No subject

(
(declare (temporary ) float light_y)
(declare (out ) vec4 gl_FragColor)
(function main
  (signature void
    (parameters
    )
    (
      (assign  (x) (var_ref gl_FragColor)  (expression float * (constant
float (0.900000)) (var_ref light_y) ) ) 
      (assign  (y) (var_ref gl_FragColor)  (expression float * (constant
float (0.900000)) (var_ref light_y) ) ) 
      (assign  (z) (var_ref gl_FragColor)  (expression float * (constant
float (0.900000)) (var_ref light_y) ) ) 
      (assign  (w) (var_ref gl_FragColor)  (var_ref light_y) ) 
    ))

)
)

I don't claim to understand how (obviously there's no ir_binop_dot in
opt_algebraic.cpp, so) but it looks like we're already getting the
result of the TODO.

The other part that I thought opt_algebraic.cpp's ir_binop_dot case
should handle was zero vectors, but they're already handled as well. I
presume because dot is lowered into mul/madd which already handle zero
vectors.

Does this sound right, or did I miss some piece?

Thanks,
Matt