mirror of
https://github.com/gcc-mirror/gcc.git
synced 2026-05-06 14:59:39 +02:00
7ab0126939
My relatively recent changes to these simplifiers to avoid doing build_nonstandard_integer_type (primarily for BITINT_TYPE) broke PR111668, a recurrence of the PR110487 bug. I thought the build_nonstandard_integer_type isn't ever needed there, but there is one special case where it is. For the a ? -1 : 0 and a ? 0 : -1 simplifications there are actually 3 different cases. One is for signed 1-bit precision types (signed kind of implied from integer_all_onesp, because otherwise it would match integer_onep earlier), where the simplifier wierdly was matching them using the a ? powerof2cst : 0 -> a << (log2(powerof2cst)) simplification and then another simplifier optimizing away the left shift when log2(powerof2cst) was 0. Another one is signed BOOLEAN_TYPE with precision > 1, where indeed we shouldn't be doing the negation in type, because it isn't well defined in that type, the type only has 2 valid values, 0 and -1. As an alternative, we could also e.g. cast to signed 1-bit precision BOOLEAN_TYPE and then extend to type. And the last case is what we were doing for types which have both 1 and -1 (all all ones) as valid values (i.e. all signed/unsigned ENUMERAL_TYPEs, INTEGRAL_TYPEs and BITINT_TYPEs with precision > 1). The following patch avoids the hops through << 0 for 1-bit precision and uses build_nonstandard_integer_type solely for the BOOLEAN_TYPE types (where we have a guarantee the precision is reasonably small, nothing ought to be created 129+ bit precision BOOLEAN_TYPEs). 2023-10-04 Jakub Jelinek <jakub@redhat.com> PR tree-optimization/111668 * match.pd (a ? CST1 : CST2): Handle the a ? -1 : 0 and a ? 0 : -1 cases before the powerof2cst cases and differentiate between 1-bit precision types, larger precision boolean types and other integral types. Fix comment pastos and formatting.
This directory contains the GNU Compiler Collection (GCC). The GNU Compiler Collection is free software. See the files whose names start with COPYING for copying permission. The manuals, and some of the runtime libraries, are under different terms; see the individual source files for details. The directory INSTALL contains copies of the installation information as HTML and plain text. The source of this information is gcc/doc/install.texi. The installation information includes details of what is included in the GCC sources and what files GCC installs. See the file gcc/doc/gcc.texi (together with other files that it includes) for usage and porting information. An online readable version of the manual is in the files gcc/doc/gcc.info*. See http://gcc.gnu.org/bugs/ for how to report bugs usefully. Copyright years on GCC source files may be listed using range notation, e.g., 1987-2012, indicating that every year in the range, inclusive, is a copyrightable year that could otherwise be listed individually.