MIPS64: Load prototype from map in PropertyHandlerCompiler::CheckPrototypes.

Port 100db758

BUG=v8:3629
LOG=N

Review URL: https://codereview.chromium.org/755693002

Cr-Commit-Position: refs/heads/master@{#25497}

src/ic/mips64/handler-compiler-mips64.cc

@@ -411,12 +411,6 @@ Register PropertyHandlerCompiler::CheckPrototypes(
       reg = holder_reg;  // From now on the object will be in holder_reg.
       __ ld(reg, FieldMemOperand(scratch1, Map::kPrototypeOffset));
     } else {
-      // Two possible reasons for loading the prototype from the map:
-      // (1) Can't store references to new space in code.
-      // (2) Handler is shared for all receivers with the same prototype
-      //     map (but not necessarily the same prototype instance).
-      bool load_prototype_from_map =
-          heap()->InNewSpace(*prototype) || depth == 1;
       Register map_reg = scratch1;
       if (depth != 1 || check == CHECK_ALL_MAPS) {
         // CheckMap implicitly loads the map of |reg| into |map_reg|.
@@ -440,11 +434,7 @@ Register PropertyHandlerCompiler::CheckPrototypes(
 
       reg = holder_reg;  // From now on the object will be in holder_reg.
 
-      if (load_prototype_from_map) {
-        __ ld(reg, FieldMemOperand(map_reg, Map::kPrototypeOffset));
-      } else {
-        __ li(reg, Operand(prototype));
-      }
+      __ ld(reg, FieldMemOperand(map_reg, Map::kPrototypeOffset));
     }
 
     // Go to the next object in the prototype chain.