gcc/libiberty/cp-demangle.h
Jakub Jelinek c2565a31c1 middle-end, c++, i386, libgcc: std::bfloat16_t and __bf16 arithmetic support
Here is a complete patch to add std::bfloat16_t support on
x86 (AArch64 and ARM left for later).  Almost no BFmode optabs
are added by the patch, so for binops/unops it extends to SFmode
first and then truncates back to BFmode.
For {HF,SF,DF,XF,TF}mode -> BFmode conversions libgcc has implementations
of all those conversions so that we avoid double rounding, for
BFmode -> {DF,XF,TF}mode conversions to avoid growing libgcc too much
it emits BFmode -> SFmode conversion first and then converts to the even
wider mode, neither step should be imprecise.
For BFmode -> HFmode, it first emits a precise BFmode -> SFmode conversion
and then SFmode -> HFmode, because neither format is subset or superset
of the other, while SFmode is superset of both.
expr.cc then contains a -ffast-math optimization of the BF -> SF and
SF -> BF conversions if we don't optimize for space (and for the latter
if -frounding-math isn't enabled either).
For x86, perhaps truncsfbf2 optab could be defined for TARGET_AVX512BF16
but IMNSHO should FAIL if !flag_finite_math || flag_rounding_math
|| !flag_unsafe_math_optimizations, because I think the insn doesn't
raise on sNaNs, hardcodes round to nearest and flushes denormals to zero.
By default (unless x86 -fexcess-precision=16) we use float excess
precision for BFmode, so truncate only on explicit casts and assignments.
The patch introduces a single __bf16 builtin - __builtin_nansf16b,
because (__bf16) __builtin_nansf ("") will drop the sNaN into qNaN,
and uses f16b suffix instead of bf16 because there would be ambiguity on
log vs. logb - __builtin_logbf16 could be either log with bf16 suffix
or logb with f16 suffix.  In other cases libstdc++ should mostly use
__builtin_*f for std::bfloat16_t overloads (we have a problem with
std::nextafter though but that one we have also for std::float16_t).

2022-10-14  Jakub Jelinek  <jakub@redhat.com>

gcc/
	* tree-core.h (enum tree_index): Add TI_BFLOAT16_TYPE.
	* tree.h (bfloat16_type_node): Define.
	* tree.cc (excess_precision_type): Promote bfloat16_type_mode
	like float16_type_mode.
	(build_common_tree_nodes): Initialize bfloat16_type_node if
	BFmode is supported.
	* expmed.h (maybe_expand_shift): Declare.
	* expmed.cc (maybe_expand_shift): No longer static.
	* expr.cc (convert_mode_scalar): Don't ICE on BF -> HF or HF -> BF
	conversions.  If there is no optab, handle BF -> {DF,XF,TF,HF}
	conversions as separate BF -> SF -> {DF,XF,TF,HF} conversions, add
	-ffast-math generic implementation for BF -> SF and SF -> BF
	conversions.
	* builtin-types.def (BT_BFLOAT16, BT_FN_BFLOAT16_CONST_STRING): New.
	* builtins.def (BUILT_IN_NANSF16B): New builtin.
	* fold-const-call.cc (fold_const_call): Handle CFN_BUILT_IN_NANSF16B.
	* config/i386/i386.cc (classify_argument): Handle E_BCmode.
	(ix86_libgcc_floating_mode_supported_p): Also return true for BFmode
	for -msse2.
	(ix86_mangle_type): Mangle BFmode as DF16b.
	(ix86_invalid_conversion, ix86_invalid_unary_op,
	ix86_invalid_binary_op): Remove.
	(TARGET_INVALID_CONVERSION, TARGET_INVALID_UNARY_OP,
	TARGET_INVALID_BINARY_OP): Don't redefine.
	* config/i386/i386-builtins.cc (ix86_bf16_type_node): Remove.
	(ix86_register_bf16_builtin_type): Use bfloat16_type_node rather than
	ix86_bf16_type_node, only create it if still NULL.
	* config/i386/i386-builtin-types.def (BFLOAT16): Likewise.
	* config/i386/i386.md (cbranchbf4, cstorebf4): New expanders.
gcc/c-family/
	* c-cppbuiltin.cc (c_cpp_builtins): If bfloat16_type_node,
	predefine __BFLT16_*__ macros and for C++23 also
	__STDCPP_BFLOAT16_T__.  Predefine bfloat16_type_node related
	macros for -fbuilding-libgcc.
