@code_typed: positiveReal^realExponent

New to Julia
1

Hi, using @code_typed in the code below, shows that julia checks for the sign of a number X when raised to the power of a real number (pow function). is it possible to avoid this if X is positive X=abs(…)?
code:
cTime+(abs(q[i]/df))^(1/3)
@code_typed:

%25 = Base.abs_float(%24)::Float64
│    %26 = $(Expr(:foreigncall, "llvm.pow.f64", Float64, svec(Float64, Float64), 0, :(:llvmcall), :(%25), 0.3333333333333333, 0.3333333333333333, :(%25)))::Float64
│    %27 = Base.ne_float(%26, %26)::Bool
│    %28 = Base.add_float(%25, 0.3333333333333333)::Float64
│    %29 = Base.ne_float(%28, %28)::Bool
│    %30 = Base.not_int(%29)::Bool
│    %31 = Base.and_int(%27, %30)::Bool
└───       goto #7 if not %31
6 ──       invoke Base.Math.throw_exp_domainerror(%25::Float64)::Union{}
└───       unreachable

thanks

2

In general, the compiler can’t specialize on the value of the function, only the type…

However, in the particular case of x^(1/3) you should call the cbrt function rather than using generic exponentiation.