Hans-Peter Nilsson <h...@bitrange.com> writes: > On Thu, 13 Mar 2025, Konstantinos Eleftheriou wrote: >> Testcases for match.pd patterns >> `((a ^ b) & c) cmp d | a != b -> (0 cmp d | a != b)` and >> `(a ^ b) cmp c | a != b -> (0 cmp c | a != b)` were failing on some targets, >> like PowerPC. >> >> This patch adds an implemenetation for the optimization in reassoc. Doing so, >> we can now handle cases where the related conditions appear in an AND >> expression too. Also, we can optimize cases where we have intermediate >> expressions between the related ones in the AND/OR expression on some >> targets. >> This is not handled on targets like PowerPC, where each condition of the >> AND/OR expression is placed into a different basic block. >> >> Bootstrapped/regtested on x86 and AArch64. >> >> PR tree-optimization/116860 >> >> gcc/ChangeLog: >> >> * tree-ssa-reassoc.cc (solve_expr): New function. >> (find_terminal_nodes): New function. >> (get_terminal_nodes): New function. >> (optimize_cmp_xor_exprs): New function. >> (optimize_range_tests): Call optimize_cmp_xor_exprs. >> >> gcc/testsuite/ChangeLog: >> >> * gcc.dg/tree-ssa/fold-xor-and-or.c: Renamed to fold-xor-and-or-1.c. >> * gcc.dg/tree-ssa/fold-xor-and-or-1.c: >> Add new test cases, remove logical-op-non-short-circuit=1. >> * gcc.dg/tree-ssa/fold-xor-or.c: Likewise. >> * gcc.dg/tree-ssa/fold-xor-and-or-2.c: New test. > > Sniping from the sideline, sorry: > > Please don't modify existing tests, just add new tests (in new > files) unless there's something wrong with the existing test. > > > (I.e. dropping --param logical-op-non-short-circuit=1 is fine if > you fixed the general case, but adding or removing code or > renaming the test, isn't.)
Right (see r15-7281-g15dba7dfba8b78 wrt --param ...) but the rest of it should go into separate tests.
