| /*===- GCDAProfiling.c - Support library for GCDA file emission -----------===*\ |
| |* |
| |* The LLVM Compiler Infrastructure |
| |* |
| |* This file is distributed under the University of Illinois Open Source |
| |* License. See LICENSE.TXT for details. |
| |* |
| |*===----------------------------------------------------------------------===*| |
| |* |
| |* This file implements the call back routines for the gcov profiling |
| |* instrumentation pass. Link against this library when running code through |
| |* the -insert-gcov-profiling LLVM pass. |
| |* |
| |* We emit files in a corrupt version of GCOV's "gcda" file format. These files |
| |* are only close enough that LCOV will happily parse them. Anything that lcov |
| |* ignores is missing. |
| |* |
| |* TODO: gcov is multi-process safe by having each exit open the existing file |
| |* and append to it. We'd like to achieve that and be thread-safe too. |
| |* |
| \*===----------------------------------------------------------------------===*/ |
| |
| #include "llvm/Support/DataTypes.h" |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| /* #define DEBUG_GCDAPROFILING */ |
| |
| /* |
| * --- GCOV file format I/O primitives --- |
| */ |
| |
| static FILE *output_file = NULL; |
| |
| static void write_int32(uint32_t i) { |
| fwrite(&i, 4, 1, output_file); |
| } |
| |
| static void write_int64(uint64_t i) { |
| uint32_t lo, hi; |
| lo = i >> 0; |
| hi = i >> 32; |
| |
| write_int32(lo); |
| write_int32(hi); |
| } |
| |
| static char *mangle_filename(const char *orig_filename) { |
| /* TODO: handle GCOV_PREFIX_STRIP */ |
| const char *prefix; |
| char *filename = 0; |
| |
| prefix = getenv("GCOV_PREFIX"); |
| |
| if (!prefix) |
| return strdup(filename); |
| |
| filename = malloc(strlen(prefix) + 1 + strlen(orig_filename) + 1); |
| strcpy(filename, prefix); |
| strcat(filename, "/"); |
| strcat(filename, orig_filename); |
| |
| return filename; |
| } |
| |
| /* |
| * --- LLVM line counter API --- |
| */ |
| |
| /* A file in this case is a translation unit. Each .o file built with line |
| * profiling enabled will emit to a different file. Only one file may be |
| * started at a time. |
| */ |
| void llvm_gcda_start_file(const char *orig_filename) { |
| char *filename; |
| filename = mangle_filename(orig_filename); |
| output_file = fopen(filename, "wb"); |
| |
| /* gcda file, version 404*, stamp LLVM. */ |
| fwrite("adcg*404MVLL", 12, 1, output_file); |
| |
| #ifdef DEBUG_GCDAPROFILING |
| printf("llvmgcda: [%s]\n", orig_filename); |
| #endif |
| |
| free(filename); |
| } |
| |
| /* Given an array of pointers to counters (counters), increment the n-th one, |
| * where we're also given a pointer to n (predecessor). |
| */ |
| void llvm_gcda_increment_indirect_counter(uint32_t *predecessor, |
| uint64_t **counters) { |
| uint64_t *counter; |
| uint32_t pred; |
| |
| pred = *predecessor; |
| if (pred == 0xffffffff) |
| return; |
| counter = counters[pred]; |
| |
| /* Don't crash if the pred# is out of sync. This can happen due to threads, |
| or because of a TODO in GCOVProfiling.cpp buildEdgeLookupTable(). */ |
| if (counter) |
| ++*counter; |
| #ifdef DEBUG_GCDAPROFILING |
| else |
| printf("llvmgcda: increment_indirect_counter counters=%x, pred=%u\n", |
| state_table_row, *predecessor); |
| #endif |
| } |
| |
| void llvm_gcda_emit_function(uint32_t ident) { |
| #ifdef DEBUG_GCDAPROFILING |
| printf("llvmgcda: function id=%x\n", ident); |
| #endif |
| |
| /* function tag */ |
| fwrite("\0\0\0\1", 4, 1, output_file); |
| write_int32(2); |
| write_int32(ident); |
| write_int32(0); |
| } |
| |
| void llvm_gcda_emit_arcs(uint32_t num_counters, uint64_t *counters) { |
| uint32_t i; |
| /* counter #1 (arcs) tag */ |
| fwrite("\0\0\xa1\1", 4, 1, output_file); |
| write_int32(num_counters * 2); |
| for (i = 0; i < num_counters; ++i) { |
| write_int64(counters[i]); |
| } |
| |
| #ifdef DEBUG_GCDAPROFILING |
| printf("llvmgcda: %u arcs\n", num_counters); |
| for (i = 0; i < num_counters; ++i) { |
| printf("llvmgcda: %llu\n", (unsigned long long)counters[i]); |
| } |
| #endif |
| } |
| |
| void llvm_gcda_end_file() { |
| /* Write out EOF record. */ |
| fwrite("\0\0\0\0\0\0\0\0", 8, 1, output_file); |
| fclose(output_file); |
| output_file = NULL; |
| |
| #ifdef DEBUG_GCDAPROFILING |
| printf("llvmgcda: -----\n"); |
| #endif |
| } |