Implement Math.sin, cos and tan using table lookup and spline interpolation.

src/runtime.cc

 // Copyright 2012 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 5408 matching lines @@
   Handle<Object> object = args.at<Object>(0);
 
   if (object->IsJSFunction()) {
     JSFunction* func = JSFunction::cast(*object);
     func->shared()->set_native(true);
   }
   return isolate->heap()->undefined_value();
 }
 
 
+RUNTIME_FUNCTION(MaybeObject*, Runtime_SetInlineBuiltinFlag) {
+  SealHandleScope shs(isolate);
+  RUNTIME_ASSERT(args.length() == 1);
+
+  Handle<Object> object = args.at<Object>(0);
+
+  if (object->IsJSFunction()) {
+    JSFunction* func = JSFunction::cast(*object);
+    func->shared()->set_inline_builtin(true);
+  }
+  return isolate->heap()->undefined_value();
+}
+
+
 RUNTIME_FUNCTION(MaybeObject*, Runtime_StoreArrayLiteralElement) {
   HandleScope scope(isolate);
   RUNTIME_ASSERT(args.length() == 5);
   CONVERT_ARG_HANDLE_CHECKED(JSObject, object, 0);
   CONVERT_SMI_ARG_CHECKED(store_index, 1);
   Handle<Object> value = args.at<Object>(2);
   CONVERT_ARG_HANDLE_CHECKED(FixedArray, literals, 3);
   CONVERT_SMI_ARG_CHECKED(literal_index, 4);
 
   Object* raw_literal_cell = literals->get(literal_index);
@@ skipping 2401 matching lines @@
 RUNTIME_FUNCTION(MaybeObject*, Runtime_Math_tan) {
   SealHandleScope shs(isolate);
   ASSERT(args.length() == 1);
   isolate->counters()->math_tan()->Increment();
 
   CONVERT_DOUBLE_ARG_CHECKED(x, 0);
   return isolate->transcendental_cache()->Get(TranscendentalCache::TAN, x);
 }
 
 
+RUNTIME_FUNCTION(MaybeObject*, Runtime_PopulateTrigonometricTable) {
+  HandleScope scope(isolate);
+  ASSERT(args.length() == 3);
+  CONVERT_ARG_HANDLE_CHECKED(JSTypedArray, sin_table, 0);
+  CONVERT_ARG_HANDLE_CHECKED(JSTypedArray, cos_table, 1);
+  CONVERT_SMI_ARG_CHECKED(samples, 2);
+  RUNTIME_ASSERT(sin_table->type() == kExternalDoubleArray);
+  RUNTIME_ASSERT(cos_table->type() == kExternalDoubleArray);
+  double* sin_buffer = reinterpret_cast<double*>(
+      JSArrayBuffer::cast(sin_table->buffer())->backing_store());
+  double* cos_buffer = reinterpret_cast<double*>(
+      JSArrayBuffer::cast(cos_table->buffer())->backing_store());
+
+  static const double pi_half = 3.1415926535897932 / 2;
+  double interval = pi_half / samples;
+  for (int i = 1; i < samples + 1; i++) {

[Jakob Kummerow, 2013/10/29 17:17:53]

i = 1? Why not i = 0?

+    double sample = sin(i * interval);
+    sin_buffer[i] = sample;
+    cos_buffer[samples - i] = sample * interval;
+  }
+
+  // Fill this to catch out of bound accesses when calculating Math.sin(pi/2).
+  sin_buffer[samples + 1] = sin(pi_half + interval);
+  cos_buffer[samples + 1] = cos(pi_half + interval) * interval;
+
+  return isolate->heap()->undefined_value();
+}
+
+
 RUNTIME_FUNCTION(MaybeObject*, Runtime_DateMakeDay) {
   SealHandleScope shs(isolate);
   ASSERT(args.length() == 2);
 
   CONVERT_SMI_ARG_CHECKED(year, 0);
   CONVERT_SMI_ARG_CHECKED(month, 1);
 
   return Smi::FromInt(isolate->date_cache()->DaysFromYearMonth(year, month));
 }
 
@@ skipping 7006 matching lines @@
     // Handle last resort GC and make sure to allow future allocations
     // to grow the heap without causing GCs (if possible).
     isolate->counters()->gc_last_resort_from_js()->Increment();
     isolate->heap()->CollectAllGarbage(Heap::kNoGCFlags,
                                        "Runtime::PerformGC");
   }
 }
 
 
 } }  // namespace v8::internal