https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97715
--- Comment #21 from Qing Zhao <qing.zhao at oracle dot com> --- > --- Comment #19 from Jakub Jelinek <jakub at gcc dot gnu.org> --- > And, actually the function.c change is probably unnecessary, because the > if (!crtl->abi->clobbers_full_reg_p (regno)) > continue; > if (!fixed_regs[i]) > continue; > should already rule them out. > operand_reg_set &= accessible_reg_set; > ... > /* If a register is too limited to be treated as a register operand, > then it should never be allocated to a pseudo. */ > if (!TEST_HARD_REG_BIT (operand_reg_set, i)) > fixed_regs[i] = 1; So, fixed_regs should already include the information of accessible_reg_set, no need to check accessible_reg_set anymore.