gcc/libgcc/libgcov.h
Eric Botcazou 9ec469f504 Add parallelism support to gcov for MinGW platforms
If you attempt a profiled bootstrap on the MinGW platforms with -jN, N > 1,
it miserably fails because of profile mismatches all over the place, the
reason being that gcov has no support for parallelism on these platforms.

libgcc/
	* libgcov.h: For the target, define GCOV_LOCKED_WITH_LOCKING
	if __MSVCRT__ and, for the host, define it if HOST_HAS_LK_LOCK.
	* libgcov-driver.c: Add directives if GCOV_LOCKED_WITH_LOCKING.
gcc/
	* configure.ac: Check for the presence of sys/locking.h header and
	for whether _LK_LOCK is supported by _locking.
	* configure: Regenerate.
	* config.in: Likewise.
	* gcov-io.h: Define GCOV_LOCKED_WITH_LOCKING if HOST_HAS_LK_LOCK.
	* gcov-io.c (gcov_open): Add support for GCOV_LOCKED_WITH_LOCKING.
	* system.h: Include <sys/locking.h> if HAVE_SYS_LOCKING_H.
2021-04-29 16:02:17 +02:00

592 lines
17 KiB
C

/* Header file for libgcov-*.c.
Copyright (C) 1996-2021 Free Software Foundation, Inc.
This file is part of GCC.
GCC 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 3, or (at your option) any later
version.
GCC 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.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
#ifndef GCC_LIBGCOV_H
#define GCC_LIBGCOV_H
/* work around the poisoned malloc/calloc in system.h. */
#ifndef xmalloc
#define xmalloc malloc
#endif
#ifndef xcalloc
#define xcalloc calloc
#endif
#ifndef IN_GCOV_TOOL
/* About the target. */
/* This path will be used by libgcov runtime. */
#include "tconfig.h"
#include "auto-target.h"
#include "tsystem.h"
#include "coretypes.h"
#include "tm.h"
#include "libgcc_tm.h"
#include "gcov.h"
#if HAVE_SYS_MMAN_H
#include <sys/mman.h>
#endif
#if __CHAR_BIT__ == 8
typedef unsigned gcov_unsigned_t __attribute__ ((mode (SI)));
typedef unsigned gcov_position_t __attribute__ ((mode (SI)));
#if LONG_LONG_TYPE_SIZE > 32
typedef signed gcov_type __attribute__ ((mode (DI)));
typedef unsigned gcov_type_unsigned __attribute__ ((mode (DI)));
#else
typedef signed gcov_type __attribute__ ((mode (SI)));
typedef unsigned gcov_type_unsigned __attribute__ ((mode (SI)));
#endif
#else
#if __CHAR_BIT__ == 16
typedef unsigned gcov_unsigned_t __attribute__ ((mode (HI)));
typedef unsigned gcov_position_t __attribute__ ((mode (HI)));
#if LONG_LONG_TYPE_SIZE > 32
typedef signed gcov_type __attribute__ ((mode (SI)));
typedef unsigned gcov_type_unsigned __attribute__ ((mode (SI)));
#else
typedef signed gcov_type __attribute__ ((mode (HI)));
typedef unsigned gcov_type_unsigned __attribute__ ((mode (HI)));
#endif
#else
typedef unsigned gcov_unsigned_t __attribute__ ((mode (QI)));
typedef unsigned gcov_position_t __attribute__ ((mode (QI)));
#if LONG_LONG_TYPE_SIZE > 32
typedef signed gcov_type __attribute__ ((mode (HI)));
typedef unsigned gcov_type_unsigned __attribute__ ((mode (HI)));
#else
typedef signed gcov_type __attribute__ ((mode (QI)));
typedef unsigned gcov_type_unsigned __attribute__ ((mode (QI)));
#endif
#endif
#endif
#if defined (TARGET_POSIX_IO)
#define GCOV_LOCKED 1
#else
#define GCOV_LOCKED 0
#endif
#if defined (__MSVCRT__)
#define GCOV_LOCKED_WITH_LOCKING 1
#else
#define GCOV_LOCKED_WITH_LOCKING 0
#endif
#ifndef GCOV_SUPPORTS_ATOMIC
/* Detect whether target can support atomic update of profilers. */
#if __SIZEOF_LONG_LONG__ == 4 && __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4
