Introduce intrinsics for double values in Javascript.

src/arm/lithium-arm.h

Index: src/arm/lithium-arm.h
diff --git a/src/arm/lithium-arm.h b/src/arm/lithium-arm.h
index b83ca134de431800382f2a90bf170b8fbbae689d..3ea86447ab85a2f25c0d1fbee3b36262ac1c2fa0 100644
--- a/src/arm/lithium-arm.h
+++ b/src/arm/lithium-arm.h
@@ -80,12 +80,14 @@ class LCodeGen;
   V(ConstantI)                                  \
   V(ConstantS)                                  \
   V(ConstantT)                                  \
+  V(ConstructDouble)                            \
   V(Context)                                    \
   V(DateField)                                  \
   V(DebugBreak)                                 \
   V(DeclareGlobals)                             \
   V(Deoptimize)                                 \
   V(DivI)                                       \
+  V(DoubleBits)                                 \
   V(DoubleToI)                                  \
   V(DoubleToSmi)                                \
   V(Drop)                                       \
@@ -2386,6 +2388,33 @@ class LClampTToUint8 V8_FINAL : public LTemplateInstruction<1, 1, 1> {
 };
 
 
+class LDoubleBits V8_FINAL : public LTemplateInstruction<1, 1, 0> {
+ public:
+  explicit LDoubleBits(LOperand* value) {
+    inputs_[0] = value;
+  }
+
+  LOperand* value() { return inputs_[0]; }
+
+  DECLARE_CONCRETE_INSTRUCTION(DoubleBits, "double-bits")
+  DECLARE_HYDROGEN_ACCESSOR(DoubleBits)
+};
+
+
+class LConstructDouble V8_FINAL : public LTemplateInstruction<1, 2, 0> {
+ public:
+  LConstructDouble(LOperand* hi, LOperand* lo) {
+    inputs_[0] = hi;
+    inputs_[1] = lo;
+  }
+
+  LOperand* hi() { return inputs_[0]; }
+  LOperand* lo() { return inputs_[1]; }
+
+  DECLARE_CONCRETE_INSTRUCTION(ConstructDouble, "construct-double")
+};
+
+
 class LAllocate V8_FINAL : public LTemplateInstruction<1, 2, 2> {
  public:
   LAllocate(LOperand* context,