Tests for GuardField length check along with bug fixes

runtime/vm/intermediate_language_mips.cc

Index: runtime/vm/intermediate_language_mips.cc
diff --git a/runtime/vm/intermediate_language_mips.cc b/runtime/vm/intermediate_language_mips.cc
index d32428aaf63e6f757613c804a98670c53f03a3eb..e2c044e320df00871a4462ae2fff757231ad976e 100644
--- a/runtime/vm/intermediate_language_mips.cc
+++ b/runtime/vm/intermediate_language_mips.cc
@@ -1593,7 +1593,7 @@ void GuardFieldInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   __ TraceSimMsg("GuardFieldInstr");
   const intptr_t field_cid = field().guarded_cid();
   const intptr_t nullability = field().is_nullable() ? kNullCid : kIllegalCid;
-  const intptr_t field_length = field().guarded_list_length();
+  const intptr_t field_length = Smi::RawValue(field().guarded_list_length());
   const bool field_has_length = field().needs_length_check();
   const bool needs_value_temp_reg =
       (field_has_length || ((value()->Type()->ToCid() == kDynamicCid) &&
@@ -1640,7 +1640,7 @@ void GuardFieldInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
     }
 
     __ LoadObject(field_reg, Field::ZoneHandle(field().raw()));
-
+    int32_t raw_no_fixed_length = Smi::RawValue(Field::kNoFixedLength);
     FieldAddress field_cid_operand(field_reg, Field::guarded_cid_offset());
     FieldAddress field_nullability_operand(
         field_reg, Field::is_nullable_offset());
@@ -1672,7 +1672,33 @@ void GuardFieldInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
           __ subu(CMPRES1, TMP, CMPRES1);
         } else {
           ASSERT(field_cid == kIllegalCid);
-          __ LoadImmediate(CMPRES1, 0x1);
+          Label check_array, local_exit, local_fail;
+          __ BranchEqual(value_cid_reg, kNullCid, &local_fail);
+          // Check for typed data array.
+          __ BranchSignedGreater(value_cid_reg, kTypedDataFloat32x4ArrayCid,
+                                 &local_fail);
+          __ BranchSignedLess(value_cid_reg, kTypedDataInt8ArrayCid,
+                              &check_array);
+          __ lw(TMP, FieldAddress(value_reg, TypedData::length_offset()));
+          __ lw(CMPRES1, field_length_operand);
+          __ subu(CMPRES1, TMP, CMPRES1);
+          __ b(&local_exit);
+          // Check for regular array.
+          __ Bind(&check_array);
+          __ BranchSignedGreater(value_cid_reg, kImmutableArrayCid,
+                                 &local_fail);
+          __ BranchSignedLess(value_cid_reg, kArrayCid, &local_fail);
+          __ lw(TMP, FieldAddress(value_reg, Array::length_offset()));
+          __ lw(CMPRES1, field_length_operand);
+          __ subu(CMPRES1, TMP, CMPRES1);
+          __ b(&local_exit);
+
+          __ Bind(&local_fail);
+          // TODO(regis): TMP1 may conflict. Revisit.
+          __ LoadImmediate(TMP1, raw_no_fixed_length);
+          __ sw(TMP1, field_length_operand);
+
+          __ Bind(&local_exit);
         }
         __ bne(CMPRES1, ZR, fail);
       }
@@ -1699,18 +1725,18 @@ void GuardFieldInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
           ASSERT((value_cid_reg != value_reg) && (field_reg != value_cid_reg));
         }
         ASSERT(value_cid_reg != kNoRegister);
-        if ((field_cid == kArrayCid) || (field_cid == kImmutableArrayCid)) {
+        if ((value_cid == kArrayCid) || (value_cid == kImmutableArrayCid)) {
           __ lw(TMP, FieldAddress(value_reg, Array::length_offset()));
           __ LoadImmediate(CMPRES, field_length);
           __ subu(CMPRES, TMP, CMPRES);
-        } else if (RawObject::IsTypedDataClassId(field_cid)) {
+        } else if (RawObject::IsTypedDataClassId(value_cid)) {
           __ lw(TMP, FieldAddress(value_reg, TypedData::length_offset()));
           __ LoadImmediate(CMPRES, field_length);
           __ subu(CMPRES, TMP, CMPRES);
         } else {
           ASSERT(field_cid == kIllegalCid);
-          __ LoadImmediate(CMPRES, 0x1);
         }
+        __ bne(CMPRES, ZR, fail);
       }
       __ Bind(&skip_length_check);
     }
@@ -1748,7 +1774,7 @@ void GuardFieldInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
 
         __ Bind(&local_fail);
         // TODO(regis): TMP1 may conflict. Revisit.
-        __ LoadImmediate(TMP1, Field::kNoFixedLength);
+        __ LoadImmediate(TMP1, raw_no_fixed_length);
         __ sw(TMP1, field_length_operand);
 
         __ Bind(&local_exit);
@@ -1764,23 +1790,24 @@ void GuardFieldInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
       __ LoadImmediate(TMP1, value_cid);
       __ sw(TMP1, field_cid_operand);
       __ sw(TMP1, field_nullability_operand);
-      if ((value_cid == kArrayCid) || (value_cid == kImmutableArrayCid)) {
-        // Destroy value_cid_reg (safe because we are finished with it).
-        __ lw(value_cid_reg,
-              FieldAddress(value_reg, Array::length_offset()));
-        __ sw(value_cid_reg, field_length_operand);
-      } else if (RawObject::IsTypedDataClassId(value_cid)) {
-        // Destroy value_cid_reg (safe because we are finished with it).
-        __ lw(value_cid_reg,
-              FieldAddress(value_reg, TypedData::length_offset()));
-        __ sw(value_cid_reg, field_length_operand);
-      } else {
-        // Destroy value_cid_reg (safe because we are finished with it).
-        __ LoadImmediate(value_cid_reg, Field::kNoFixedLength);
-        __ sw(value_cid_reg, 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).
+          __ lw(value_cid_reg,
+                FieldAddress(value_reg, Array::length_offset()));
+          __ sw(value_cid_reg, field_length_operand);
+        } else if (RawObject::IsTypedDataClassId(value_cid)) {
+          // Destroy value_cid_reg (safe because we are finished with it).
+          __ lw(value_cid_reg,
+                FieldAddress(value_reg, TypedData::length_offset()));
+          __ sw(value_cid_reg, field_length_operand);
+        } else {
+          // Destroy value_cid_reg (safe because we are finished with it).
+          __ LoadImmediate(value_cid_reg, raw_no_fixed_length);
+          __ sw(value_cid_reg, field_length_operand);
+        }
       }
     }
-
     if (!ok_is_fall_through) {
       __ b(&ok);
     }