X64: Added jmp and call and nop(n) to X64 assembler.

src/assembler.h

Index: src/assembler.h
diff --git a/src/assembler.h b/src/assembler.h
index 3449063e0077a9ca2237a9a96eae6de2800ddf01..c31704be348edd6f506bc60e500df9c6c8a6b7c0 100644
--- a/src/assembler.h
+++ b/src/assembler.h
@@ -437,6 +437,7 @@ static inline bool is_uintn(int x, int n) {
   return (x & -(1 << n)) == 0;
 }
 
+static inline bool is_uint2(int x)  { return is_uintn(x, 2); }
 static inline bool is_uint3(int x)  { return is_uintn(x, 3); }
 static inline bool is_uint4(int x)  { return is_uintn(x, 4); }
 static inline bool is_uint5(int x)  { return is_uintn(x, 5); }