https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113567
--- Comment #5 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:baa40971d1600672f3a1abf688905a70cf655c92 commit r14-8995-gbaa40971d1600672f3a1abf688905a70cf655c92 Author: Jakub Jelinek <ja...@redhat.com> Date: Thu Feb 15 09:52:47 2024 +0100 lower-bitint: Ensure we don't get coalescing ICEs for (ab) SSA_NAMEs used in mul/div/mod [PR113567] The build_bitint_stmt_ssa_conflicts hook has a special case for multiplication, division and modulo, where to ensure there is no overlap between lhs and rhs1/rhs2 arrays we make the lhs conflict with the operands. On the following testcase, we have # a_1(ab) = PHI <a_2(D)(0), a_3(ab)(3)> lab: a_3(ab) = a_1(ab) % 3; before lowering and this special case causes a_3(ab) and a_1(ab) to conflict, but the PHI requires them not to conflict, so we ICE because we can't find some partitioning that will work. The following patch fixes this by special casing such statements before the partitioning, force the inputs of the multiplication/division which have large/huge _BitInt (ab) lhs into new non-(ab) SSA_NAMEs initialized right before the multiplication/division. This allows the partitioning to work then, as it has the possibility to use a different partition for the */% operands. 2024-02-15 Jakub Jelinek <ja...@redhat.com> PR tree-optimization/113567 * gimple-lower-bitint.cc (gimple_lower_bitint): For large/huge _BitInt multiplication, division or modulo with SSA_NAME_OCCURS_IN_ABNORMAL_PHI lhs and at least one of rhs1 and rhs2 force the affected inputs into a new SSA_NAME. * gcc.dg/bitint-90.c: New test.
