYPED_DATA_ALLOCATOR
 
 
+// Loads args from stack into R0 and R1
+// Tests if they are smis, jumps to label not_smi if not.
+static void TestBothArgumentsSmis(Assembler* assembler, Label* not_smi) {
+  __ ldr(R0, Address(SP, + 0 * kWordSize));
+  __ ldr(R1, Address(SP, + 1 * kWordSize));
+  __ orr(TMP, R0, Operand(R1));
+  __ tsti(TMP, kSmiTagMask);
+  __ b(not_smi, NE);
+}
+
+
 void Intrinsifier::Integer_addFromInteger(Assembler* assembler) {
-  return;
+  Label fall_through;
+  TestBothArgumentsSmis(assembler, &fall_through);  // Checks two smis.
+  __ adds(R0, R0, Operand(R1));  // Adds.
+  __ b(&fall_through, VS);  // Fall-through on overflow.
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::Integer_add(Assembler* assembler) {
-  return;
+  Integer_addFromInteger(assembler);
 }
 
 
 void Intrinsifier::Integer_subFromInteger(Assembler* assembler) {
-  return;
+  Label fall_through;
+  TestBothArgumentsSmis(assembler, &fall_through);
+  __ subs(R0, R0, Operand(R1));  // Subtract.
+  __ b(&fall_through, VS);  // Fall-through on overflow.
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::Integer_sub(Assembler* assembler) {
-  return;
+  Label fall_through;
+  TestBothArgumentsSmis(assembler, &fall_through);
+  __ subs(R0, R1, Operand(R0));  // Subtract.
+  __ b(&fall_through, VS);  // Fall-through on overflow.
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::Integer_mulFromInteger(Assembler* assembler) {
-  return;
+  Label fall_through;
+
+  TestBothArgumentsSmis(assembler, &fall_through);  // checks two smis
+  __ SmiUntag(R0);  // Untags R6. We only want result shifted by one.
+
+  __ mul(TMP, R0, R1);
+  __ smulh(TMP2, R0, R1);
+  // TMP: result bits 64..127.
+  __ cmp(TMP2, Operand(TMP, ASR, 63));
+  __ b(&fall_through, NE);
+  __ mov(R0, TMP);
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::Integer_mul(Assembler* assembler) {
-  return;
+  Integer_mulFromInteger(assembler);
 }
 
 
+// Optimizations:
+// - result is 0 if:
+//   - left is 0
+//   - left equals right
+// - result is left if
+//   - left > 0 && left < right
+// R1: Tagged left (dividend).
+// R0: Tagged right (divisor).
+// Returns with result in R0, OR:
+//   R1: Untagged result (remainder).
+static void EmitRemainderOperation(Assembler* assembler) {
+  Label return_zero, modulo;
+  const Register left = R1;
+  const Register right = R0;
+  const Register result = R1;
+  const Register tmp = R2;
+  ASSERT(left == result);
+
+  // Check for quick zero results.
+  __ CompareRegisters(left, ZR);
+  __ b(&return_zero, EQ);
+  __ CompareRegisters(left, right);
+  __ b(&return_zero, EQ);
+
+  // Check if result should be left.
+  __ CompareRegisters(left, ZR);
+  __ b(&modulo, LT);
+  // left is positive.
+  __ CompareRegisters(left, right);
+  // left is less than right, result is left.
+  __ b(&modulo, GT);
+  __ mov(R0, left);
+  __ ret();
+
+  __ Bind(&return_zero);
+  __ mov(R0, ZR);
+  __ ret();
+
+  __ Bind(&modulo);
+  // result <- left - right * (left / right)
+  __ SmiUntag(left);
+  __ SmiUntag(right);
+
+  __ sdiv(tmp, left, right);
+  __ msub(result, right, tmp, left);  // result <- left - right * tmp
+}
+
+
 // Implementation:
 //  res = left % right;
 //  if (res < 0) {
@@ -149,180 +595,518 @@
 //    }
 //  }
 void Intrinsifier::Integer_moduloFromInteger(Assembler* assembler) {
-  return;
+  // Check to see if we have integer division
+  Label neg_remainder, fall_through;
+  __ ldr(R1, Address(SP, + 0 * kWordSize));
+  __ ldr(R0, Address(SP, + 1 * kWordSize));
+  __ orr(TMP, R0, Operand(R1));
+  __ tsti(TMP, kSmiTagMask);
+  __ b(&fall_through, NE);
+  // R1: Tagged left (dividend).
+  // R0: Tagged right (divisor).
+  // Check if modulo by zero -> exception thrown in main function.
+  __ CompareRegisters(R0, ZR);
+  __ b(&fall_through, EQ);
+  EmitRemainderOperation(assembler);
+  // Untagged right in R0. Untagged remainder result in R1.
+
+  __ CompareRegisters(R1, ZR);
+  __ b(&neg_remainder, LT);
+  __ Lsl(R0, R1, 1);  // Tag and move result to R0.
+  __ ret();
+
+  __ Bind(&neg_remainder);
+  // Result is negative, adjust it.
+  __ CompareRegisters(R0, ZR);
+  __ sub(TMP, R1, Operand(R0));
+  __ add(TMP2, R1, Operand(R0));
+  __ csel(R0, TMP2, TMP, GE);
+  __ SmiTag(R0);
+  __ ret();
+
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::Integer_truncDivide(Assembler* assembler) {
-  return;
+  // Check to see if we have integer division
+  Label fall_through;
+
+  TestBothArgumentsSmis(assembler, &fall_through);
+  __ CompareRegisters(R0, ZR);
+  __ b(&fall_through, EQ);  // If b is 0, fall through.
+
+  __ SmiUntag(R0);
+  __ SmiUntag(R1);
+
+  __ sdiv(R0, R1, R0);
+
+  // Check the corner case of dividing the 'MIN_SMI' with -1, in which case we
+  // cannot tag the result.
+  __ CompareImmediate(R0, 0x4000000000000000, kNoPP);
+  __ b(&fall_through, EQ);
+  __ SmiTag(R0);  // Not equal. Okay to tag and return.
+  __ ret();  // Return.
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::Integer_negate(Assembler* assembler) {
-  return;
+  Label fall_through;
+  __ ldr(R0, Address(SP, + 0 * kWordSize));  // Grab first argument.
+  __ tsti(R0, kSmiTagMask);  // Test for Smi.
+  __ b(&fall_through, NE);
+  __ negs(R0, R0);
+  __ b(&fall_through, VS);
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::Integer_bitAndFromInteger(Assembler* assembler) {
-  return;
+  Label fall_through;
+  TestBothArgumentsSmis(assembler, &fall_through);  // Checks two smis.
+  __ and_(R0, R0, Operand(R1));
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::Integer_bitAnd(Assembler* assembler) {
-  return;
+  Integer_bitAndFromInteger(assembler);
 }
 
