This is awkward because I'm mansplaining your own project back to you, but, as I understand it, you were compiling to the 68(HC?)11, which your CL compiler back end didn't support, so I don't think it helped you in that way, to generate the final code. Unless I've misunderstood something fundamental?
Depending on how the compiler was structured, it could have helped you in some other way, like doing target-independent optimizations, if there was a way to get some kind of IR out of it instead of native code for the wrong CPU.
I agree that there are lots of cases where the approach you're describing works very well and has a huge payoff, though I've only done it with C, JS, and Lua compilers rather than CL compilers. Usually it's been more like 20% of the work rather than 1% of the work, but maybe that depends on the level of optimization you're hoping for.
Depending on how the compiler was structured, it could have helped you in some other way, like doing target-independent optimizations, if there was a way to get some kind of IR out of it instead of native code for the wrong CPU.
I agree that there are lots of cases where the approach you're describing works very well and has a huge payoff, though I've only done it with C, JS, and Lua compilers rather than CL compilers. Usually it's been more like 20% of the work rather than 1% of the work, but maybe that depends on the level of optimization you're hoping for.