Small optimizations to parseInt

src/runtime.cc

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@@ skipping 3369 matching lines @@
     i += step;
   }
   return destination;
 }
 
 
 static Object* Runtime_StringParseInt(Arguments args) {
   NoHandleAllocation ha;
 
   CONVERT_CHECKED(String, s, args[0]);
-  CONVERT_DOUBLE_CHECKED(n, args[1]);
-  int radix = FastD2I(n);
+  CONVERT_SMI_CHECKED(radix, args[1]);

[Erik Corry, 2009/11/11 11:16:49]

This version doesn't work if the argument is not a Smi.  It throws an exception
instead of just working.  We should have a test that parseInt("100", 16.1) ==
256.

[Lasse Reichstein, 2009/11/11 11:43:34]

It's perfectly fine to throw an exception for a non-smi, if we only ever use it
with a smi (as we do, if TO_INT32 returns values in the range 2..36 as smis), so
this in itself is not a problem.
But yes, we do need some tests to see that we don't pass non-smis as arguments.

[Erik Corry, 2009/11/13 12:24:23]

My apologies, I was too fast with this comment.  The 16.1 case is caught in the
js code, so the patch LGTM.

 
   s->TryFlattenIfNotFlat();
 
   int len = s->length();
   int i;
 
   // Skip leading white space.
   for (i = 0; i < len && Scanner::kIsWhiteSpace.get(s->Get(i)); i++) ;
   if (i == len) return Heap::nan_value();
 
@@ skipping 4484 matching lines @@
   } else {
     // Handle last resort GC and make sure to allow future allocations
     // to grow the heap without causing GCs (if possible).
     Counters::gc_last_resort_from_js.Increment();
     Heap::CollectAllGarbage(false);
   }
 }
 
 
 } }  // namespace v8::internal