 
 void Intrinsifier::Integer_bitOrFromInteger(Assembler* assembler) {
-  return;
+  Label fall_through;
+  TestBothArgumentsSmis(assembler, &fall_through);  // Checks two smis.
+  __ orr(R0, R0, Operand(R1));
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::Integer_bitOr(Assembler* assembler) {
-  return;
+  Integer_bitOrFromInteger(assembler);
 }
 
 
 void Intrinsifier::Integer_bitXorFromInteger(Assembler* assembler) {
-  return;
+  Label fall_through;
+
+  TestBothArgumentsSmis(assembler, &fall_through);  // Checks two smis.
+  __ eor(R0, R0, Operand(R1));
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::Integer_bitXor(Assembler* assembler) {
-  return;
+  Integer_bitXorFromInteger(assembler);
 }
 
 
 void Intrinsifier::Integer_shl(Assembler* assembler) {
-  return;
+  ASSERT(kSmiTagShift == 1);
+  ASSERT(kSmiTag == 0);
+  const Register right = R0;
+  const Register left = R1;
+  const Register temp = R2;
+  const Register result = R0;
+  Label fall_through;
+
+  TestBothArgumentsSmis(assembler, &fall_through);
+  __ CompareImmediate(
+      right, reinterpret_cast<int64_t>(Smi::New(Smi::kBits)), PP);
+  __ b(&fall_through, CS);
+
+  // Left is not a constant.
+  // Check if count too large for handling it inlined.
+  __ Asr(TMP, right, kSmiTagSize);  // SmiUntag right into TMP.
+  // Overflow test (preserve left, right, and TMP);
+  __ lslv(temp, left, TMP);
+  __ asrv(TMP2, temp, TMP);
+  __ CompareRegisters(left, TMP2);
+  __ b(&fall_through, NE);  // Overflow.
+  // Shift for result now we know there is no overflow.
+  __ lslv(result, left, TMP);
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
+static void CompareIntegers(Assembler* assembler, Condition true_condition) {
+  Label fall_through, true_label;
+  TestBothArgumentsSmis(assembler, &fall_through);
+  // R0 contains the right argument, R1 the left.
+  __ CompareRegisters(R1, R0);
+  __ LoadObject(R0, Bool::False(), PP);
+  __ LoadObject(TMP, Bool::True(), PP);
+  __ csel(R0, TMP, R0, true_condition);
+  __ ret();
+  __ Bind(&fall_through);
+}
+
+
 void Intrinsifier::Integer_greaterThanFromInt(Assembler* assembler) {
-  return;
+  CompareIntegers(assembler, LT);
 }
 
 
 void Intrinsifier::Integer_lessThan(Assembler* assembler) {
-  return;
+  Integer_greaterThanFromInt(assembler);
 }
 
 
 void Intrinsifier::Integer_greaterThan(Assembler* assembler) {
-  return;
+  CompareIntegers(assembler, GT);
 }
 
 
 void Intrinsifier::Integer_lessEqualThan(Assembler* assembler) {
-  return;
+  CompareIntegers(assembler, LE);
 }
 
 
 void Intrinsifier::Integer_greaterEqualThan(Assembler* assembler) {
-  return;
+  CompareIntegers(assembler, GE);
 }
 
