\[x - \frac{y - z}{\frac{\left(t - z\right) + 1}{a}}\]
x - \frac{y - z}{\frac{\left(t - z\right) + 1}{a}}
double f(double x, double y, double z, double t, double a) {
        double r279357893 = x;
        double r279357894 = y;
        double r279357895 = z;
        double r279357896 = r279357894 - r279357895;
        double r279357897 = t;
        double r279357898 = r279357897 - r279357895;
        double r279357899 = 1.0;
        double r279357900 = r279357898 + r279357899;
        double r279357901 = a;
        double r279357902 = r279357900 / r279357901;
        double r279357903 = r279357896 / r279357902;
        double r279357904 = r279357893 - r279357903;
        return r279357904;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019173 
(FPCore (x y z t a)
  :name "Graphics.Rendering.Chart.SparkLine:renderSparkLine from Chart-1.5.3"

  :herbie-target
  (- x (* (/ (- y z) (+ (- t z) 1.0)) a))

  (- x (/ (- y z) (/ (+ (- t z) 1.0) a))))

Backtrace

hash-ref: no value found for key key: #<enode 528(528)>LC
for-loop/data/pavpan/nightlies/herbie/various-cleanup/src/core/simplify.rkt1972
extractor-extract/data/pavpan/nightlies/herbie/various-cleanup/src/core/simplify.rkt1960
for-loop/data/pavpan/nightlies/herbie/various-cleanup/src/core/simplify.rkt352
(unnamed)/data/pavpan/nightlies/herbie/various-cleanup/src/core/simplify.rkt260
simplify!/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt2170
run-iter!/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt3200
for-loop/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt3544
run-improve43/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt3390
(unnamed)/opt/racket-7.0/collects/racket/private/more-scheme.rkt26128
run/opt/racket-7.0/share/pkgs/profile-lib/main.rkt392
profile-thunk16/opt/racket-7.0/share/pkgs/profile-lib/main.rkt90
(unnamed)/opt/racket-7.0/collects/racket/private/more-scheme.rkt26128