Tests for GuardField length check along with bug fixes

runtime/vm/intermediate_language_arm.cc

Index: runtime/vm/intermediate_language_arm.cc
diff --git a/runtime/vm/intermediate_language_arm.cc b/runtime/vm/intermediate_language_arm.cc
index 01f1c1664ab4e22f4e2ea809613902dd19a9c48a..e5e60b880953795ccfe4fa0e714a15d493218fff 100644
--- a/runtime/vm/intermediate_language_arm.cc
+++ b/runtime/vm/intermediate_language_arm.cc
@@ -1609,13 +1609,43 @@ void GuardFieldInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
         if ((field_cid == kArrayCid) || (field_cid == kImmutableArrayCid)) {
           __ ldr(temp_reg,
                  FieldAddress(value_reg, Array::length_offset()));
-          __ CompareImmediate(temp_reg, field_length);
+          __ CompareImmediate(temp_reg, Smi::RawValue(field_length));
         } else if (RawObject::IsTypedDataClassId(field_cid)) {
           __ ldr(temp_reg,
                  FieldAddress(value_reg, TypedData::length_offset()));
-          __ CompareImmediate(temp_reg, field_length);
+          __ CompareImmediate(temp_reg, Smi::RawValue(field_length));
         } else {
           ASSERT(field_cid == kIllegalCid);
+          Label check_array, local_exit, local_fail;
+          __ CompareImmediate(value_cid_reg, kNullCid);
+          __ b(&local_fail, EQ);
+          // Check for typed data array.
+          __ CompareImmediate(value_cid_reg, kTypedDataFloat32x4ArrayCid);
+          __ b(&local_fail, GT);
+          __ CompareImmediate(value_cid_reg, kTypedDataInt8ArrayCid);
+          __ b(&check_array, LT);  // Could still be a regular array.
+          __ ldr(temp_reg,
+                 FieldAddress(value_reg, TypedData::length_offset()));
+          __ ldr(IP, field_length_operand);
+          __ cmp(temp_reg, ShifterOperand(IP));
+          __ b(&local_exit);  // Updated field length typed data array.
+          // Check for regular array.
+          __ Bind(&check_array);
+          __ CompareImmediate(value_cid_reg, kImmutableArrayCid);
+          __ b(&local_fail, GT);
+          __ CompareImmediate(value_cid_reg, kArrayCid);
+          __ b(&local_fail, LT);
+          __ ldr(temp_reg,
+                 FieldAddress(value_reg, Array::length_offset()));
+          __ ldr(IP, field_length_operand);
+          __ cmp(temp_reg, ShifterOperand(IP));
+          __ b(&local_exit);  // Updated field length from regular array.
+
+          __ Bind(&local_fail);
+          __ LoadImmediate(IP, Smi::RawValue(Field::kNoFixedLength));
+          __ str(IP, field_length_operand);
+
+          __ Bind(&local_exit);
           // Following branch cannot not occur, fall through.
         }
         __ b(fail, NE);
@@ -1637,15 +1667,16 @@ void GuardFieldInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
         if ((field_cid == kArrayCid) || (field_cid == kImmutableArrayCid)) {
           __ ldr(temp_reg,
                   FieldAddress(value_reg, Array::length_offset()));
-          __ CompareImmediate(temp_reg, field_length);
+          __ CompareImmediate(temp_reg, Smi::RawValue(field_length));
         } else if (RawObject::IsTypedDataClassId(field_cid)) {
           __ ldr(temp_reg,
                   FieldAddress(value_reg, TypedData::length_offset()));
-          __ CompareImmediate(temp_reg, field_length);
+          __ CompareImmediate(temp_reg, Smi::RawValue(field_length));
         } else {
           ASSERT(field_cid == kIllegalCid);
           // Following jump cannot not occur, fall through.
         }
+        __ b(fail, NE);
       }
       // Not identical, possibly null.
       __ Bind(&skip_length_check);
@@ -1686,7 +1717,7 @@ void GuardFieldInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
         __ b(&local_exit);  // Updated field length from regular array.
 
         __ Bind(&local_fail);
-        __ LoadImmediate(IP, Field::kNoFixedLength);
+        __ LoadImmediate(IP, Smi::RawValue(Field::kNoFixedLength));
         __ str(IP, field_length_operand);
 
         __ Bind(&local_exit);
@@ -1695,22 +1726,23 @@ void GuardFieldInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
       __ LoadImmediate(IP, value_cid);
       __ str(IP, field_cid_operand);
       __ str(IP, field_nullability_operand);
-      if ((value_cid == kArrayCid) || (value_cid == kImmutableArrayCid)) {
-        // Destroy value_cid_reg (safe because we are finished with it).
-        __ ldr(value_cid_reg,
-               FieldAddress(value_reg, Array::length_offset()));
-        __ str(value_cid_reg, field_length_operand);
-      } else if (RawObject::IsTypedDataClassId(value_cid)) {
-        // Destroy value_cid_reg (safe because we are finished with it).
-        __ ldr(value_cid_reg,
-                FieldAddress(value_reg, TypedData::length_offset()));
-        __ str(value_cid_reg, field_length_operand);
-      } else {
-        __ LoadImmediate(IP, Field::kNoFixedLength);
-        __ str(IP, field_length_operand);
+      if (field_has_length) {
+        if ((value_cid == kArrayCid) || (value_cid == kImmutableArrayCid)) {
+          // Destroy value_cid_reg (safe because we are finished with it).
+          __ ldr(value_cid_reg,
+                 FieldAddress(value_reg, Array::length_offset()));
+          __ str(value_cid_reg, field_length_operand);
+        } else if (RawObject::IsTypedDataClassId(value_cid)) {
+          // Destroy value_cid_reg (safe because we are finished with it).
+          __ ldr(value_cid_reg,
+                  FieldAddress(value_reg, TypedData::length_offset()));
+          __ str(value_cid_reg, field_length_operand);
+        } else {
+          __ LoadImmediate(IP, Smi::RawValue(Field::kNoFixedLength));
+          __ str(IP, field_length_operand);
+        }
       }
     }
-
     if (!ok_is_fall_through) {
       __ b(&ok);
     }