On Sat, Nov 18, 2023 at 8:38 PM Jakub Jelinek <ja...@redhat.com> wrote:
>
> Hi!
>
> Another obstackle mentioned in the
> https://sourceware.org/pipermail/libc-alpha/2023-November/152819.html
> thread is that half of the stdc_{leading,trailing}_{zeros,ones},
> stdc_first_{leading,trailing}_{zero,one} and stdc_count_{zeros,ones}
> type-generic macros actually need to use the __builtin_*g type-generic
> builtins on inverted values, but need to use
> (__typeof (value)) ~(value)
> for that, because if value has unsigned char or unsigned short type,
> it is promoted to int with the ~ operator, but that suffers from the
> nested macros problem as well.
>
> The following patch adds a C only builtin (if we'd want to make
> stdbit.h work in C++, I think best would be to use a function template),
> especially because the builtin needs a type-generic return type,
> which is functionally equivalent to (__typeof (arg)) ~(arg).
>
> Ok for trunk if it passes bootstrap/regtest?
And for this I suppose a "not promoting 'auto'" might be more generally
useful? So
_Unprom_auto tem = arg;
(__typeof (tem))~tem;
then?
>
> 2023-11-18 Jakub Jelinek <ja...@redhat.com>
>
> gcc/
> * doc/extend.texi (__builtin_bit_complement): Document.
> gcc/c-family/
> * c-common.h (enum rid): Add RID_BUILTIN_BIT_COMPLEMENT.
> * c-common.cc (c_common_reswords): Add __builtin_bit_complement.
> Move __builtin_assoc_barrier alphabetically.
> gcc/c/
> * c-parser.cc (c_parser_postfix_expression): Handle
> RID_BUILTIN_BIT_COMPLEMENT.
> * c-decl.cc (names_builtin_p): Likewise. Move
> RID_BUILTIN_ASSOC_BARRIER alphabetically.
> gcc/testsuite/
> * gcc.dg/builtin-bit-complement-1.c: New test.
> * gcc.dg/builtin-bit-complement-2.c: New test.
>
> --- gcc/doc/extend.texi.jj 2023-11-18 13:17:40.982551766 +0100
> +++ gcc/doc/extend.texi 2023-11-18 18:39:24.303561182 +0100
> @@ -15066,6 +15066,14 @@ unsigned integer (standard, extended or
> promotions are performed on the argument.
> @enddefbuiltin
>
> +@defbuiltin{@var{type} __builtin_bit_complement (@var{type} @var{arg})}
> +The @code{__builtin_bit_complement} function is available only
> +in C. It is type-generic, the argument can be any integral type, and
> +is equivalent to @code{(__typeof (@var{arg})) ~(@var{arg})}, except that
> +there is no need to specify the argument tokens twice. No integral argument
> +promotions are performed on the argument.
> +@enddefbuiltin
> +
> @defbuiltin{double __builtin_powi (double, int)}
> @defbuiltinx{float __builtin_powif (float, int)}
> @defbuiltinx{{long double} __builtin_powil (long double, int)}
> --- gcc/c-family/c-common.h.jj 2023-11-09 09:04:18.422546151 +0100
> +++ gcc/c-family/c-common.h 2023-11-18 17:05:00.223049400 +0100
> @@ -110,6 +110,7 @@ enum rid
> RID_TYPES_COMPATIBLE_P, RID_BUILTIN_COMPLEX,
> RID_BUILTIN_SHUFFLE,
> RID_BUILTIN_SHUFFLEVECTOR, RID_BUILTIN_CONVERTVECTOR,
> RID_BUILTIN_TGMATH,
> RID_BUILTIN_HAS_ATTRIBUTE, RID_BUILTIN_ASSOC_BARRIER,
> + RID_BUILTIN_BIT_COMPLEMENT,
> RID_DFLOAT32, RID_DFLOAT64, RID_DFLOAT128,
>