#define GCOV_SUPPORTS_ATOMIC 1
#else
#if __SIZEOF_LONG_LONG__ == 8 && __GCC_HAVE_SYNC_COMPARE_AND_SWAP_8
#define GCOV_SUPPORTS_ATOMIC 1
#else
#define GCOV_SUPPORTS_ATOMIC 0
#endif
#endif
#endif
/* In libgcov we need these functions to be extern, so prefix them with
__gcov. In libgcov they must also be hidden so that the instance in
the executable is not also used in a DSO. */
#define gcov_var __gcov_var
#define gcov_open __gcov_open
#define gcov_close __gcov_close
#define gcov_write_tag_length __gcov_write_tag_length
#define gcov_position __gcov_position
#define gcov_seek __gcov_seek
#define gcov_rewrite __gcov_rewrite
#define gcov_is_error __gcov_is_error
#define gcov_write_unsigned __gcov_write_unsigned
#define gcov_write_counter __gcov_write_counter
#define gcov_write_summary __gcov_write_summary
#define gcov_read_unsigned __gcov_read_unsigned
#define gcov_read_counter __gcov_read_counter
#define gcov_read_summary __gcov_read_summary
#else /* IN_GCOV_TOOL */
/* About the host. */
/* This path will be compiled for the host and linked into
gcov-tool binary. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
typedef unsigned gcov_unsigned_t;
typedef unsigned gcov_position_t;
/* gcov_type is typedef'd elsewhere for the compiler */
#if defined (HOST_HAS_F_SETLKW)
#define GCOV_LOCKED 1
#else
#define GCOV_LOCKED 0
#endif
#if defined (HOST_HAS_LK_LOCK)
#define GCOV_LOCKED_WITH_LOCKING 1
#else
#define GCOV_LOCKED_WITH_LOCKING 0
#endif
/* Some Macros specific to gcov-tool. */
#define L_gcov 1
#define L_gcov_merge_add 1
#define L_gcov_merge_topn 1
#define L_gcov_merge_ior 1
#define L_gcov_merge_time_profile 1
extern gcov_type gcov_read_counter_mem ();
extern unsigned gcov_get_merge_weight ();
extern struct gcov_info *gcov_list;
#endif /* !IN_GCOV_TOOL */
#if defined(inhibit_libc)
#define IN_LIBGCOV (-1)
#else
#define IN_LIBGCOV 1
#if defined(L_gcov)
#define GCOV_LINKAGE /* nothing */
#endif
#endif
/* Poison these, so they don't accidentally slip in. */
#pragma GCC poison gcov_write_string gcov_write_tag gcov_write_length
#pragma GCC poison gcov_time
#ifdef HAVE_GAS_HIDDEN
#define ATTRIBUTE_HIDDEN __attribute__ ((__visibility__ ("hidden")))
#else
#define ATTRIBUTE_HIDDEN
#endif
#if HAVE_SYS_MMAN_H
#ifndef MAP_FAILED
#define MAP_FAILED ((void *)-1)
#endif
#if !defined (MAP_ANONYMOUS) && defined (MAP_ANON)
#define MAP_ANONYMOUS MAP_ANON
#endif
#endif
#include "gcov-io.h"
/* Structures embedded in coveraged program. The structures generated
by write_profile must match these. */
/* Information about counters for a single function. */
struct gcov_ctr_info
{
gcov_unsigned_t num; /* number of counters. */
gcov_type *values; /* their values. */
};
/* Information about a single function. This uses the trailing array
idiom. The number of counters is determined from the merge pointer
array in gcov_info. The key is used to detect which of a set of
comdat functions was selected -- it points to the gcov_info object
of the object file containing the selected comdat function. */
struct gcov_fn_info
{
const struct gcov_info *key; /* comdat key */
gcov_unsigned_t ident; /* unique ident of function */
gcov_unsigned_t lineno_checksum; /* function lineo_checksum */
gcov_unsigned_t cfg_checksum; /* function cfg checksum */
struct gcov_ctr_info ctrs[1]; /* instrumented counters */
};
/* Type of function used to merge counters. */
