middle-end/106053 - fold_sign_changed_comparison and large bools

middle-end/106053 - fold_sign_changed_comparison and large bools

The following fixes a latent issue in the match.pd variant of
fold_sign_changed_comparison which replaces an unsigned integer
comparison with a signed boolean comparison of the same precision
despite the fact that we treat BOOLEAN_TYPEs as only having two
valid values.

2022-06-28  Richard Biener  <rguenther@suse.de>

	PR middle-end/106053
	* match.pd ((T)a == (T)b): Avoid folding away sign
	changes in a comparison if we'd truncate to a boolean.

	* gcc.target/i386/pr106053.c: New testcase.