> /* TS 18661-3 keywords, in the same sequence as the TI_* values. */
> --- gcc/c-family/c-common.cc.jj 2023-11-18 13:20:55.751844490 +0100
> +++ gcc/c-family/c-common.cc 2023-11-18 17:03:17.838466559 +0100
> @@ -380,7 +380,9 @@ const struct c_common_resword c_common_r
> { "__attribute__", RID_ATTRIBUTE, 0 },
> { "__auto_type", RID_AUTO_TYPE, D_CONLY },
> { "__builtin_addressof", RID_ADDRESSOF, D_CXXONLY },
> + { "__builtin_assoc_barrier", RID_BUILTIN_ASSOC_BARRIER, 0 },
> { "__builtin_bit_cast", RID_BUILTIN_BIT_CAST, D_CXXONLY },
> + { "__builtin_bit_complement", RID_BUILTIN_BIT_COMPLEMENT, D_CONLY },
> { "__builtin_call_with_static_chain",
> RID_BUILTIN_CALL_WITH_STATIC_CHAIN, D_CONLY },
> { "__builtin_choose_expr", RID_CHOOSE_EXPR, D_CONLY },
> @@ -388,7 +390,6 @@ const struct c_common_resword c_common_r
> { "__builtin_convertvector", RID_BUILTIN_CONVERTVECTOR, 0 },
> { "__builtin_has_attribute", RID_BUILTIN_HAS_ATTRIBUTE, 0 },
> { "__builtin_launder", RID_BUILTIN_LAUNDER, D_CXXONLY },
> - { "__builtin_assoc_barrier", RID_BUILTIN_ASSOC_BARRIER, 0 },
> { "__builtin_shuffle", RID_BUILTIN_SHUFFLE, 0 },
> { "__builtin_shufflevector", RID_BUILTIN_SHUFFLEVECTOR, 0 },
> { "__builtin_tgmath", RID_BUILTIN_TGMATH, D_CONLY },
> --- gcc/c/c-parser.cc.jj 2023-11-11 08:51:54.324206082 +0100
> +++ gcc/c/c-parser.cc 2023-11-18 17:16:23.228591823 +0100
> @@ -11743,6 +11743,46 @@ c_parser_postfix_expression (c_parser *p
> set_c_expr_source_range (&expr, start_loc, end_loc);
> }
> break;
> + case RID_BUILTIN_BIT_COMPLEMENT:
> + {
> + vec<c_expr_t, va_gc> *cexpr_list;
> + c_expr_t *arg_p;
> + location_t close_paren_loc;
> +
> + c_parser_consume_token (parser);
> + if (!c_parser_get_builtin_args (parser,
> + "__builtin_bit_complement",
> + &cexpr_list, false,
> + &close_paren_loc))
> + {
> + expr.set_error ();
> + break;
> + }
> +
> + if (vec_safe_length (cexpr_list) != 1)
> + {
> + error_at (loc, "wrong number of arguments to "
> + "%<__builtin_bit_complement%>");
> + expr.set_error ();
> + break;
> + }
> +
> + arg_p = &(*cexpr_list)[0];
> + *arg_p = convert_lvalue_to_rvalue (loc, *arg_p, true, true);
> + if (!INTEGRAL_TYPE_P (TREE_TYPE (arg_p->value)))
> + {
> + error_at (loc, "%<__builtin_bit_complement%> operand "
> + "not an integral type");
> + expr.set_error ();
> + break;
> + }
> + expr.value
> + = build1_loc (loc, BIT_NOT_EXPR,
> + TYPE_MAIN_VARIANT (TREE_TYPE (arg_p->value)),
> + arg_p->value);
> + set_c_expr_source_range (&expr, loc, close_paren_loc);
> + break;
> + }
> case RID_AT_SELECTOR:
> {
> gcc_assert (c_dialect_objc ());
> --- gcc/c/c-decl.cc.jj 2023-11-09 09:04:18.463545570 +0100
> +++ gcc/c/c-decl.cc 2023-11-18 17:31:39.298880201 +0100
> @@ -11370,11 +11370,12 @@ names_builtin_p (const char *name)
> functions. */
> switch (C_RID_CODE (id))
> {
> + case RID_BUILTIN_ASSOC_BARRIER:
> + case RID_BUILTIN_BIT_COMPLEMENT:
> case RID_BUILTIN_CONVERTVECTOR:
> case RID_BUILTIN_HAS_ATTRIBUTE:
> case RID_BUILTIN_SHUFFLE:
> case RID_BUILTIN_SHUFFLEVECTOR:
> - case RID_BUILTIN_ASSOC_BARRIER:
> case RID_CHOOSE_EXPR:
> case RID_OFFSETOF:
> case RID_TYPES_COMPATIBLE_P:
> --- gcc/testsuite/gcc.dg/builtin-bit-complement-1.c.jj 2023-11-18
> 17:39:47.748104287 +0100
> +++ gcc/testsuite/gcc.dg/builtin-bit-complement-1.c 2023-11-18
> 18:33:08.700744489 +0100
> @@ -0,0 +1,87 @@
> +/* { dg-do run } */
> +/* { dg-options "-std=c11" } */
> +
> +#define expr_has_type(e, t) _Generic (e, default : 0, t : 1)
> +enum E { E0, E1 };
> +
> +int
> +main ()
> +{
> + if (__builtin_bit_complement ((unsigned char) 0) != (unsigned char)
> ~(unsigned char) 0
> + || __builtin_bit_complement ((unsigned char) 0x33) != (unsigned char)
> ~(unsigned char) 0x33
> + || !expr_has_type (__builtin_bit_complement ((unsigned char) 0),
> unsigned char)
> + || __builtin_bit_complement ((unsigned short) 0) != (unsigned short)
> ~(unsigned short) 0
> + || __builtin_bit_complement ((unsigned short) 0x5555) != (unsigned
> short) ~(unsigned short) 0x5555
> + || !expr_has_type (__builtin_bit_complement ((unsigned short) 0),
> unsigned short)
> + || __builtin_bit_complement (0U) != ~0U
> + || __builtin_bit_complement (0xaaaaU) != ~0xaaaaU
> + || !expr_has_type (__builtin_bit_complement (0U), unsigned int)
> + || __builtin_bit_complement (0UL) != ~0UL
> + || __builtin_bit_complement (0xaaaaaaaaUL) != ~0xaaaaaaaaUL
> + || !expr_has_type (__builtin_bit_complement (0UL), unsigned long)
> + || __builtin_bit_complement (0ULL) != ~0ULL
> + || __builtin_bit_complement (0xaaaaaaaa55555555ULL) !=
> ~0xaaaaaaaa55555555ULL
> + || !expr_has_type (__builtin_bit_complement (0ULL), unsigned long long)
> + || __builtin_bit_complement ((signed char) 0) != (signed char)
> ~(signed char) 0
> + || __builtin_bit_complement ((signed char) 0x33) != (signed char)
> ~(signed char) 0x33
> + || !expr_has_type (__builtin_bit_complement ((signed char) 0), signed
> char)
> + || __builtin_bit_complement ((signed short) 0) != (signed short)
> ~(signed short) 0
> + || __builtin_bit_complement ((signed short) 0x5555) != (signed short)
> ~(signed short) 0x5555
> + || !expr_has_type (__builtin_bit_complement ((signed short) 0), signed
> short)
> + || __builtin_bit_complement (0) != ~0
> + || __builtin_bit_complement (0x5aaa) != ~0x5aaa
> + || !expr_has_type (__builtin_bit_complement (0), signed int)
> + || __builtin_bit_complement (0L) != ~0L
> + || __builtin_bit_complement (0x5aaaaaaaL) != ~0x5aaaaaaaL
> + || !expr_has_type (__builtin_bit_complement (0L), signed long)
> + || __builtin_bit_complement (0LL) != ~0LL
> + || __builtin_bit_complement (0x5aaaaaaa55555555LL) !=
> ~0x5aaaaaaa55555555LL
> + || !expr_has_type (__builtin_bit_complement (0LL), signed long long)
> + || __builtin_bit_complement ((_Bool) 0) != (_Bool) 1
> + || __builtin_bit_complement ((_Bool) 1) != (_Bool) 0
> + || !expr_has_type (__builtin_bit_complement ((_Bool) 0), _Bool)
> + || __builtin_bit_complement ((enum E) E0) != (enum E) ~0
> + || __builtin_bit_complement ((enum E) E1) != (enum E) ~1
> + || !expr_has_type (__builtin_bit_complement ((enum E) E0), enum E))
> + __builtin_abort ();
> +#if __SIZEOF_INT128__
