Push safepoint registers in deferred number-to-i/u only on-demand.

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 fbe52644ad4d1c9a9356a2f04ed8de38f7134acc..b83ca134de431800382f2a90bf170b8fbbae689d 100644
--- a/src/arm/lithium-arm.h
+++ b/src/arm/lithium-arm.h
@@ -1936,25 +1936,33 @@ class LUint32ToSmi V8_FINAL : public LTemplateInstruction<1, 1, 0> {
 };
 
 
-class LNumberTagI V8_FINAL : public LTemplateInstruction<1, 1, 0> {
+class LNumberTagI V8_FINAL : public LTemplateInstruction<1, 1, 2> {
  public:
-  explicit LNumberTagI(LOperand* value) {
+  LNumberTagI(LOperand* value, LOperand* temp1, LOperand* temp2) {
     inputs_[0] = value;
+    temps_[0] = temp1;
+    temps_[1] = temp2;
   }
 
   LOperand* value() { return inputs_[0]; }
+  LOperand* temp1() { return temps_[0]; }
+  LOperand* temp2() { return temps_[1]; }
 
   DECLARE_CONCRETE_INSTRUCTION(NumberTagI, "number-tag-i")
 };
 
 
-class LNumberTagU V8_FINAL : public LTemplateInstruction<1, 1, 0> {
+class LNumberTagU V8_FINAL : public LTemplateInstruction<1, 1, 2> {
  public:
-  explicit LNumberTagU(LOperand* value) {
+  LNumberTagU(LOperand* value, LOperand* temp1, LOperand* temp2) {
     inputs_[0] = value;
+    temps_[0] = temp1;
+    temps_[1] = temp2;
   }
 
   LOperand* value() { return inputs_[0]; }
+  LOperand* temp1() { return temps_[0]; }
+  LOperand* temp2() { return temps_[1]; }
 
   DECLARE_CONCRETE_INSTRUCTION(NumberTagU, "number-tag-u")
 };