 
 // This is called for Smi, Mint and Bigint receivers. The right argument
 // can be Smi, Mint, Bigint or double.
 void Intrinsifier::Integer_equalToInteger(Assembler* assembler) {
-  return;
+  Label fall_through, true_label, check_for_mint;
+  // For integer receiver '===' check first.
+  __ ldr(R0, Address(SP, 0 * kWordSize));
+  __ ldr(R1, Address(SP, 1 * kWordSize));
+  __ cmp(R0, Operand(R1));
+  __ b(&true_label, EQ);
+
+  __ orr(R2, R0, Operand(R1));
+  __ tsti(R2, kSmiTagMask);
+  __ b(&check_for_mint, NE);  // If R0 or R1 is not a smi do Mint checks.
+
+  // Both arguments are smi, '===' is good enough.
+  __ LoadObject(R0, Bool::False(), PP);
+  __ ret();
+  __ Bind(&true_label);
+  __ LoadObject(R0, Bool::True(), PP);
+  __ ret();
+
+  // At least one of the arguments was not Smi.
+  Label receiver_not_smi;
+  __ Bind(&check_for_mint);
+
+  __ tsti(R1, kSmiTagMask);  // Check receiver.
+  __ b(&receiver_not_smi, NE);
+
+  // Left (receiver) is Smi, return false if right is not Double.
+  // Note that an instance of Mint or Bigint never contains a value that can be
+  // represented by Smi.
+
+  __ CompareClassId(R0, kDoubleCid, kNoPP);
+  __ b(&fall_through, EQ);
+  __ LoadObject(R0, Bool::False(), PP);  // Smi == Mint -> false.
+  __ ret();
+
+  __ Bind(&receiver_not_smi);
+  // R1: receiver.
+
+  __ CompareClassId(R1, kMintCid, kNoPP);
+  __ b(&fall_through, NE);
+  // Receiver is Mint, return false if right is Smi.
+  __ tsti(R0, kSmiTagMask);
+  __ b(&fall_through, NE);
+  __ LoadObject(R0, Bool::False(), PP);
+  __ ret();
+  // TODO(srdjan): Implement Mint == Mint comparison.
+
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::Integer_equal(Assembler* assembler) {
-  return;
+  Integer_equalToInteger(assembler);
 }
 
 
 void Intrinsifier::Integer_sar(Assembler* assembler) {
-  return;
+  Label fall_through;
+
+  TestBothArgumentsSmis(assembler, &fall_through);
+  // Shift amount in R0. Value to shift in R1.
+
+  // Fall through if shift amount is negative.
+  __ SmiUntag(R0);
+  __ CompareRegisters(R0, ZR);
+  __ b(&fall_through, LT);
+
+  // If shift amount is bigger than 63, set to 63.
+  __ LoadImmediate(TMP, 0x3F, kNoPP);
+  __ CompareRegisters(R0, TMP);
+  __ csel(R0, TMP, R0, GT);
+  __ SmiUntag(R1);
+  __ asrv(R0, R1, R0);
+  __ SmiTag(R0);
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::Smi_bitNegate(Assembler* assembler) {
-  return;
+  __ ldr(R0, Address(SP, 0 * kWordSize));
+  __ mvn(R0, R0);
+  __ andi(R0, R0, ~kSmiTagMask);  // Remove inverted smi-tag.
+  __ ret();
 }
 
 
 void Intrinsifier::Smi_bitLength(Assembler* assembler) {
-  return;
+  // TODO(sra): Implement as word-length - CLZ.
 }
 
 
+// Check if the last argument is a double, jump to label 'is_smi' if smi
+// (easy to convert to double), otherwise jump to label 'not_double_smi',
+// Returns the last argument in R0.
+static void TestLastArgumentIsDouble(Assembler* assembler,
+                                     Label* is_smi,
+                                     Label* not_double_smi) {
+  __ ldr(R0, Address(SP, 0 * kWordSize));
+  __ tsti(R0, kSmiTagMask);
+  __ b(is_smi, EQ);
+  __ CompareClassId(R0, kDoubleCid, kNoPP);
+  __ b(not_double_smi, NE);
+  // Fall through with Double in R0.
+}
+
+
+// Both arguments on stack, arg0 (left) is a double, arg1 (right) is of unknown
+// type. Return true or false object in the register R0. Any NaN argument
+// returns false. Any non-double arg1 causes control flow to fall through to the
+// slow case (compiled method body).
+static void CompareDoubles(Assembler* assembler, Condition true_condition) {
+  Label fall_through, is_smi, double_op, not_nan;
+
+  TestLastArgumentIsDouble(assembler, &is_smi, &fall_through);
+  // Both arguments are double, right operand is in R0.
+
+  __ LoadDFieldFromOffset(V1, R0, Double::value_offset(), kNoPP);
+  __ Bind(&double_op);
+  __ ldr(R0, Address(SP, 1 * kWordSize));  // Left argument.
+  __ LoadDFieldFromOffset(V0, R0, Double::value_offset(), kNoPP);
+
+  __ fcmpd(V0, V1);
+  __ LoadObject(R0, Bool::False(), PP);
+  // Return false if D0 or D1 was NaN before checking true condition.
+  __ b(&not_nan, VC);
+  __ ret();
+  __ Bind(&not_nan);
+  __ LoadObject(TMP, Bool::True(), PP);
+  __ csel(R0, TMP, R0, true_condition);
+  __ ret();
+
+  __ Bind(&is_smi);  // Convert R0 to a double.
+  __ SmiUntag(R0);
+  __ scvtfd(V1, R0);
+  __ b(&double_op);  // Then do the comparison.
+  __ Bind(&fall_through);
+}
+
+
 void Intrinsifier::Double_greaterThan(Assembler* assembler) {
-  return;
+  CompareDoubles(assembler, HI);
 }
 
 
 void Intrinsifier::Double_greaterEqualThan(Assembler* assembler) {
-  return;
+  CompareDoubles(assembler, CS);
 }
 
 
 void Intrinsifier::Double_lessThan(Assembler* assembler) {
-  return;
+  CompareDoubles(assembler, CC);
 }
 
 
 void Intrinsifier::Double_equal(Assembler* assembler) {
-  return;
+  CompareDoubles(assembler, EQ);
 }
 
 
 void Intrinsifier::Double_lessEqualThan(Assembler* assembler) {
-  return;
+  CompareDoubles(assembler, LS);
 }
 
