VM: Support fast calls to atan and atan2 in optimized code.

runtime/vm/intermediate_language.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/intermediate_language.h"
 
 #include "vm/bit_vector.h"
 #include "vm/bootstrap.h"
 #include "vm/compiler.h"
 #include "vm/constant_propagator.h"
@@ skipping 3525 matching lines @@
 intptr_t InvokeMathCFunctionInstr::ArgumentCountFor(
     MethodRecognizer::Kind kind) {
   switch (kind) {
     case MethodRecognizer::kDoubleTruncate:
     case MethodRecognizer::kDoubleFloor:
     case MethodRecognizer::kDoubleCeil: {
       ASSERT(!TargetCPUFeatures::double_truncate_round_supported());
       return 1;
     }
     case MethodRecognizer::kDoubleRound:
+    case MethodRecognizer::kMathAtan:
       return 1;
     case MethodRecognizer::kDoubleMod:
     case MethodRecognizer::kMathDoublePow:
+    case MethodRecognizer::kMathAtan2:
       return 2;
     default:
       UNREACHABLE();
   }
   return 0;
 }
 
 // Use expected function signatures to help MSVC compiler resolve overloading.
 typedef double (*UnaryMathCFunction) (double x);
 typedef double (*BinaryMathCFunction) (double x, double y);
 
 DEFINE_RAW_LEAF_RUNTIME_ENTRY(LibcPow, 2, true /* is_float */,
     reinterpret_cast<RuntimeFunction>(
         static_cast<BinaryMathCFunction>(&pow)));
 
 DEFINE_RAW_LEAF_RUNTIME_ENTRY(DartModulo, 2, true /* is_float */,
     reinterpret_cast<RuntimeFunction>(
         static_cast<BinaryMathCFunction>(&DartModulo)));
 
+DEFINE_RAW_LEAF_RUNTIME_ENTRY(LibcAtan2, 2, true /* is_float */,
+    reinterpret_cast<RuntimeFunction>(
+        static_cast<BinaryMathCFunction>(&atan2)));

[Vyacheslav Egorov (Google), 2016/02/04 10:30:58]

I think this has to call to atan2_ieee to workaround some Windows specific
stuff.

[Florian Schneider, 2016/02/04 21:41:49]

Yes. Done.

+
 DEFINE_RAW_LEAF_RUNTIME_ENTRY(LibcFloor, 1, true /* is_float */,
     reinterpret_cast<RuntimeFunction>(
         static_cast<UnaryMathCFunction>(&floor)));
 
 DEFINE_RAW_LEAF_RUNTIME_ENTRY(LibcCeil, 1, true /* is_float */,
     reinterpret_cast<RuntimeFunction>(
         static_cast<UnaryMathCFunction>(&ceil)));
 
 DEFINE_RAW_LEAF_RUNTIME_ENTRY(LibcTrunc, 1, true /* is_float */,
     reinterpret_cast<RuntimeFunction>(
@@ skipping 11 matching lines @@
     case MethodRecognizer::kDoubleRound:
       return kLibcRoundRuntimeEntry;
     case MethodRecognizer::kDoubleFloor:
       return kLibcFloorRuntimeEntry;
     case MethodRecognizer::kDoubleCeil:
       return kLibcCeilRuntimeEntry;
     case MethodRecognizer::kMathDoublePow:
       return kLibcPowRuntimeEntry;
     case MethodRecognizer::kDoubleMod:
       return kDartModuloRuntimeEntry;
+    case MethodRecognizer::kMathAtan:
+      return kLibcAtanRuntimeEntry;
+    case MethodRecognizer::kMathAtan2:
+      return kLibcAtan2RuntimeEntry;
     default:
       UNREACHABLE();
   }
   return kLibcPowRuntimeEntry;
 }
 
 
 DEFINE_RAW_LEAF_RUNTIME_ENTRY(LibcCos, 1, true /* is_float */,
     reinterpret_cast<RuntimeFunction>(
         static_cast<UnaryMathCFunction>(&cos)));
 
 DEFINE_RAW_LEAF_RUNTIME_ENTRY(LibcSin, 1, true /* is_float */,
     reinterpret_cast<RuntimeFunction>(
         static_cast<UnaryMathCFunction>(&sin)));
 
+DEFINE_RAW_LEAF_RUNTIME_ENTRY(LibcAtan, 1, true /* is_float */,
+    reinterpret_cast<RuntimeFunction>(
+        static_cast<UnaryMathCFunction>(&atan)));
 
 const RuntimeEntry& MathUnaryInstr::TargetFunction() const {
   switch (kind()) {
     case MathUnaryInstr::kSin:
       return kLibcSinRuntimeEntry;
     case MathUnaryInstr::kCos:
       return kLibcCosRuntimeEntry;
     default:
       UNREACHABLE();
   }
@@ skipping 73 matching lines @@
   set_native_c_function(native_function);
   function().SetIsNativeAutoSetupScope(auto_setup_scope);
   Dart_NativeEntryResolver resolver = library.native_entry_resolver();
   bool is_bootstrap_native = Bootstrap::IsBootstapResolver(resolver);
   set_is_bootstrap_native(is_bootstrap_native);
 }
 
 #undef __
 
 }  // namespace dart