Prevent deopt when assigning double values to typed arrays

src/ia32/stub-cache-ia32.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 3528 matching lines @@
   else
     __ j(not_equal, &check_heap_number);
 
   // smi case
   __ mov(ecx, eax);  // Preserve the value in eax.  Key is no longer needed.
   __ SmiUntag(ecx);
   __ mov(edi, FieldOperand(edi, ExternalArray::kExternalPointerOffset));
   // ecx: base pointer of external storage
   switch (array_type) {
     case kExternalPixelArray:
-      {  // Clamp the value to [0..255].
-        NearLabel done;
-        __ test(ecx, Immediate(0xFFFFFF00));
-        __ j(zero, &done);
-        __ setcc(negative, ecx);  // 1 if negative, 0 if positive.
-        __ dec_b(ecx);  // 0 if negative, 255 if positive.
-        __ bind(&done);
-      }
+      __ ClampUInt8(ecx);
       __ mov_b(Operand(edi, ebx, times_1, 0), ecx);
       break;
     case kExternalByteArray:
     case kExternalUnsignedByteArray:
       __ mov_b(Operand(edi, ebx, times_1, 0), ecx);
       break;
     case kExternalShortArray:
     case kExternalUnsignedShortArray:
       __ mov_w(Operand(edi, ebx, times_2, 0), ecx);
       break;
@@ skipping 135 matching lines @@
 
   return GetCode(flags);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32