 
+// Expects left argument to be double (receiver). Right argument is unknown.
+// Both arguments are on stack.
+static void DoubleArithmeticOperations(Assembler* assembler, Token::Kind kind) {
+  Label fall_through;
+
+  TestLastArgumentIsDouble(assembler, &fall_through, &fall_through);
+  // Both arguments are double, right operand is in R0.
+  __ LoadDFieldFromOffset(V1, R0, Double::value_offset(), kNoPP);
+  __ ldr(R0, Address(SP, 1 * kWordSize));  // Left argument.
+  __ LoadDFieldFromOffset(V0, R0, Double::value_offset(), kNoPP);
+  switch (kind) {
+    case Token::kADD: __ faddd(V0, V0, V1); break;
+    case Token::kSUB: __ fsubd(V0, V0, V1); break;
+    case Token::kMUL: __ fmuld(V0, V0, V1); break;
+    case Token::kDIV: __ fdivd(V0, V0, V1); break;
+    default: UNREACHABLE();
+  }
+  const Class& double_class = Class::Handle(
+      Isolate::Current()->object_store()->double_class());
+  __ TryAllocate(double_class, &fall_through, R0, R1, kNoPP);
+  __ StoreDFieldToOffset(V0, R0, Double::value_offset(), kNoPP);
+  __ ret();
+  __ Bind(&fall_through);
+}
+
+
 void Intrinsifier::Double_add(Assembler* assembler) {
-  return;
+  DoubleArithmeticOperations(assembler, Token::kADD);
 }
 
 
 void Intrinsifier::Double_mul(Assembler* assembler) {
-  return;
+  DoubleArithmeticOperations(assembler, Token::kMUL);
 }
 
 
 void Intrinsifier::Double_sub(Assembler* assembler) {
-  return;
+  DoubleArithmeticOperations(assembler, Token::kSUB);
 }
 
 
 void Intrinsifier::Double_div(Assembler* assembler) {
-  return;
+  DoubleArithmeticOperations(assembler, Token::kDIV);
 }
 
 
 // Left is double right is integer (Bigint, Mint or Smi)
 void Intrinsifier::Double_mulFromInteger(Assembler* assembler) {
-  return;
+  Label fall_through;
+  // Only smis allowed.
+  __ ldr(R0, Address(SP, 0 * kWordSize));
+  __ tsti(R0, kSmiTagMask);
+  __ b(&fall_through, NE);
+  // Is Smi.
+  __ SmiUntag(R0);
+  __ scvtfd(V1, R0);
+  __ ldr(R0, Address(SP, 1 * kWordSize));
+  __ LoadDFieldFromOffset(V0, R0, Double::value_offset(), kNoPP);
+  __ fmuld(V0, V0, V1);
+  const Class& double_class = Class::Handle(
+      Isolate::Current()->object_store()->double_class());
+  __ TryAllocate(double_class, &fall_through, R0, R1, kNoPP);
+  __ StoreDFieldToOffset(V0, R0, Double::value_offset(), kNoPP);
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::Double_fromInteger(Assembler* assembler) {
-  return;
+  Label fall_through;
+
+  __ ldr(R0, Address(SP, 0 * kWordSize));
+  __ tsti(R0, kSmiTagMask);
+  __ b(&fall_through, NE);
+  // Is Smi.
+  __ SmiUntag(R0);
+  __ scvtfd(V0, R0);
+  const Class& double_class = Class::Handle(
+      Isolate::Current()->object_store()->double_class());
+  __ TryAllocate(double_class, &fall_through, R0, R1, kNoPP);
+  __ StoreDFieldToOffset(V0, R0, Double::value_offset(), kNoPP);
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::Double_getIsNaN(Assembler* assembler) {
-  return;
+  Label is_true;
+  __ ldr(R0, Address(SP, 0 * kWordSize));
+  __ LoadDFieldFromOffset(V0, R0, Double::value_offset(), kNoPP);
+  __ fcmpd(V0, V0);
+  __ LoadObject(TMP, Bool::False(), PP);
+  __ LoadObject(R0, Bool::True(), PP);
+  __ csel(R0, TMP, R0, VC);
+  __ ret();
 }
 
 
 void Intrinsifier::Double_getIsNegative(Assembler* assembler) {
-  return;
+  const Register false_reg = R0;
+  const Register true_reg = R2;
+  Label is_false, is_true, is_zero;
+
+  __ ldr(R0, Address(SP, 0 * kWordSize));
+  __ LoadDFieldFromOffset(V0, R0, Double::value_offset(), kNoPP);
+  __ fcmpdz(V0);
+  __ LoadObject(true_reg, Bool::True(), PP);
+  __ LoadObject(false_reg, Bool::False(), PP);
+  __ b(&is_false, VS);  // NaN -> false.
+  __ b(&is_zero, EQ);  // Check for negative zero.
+  __ b(&is_false, CS);  // >= 0 -> false.
+
+  __ Bind(&is_true);
+  __ mov(R0, true_reg);
+
+  __ Bind(&is_false);
+  __ ret();
+
+  __ Bind(&is_zero);
+  // Check for negative zero by looking at the sign bit.
+  __ fmovrd(R1, V0);
+  __ Lsr(R1, R1, 63);
+  __ tsti(R1, 1);
+  __ csel(R0, true_reg, false_reg, NE);  // Sign bit set.
+  __ ret();
 }
 
