https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80131
--- Comment #7 from Wilco <wilco at gcc dot gnu.org> --- Author: wilco Date: Tue Nov 7 12:23:38 2017 New Revision: 254496 URL: https://gcc.gnu.org/viewcvs?rev=254496&root=gcc&view=rev Log: PR80131: Simplification of 1U << (31 - x) Currently the code A << (B - C) is not simplified. However at least a more specific case of 1U << (C -x) where C = precision(type) - 1 can be simplified to (1 << C) >> x. This is done by adding a new simplification rule in match.pd. 2017-11-07 Sudakshina Das <sudi....@arm.com> gcc/ PR middle-end/80131 * match.pd: Simplify 1 << (C - x) where C = precision (x) - 1. testsuite/ PR middle-end/80131 * testsuite/gcc.dg/pr80131-1.c: New Test. Added: trunk/gcc/testsuite/gcc.dg/pr80131-1.c Modified: trunk/gcc/ChangeLog trunk/gcc/match.pd trunk/gcc/testsuite/ChangeLog