typedef void (*gcov_merge_fn) (gcov_type *, gcov_unsigned_t);
/* Information about a single object file. */
struct gcov_info
{
gcov_unsigned_t version; /* expected version number */
struct gcov_info *next; /* link to next, used by libgcov */
gcov_unsigned_t stamp; /* uniquifying time stamp */
const char *filename; /* output file name */
gcov_merge_fn merge[GCOV_COUNTERS]; /* merge functions (null for
unused) */
unsigned n_functions; /* number of functions */
#ifndef IN_GCOV_TOOL
const struct gcov_fn_info *const *functions; /* pointer to pointers
to function information */
#else
struct gcov_fn_info **functions;
struct gcov_summary summary;
#endif /* !IN_GCOV_TOOL */
};
/* Root of a program/shared-object state */
struct gcov_root
{
struct gcov_info *list;
unsigned dumped : 1; /* counts have been dumped. */
unsigned run_counted : 1; /* run has been accounted for. */
struct gcov_root *next;
struct gcov_root *prev;
};
extern struct gcov_root __gcov_root ATTRIBUTE_HIDDEN;
struct gcov_master
{
gcov_unsigned_t version;
struct gcov_root *root;
};
struct indirect_call_tuple
{
/* Callee function. */
void *callee;
/* Pointer to counters. */
gcov_type *counters;
};
/* Exactly one of these will be active in the process. */
extern struct gcov_master __gcov_master;
extern struct gcov_kvp *__gcov_kvp_dynamic_pool;
extern unsigned __gcov_kvp_dynamic_pool_index;
extern unsigned __gcov_kvp_dynamic_pool_size;
/* Dump a set of gcov objects. */
extern void __gcov_dump_one (struct gcov_root *) ATTRIBUTE_HIDDEN;
/* Register a new object file module. */
extern void __gcov_init (struct gcov_info *) ATTRIBUTE_HIDDEN;
/* GCOV exit function registered via a static destructor. */
extern void __gcov_exit (void) ATTRIBUTE_HIDDEN;
/* Function to reset all counters to 0. Both externally visible (and
overridable) and internal version. */
extern void __gcov_reset_int (void) ATTRIBUTE_HIDDEN;
/* User function to enable early write of profile information so far. */
extern void __gcov_dump_int (void) ATTRIBUTE_HIDDEN;
/* Lock critical section for __gcov_dump and __gcov_reset functions. */
extern void __gcov_lock (void) ATTRIBUTE_HIDDEN;
/* Unlock critical section for __gcov_dump and __gcov_reset functions. */
extern void __gcov_unlock (void) ATTRIBUTE_HIDDEN;
/* The merge function that just sums the counters. */
extern void __gcov_merge_add (gcov_type *, unsigned) ATTRIBUTE_HIDDEN;
/* The merge function to select the minimum valid counter value. */
extern void __gcov_merge_time_profile (gcov_type *, unsigned) ATTRIBUTE_HIDDEN;
/* The merge function to choose the most common N values. */
extern void __gcov_merge_topn (gcov_type *, unsigned) ATTRIBUTE_HIDDEN;
/* The merge function that just ors the counters together. */
extern void __gcov_merge_ior (gcov_type *, unsigned) ATTRIBUTE_HIDDEN;
/* The profiler functions. */
extern void __gcov_interval_profiler (gcov_type *, gcov_type, int, unsigned);
extern void __gcov_interval_profiler_atomic (gcov_type *, gcov_type, int,
unsigned);
extern void __gcov_pow2_profiler (gcov_type *, gcov_type);
extern void __gcov_pow2_profiler_atomic (gcov_type *, gcov_type);
extern void __gcov_topn_values_profiler (gcov_type *, gcov_type);
extern void __gcov_topn_values_profiler_atomic (gcov_type *, gcov_type);
extern void __gcov_indirect_call_profiler_v4 (gcov_type, void *);
