live_case_bndr = not (isDeadBinder case_bndr)
env1 | Var v <- scrut = extendValEnv env v cval
| otherwise = env -- See Note [Add scrutinee to ValueEnv too]
- env2 | live_case_bndr = extendValEnv env case_bndr cval
+ env2 | live_case_bndr = extendValEnv env1 case_bndr cval
| otherwise = env1
alt_bndrs' | case scrut of { Var {} -> True; _ -> live_case_bndr }