 
 void Intrinsifier::Double_toInt(Assembler* assembler) {
-  return;
+  Label fall_through;
+
+  __ ldr(R0, Address(SP, 0 * kWordSize));
+  __ LoadDFieldFromOffset(V0, R0, Double::value_offset(), kNoPP);
+
+  // Explicit NaN check, since ARM gives an FPU exception if you try to
+  // convert NaN to an int.
+  __ fcmpd(V0, V0);
+  __ b(&fall_through, VS);
+
+  __ fcvtzds(R0, V0);
+  // Overflow is signaled with minint.
+  // Check for overflow and that it fits into Smi.
+  __ CompareImmediate(R0, 0xC000000000000000, kNoPP);
+  __ b(&fall_through, MI);
+  __ SmiTag(R0);
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::Math_sqrt(Assembler* assembler) {
-  return;
+  Label fall_through, is_smi, double_op;
+  TestLastArgumentIsDouble(assembler, &is_smi, &fall_through);
+  // Argument is double and is in R0.
+  __ LoadDFieldFromOffset(V1, R0, Double::value_offset(), kNoPP);
+  __ Bind(&double_op);
+  __ fsqrtd(V0, V1);
+  const Class& double_class = Class::Handle(
+      Isolate::Current()->object_store()->double_class());
+  __ TryAllocate(double_class, &fall_through, R0, R1, kNoPP);
+  __ StoreDFieldToOffset(V0, R0, Double::value_offset(), kNoPP);
+  __ ret();
+  __ Bind(&is_smi);
+  __ SmiUntag(R0);
+  __ scvtfd(V1, R0);
+  __ b(&double_op);
+  __ Bind(&fall_through);
 }
 
 
@@ -330,87 +1114,446 @@
 //    _state[kSTATE_LO] = state & _MASK_32;
 //    _state[kSTATE_HI] = state >> 32;
 void Intrinsifier::Random_nextState(Assembler* assembler) {
-  return;
+  const Library& math_lib = Library::Handle(Library::MathLibrary());
+  ASSERT(!math_lib.IsNull());
+  const Class& random_class = Class::Handle(
+      math_lib.LookupClassAllowPrivate(Symbols::_Random()));
+  ASSERT(!random_class.IsNull());
+  const Field& state_field = Field::ZoneHandle(
+      random_class.LookupInstanceField(Symbols::_state()));
+  ASSERT(!state_field.IsNull());
+  const Field& random_A_field = Field::ZoneHandle(
+      random_class.LookupStaticField(Symbols::_A()));
+  ASSERT(!random_A_field.IsNull());
+  ASSERT(random_A_field.is_const());
+  const Instance& a_value = Instance::Handle(random_A_field.value());
+  const int64_t a_int_value = Integer::Cast(a_value).AsInt64Value();
+
+  __ ldr(R0, Address(SP, 0 * kWordSize));  // Receiver.
+  __ ldr(R1, FieldAddress(R0, state_field.Offset()));  // Field '_state'.
+
+  // Addresses of _state[0].
+  const int64_t disp =
+      FlowGraphCompiler::DataOffsetFor(kTypedDataUint32ArrayCid) -
+      kHeapObjectTag;
+
+  __ LoadImmediate(R0, a_int_value, kNoPP);
+  __ LoadFromOffset(R2, R1, disp, kNoPP);
+  __ Lsr(R3, R2, 32);
+  __ andi(R2, R2, 0xffffffff);
+  __ mul(R2, R0, R2);
+  __ add(R2, R2, Operand(R3));
+  __ StoreToOffset(R2, R1, disp, kNoPP);
+  __ ret();
 }
 
 
 void Intrinsifier::Object_equal(Assembler* assembler) {
-  return;
+  __ ldr(R0, Address(SP, 0 * kWordSize));
+  __ ldr(R1, Address(SP, 1 * kWordSize));
+  __ cmp(R0, Operand(R1));
+  __ LoadObject(R0, Bool::False(), PP);
+  __ LoadObject(TMP, Bool::True(), PP);
+  __ csel(R0, TMP, R0, EQ);
+  __ ret();
 }
 
 
 void Intrinsifier::String_getHashCode(Assembler* assembler) {
-  return;
+  Label fall_through;
+  __ ldr(R0, Address(SP, 0 * kWordSize));
+  __ ldr(R0, FieldAddress(R0, String::hash_offset()));
+  __ CompareRegisters(R0, ZR);
+  __ b(&fall_through, EQ);
+  __ ret();
+  // Hash not yet computed.
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::String_getLength(Assembler* assembler) {
-  return;
+  __ ldr(R0, Address(SP, 0 * kWordSize));
+  __ ldr(R0, FieldAddress(R0, String::length_offset()));
+  __ ret();
 }
 
