gh-99955: standardize return values of functions in assembler and optimizer.

[iritkatriel]

The individual commit may be easier to review.

• Issue: error handling in the compiler is inconsistent #99955

[markshannon]

Thanks for doing this.
Does this cover everything in compile.c that used the 0/1 style return?

[markshannon]

All the functions changed are static, so you can skip the news item.

[iritkatriel]

Thanks for doing this.
Does this cover everything in compile.c that used the 0/1 style return?

It doesn't cover any of the code-gen function, just optimizer and assembler.

code-gen uses 0/1, and the RETURN_IF_FALSE macro, which I think we should either do without or turn into RETURN_IF_ERROR (which would be -1).