Exception for fabs fraction 1

Math

\[\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right|\]

C

double f(double x, double y, double z) {
        double r41771 = x;
        double r41772 = 4.0;
        double r41773 = r41771 + r41772;
        double r41774 = y;
        double r41775 = r41773 / r41774;
        double r41776 = r41771 / r41774;
        double r41777 = z;
        double r41778 = r41776 * r41777;
        double r41779 = r41775 - r41778;
        double r41780 = fabs(r41779);
        return r41780;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019323 +o rules:numerics
(FPCore (x y z)
  :name "fabs fraction 1"
  :precision binary64
  (fabs (- (/ (+ x 4) y) (* (/ x y) z))))

Backtrace

dict-ref: no value for key: 'branch41770 in: '((x . binary64) (y . binary64) (z . binary64))		L	C
for-loop	/data/pavpan/nightlies/herbie/fix-interface-bugs/src/points.rkt	106	4
make-sampler	/data/pavpan/nightlies/herbie/fix-interface-bugs/src/points.rkt	99	0
prepare-points-intervals	/data/pavpan/nightlies/herbie/fix-interface-bugs/src/points.rkt	121	0
for-loop	/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/regimes.rkt	233	9
sindices->spoints	/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/regimes.rkt	194	0
f33	/opt/racket-7.2/collects/racket/match/compiler.rkt	507	40
get-final-combination	/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt	369	0
(unnamed)	/opt/racket-7.2/collects/racket/private/more-scheme.rkt	261	28
run	/opt/racket-7.2/share/pkgs/profile-lib/main.rkt	39	2
profile-thunk16	/opt/racket-7.2/share/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/opt/racket-7.2/collects/racket/private/more-scheme.rkt	261	28