Reland "Add DoubleTestOp instruction"

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 1512 matching lines @@
   __ cund(D0, D0);  // Check for NaN.
   __ bc1t(&is_true);
   __ LoadObject(V0, Bool::False());  // Return false if either is NaN.
   __ Ret();
   __ Bind(&is_true);
   __ LoadObject(V0, Bool::True());
   __ Ret();
 }
 
 
+void Intrinsifier::Double_getIsInfinite(Assembler* assembler) {
+  Label not_inf;
+  __ lw(T0, Address(SP, 0 * kWordSize));
+  __ lw(T1, FieldAddress(T0, Double::value_offset()));
+  __ lw(T2, FieldAddress(T0, Double::value_offset() + kWordSize));
+  // If the low word isn't zero, then it isn't infinity.
+  __ bne(T1, ZR, &not_inf);
+  // Mask off the sign bit.
+  __ AndImmediate(T2, T2, 0x7FFFFFFF);
+  // Compare with +infinity.
+  __ BranchNotEqual(T2, Immediate(0x7FF00000), &not_inf);
+
+  __ LoadObject(V0, Bool::True());
+  __ Ret();
+
+  __ Bind(&not_inf);
+  __ LoadObject(V0, Bool::False());
+  __ Ret();
+}
+
+
 void Intrinsifier::Double_getIsNegative(Assembler* assembler) {
   Label is_false, is_true, is_zero;
   __ lw(T0, Address(SP, 0 * kWordSize));
   __ LoadDFromOffset(D0, T0, Double::value_offset() - kHeapObjectTag);
 
   __ cund(D0, D0);
   __ bc1t(&is_false);  // NaN -> false.
 
   __ LoadImmediate(D1, 0.0);
   __ ceqd(D0, D1);
@@ skipping 694 matching lines @@
   __ lw(T0, Address(V0, TimelineStream::enabled_offset()));
   __ LoadObject(V0, Bool::True());
   __ LoadObject(V1, Bool::False());
   __ Ret();
   __ delay_slot()->movz(V0, V1, T0);  // V0 = (T0 == 0) ? V1 : V0.
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_MIPS