Performance improvement.
Using fwrite and fread was very *very* slow. The resulting code was multiple
times slower than GCC's implementation of gcov. Replace the fwrite/fread system
with an mmap() version.
If the `.gcda' file doesn't exist, we (re)allocate a buffer that we write
into. That gets written to the `.gcda' file in one chunk. If the `.gcda' file
already exists, we simply mmap() the file, modify the mapped data, and use
msync() to write the contents out to disk. It's much easier than implementing
our own buffering scheme, and we don't have to use fwrite's and fread's
buffering.
For those who are numbers-oriented, here are some timings:
GCC Verison
-----------
`.gcda' files don't exist: 23s
`.gcda' files do exist: 14s
LLVM Version (before this change)
---------------------------------
`.gcda' files don't exist: 28s
`.gcda' files do exist: 28s
LLVM Version (with this change)
-------------------------------
`.gcda' files don't exist: 18s
`.gcda' files do exist: 4s
It's a win-win-win-win-lose-win-win scenario!
<rdar://problem/13466086>
git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@182563 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/SDKs/linux/usr/include/fcntl.h b/SDKs/linux/usr/include/fcntl.h
new file mode 100644
index 0000000..a5f91e3
--- /dev/null
+++ b/SDKs/linux/usr/include/fcntl.h
@@ -0,0 +1,17 @@
+/* ===-- fcntl.h - stub SDK header for compiler-rt --------------------------===
+ *
+ * The LLVM Compiler Infrastructure
+ *
+ * This file is dual licensed under the MIT and the University of Illinois Open
+ * Source Licenses. See LICENSE.TXT for details.
+ *
+ * ===-----------------------------------------------------------------------===
+ *
+ * This is a stub SDK header file. This file is not part of the interface of
+ * this library nor an official version of the appropriate SDK header. It is
+ * intended only to stub the features of this header required by compiler-rt.
+ *
+ * ===-----------------------------------------------------------------------===
+ */
+
+#include <sys/fcntl.h>
diff --git a/SDKs/linux/usr/include/stdio.h b/SDKs/linux/usr/include/stdio.h
index 0ca10fa..fba5936 100644
--- a/SDKs/linux/usr/include/stdio.h
+++ b/SDKs/linux/usr/include/stdio.h
@@ -33,11 +33,11 @@
extern int fclose(FILE *);
extern int fflush(FILE *);
extern FILE *fopen(const char * restrict, const char * restrict);
+extern FILE *fdopen(int, const char * restrict);
extern int fprintf(FILE * restrict, const char * restrict, ...);
extern size_t fwrite(const void * restrict, size_t, size_t, FILE * restrict);
extern size_t fread(void * restrict, size_t, size_t, FILE * restrict);
extern long ftell(FILE *);
extern int fseek(FILE *, long, int);
-extern void setbuf(FILE * restrict, char * restrict);
#endif /* __STDIO_H__ */
diff --git a/SDKs/linux/usr/include/stdlib.h b/SDKs/linux/usr/include/stdlib.h
index e6b8bf7..966b29d 100644
--- a/SDKs/linux/usr/include/stdlib.h
+++ b/SDKs/linux/usr/include/stdlib.h
@@ -30,5 +30,7 @@
__attribute__((__warn_unused_result__));
void *malloc(size_t) __attribute__((__nothrow__)) __attribute((__malloc__))
__attribute__((__warn_unused_result__));
+void *realloc(void *, size_t) __attribute__((__nothrow__)) __attribute((__malloc__))
+ __attribute__((__warn_unused_result__));
#endif /* __STDLIB_H__ */
diff --git a/SDKs/linux/usr/include/sys/fcntl.h b/SDKs/linux/usr/include/sys/fcntl.h
new file mode 100644
index 0000000..1512bf9
--- /dev/null
+++ b/SDKs/linux/usr/include/sys/fcntl.h
@@ -0,0 +1,29 @@
+/* ===-- fcntl.h - stub SDK header for compiler-rt --------------------------===
+ *
+ * The LLVM Compiler Infrastructure
+ *
+ * This file is dual licensed under the MIT and the University of Illinois Open
+ * Source Licenses. See LICENSE.TXT for details.
+ *
+ * ===-----------------------------------------------------------------------===
+ *
+ * This is a stub SDK header file. This file is not part of the interface of
+ * this library nor an official version of the appropriate SDK header. It is
+ * intended only to stub the features of this header required by compiler-rt.
+ *
+ * ===-----------------------------------------------------------------------===
+ */
+
+#ifndef _SYS_FCNTL_H_
+#define _SYS_FCNTL_H_
+
+#define O_RDONLY 0x0000
+#define O_WRONLY 0x0001
+#define O_RDWR 0x0002
+#define O_ACCMODE 0x0003
+
+#define O_CREAT 0x0200
+
+int open(const char *, int, ...);
+
+#endif /* _SYS_FCNTL_H_ */
diff --git a/SDKs/linux/usr/include/sys/mman.h b/SDKs/linux/usr/include/sys/mman.h
index 7c4d051..bfb7f8b 100644
--- a/SDKs/linux/usr/include/sys/mman.h
+++ b/SDKs/linux/usr/include/sys/mman.h
@@ -19,10 +19,28 @@
typedef __SIZE_TYPE__ size_t;
-#define PROT_READ 0x1
-#define PROT_WRITE 0x2
-#define PROT_EXEC 0x4
+#define PROT_NONE 0x00
+#define PROT_READ 0x01
+#define PROT_WRITE 0x02
+#define PROT_EXEC 0x04
+#define MAP_SHARED 0x0001
+#define MAP_PRIVATE 0x0002
+
+#define MAP_FILE 0x0000
+#define MAP_ANON 0x1000
+
+#define MS_ASYNC 0x0001
+#define MS_INVALIDATE 0x0002
+#define MS_SYNC 0x0010
+
+extern void *mmap(void *addr, size_t len, int prot, int flags, int fd,
+ long long offset)
+ __attribute__((__nothrow__));
+extern int munmap(void *addr, size_t len)
+ __attribute__((__nothrow__));
+extern int msync(void *addr, size_t len, int flags)
+ __attribute__((__nothrow__));
extern int mprotect (void *__addr, size_t __len, int __prot)
__attribute__((__nothrow__));