This is an improved version of a fix I previously contributed to Sledgehammer. It now uses ASM and works even when OptiFine is installed. I also rewrote it to use local variables instead of allocating at least two AxisAlignedBB objects per entity every time the method is called.
Make BlockModelRendererMixin work with OptiFine
OptiFine's version of this method has a different LVT so I used a redirect instead.
AxisAlignedBBobjects per entity every time the method is called.