PPC: [compiler] Remove broken support for undetectable strings.

src/full-codegen/ppc/full-codegen-ppc.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_PPC
 
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
 #include "src/codegen.h"
 #include "src/compiler.h"
@@ skipping 4974 matching lines @@
 
   Factory* factory = isolate()->factory();
   if (String::Equals(check, factory->number_string())) {
     __ JumpIfSmi(r3, if_true);
     __ LoadP(r3, FieldMemOperand(r3, HeapObject::kMapOffset));
     __ LoadRoot(ip, Heap::kHeapNumberMapRootIndex);
     __ cmp(r3, ip);
     Split(eq, if_true, if_false, fall_through);
   } else if (String::Equals(check, factory->string_string())) {
     __ JumpIfSmi(r3, if_false);
-    // Check for undetectable objects => false.
     __ CompareObjectType(r3, r3, r4, FIRST_NONSTRING_TYPE);
-    __ bge(if_false);
-    __ lbz(r4, FieldMemOperand(r3, Map::kBitFieldOffset));
-    STATIC_ASSERT((1 << Map::kIsUndetectable) < 0x8000);
-    __ andi(r0, r4, Operand(1 << Map::kIsUndetectable));
-    Split(eq, if_true, if_false, fall_through, cr0);
+    Split(lt, if_true, if_false, fall_through);
   } else if (String::Equals(check, factory->symbol_string())) {
     __ JumpIfSmi(r3, if_false);
     __ CompareObjectType(r3, r3, r4, SYMBOL_TYPE);
     Split(eq, if_true, if_false, fall_through);
   } else if (String::Equals(check, factory->float32x4_string())) {
     __ JumpIfSmi(r3, if_false);
     __ CompareObjectType(r3, r3, r4, FLOAT32X4_TYPE);
     Split(eq, if_true, if_false, fall_through);
   } else if (String::Equals(check, factory->int32x4_string())) {
     __ JumpIfSmi(r3, if_false);
@@ skipping 340 matching lines @@
     return ON_STACK_REPLACEMENT;
   }
 
   DCHECK(interrupt_address ==
          isolate->builtins()->OsrAfterStackCheck()->entry());
   return OSR_AFTER_STACK_CHECK;
 }
 }  // namespace internal
 }  // namespace v8
 #endif  // V8_TARGET_ARCH_PPC