extern void __gcov_indirect_call_profiler_v4_atomic (gcov_type, void *);
extern void __gcov_time_profiler (gcov_type *);
extern void __gcov_time_profiler_atomic (gcov_type *);
extern void __gcov_average_profiler (gcov_type *, gcov_type);
extern void __gcov_average_profiler_atomic (gcov_type *, gcov_type);
extern void __gcov_ior_profiler (gcov_type *, gcov_type);
extern void __gcov_ior_profiler_atomic (gcov_type *, gcov_type);
#ifndef inhibit_libc
/* The wrappers around some library functions.. */
extern pid_t __gcov_fork (void) ATTRIBUTE_HIDDEN;
extern int __gcov_execl (const char *, char *, ...) ATTRIBUTE_HIDDEN;
extern int __gcov_execlp (const char *, char *, ...) ATTRIBUTE_HIDDEN;
extern int __gcov_execle (const char *, char *, ...) ATTRIBUTE_HIDDEN;
extern int __gcov_execv (const char *, char *const []) ATTRIBUTE_HIDDEN;
extern int __gcov_execvp (const char *, char *const []) ATTRIBUTE_HIDDEN;
extern int __gcov_execve (const char *, char *const [], char *const [])
ATTRIBUTE_HIDDEN;
/* Functions that only available in libgcov. */
GCOV_LINKAGE int gcov_open (const char */*name*/) ATTRIBUTE_HIDDEN;
GCOV_LINKAGE void gcov_write_counter (gcov_type) ATTRIBUTE_HIDDEN;
GCOV_LINKAGE void gcov_write_tag_length (gcov_unsigned_t, gcov_unsigned_t)
ATTRIBUTE_HIDDEN;
GCOV_LINKAGE void gcov_write_summary (gcov_unsigned_t /*tag*/,
const struct gcov_summary *)
ATTRIBUTE_HIDDEN;
GCOV_LINKAGE void gcov_seek (gcov_position_t /*position*/) ATTRIBUTE_HIDDEN;
GCOV_LINKAGE void gcov_rewrite (void) ATTRIBUTE_HIDDEN;
/* "Counts" stored in gcda files can be a real counter value, or
an target address. When differentiate these two types because
when manipulating counts, we should only change real counter values,
rather target addresses. */
static inline gcov_type
gcov_get_counter (void)
{
#ifndef IN_GCOV_TOOL
/* This version is for reading count values in libgcov runtime:
we read from gcda files. */
return gcov_read_counter ();
#else
/* This version is for gcov-tool. We read the value from memory and
multiply it by the merge weight. */
return gcov_read_counter_mem () * gcov_get_merge_weight ();
#endif
}
/* Similar function as gcov_get_counter(), but do not scale
when read value is equal to IGNORE_SCALING. */
static inline gcov_type
gcov_get_counter_ignore_scaling (gcov_type ignore_scaling ATTRIBUTE_UNUSED)
{
#ifndef IN_GCOV_TOOL
/* This version is for reading count values in libgcov runtime:
we read from gcda files. */
return gcov_read_counter ();
#else
/* This version is for gcov-tool. We read the value from memory and
multiply it by the merge weight. */
gcov_type v = gcov_read_counter_mem ();
if (v != ignore_scaling)
v *= gcov_get_merge_weight ();
return v;
#endif
}
/* Similar function as gcov_get_counter(), but handles target address
counters. */
static inline gcov_type
gcov_get_counter_target (void)
{
#ifndef IN_GCOV_TOOL
/* This version is for reading count target values in libgcov runtime:
we read from gcda files. */
return gcov_read_counter ();
#else
/* This version is for gcov-tool. We read the value from memory and we do NOT
multiply it by the merge weight. */
return gcov_read_counter_mem ();
#endif
}
/* Add VALUE to *COUNTER and make it with atomic operation
if USE_ATOMIC is true. */
static inline void
gcov_counter_add (gcov_type *counter, gcov_type value,
int use_atomic ATTRIBUTE_UNUSED)
{
#if GCOV_SUPPORTS_ATOMIC
if (use_atomic)