	* c-lex.cc (interpret_float): Handle CPP_N_BFLOAT16.
gcc/c/
	* c-typeck.cc (convert_arguments): Don't promote __bf16 to
	double.
gcc/cp/
	* cp-tree.h (extended_float_type_p): Return true for
	bfloat16_type_node.
	* typeck.cc (cp_compare_floating_point_conversion_ranks): Set
	extended{1,2} if mv{1,2} is bfloat16_type_node.  Adjust comment.
gcc/testsuite/
	* lib/target-supports.exp (check_effective_target_bfloat16,
	check_effective_target_bfloat16_runtime, add_options_for_bfloat16):
	New.
	* gcc.dg/torture/bfloat16-basic.c: New test.
	* gcc.dg/torture/bfloat16-builtin.c: New test.
	* gcc.dg/torture/bfloat16-builtin-issignaling-1.c: New test.
	* gcc.dg/torture/bfloat16-complex.c: New test.
	* gcc.dg/torture/builtin-issignaling-1.c: Allow to be includable
	from bfloat16-builtin-issignaling-1.c.
	* gcc.dg/torture/floatn-basic.h: Allow to be includable from
	bfloat16-basic.c.
	* gcc.target/i386/vect-bfloat16-typecheck_2.c: Adjust expected
	diagnostics.
	* gcc.target/i386/sse2-bfloat16-scalar-typecheck.c: Likewise.
	* gcc.target/i386/vect-bfloat16-typecheck_1.c: Likewise.
	* g++.target/i386/bfloat_cpp_typecheck.C: Likewise.
libcpp/
	* include/cpplib.h (CPP_N_BFLOAT16): Define.
	* expr.cc (interpret_float_suffix): Handle bf16 and BF16 suffixes for
	C++.
libgcc/
	* config/i386/t-softfp (softfp_extensions): Add bfsf.
	(softfp_truncations): Add tfbf xfbf dfbf sfbf hfbf.
	(CFLAGS-extendbfsf2.c, CFLAGS-truncsfbf2.c, CFLAGS-truncdfbf2.c,
	CFLAGS-truncxfbf2.c, CFLAGS-trunctfbf2.c, CFLAGS-trunchfbf2.c): Add
	-msse2.
	* config/i386/libgcc-glibc.ver (GCC_13.0.0): Export
	__extendbfsf2 and __trunc{s,d,x,t,h}fbf2.
	* config/i386/sfp-machine.h (_FP_NANSIGN_B): Define.
	* config/i386/64/sfp-machine.h (_FP_NANFRAC_B): Define.
	* config/i386/32/sfp-machine.h (_FP_NANFRAC_B): Define.
	* soft-fp/brain.h: New file.
	* soft-fp/truncsfbf2.c: New file.
	* soft-fp/truncdfbf2.c: New file.
	* soft-fp/truncxfbf2.c: New file.
	* soft-fp/trunctfbf2.c: New file.
	* soft-fp/trunchfbf2.c: New file.
	* soft-fp/truncbfhf2.c: New file.
	* soft-fp/extendbfsf2.c: New file.
libiberty/
	* cp-demangle.h (D_BUILTIN_TYPE_COUNT): Increment.
	* cp-demangle.c (cplus_demangle_builtin_types): Add std::bfloat16_t
	entry.
	(cplus_demangle_type): Demangle DF16b.
	* testsuite/demangle-expected (_Z3xxxDF16b): New test.
2022-10-14 09:37:01 +02:00

201 lines
6 KiB
C

/* Internal demangler interface for g++ V3 ABI.
Copyright (C) 2003-2022 Free Software Foundation, Inc.
Written by Ian Lance Taylor <ian@wasabisystems.com>.
This file is part of the libiberty library, which is part of GCC.
This file is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
In addition to the permissions in the GNU General Public License, the
Free Software Foundation gives you unlimited permission to link the
compiled version of this file into combinations with other programs,
and to distribute those combinations without any restriction coming
from the use of this file. (The General Public License restrictions
do apply in other respects; for example, they cover modification of
the file, and distribution when not linked into a combined
executable.)
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.
