The current code for handling pow(x, y) where y is an integer plus 0.5 is not explicitly guarded against attempting to transform the case where abs(y) is exactly 0.5.
The latter case is meant to be handled by replacePowWithSqrt. Indeed, if the pow(x, integer+0.5) case proceeds past a certain point, it will hit an assertion by attempting to form pow(x, 0) using getPow.
This patch adds an explicit check to prevent attempting the pow(x, integer+0.5) transformation on pow(x, +/-0.5) as suggested during the review of D87877. This has the effect of retaining the shrinking of pow to powf when the sqrt libcall cannot be formed.