__atomic_fetch_add (counter, value, __ATOMIC_RELAXED);
else
#endif
*counter += value;
}
#if HAVE_SYS_MMAN_H
/* Allocate LENGTH with mmap function. */
static inline void *
malloc_mmap (size_t length)
{
return mmap (NULL, length, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
}
#endif
/* Allocate gcov_kvp from statically pre-allocated pool,
or use heap otherwise. */
static inline struct gcov_kvp *
allocate_gcov_kvp (void)
{
#define MMAP_CHUNK_SIZE (128 * 1024)
struct gcov_kvp *new_node = NULL;
unsigned kvp_sizeof = sizeof(struct gcov_kvp);
/* Try mmaped pool if available. */
#if !defined(IN_GCOV_TOOL) && !defined(L_gcov_merge_topn) && HAVE_SYS_MMAN_H
if (__gcov_kvp_dynamic_pool == NULL
|| __gcov_kvp_dynamic_pool_index >= __gcov_kvp_dynamic_pool_size)
{
void *ptr = malloc_mmap (MMAP_CHUNK_SIZE);
if (ptr != MAP_FAILED)
{
__gcov_kvp_dynamic_pool = ptr;
__gcov_kvp_dynamic_pool_size = MMAP_CHUNK_SIZE / kvp_sizeof;
__gcov_kvp_dynamic_pool_index = 0;
}
}
if (__gcov_kvp_dynamic_pool != NULL)
{
unsigned index;
#if GCOV_SUPPORTS_ATOMIC
index
= __atomic_fetch_add (&__gcov_kvp_dynamic_pool_index, 1,
__ATOMIC_RELAXED);
#else
index = __gcov_kvp_dynamic_pool_index++;
#endif
if (index < __gcov_kvp_dynamic_pool_size)
new_node = __gcov_kvp_dynamic_pool + index;
}
#endif
/* Fallback to malloc. */
if (new_node == NULL)
new_node = (struct gcov_kvp *)xcalloc (1, kvp_sizeof);
return new_node;
}
/* Add key value pair VALUE:COUNT to a top N COUNTERS. When INCREMENT_TOTAL
is true, add COUNT to total of the TOP counter. If USE_ATOMIC is true,
do it in atomic way. Return true when the counter is full, otherwise
return false. */
static inline unsigned
gcov_topn_add_value (gcov_type *counters, gcov_type value, gcov_type count,
int use_atomic, int increment_total)
{
if (increment_total)
{
/* In the multi-threaded mode, we can have an already merged profile
with a negative total value. In that case, we should bail out. */
if (counters[0] < 0)
return 0;
gcov_counter_add (&counters[0], 1, use_atomic);
}
struct gcov_kvp *prev_node = NULL;
struct gcov_kvp *minimal_node = NULL;
struct gcov_kvp *current_node = (struct gcov_kvp *)(intptr_t)counters[2];
while (current_node)
{
if (current_node->value == value)
{
gcov_counter_add (&current_node->count, count, use_atomic);
return 0;
}
if (minimal_node == NULL
|| current_node->count < minimal_node->count)
minimal_node = current_node;
prev_node = current_node;
current_node = current_node->next;
}
if (counters[1] == GCOV_TOPN_MAXIMUM_TRACKED_VALUES)
{
if (--minimal_node->count < count)
{
minimal_node->value = value;
minimal_node->count = count;
}
return 1;
}
else
{
struct gcov_kvp *new_node = allocate_gcov_kvp ();
if (new_node == NULL)
return 0;
new_node->value = value;
new_node->count = count;
int success = 0;
if (!counters[2])
{
#if GCOV_SUPPORTS_ATOMIC
if (use_atomic)
{
struct gcov_kvp **ptr = (struct gcov_kvp **)(intptr_t)&counters[2];
success = !__sync_val_compare_and_swap (ptr, 0, new_node);
}
else
#endif
{
counters[2] = (intptr_t)new_node;
success = 1;
}
}
else if (prev_node && !prev_node->next)
{
#if GCOV_SUPPORTS_ATOMIC
if (use_atomic)
success = !__sync_val_compare_and_swap (&prev_node->next, 0,
new_node);
else
#endif
{
prev_node->next = new_node;
success = 1;
}
}
/* Increment number of nodes. */
if (success)
gcov_counter_add (&counters[1], 1, use_atomic);
}
return 0;
}
#endif /* !inhibit_libc */
#endif /* GCC_LIBGCOV_H */