*/
/* This file provides some definitions shared by cp-demangle.c and
cp-demint.c. It should not be included by any other files. */
/* Information we keep for operators. */
struct demangle_operator_info
{
/* Mangled name. */
const char *code;
/* Real name. */
const char *name;
/* Length of real name. */
int len;
/* Number of arguments. */
int args;
};
/* How to print the value of a builtin type. */
enum d_builtin_type_print
{
/* Print as (type)val. */
D_PRINT_DEFAULT,
/* Print as integer. */
D_PRINT_INT,
/* Print as unsigned integer, with trailing "u". */
D_PRINT_UNSIGNED,
/* Print as long, with trailing "l". */
D_PRINT_LONG,
/* Print as unsigned long, with trailing "ul". */
D_PRINT_UNSIGNED_LONG,
/* Print as long long, with trailing "ll". */
D_PRINT_LONG_LONG,
/* Print as unsigned long long, with trailing "ull". */
D_PRINT_UNSIGNED_LONG_LONG,
/* Print as bool. */
D_PRINT_BOOL,
/* Print as float--put value in square brackets. */
D_PRINT_FLOAT,
/* Print in usual way, but here to detect void. */
D_PRINT_VOID
};
/* Information we keep for a builtin type. */
struct demangle_builtin_type_info
{
/* Type name. */
const char *name;
/* Length of type name. */
int len;
/* Type name when using Java. */
const char *java_name;
/* Length of java name. */
int java_len;
/* How to print a value of this type. */
enum d_builtin_type_print print;
};
/* The information structure we pass around. */
struct d_info
{
/* The string we are demangling. */
const char *s;
/* The end of the string we are demangling. */
const char *send;
/* The options passed to the demangler. */
int options;
/* The next character in the string to consider. */
const char *n;
/* The array of components. */
struct demangle_component *comps;
/* The index of the next available component. */
int next_comp;
/* The number of available component structures. */
int num_comps;
/* The array of substitutions. */
struct demangle_component **subs;
/* The index of the next substitution. */
int next_sub;
/* The number of available entries in the subs array. */
int num_subs;
/* The last name we saw, for constructors and destructors. */
struct demangle_component *last_name;
/* A running total of the length of large expansions from the
mangled name to the demangled name, such as standard
substitutions and builtin types. */
int expansion;
/* Non-zero if we are parsing an expression. */
int is_expression;
/* Non-zero if we are parsing the type operand of a conversion
operator, but not when in an expression. */
int is_conversion;
/* 1: using new unresolved-name grammar.
-1: using new unresolved-name grammar and saw an unresolved-name.
0: using old unresolved-name grammar. */
int unresolved_name_state;
/* If DMGL_NO_RECURSE_LIMIT is not active then this is set to
the current recursion level. */
unsigned int recursion_level;
};
/* To avoid running past the ending '\0', don't:
- call d_peek_next_char if d_peek_char returned '\0'
- call d_advance with an 'i' that is too large
- call d_check_char(di, '\0')
Everything else is safe. */
#define d_peek_char(di) (*((di)->n))
#ifndef CHECK_DEMANGLER
# define d_peek_next_char(di) ((di)->n[1])
# define d_advance(di, i) ((di)->n += (i))
#endif
#define d_check_char(di, c) (d_peek_char(di) == c ? ((di)->n++, 1) : 0)
#define d_next_char(di) (d_peek_char(di) == '\0' ? '\0' : *((di)->n++))
#define d_str(di) ((di)->n)
#ifdef CHECK_DEMANGLER
static inline char
d_peek_next_char (const struct d_info *di)
{
if (!di->n[0])
abort ();
return di->n[1];
}
static inline void
d_advance (struct d_info *di, int i)
{
if (i < 0)
abort ();
while (i--)
{
if (!di->n[0])
abort ();
di->n++;
}
}
#endif
/* Functions and arrays in cp-demangle.c which are referenced by
functions in cp-demint.c. */
#ifdef IN_GLIBCPP_V3
#define CP_STATIC_IF_GLIBCPP_V3 static
#else
#define CP_STATIC_IF_GLIBCPP_V3 extern
#endif
#ifndef IN_GLIBCPP_V3
extern const struct demangle_operator_info cplus_demangle_operators[];
#endif
#define D_BUILTIN_TYPE_COUNT (36)
CP_STATIC_IF_GLIBCPP_V3
const struct demangle_builtin_type_info
cplus_demangle_builtin_types[D_BUILTIN_TYPE_COUNT];
CP_STATIC_IF_GLIBCPP_V3
struct demangle_component *
cplus_demangle_mangled_name (struct d_info *, int);
CP_STATIC_IF_GLIBCPP_V3
struct demangle_component *
cplus_demangle_type (struct d_info *);
extern void
cplus_demangle_init_info (const char *, int, size_t, struct d_info *);
/* cp-demangle.c needs to define this a little differently */
#undef CP_STATIC_IF_GLIBCPP_V3