10x printf speedup.
Android is UTF-8. Don't make everyone pay to convert UTF-8 to ASCII just
so we can recognize '%'. With UTF-8 we can just strchr forwards.
Before:
---------------------------------------------------------------
Benchmark Time CPU Iterations
---------------------------------------------------------------
BM_stdio_printf_literal 1290 ns 1290 ns 442554
BM_stdio_printf_s 1204 ns 1204 ns 582446
BM_stdio_printf_d 1206 ns 1206 ns 578311
BM_stdio_printf_1$s 2263 ns 2263 ns 310002
After:
---------------------------------------------------------------
Benchmark Time CPU Iterations
---------------------------------------------------------------
BM_stdio_printf_literal 178 ns 178 ns 3394001
BM_stdio_printf_s 246 ns 246 ns 2850284
BM_stdio_printf_d 252 ns 252 ns 2778610
BM_stdio_printf_1$s 363 ns 363 ns 1929011
Add missing __find_arguments error checking to the wide variant to match
the regular one.
Also replace various char/wchar_t differences with the macro.
Bug: http://b/67371539
Test: ran tests
Change-Id: I18f122009c22699943ab5d666a98ea594a972c40
diff --git a/libc/stdio/vfwprintf.cpp b/libc/stdio/vfwprintf.cpp
index 38acccf..7235969 100644
--- a/libc/stdio/vfwprintf.cpp
+++ b/libc/stdio/vfwprintf.cpp
@@ -277,7 +277,6 @@
#define MAXINT 0x1000 /* largest integer size (intmax_t) */
int __vfwprintf(FILE* __restrict fp, const wchar_t* __restrict fmt0, __va_list ap) {
- wchar_t* fmt; /* format string */
wchar_t ch; /* character from fmt */
int n, n2, n3; /* handy integers (short term usage) */
wchar_t* cp; /* handy char pointer (short term usage) */
@@ -336,10 +335,12 @@
* below longer.
*/
#define PADSIZE 16 /* pad chunk size */
- static wchar_t blanks[PADSIZE] = { ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ',
- ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ' };
- static wchar_t zeroes[PADSIZE] = { '0', '0', '0', '0', '0', '0', '0', '0',
- '0', '0', '0', '0', '0', '0', '0', '0' };
+ static CHAR_TYPE blanks[PADSIZE] = {
+ ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' '
+ };
+ static CHAR_TYPE zeroes[PADSIZE] = {
+ '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0'
+ };
static const char xdigs_lower[] = "0123456789abcdef";
static const char xdigs_upper[] = "0123456789ABCDEF";
@@ -421,25 +422,28 @@
* Get * arguments, including the form *nn$. Preserve the nextarg
* that the argument can be gotten once the type is determined.
*/
-#define GETASTER(val) \
- n2 = 0; \
- cp = fmt; \
- while (is_digit(*cp)) { \
- APPEND_DIGIT(n2, *cp); \
- cp++; \
- } \
- if (*cp == '$') { \
- int hold = nextarg; \
- if (argtable == NULL) { \
- argtable = statargtable; \
- __find_arguments(fmt0, orgap, &argtable, &argtablesiz); \
- } \
- nextarg = n2; \
- val = GETARG(int); \
- nextarg = hold; \
- fmt = ++cp; \
- } else { \
- val = GETARG(int); \
+#define GETASTER(val) \
+ n2 = 0; \
+ cp = fmt; \
+ while (is_digit(*cp)) { \
+ APPEND_DIGIT(n2, *cp); \
+ cp++; \
+ } \
+ if (*cp == '$') { \
+ int hold = nextarg; \
+ if (argtable == NULL) { \
+ argtable = statargtable; \
+ if (__find_arguments(fmt0, orgap, &argtable, &argtablesiz) == -1) { \
+ ret = -1; \
+ goto error; \
+ } \
+ } \
+ nextarg = n2; \
+ val = GETARG(int); \
+ nextarg = hold; \
+ fmt = ++cp; \
+ } else { \
+ val = GETARG(int); \
}
/*
@@ -451,17 +455,19 @@
((argtable != NULL) ? *((type*)(&argtable[nextarg++])) : (nextarg++, va_arg(ap, type)))
_SET_ORIENTATION(fp, 1);
- /* sorry, fwprintf(read_only_file, "") returns EOF, not 0 */
+
+ // Writing "" to a read only file returns EOF, not 0.
if (cantwrite(fp)) {
errno = EBADF;
- return (EOF);
+ return EOF;
}
- /* optimise fwprintf(stderr) (and other unbuffered Unix files) */
- if ((fp->_flags & (__SNBF | __SWR | __SRW)) == (__SNBF | __SWR) && fp->_file >= 0)
+ // Optimize writes to stderr and other unbuffered files).
+ if ((fp->_flags & (__SNBF | __SWR | __SRW)) == (__SNBF | __SWR) && fp->_file >= 0) {
return (__sbprintf(fp, fmt0, ap));
+ }
- fmt = (wchar_t*)fmt0;
+ CHAR_TYPE* fmt = const_cast<CHAR_TYPE*>(fmt0);
argtable = NULL;
nextarg = 1;
va_copy(orgap, ap);
@@ -540,7 +546,10 @@
nextarg = n;
if (argtable == NULL) {
argtable = statargtable;
- __find_arguments(fmt0, orgap, &argtable, &argtablesiz);
+ if (__find_arguments(fmt0, orgap, &argtable, &argtablesiz) == -1) {
+ ret = -1;
+ goto error;
+ }
}
goto rflag;
}
@@ -572,7 +581,10 @@
nextarg = n;
if (argtable == NULL) {
argtable = statargtable;
- __find_arguments(fmt0, orgap, &argtable, &argtablesiz);
+ if (__find_arguments(fmt0, orgap, &argtable, &argtablesiz) == -1) {
+ ret = -1;
+ goto error;
+ }
}
goto rflag;
}
@@ -1037,12 +1049,10 @@
* used since we are attempting to make snprintf thread safe, and alloca is
* problematic since we have nested functions..)
*/
-static int __find_arguments(const wchar_t* fmt0, va_list ap, union arg** argtable,
+static int __find_arguments(const CHAR_TYPE* fmt0, va_list ap, union arg** argtable,
size_t* argtablesiz) {
- wchar_t* fmt; /* format string */
int ch; /* character from fmt */
int n, n2; /* handy integer (short term usage) */
- wchar_t* cp; /* handy char pointer (short term usage) */
int flags; /* flags as above */
unsigned char* typetable; /* table of types */
unsigned char stattypetable[STATIC_ARG_TBL_SIZE];
@@ -1108,7 +1118,8 @@
} else { \
ADDTYPE(T_INT); \
}
- fmt = (wchar_t*)fmt0;
+ CHAR_TYPE* fmt = const_cast<CHAR_TYPE*>(fmt0);
+ CHAR_TYPE* cp;
typetable = stattypetable;
tablesize = STATIC_ARG_TBL_SIZE;
tablemax = 0;