In Julia I do not need the Godbolt compiler explorer. The macros `@code_llvm` and `@code_native` show me the LLVM IR and native code for a function.

  julia> @code_llvm debuginfo=:none 5.0 + 3
  define double @"julia_+_156"(double %0, i64 signext %1) #0 
  {
  top:
    %2 = sitofp i64 %1 to double
    %3 = fadd double %2, %0
    ret double %3
  }

  julia> @code_native debuginfo=:none 5.0 + 3
  ...
    vcvtsi2sd %rdi, %xmm1, %xmm1
    vaddsd %xmm0, %xmm1, %xmm0
    retq
  ...

There's a reason Godbolt was made for C/C++ rather than python/R. In a fast language you need to know what the compiler is doing to know what's slow. In a slow language, the slow part is pretty much always just "code that does anything in the language".