 
 void Intrinsifier::String_codeUnitAt(Assembler* assembler) {
-  return;
+  Label fall_through, try_two_byte_string;
+
+  __ ldr(R1, Address(SP, 0 * kWordSize));  // Index.
+  __ ldr(R0, Address(SP, 1 * kWordSize));  // String.
+  __ tsti(R1, kSmiTagMask);
+  __ b(&fall_through, NE);  // Index is not a Smi.
+  // Range check.
+  __ ldr(R2, FieldAddress(R0, String::length_offset()));
+  __ cmp(R1, Operand(R2));
+  __ b(&fall_through, CS);  // Runtime throws exception.
+  __ CompareClassId(R0, kOneByteStringCid, kNoPP);
+  __ b(&try_two_byte_string, NE);
+  __ SmiUntag(R1);
+  __ AddImmediate(R0, R0, OneByteString::data_offset() - kHeapObjectTag, kNoPP);
+  __ ldr(R0, Address(R0, R1), kUnsignedByte);
+  __ SmiTag(R0);
+  __ ret();
+
+  __ Bind(&try_two_byte_string);
+  __ CompareClassId(R0, kTwoByteStringCid, kNoPP);
+  __ b(&fall_through, NE);
+  ASSERT(kSmiTagShift == 1);
+  __ AddImmediate(R0, R0, TwoByteString::data_offset() - kHeapObjectTag, kNoPP);
+  __ ldr(R0, Address(R0, R1), kUnsignedHalfword);
+  __ SmiTag(R0);
+  __ ret();
+
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::String_getIsEmpty(Assembler* assembler) {
-  return;
+  __ ldr(R0, Address(SP, 0 * kWordSize));
+  __ ldr(R0, FieldAddress(R0, String::length_offset()));
+  __ cmp(R0, Operand(Smi::RawValue(0)));
+  __ LoadObject(R0, Bool::True(), PP);
+  __ LoadObject(TMP, Bool::False(), PP);
+  __ csel(R0, TMP, R0, NE);
+  __ ret();
 }
 
 
 void Intrinsifier::OneByteString_getHashCode(Assembler* assembler) {
-  return;
+  Label compute_hash;
+  __ ldr(R1, Address(SP, 0 * kWordSize));  // OneByteString object.
+  __ ldr(R0, FieldAddress(R1, String::hash_offset()));
+  __ CompareRegisters(R0, ZR);
+  __ b(&compute_hash, EQ);
+  __ ret();  // Return if already computed.
+
+  __ Bind(&compute_hash);
+  __ ldr(R2, FieldAddress(R1, String::length_offset()));
+  __ SmiUntag(R2);
+
+  Label done;
+  // If the string is empty, set the hash to 1, and return.
+  __ CompareRegisters(R2, ZR);
+  __ b(&done, EQ);
+
+  __ mov(R3, ZR);
+  __ AddImmediate(R6, R1, OneByteString::data_offset() - kHeapObjectTag, kNoPP);
+  // R1: Instance of OneByteString.
+  // R2: String length, untagged integer.
+  // R3: Loop counter, untagged integer.
+  // R6: String data.
+  // R0: Hash code, untagged integer.
+
+  Label loop;
+  // Add to hash code: (hash_ is uint32)
+  // hash_ += ch;
+  // hash_ += hash_ << 10;
+  // hash_ ^= hash_ >> 6;
+  // Get one characters (ch).
+  __ Bind(&loop);
+  __ ldr(R7, Address(R6, R3), kUnsignedByte);
+  // R7: ch.
+  __ add(R3, R3, Operand(1));
+  __ addw(R0, R0, Operand(R7));
+  __ addw(R0, R0, Operand(R0, LSL, 10));
+  __ eorw(R0, R0, Operand(R0, LSR, 6));
+  __ cmp(R3, Operand(R2));
+  __ b(&loop, NE);
+
+  // Finalize.
+  // hash_ += hash_ << 3;
+  // hash_ ^= hash_ >> 11;
+  // hash_ += hash_ << 15;
+  __ addw(R0, R0, Operand(R0, LSL, 3));
+  __ eorw(R0, R0, Operand(R0, LSR, 11));
+  __ addw(R0, R0, Operand(R0, LSL, 15));
+  // hash_ = hash_ & ((static_cast<intptr_t>(1) << bits) - 1);
+  __ AndImmediate(
+      R0, R0, (static_cast<intptr_t>(1) << String::kHashBits) - 1, kNoPP);
+  __ CompareRegisters(R0, ZR);
+  // return hash_ == 0 ? 1 : hash_;
+  __ Bind(&done);
+  __ csinc(R0, R0, ZR, NE);  // R0 <- (R0 != 0) ? R0 : (ZR + 1).
+  __ SmiTag(R0);
+  __ str(R0, FieldAddress(R1, String::hash_offset()));
+  __ ret();
 }
 
