This is adding more validation of intrinsics. It addresses a bug in rand where CHECK-fails would occur for bad range inputs, instead of a runtime error. I'm also addressing what I think was an int32 range issue in the handling by running the generator with int64.
The intent here is that changes to prelude.carbon shouldn't break every test that expects some error from prelude.carbon; that would be too fragile. As a consequence, this effectively ignores the line number in prelude.carbon.
This is a little complex because we don't know which line in the original source file is actually causing the error, just that there is an error. Also, the previous look-behind approach required a fixed-with prefix, whereas we want a little more than that in order to capture the filename for comparison.
This would be hard to do with extra_check_replacement because the path to bazel.runfiles is complex to calculate. As a consequence, this is basically all new code.
Co-authored-by: Richard Smith <richard@metafoo.co.uk>