Float int cast native code

reinterpret

julia> function fn(x1::Float64, x2::Float64)
         x1_int = reinterpret(UInt64, x1)
         x2_int = reinterpret(UInt64, x2)
         reinterpret(Float64, (x1_int + x2_int) >> 1)
       end
fn (generic function with 1 method)

julia> @code_native fn(3.0, 4.0)
	.section	__TEXT,__text,regular,pure_instructions
Filename: none
Source line: 2
	pushq	%rbp
	movq	%rsp, %rbp
Source line: 2
	movd	%xmm0, %rcx
Source line: 3
	movd	%xmm1, %rax
Source line: 4
	addq	%rcx, %rax
	shrq	%rax
	movd	%rax, %xmm0
	popq	%rbp
	ret