 
+// Allocates one-byte string of length 'end - start'. The content is not
+// initialized.
+// 'length-reg' (R2) contains tagged length.
+// Returns new string as tagged pointer in R0.
+static void TryAllocateOnebyteString(Assembler* assembler,
+                                     Label* ok,
+                                     Label* failure) {
+  const Register length_reg = R2;
+  Label fail;
+
+  __ mov(R6, length_reg);  // Save the length register.
+  __ SmiUntag(length_reg);
+  const intptr_t fixed_size = sizeof(RawString) + kObjectAlignment - 1;
+  __ AddImmediate(length_reg, length_reg, fixed_size, kNoPP);
+  __ andi(length_reg, length_reg, ~(kObjectAlignment - 1));
+
+  Isolate* isolate = Isolate::Current();
+  Heap* heap = isolate->heap();
+
+  __ LoadImmediate(R3, heap->TopAddress(), kNoPP);
+  __ ldr(R0, Address(R3));
+
+  // length_reg: allocation size.
+  __ adds(R1, R0, Operand(length_reg));
+  __ b(&fail, VS);  // Fail on overflow.
+
+  // Check if the allocation fits into the remaining space.
+  // R0: potential new object start.
+  // R1: potential next object start.
+  // R2: allocation size.
+  // R3: heap->Top->Address().
+  __ LoadImmediate(R7, heap->EndAddress(), kNoPP);
+  __ ldr(R7, Address(R7));
+  __ cmp(R1, Operand(R7));
+  __ b(&fail, CS);
+
+  // Successfully allocated the object(s), now update top to point to
+  // next object start and initialize the object.
+  __ str(R1, Address(R3));
+  __ AddImmediate(R0, R0, kHeapObjectTag, kNoPP);
+  __ UpdateAllocationStatsWithSize(kOneByteStringCid, R2, R3, kNoPP);
+
+  // Initialize the tags.
+  // R0: new object start as a tagged pointer.
+  // R1: new object end address.
+  // R2: allocation size.
+  {
+    const intptr_t shift = RawObject::kSizeTagPos - kObjectAlignmentLog2;
+    const Class& cls =
+        Class::Handle(isolate->object_store()->one_byte_string_class());
+
+    __ CompareImmediate(R2, RawObject::SizeTag::kMaxSizeTag, kNoPP);
+    __ Lsl(R2, R2, shift);
+    __ csel(R2, R2, ZR, LS);
+
+    // Get the class index and insert it into the tags.
+    // R2: size and bit tags.
+    __ LoadImmediate(TMP, RawObject::ClassIdTag::encode(cls.id()), kNoPP);
+    __ orr(R2, R2, Operand(TMP));
+    __ str(R2, FieldAddress(R0, String::tags_offset()));  // Store tags.
+  }
+
+  // Set the length field using the saved length (R6).
+  __ StoreIntoObjectNoBarrier(R0,
+                              FieldAddress(R0, String::length_offset()),
+                              R6);
+  // Clear hash.
+  __ mov(TMP, ZR);
+  __ str(TMP, FieldAddress(R0, String::hash_offset()));
+  __ b(ok);
+
+  __ Bind(&fail);
+  __ b(failure);
+}
+
+
 // Arg0: OneByteString (receiver).
 // Arg1: Start index as Smi.
 // Arg2: End index as Smi.
 // The indexes must be valid.
 void Intrinsifier::OneByteString_substringUnchecked(Assembler* assembler) {
-  return;
+  const intptr_t kStringOffset = 2 * kWordSize;
+  const intptr_t kStartIndexOffset = 1 * kWordSize;
+  const intptr_t kEndIndexOffset = 0 * kWordSize;
+  Label fall_through, ok;
+
+  __ ldr(R2, Address(SP, kEndIndexOffset));
+  __ ldr(TMP, Address(SP, kStartIndexOffset));
+  __ orr(R3, R2,  Operand(TMP));
+  __ tsti(R3, kSmiTagMask);
+  __ b(&fall_through, NE);  // 'start', 'end' not Smi.
+
+  __ sub(R2, R2, Operand(TMP));
+  TryAllocateOnebyteString(assembler, &ok, &fall_through);
+  __ Bind(&ok);
+  // R0: new string as tagged pointer.
+  // Copy string.
+  __ ldr(R3, Address(SP, kStringOffset));
+  __ ldr(R1, Address(SP, kStartIndexOffset));
+  __ SmiUntag(R1);
+  __ add(R3, R3, Operand(R1));
+  // Calculate start address and untag (- 1).
+  __ AddImmediate(R3, R3, OneByteString::data_offset() - 1, kNoPP);
+
+  // R3: Start address to copy from (untagged).
+  // R1: Untagged start index.
+  __ ldr(R2, Address(SP, kEndIndexOffset));
+  __ SmiUntag(R2);
+  __ sub(R2, R2, Operand(R1));
+
+  // R3: Start address to copy from (untagged).
+  // R2: Untagged number of bytes to copy.
+  // R0: Tagged result string.
+  // R6: Pointer into R3.
+  // R7: Pointer into R0.
+  // R1: Scratch register.
+  Label loop, done;
+  __ cmp(R2, Operand(0));
+  __ b(&done, LE);
+  __ mov(R6, R3);
+  __ mov(R7, R0);
+  __ Bind(&loop);
+  __ ldr(R1, Address(R6), kUnsignedByte);
+  __ AddImmediate(R6, R6, 1, kNoPP);
+  __ sub(R2, R2, Operand(1));
+  __ cmp(R2, Operand(0));
+  __ str(R1, FieldAddress(R7, OneByteString::data_offset()), kUnsignedByte);
+  __ AddImmediate(R7, R7, 1, kNoPP);
+  __ b(&loop, GT);
+
+  __ Bind(&done);
+  __ ret();
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::OneByteString_setAt(Assembler* assembler) {
-  return;
+  __ ldr(R2, Address(SP, 0 * kWordSize));  // Value.
+  __ ldr(R1, Address(SP, 1 * kWordSize));  // Index.
+  __ ldr(R0, Address(SP, 2 * kWordSize));  // OneByteString.
+  __ SmiUntag(R1);
+  __ SmiUntag(R2);
+  __ AddImmediate(R3, R0, OneByteString::data_offset() - kHeapObjectTag, kNoPP);
+  __ str(R2, Address(R3, R1), kUnsignedByte);
+  __ ret();
 }
 
 
 void Intrinsifier::OneByteString_allocate(Assembler* assembler) {
-  return;
+  Label fall_through, ok;
+
+  __ ldr(R2, Address(SP, 0 * kWordSize));  // Length.
+  TryAllocateOnebyteString(assembler, &ok, &fall_through);
+
+  __ Bind(&ok);
+  __ ret();
+
+  __ Bind(&fall_through);
 }
 