> + if (__builtin_bit_complement ((unsigned __int128) 0) != ~(unsigned
> __int128) 0
> + || __builtin_bit_complement ((unsigned __int128)
> 0xaaaaaaaa55555555ULL) != ~(unsigned __int128) 0xaaaaaaaa55555555ULL
> + || !expr_has_type (__builtin_bit_complement ((unsigned __int128) 0),
> unsigned __int128)
> + || __builtin_bit_complement ((signed __int128) 0) != ~(signed
> __int128) 0
> + || __builtin_bit_complement ((signed __int128) 0x5aaaaaaa55555555LL)
> != ~(signed __int128) 0x5aaaaaaa55555555LL
> + || !expr_has_type (__builtin_bit_complement ((signed __int128) 0),
> signed __int128))
> + __builtin_abort ();
> +#endif
> +#if __has_builtin (__builtin_bit_complement) != 1
> +#error __builtin_bit_complement not implemented
> +#endif
> + unsigned char a = 0;
> + if (__builtin_bit_complement (a++) != (unsigned char) ~(unsigned char) 0
> + || a != 1)
> + __builtin_abort ();
> + if (!expr_has_type (__builtin_bit_complement (a++), unsigned char)
> + || a != 1)
> + __builtin_abort ();
> + unsigned short b = 0;
> + if (__builtin_bit_complement (b++) != (unsigned short) ~(unsigned short) 0
> + || b != 1)
> + __builtin_abort ();
> + if (!expr_has_type (__builtin_bit_complement (b++), unsigned short)
> + || b != 1)
> + __builtin_abort ();
> + int c = 0;
> + if (__builtin_bit_complement (c++) != ~0
> + || c != 1)
> + __builtin_abort ();
> + if (!expr_has_type (__builtin_bit_complement (c++), int)
> + || c != 1)
> + __builtin_abort ();
> +#if __BITINT_MAXWIDTH__ >= 256
> + if (__builtin_bit_complement (0uwb) != ~0uwb
> + || !expr_has_type (__builtin_bit_complement (0uwb), unsigned
> _BitInt(1))
> + || __builtin_bit_complement ((signed _BitInt(256)) 0) != ~(signed
> _BitInt(256)) 0
> + || !expr_has_type (__builtin_bit_complement ((signed _BitInt(256)) 0),
> signed _BitInt(256)))
> + __builtin_abort ();
> +#endif
> +}
> --- gcc/testsuite/gcc.dg/builtin-bit-complement-2.c.jj 2023-11-18
> 18:26:01.871634733 +0100
> +++ gcc/testsuite/gcc.dg/builtin-bit-complement-2.c 2023-11-18
> 18:32:55.448927364 +0100
> @@ -0,0 +1,16 @@
> +/* { dg-do compile } */
> +/* { dg-options "" } */
> +
> +void
> +foo (void)
> +{
> + typedef int V __attribute__ ((vector_size (4 * sizeof (int))));
> + struct S { int s; };
> + __builtin_bit_complement (0.0f); /* { dg-error
> "'__builtin_bit_complement' operand not an integral type" } */
> + __builtin_bit_complement (0.0); /* { dg-error
> "'__builtin_bit_complement' operand not an integral type" } */
> + __builtin_bit_complement (0.0L); /* { dg-error
> "'__builtin_bit_complement' operand not an integral type" } */
> + __builtin_bit_complement ((V) {}); /* { dg-error
> "'__builtin_bit_complement' operand not an integral type" } */
> + __builtin_bit_complement ((struct S) { 0 }); /* { dg-error
> "'__builtin_bit_complement' operand not an integral type" } */
> + __builtin_bit_complement (); /* { dg-error "wrong number of
> arguments to '__builtin_bit_complement'" } */
> + __builtin_bit_complement (0, 0); /* { dg-error "wrong number of
> arguments to '__builtin_bit_complement'" } */
> +}
>
> Jakub
>
