VM: Intrinsify double arithmetic operations with a smi rhs.

runtime/vm/intrinsifier_mips.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/globals.h"  // Needed here to get TARGET_ARCH_MIPS.
 #if defined(TARGET_ARCH_MIPS)
 
 #include "vm/intrinsifier.h"
 
 #include "vm/assembler.h"
@@ skipping 1364 matching lines @@
 
 
 void Intrinsifier::Double_lessEqualThan(Assembler* assembler) {
   CompareDoubles(assembler, LE);
 }
 
 
 // Expects left argument to be double (receiver). Right argument is unknown.
 // Both arguments are on stack.
 static void DoubleArithmeticOperations(Assembler* assembler, Token::Kind kind) {
-  Label fall_through;
+  Label fall_through, is_smi, double_op;
 
-  TestLastArgumentIsDouble(assembler, &fall_through, &fall_through);
+  TestLastArgumentIsDouble(assembler, &is_smi, &fall_through);
   // Both arguments are double, right operand is in T0.
   __ lwc1(F2, FieldAddress(T0, Double::value_offset()));
   __ lwc1(F3, FieldAddress(T0, Double::value_offset() + kWordSize));
+  __ Bind(&double_op);
   __ lw(T0, Address(SP, 1 * kWordSize));  // Left argument.
   __ lwc1(F0, FieldAddress(T0, Double::value_offset()));
   __ lwc1(F1, FieldAddress(T0, Double::value_offset() + kWordSize));
   switch (kind) {
     case Token::kADD: __ addd(D0, D0, D1); break;
     case Token::kSUB: __ subd(D0, D0, D1); break;
     case Token::kMUL: __ muld(D0, D0, D1); break;
     case Token::kDIV: __ divd(D0, D0, D1); break;
     default: UNREACHABLE();
   }
   const Class& double_class = Class::Handle(
       Isolate::Current()->object_store()->double_class());
   __ TryAllocate(double_class, &fall_through, V0, T1);  // Result register.
   __ swc1(F0, FieldAddress(V0, Double::value_offset()));
   __ Ret();
   __ delay_slot()->swc1(F1,
                         FieldAddress(V0, Double::value_offset() + kWordSize));
+
+  __ Bind(&is_smi);
+  __ SmiUntag(T0);
+  __ mtc1(T0, STMP1);
+  __ cvtdw(D1, STMP1);
+  __ b(&double_op);

[zra, 2016/03/22 17:12:21]

It looks like you can use the delay slot here.

[Florian Schneider, 2016/03/25 16:09:47]

Done. Here and for comparisons.

+
   __ Bind(&fall_through);
 }
 
 
 void Intrinsifier::Double_add(Assembler* assembler) {
   DoubleArithmeticOperations(assembler, Token::kADD);
 }
 
 
 void Intrinsifier::Double_mul(Assembler* assembler) {
@@ skipping 804 matching lines @@
 
 void Intrinsifier::Profiler_getCurrentTag(Assembler* assembler) {
   __ LoadIsolate(V0);
   __ Ret();
   __ delay_slot()->lw(V0, Address(V0, Isolate::current_tag_offset()));
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_MIPS