 
 // TODO(srdjan): Add combinations (one-byte/two-byte/external strings).
 void StringEquality(Assembler* assembler, intptr_t string_cid) {
-  return;
+  Label fall_through, is_true, is_false, loop;
+  __ ldr(R0, Address(SP, 1 * kWordSize));  // This.
+  __ ldr(R1, Address(SP, 0 * kWordSize));  // Other.
+
+  // Are identical?
+  __ cmp(R0, Operand(R1));
+  __ b(&is_true, EQ);
+
+  // Is other OneByteString?
+  __ tsti(R1, kSmiTagMask);
+  __ b(&fall_through, EQ);
+  __ CompareClassId(R1, string_cid, kNoPP);
+  __ b(&fall_through, NE);
+
+  // Have same length?
+  __ ldr(R2, FieldAddress(R0, String::length_offset()));
+  __ ldr(R3, FieldAddress(R1, String::length_offset()));
+  __ cmp(R2, Operand(R3));
+  __ b(&is_false, NE);
+
+  // Check contents, no fall-through possible.
+  // TODO(zra): try out other sequences.
+  ASSERT((string_cid == kOneByteStringCid) ||
+         (string_cid == kTwoByteStringCid));
+  const intptr_t offset = (string_cid == kOneByteStringCid) ?
+      OneByteString::data_offset() : TwoByteString::data_offset();
+  __ AddImmediate(R0, R0, offset - kHeapObjectTag, kNoPP);
+  __ AddImmediate(R1, R1, offset - kHeapObjectTag, kNoPP);
+  __ SmiUntag(R2);
+  __ Bind(&loop);
+  __ AddImmediate(R2, R2, -1, kNoPP);
+  __ CompareRegisters(R2, ZR);
+  __ b(&is_true, LT);
+  if (string_cid == kOneByteStringCid) {
+    __ ldr(R3, Address(R0), kUnsignedByte);
+    __ ldr(R4, Address(R1), kUnsignedByte);
+    __ AddImmediate(R0, R0, 1, kNoPP);
+    __ AddImmediate(R1, R1, 1, kNoPP);
+  } else if (string_cid == kTwoByteStringCid) {
+    __ ldr(R3, Address(R0), kUnsignedHalfword);
+    __ ldr(R4, Address(R1), kUnsignedHalfword);
+    __ AddImmediate(R0, R0, 2, kNoPP);
+    __ AddImmediate(R1, R1, 2, kNoPP);
+  } else {
+    UNIMPLEMENTED();
+  }
+  __ cmp(R3, Operand(R4));
+  __ b(&is_false, NE);
+  __ b(&loop);
+
+  __ Bind(&is_true);
+  __ LoadObject(R0, Bool::True(), PP);
+  __ ret();
+
+  __ Bind(&is_false);
+  __ LoadObject(R0, Bool::False(), PP);
+  __ ret();
+
+  __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::OneByteString_equality(Assembler* assembler) {
-  return;
+  StringEquality(assembler, kOneByteStringCid);
 }
 
 
 void Intrinsifier::TwoByteString_equality(Assembler* assembler) {
-  return;
+  StringEquality(assembler, kTwoByteStringCid);
 }
 
 
+// On stack: user tag (+0).
 void Intrinsifier::UserTag_makeCurrent(Assembler* assembler) {
-  return;
+  // R1: Isolate.
+  Isolate* isolate = Isolate::Current();
+  __ LoadImmediate(R1, reinterpret_cast<uword>(isolate), kNoPP);
+  // R0: Current user tag.
+  __ ldr(R0, Address(R1, Isolate::current_tag_offset()));
+  // R2: UserTag.
+  __ ldr(R2, Address(SP, + 0 * kWordSize));
+  // Set Isolate::current_tag_.
+  __ str(R2, Address(R1, Isolate::current_tag_offset()));
+  // R2: UserTag's tag.
+  __ ldr(R2, FieldAddress(R2, UserTag::tag_offset()));
+  // Set Isolate::user_tag_.
+  __ str(R2, Address(R1, Isolate::user_tag_offset()));
+  __ ret();
 }
 
 
-void Intrinsifier::Profiler_getCurrentTag(Assembler* assembler) {
-  return;
+void Intrinsifier::UserTag_defaultTag(Assembler* assembler) {
+  Isolate* isolate = Isolate::Current();
+  // Set return value to default tag address.
+  __ LoadImmediate(R0,
+      reinterpret_cast<uword>(isolate->object_store()) +
+                              ObjectStore::default_tag_offset(), kNoPP);
+  __ ldr(R0, Address(R0));
+  __ ret();
 }
 
 
-void Intrinsifier::UserTag_defaultTag(Assembler* assembler) {
-  return;
+void Intrinsifier::Profiler_getCurrentTag(Assembler* assembler) {
+  // R1: Default tag address.
+  Isolate* isolate = Isolate::Current();
+  __ LoadImmediate(R1, reinterpret_cast<uword>(isolate), kNoPP);
+  // Set return value to Isolate::current_tag_.
+  __ ldr(R0, Address(R1, Isolate::current_tag_offset()));
+  __ ret();
 }
 
 }  // namespace dart