Re: [09/nn] Add a fixed_size_mode_pod class

[Richard Sandiford <richard dot sandiford at linaro dot org>]

Richard Biener <richard.guenther@gmail.com> writes:
> On Mon, Oct 23, 2017 at 1:22 PM, Richard Sandiford
> <richard.sandiford@linaro.org> wrote:
>> This patch adds a POD version of fixed_size_mode.  The only current use
>> is for storing the __builtin_apply and __builtin_result register modes,
>> which were made fixed_size_modes by the previous patch.
>
> Bah - can we update our host compiler to C++11/14 please ...?
> (maybe requiring that build with GCC 4.8 as host compiler works,
> GCC 4.3 has -std=c++0x, but I'm quite sure that's not enough).

That'd be great :-)  It would avoid all the poly_int_pod stuff too,
and allow some clean-up of wide-int.h.

Thanks for the reviews,
Richard


>
> Ok.
>
> Thanks,
> Richard.
>
>>
>> 2017-10-23  Richard Sandiford  <richard.sandiford@linaro.org>
>>             Alan Hayward  <alan.hayward@arm.com>
>>             David Sherwood  <david.sherwood@arm.com>
>>
>> gcc/
>>         * coretypes.h (fixed_size_mode): Declare.
>>         (fixed_size_mode_pod): New typedef.
>>         * builtins.h (target_builtins::x_apply_args_mode)
>>         (target_builtins::x_apply_result_mode): Change type to
>>         fixed_size_mode_pod.
>>         * builtins.c (apply_args_size, apply_result_size, result_vector)
>>         (expand_builtin_apply_args_1, expand_builtin_apply)
>>         (expand_builtin_return): Update accordingly.
>>
>> Index: gcc/coretypes.h
>> ===================================================================
>> --- gcc/coretypes.h     2017-09-11 17:10:58.656085547 +0100
>> +++ gcc/coretypes.h     2017-10-23 11:42:57.592545063 +0100
>> @@ -59,6 +59,7 @@ typedef const struct rtx_def *const_rtx;
>>  class scalar_int_mode;
>>  class scalar_float_mode;
>>  class complex_mode;
>> +class fixed_size_mode;
>>  template<typename> class opt_mode;
>>  typedef opt_mode<scalar_mode> opt_scalar_mode;
>>  typedef opt_mode<scalar_int_mode> opt_scalar_int_mode;
>> @@ -66,6 +67,7 @@ typedef opt_mode<scalar_float_mode> opt_
>>  template<typename> class pod_mode;
>>  typedef pod_mode<scalar_mode> scalar_mode_pod;
>>  typedef pod_mode<scalar_int_mode> scalar_int_mode_pod;
>> +typedef pod_mode<fixed_size_mode> fixed_size_mode_pod;
>>
>>  /* Subclasses of rtx_def, using indentation to show the class
>>     hierarchy, along with the relevant invariant.
>> Index: gcc/builtins.h
>> ===================================================================
>> --- gcc/builtins.h      2017-08-30 12:18:46.602740973 +0100
>> +++ gcc/builtins.h      2017-10-23 11:42:57.592545063 +0100
>> @@ -29,14 +29,14 @@ struct target_builtins {
>>       the register is not used for calling a function.  If the machine
>>       has register windows, this gives only the outbound registers.
>>       INCOMING_REGNO gives the corresponding inbound register.  */
>> -  machine_mode x_apply_args_mode[FIRST_PSEUDO_REGISTER];
>> +  fixed_size_mode_pod x_apply_args_mode[FIRST_PSEUDO_REGISTER];
>>
>>    /* For each register that may be used for returning values, this gives
>>       a mode used to copy the register's value.  VOIDmode indicates the
>>       register is not used for returning values.  If the machine has
>>       register windows, this gives only the outbound registers.
>>       INCOMING_REGNO gives the corresponding inbound register.  */
>> -  machine_mode x_apply_result_mode[FIRST_PSEUDO_REGISTER];
