On 07/13/2017 02:40 AM, Richard Sandiford wrote: > GET_MODE_WIDER previously returned VOIDmode if no wider mode existed. > That would cause problems with stricter mode classes, since VOIDmode > isn't for example a valid scalar integer or floating-point mode. > This patch instead makes it return a new opt_mode<T> class, which > holds either a T or nothing. > > 2017-07-13 Richard Sandiford <richard.sandif...@linaro.org> > Alan Hayward <alan.hayw...@arm.com> > David Sherwood <david.sherw...@arm.com> > > gcc/ > * coretypes.h (opt_mode): New class. > * machmode.h (opt_mode): Likewise. > (opt_mode::else_void): New function. > (opt_mode::operator *): Likewise. > (opt_mode::exists): Likewise. > (GET_MODE_WIDER_MODE): Turn into a function and return an opt_mode. > (GET_MODE_2XWIDER_MODE): Likewise. > (mode_iterator::get_wider): Update accordingly. > (mode_iterator::get_2xwider): Likewise. > (mode_iterator::get_known_wider): Likewise, turning into a template. > * combine.c (make_extraction): Update use of GET_MODE_WIDER_MODE, > forcing a wider mode to exist. > * config/cr16/cr16.h (LONG_REG_P): Likewise. > * rtlanal.c (init_num_sign_bit_copies_in_rep): Likewise. > * config/c6x/c6x.c (c6x_rtx_costs): Update use of > GET_MODE_2XWIDER_MODE, forcing a wider mode to exist. > * lower-subreg.c (init_lower_subreg): Likewise. > * optabs-libfuncs.c (init_sync_libfuncs_1): Likewise, but not > on the final iteration. > * config/i386/i386.c (ix86_expand_set_or_movmem): Check whether > a wider mode exists before asking for a move pattern. > (get_mode_wider_vector): Update use of GET_MODE_WIDER_MODE, > forcing a wider mode to exist. > (expand_vselect_vconcat): Update use of GET_MODE_2XWIDER_MODE, > returning false if no such mode exists. > * config/ia64/ia64.c (expand_vselect_vconcat): Likewise. > * config/mips/mips.c (mips_expand_vselect_vconcat): Likewise. > * expmed.c (init_expmed_one_mode): Update use of GET_MODE_WIDER_MODE. > Avoid checking for a MODE_INT if we already know the mode is not a > SCALAR_INT_MODE_P. > (extract_high_half): Update use of GET_MODE_WIDER_MODE, > forcing a wider mode to exist. > (expmed_mult_highpart_optab): Likewise. > (expmed_mult_highpart): Likewise. > * expr.c (expand_expr_real_2): Update use of GET_MODE_WIDER_MODE, > using else_void. > * lto-streamer-in.c (lto_input_mode_table): Likewise. > * optabs-query.c (find_widening_optab_handler_and_mode): Likewise. > * stor-layout.c (bit_field_mode_iterator::next_mode): Likewise. > * internal-fn.c (expand_mul_overflow): Update use of > GET_MODE_2XWIDER_MODE. > * omp-low.c (omp_clause_aligned_alignment): Likewise. > * tree-ssa-math-opts.c (convert_mult_to_widen): Update use of > GET_MODE_WIDER_MODE. > (convert_plusminus_to_widen): Likewise. > * tree-switch-conversion.c (array_value_type): Likewise. > * var-tracking.c (emit_note_insn_var_location): Likewise. > * tree-vrp.c (simplify_float_conversion_using_ranges): Likewise. > Return false inside rather than outside the loop if no wider mode > exists > * optabs.c (expand_binop): Update use of GET_MODE_WIDER_MODE > and GET_MODE_2XWIDER_MODE > (can_compare_p): Use else_void. > * gdbhooks.py (OptMachineModePrinter): New class. > (build_pretty_printer): Use it for opt_mode. > > gcc/ada/ > * gcc-interface/decl.c (validate_size): Update use of > GET_MODE_WIDER_MODE, forcing a wider mode to exist. I'm not a big fan of the API here, particularly using operator* to handle asserting the mode exists. I'd prefer to just use a member function rather than overloading operator*.
What's the rationale behind using operator* to imply the assertion? THe changes themsleves look fine, it's really just a question of the API we present. jeff
