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Diffstat (limited to 'libgcc/libgcov-profiler.c')
| -rw-r--r-- | libgcc/libgcov-profiler.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/libgcc/libgcov-profiler.c b/libgcc/libgcov-profiler.c new file mode 100644 index 0000000..6ba1bcf --- /dev/null +++ b/libgcc/libgcov-profiler.c @@ -0,0 +1,223 @@ +/* Routines required for instrumenting a program. */ +/* Compile this one with gcc. */ +/* Copyright (C) 1989-2013 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/>. */ + +#include "tconfig.h" +#include "tsystem.h" +#include "coretypes.h" +#include "tm.h" +#include "libgcc_tm.h" + +#if !defined(inhibit_libc) +#define IN_LIBGCOV 1 +#include "gcov-io.h" + +#ifdef L_gcov_interval_profiler +/* If VALUE is in interval <START, START + STEPS - 1>, then increases the + corresponding counter in COUNTERS. If the VALUE is above or below + the interval, COUNTERS[STEPS] or COUNTERS[STEPS + 1] is increased + instead. */ + +void +__gcov_interval_profiler (gcov_type *counters, gcov_type value, + int start, unsigned steps) +{ + gcov_type delta = value - start; + if (delta < 0) + counters[steps + 1]++; + else if (delta >= steps) + counters[steps]++; + else + counters[delta]++; +} +#endif + +#ifdef L_gcov_pow2_profiler +/* If VALUE is a power of two, COUNTERS[1] is incremented. Otherwise + COUNTERS[0] is incremented. */ + +void +__gcov_pow2_profiler (gcov_type *counters, gcov_type value) +{ + if (value & (value - 1)) + counters[0]++; + else + counters[1]++; +} +#endif + +/* Tries to determine the most common value among its inputs. Checks if the + value stored in COUNTERS[0] matches VALUE. If this is the case, COUNTERS[1] + is incremented. If this is not the case and COUNTERS[1] is not zero, + COUNTERS[1] is decremented. Otherwise COUNTERS[1] is set to one and + VALUE is stored to COUNTERS[0]. This algorithm guarantees that if this + function is called more than 50% of the time with one value, this value + will be in COUNTERS[0] in the end. + + In any case, COUNTERS[2] is incremented. */ + +static inline void +__gcov_one_value_profiler_body (gcov_type *counters, gcov_type value) +{ + if (value == counters[0]) + counters[1]++; + else if (counters[1] == 0) + { + counters[1] = 1; + counters[0] = value; + } + else + counters[1]--; + counters[2]++; +} + +#ifdef L_gcov_one_value_profiler +void +__gcov_one_value_profiler (gcov_type *counters, gcov_type value) +{ + __gcov_one_value_profiler_body (counters, value); +} +#endif + +#ifdef L_gcov_indirect_call_profiler +/* This function exist only for workaround of binutils bug 14342. + Once this compatibility hack is obsolette, it can be removed. */ + +/* By default, the C++ compiler will use function addresses in the + vtable entries. Setting TARGET_VTABLE_USES_DESCRIPTORS to nonzero + tells the compiler to use function descriptors instead. The value + of this macro says how many words wide the descriptor is (normally 2), + but it may be dependent on target flags. Since we do not have access + to the target flags here we just check to see if it is set and use + that to set VTABLE_USES_DESCRIPTORS to 0 or 1. + + It is assumed that the address of a function descriptor may be treated + as a pointer to a function. */ + +#ifdef TARGET_VTABLE_USES_DESCRIPTORS +#define VTABLE_USES_DESCRIPTORS 1 +#else +#define VTABLE_USES_DESCRIPTORS 0 +#endif + +/* Tries to determine the most common value among its inputs. */ +void +__gcov_indirect_call_profiler (gcov_type* counter, gcov_type value, + void* cur_func, void* callee_func) +{ + /* If the C++ virtual tables contain function descriptors then one + function may have multiple descriptors and we need to dereference + the descriptors to see if they point to the same function. */ + if (cur_func == callee_func + || (VTABLE_USES_DESCRIPTORS && callee_func + && *(void **) cur_func == *(void **) callee_func)) + __gcov_one_value_profiler_body (counter, value); +} + +#endif +#ifdef L_gcov_indirect_call_profiler_v2 + +/* These two variables are used to actually track caller and callee. Keep + them in TLS memory so races are not common (they are written to often). + The variables are set directly by GCC instrumented code, so declaration + here must match one in tree-profile.c */ + +#if defined(HAVE_CC_TLS) && !defined (USE_EMUTLS) +__thread +#endif +void * __gcov_indirect_call_callee; +#if defined(HAVE_CC_TLS) && !defined (USE_EMUTLS) +__thread +#endif +gcov_type * __gcov_indirect_call_counters; + +/* By default, the C++ compiler will use function addresses in the + vtable entries. Setting TARGET_VTABLE_USES_DESCRIPTORS to nonzero + tells the compiler to use function descriptors instead. The value + of this macro says how many words wide the descriptor is (normally 2), + but it may be dependent on target flags. Since we do not have access + to the target flags here we just check to see if it is set and use + that to set VTABLE_USES_DESCRIPTORS to 0 or 1. + + It is assumed that the address of a function descriptor may be treated + as a pointer to a function. */ + +#ifdef TARGET_VTABLE_USES_DESCRIPTORS +#define VTABLE_USES_DESCRIPTORS 1 +#else +#define VTABLE_USES_DESCRIPTORS 0 +#endif + +/* Tries to determine the most common value among its inputs. */ +void +__gcov_indirect_call_profiler_v2 (gcov_type value, void* cur_func) +{ + /* If the C++ virtual tables contain function descriptors then one + function may have multiple descriptors and we need to dereference + the descriptors to see if they point to the same function. */ + if (cur_func == __gcov_indirect_call_callee + || (VTABLE_USES_DESCRIPTORS && __gcov_indirect_call_callee + && *(void **) cur_func == *(void **) __gcov_indirect_call_callee)) + __gcov_one_value_profiler_body (__gcov_indirect_call_counters, value); +} +#endif + +#ifdef L_gcov_time_profiler + +/* Counter for first visit of each function. */ +static gcov_type function_counter; + +/* Sets corresponding COUNTERS if there is no value. */ + +void +__gcov_time_profiler (gcov_type* counters) +{ + if (!counters[0]) + counters[0] = ++function_counter; +} +#endif + +#ifdef L_gcov_average_profiler +/* Increase corresponding COUNTER by VALUE. FIXME: Perhaps we want + to saturate up. */ + +void +__gcov_average_profiler (gcov_type *counters, gcov_type value) +{ + counters[0] += value; + counters[1] ++; +} +#endif + +#ifdef L_gcov_ior_profiler +/* Bitwise-OR VALUE into COUNTER. */ + +void +__gcov_ior_profiler (gcov_type *counters, gcov_type value) +{ + *counters |= value; +} +#endif + +#endif /* inhibit_libc */ |