>> +  fixed_size_mode_pod x_apply_result_mode[FIRST_PSEUDO_REGISTER];
>>  };
>>
>>  extern struct target_builtins default_target_builtins;
>> Index: gcc/builtins.c
>> ===================================================================
>> --- gcc/builtins.c      2017-10-23 11:41:23.140260335 +0100
>> +++ gcc/builtins.c      2017-10-23 11:42:57.592545063 +0100
>> @@ -1358,7 +1358,6 @@ apply_args_size (void)
>>    static int size = -1;
>>    int align;
>>    unsigned int regno;
>> -  machine_mode mode;
>>
>>    /* The values computed by this function never change.  */
>>    if (size < 0)
>> @@ -1374,7 +1373,7 @@ apply_args_size (void)
>>        for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
>>         if (FUNCTION_ARG_REGNO_P (regno))
>>           {
>> -           mode = targetm.calls.get_raw_arg_mode (regno);
>> +           fixed_size_mode mode = targetm.calls.get_raw_arg_mode (regno);
>>
>>             gcc_assert (mode != VOIDmode);
>>
>> @@ -1386,7 +1385,7 @@ apply_args_size (void)
>>           }
>>         else
>>           {
>> -           apply_args_mode[regno] = VOIDmode;
>> +           apply_args_mode[regno] = as_a <fixed_size_mode> (VOIDmode);
>>           }
>>      }
>>    return size;
>> @@ -1400,7 +1399,6 @@ apply_result_size (void)
>>  {
>>    static int size = -1;
>>    int align, regno;
>> -  machine_mode mode;
>>
>>    /* The values computed by this function never change.  */
>>    if (size < 0)
>> @@ -1410,7 +1408,7 @@ apply_result_size (void)
>>        for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
>>         if (targetm.calls.function_value_regno_p (regno))
>>           {
>> -           mode = targetm.calls.get_raw_result_mode (regno);
>> +           fixed_size_mode mode = targetm.calls.get_raw_result_mode (regno);
>>
>>             gcc_assert (mode != VOIDmode);
>>
>> @@ -1421,7 +1419,7 @@ apply_result_size (void)
>>             apply_result_mode[regno] = mode;
>>           }
>>         else
>> -         apply_result_mode[regno] = VOIDmode;
>> +         apply_result_mode[regno] = as_a <fixed_size_mode> (VOIDmode);
>>
>>        /* Allow targets that use untyped_call and untyped_return to override
>>          the size so that machine-specific information can be stored here.  */
>> @@ -1440,7 +1438,7 @@ apply_result_size (void)
>>  result_vector (int savep, rtx result)
>>  {
>>    int regno, size, align, nelts;
>> -  machine_mode mode;
>> +  fixed_size_mode mode;
>>    rtx reg, mem;
>>    rtx *savevec = XALLOCAVEC (rtx, FIRST_PSEUDO_REGISTER);
>>
>> @@ -1469,7 +1467,7 @@ expand_builtin_apply_args_1 (void)
>>  {
>>    rtx registers, tem;
>>    int size, align, regno;
>> -  machine_mode mode;
>> +  fixed_size_mode mode;
>>    rtx struct_incoming_value = targetm.calls.struct_value_rtx (cfun ? TREE_TYPE (cfun->decl) : 0, 1);
>>
>>    /* Create a block where the arg-pointer, structure value address,
>> @@ -1573,7 +1571,7 @@ expand_builtin_apply_args (void)
>>  expand_builtin_apply (rtx function, rtx arguments, rtx argsize)
>>  {
>>    int size, align, regno;
>> -  machine_mode mode;
>> +  fixed_size_mode mode;
>>    rtx incoming_args, result, reg, dest, src;
>>    rtx_call_insn *call_insn;
>>    rtx old_stack_level = 0;
>> @@ -1734,7 +1732,7 @@ expand_builtin_apply (rtx function, rtx
>>  expand_builtin_return (rtx result)
>>  {
>>    int size, align, regno;
>> -  machine_mode mode;
>> +  fixed_size_mode mode;
>>    rtx reg;
>>    rtx_insn *call_fusage = 0;
>>