On 20/11/2016 15:56, Andre Przywara wrote:
tiny-printf does not know about the "l" modifier so far, which breaks the crash dump on AArch64, because it uses %lx to print the registers. Add an easy way of handling longs correctly.
Signed-off-by: Andre Przywara andre.przywara@arm.com
lib/tiny-printf.c | 43 +++++++++++++++++++++++++++++++++---------- 1 file changed, 33 insertions(+), 10 deletions(-)
diff --git a/lib/tiny-printf.c b/lib/tiny-printf.c index 30ac759..b01099d 100644 --- a/lib/tiny-printf.c +++ b/lib/tiny-printf.c @@ -38,8 +38,8 @@ static void out_dgt(struct printf_info *info, char dgt) info->zs = 1; }
-static void div_out(struct printf_info *info, unsigned int *num,
unsigned int div)+static void div_out(struct printf_info *info, unsigned long *num,
unsigned long div){ unsigned char dgt = 0;
@@ -56,9 +56,9 @@ int _vprintf(struct printf_info *info, const char *fmt, va_list va) { char ch; char *p;
- unsigned int num;
- unsigned long num; char buf[12];
- unsigned int div;
unsigned long div;
while ((ch = *(fmt++))) { if (ch != '%') {
@@ -66,8 +66,12 @@ int _vprintf(struct printf_info *info, const char *fmt, va_list va) } else { bool lz = false; int width = 0;
bool islong = false; ch = *(fmt++);if (ch == '-')ch = *(fmt++);
What does this do? I don't see '-' mentioned in the patch description.
if (ch == '0') { ch = *(fmt++); lz = 1;@@ -80,6 +84,11 @@ int _vprintf(struct printf_info *info, const char *fmt, va_list va) ch = *fmt++; } }
if (ch == 'l') {ch = *(fmt++);islong = true;}info->bf = buf; p = info->bf; info->zs = 0;@@ -89,24 +98,38 @@ int _vprintf(struct printf_info *info, const char *fmt, va_list va) goto abort; case 'u': case 'd':
num = va_arg(va, unsigned int);if (ch == 'd' && (int)num < 0) {num = -(int)num;
div = 1000000000;if (islong) {
Check here if sizeof(long) > 4, so that the whole branch gets optimized away on 32bit.
num = va_arg(va, unsigned long);if (sizeof(long) > 4)div *= div * 10;} else {num = va_arg(va, unsigned int);}if (ch == 'd' && (long)num < 0) {num = -(long)num;
Num is a long now and before. So if you have a 32bit signed input, it will sign extend incorrectly here. You need an additional check
if (islong) num = -(long)num; else num = -(int)num;
Let's hope the compiler on 32bit is smart enough to know that it can combine those two cases :).
out(info, '-'); } if (!num) { out_dgt(info, 0); } else {
for (div = 1000000000; div; div /= 10)
for (; div; div /= 10)
Any particular reason for that change?
div_out(info, &num, div); } break; case 'x':
num = va_arg(va, unsigned int);
if (islong) {
Same comment as above.
Alex
num = va_arg(va, unsigned long);div = 1UL << (sizeof(long) * 8 - 4);} else {num = va_arg(va, unsigned int);div = 0x10000000;} if (!num) { out_dgt(info, 0); } else {
for (div = 0x10000000; div; div /= 0x10)
for (; div; div /= 0x10) div_out(info, &num, div); } break;