From: Jiangshan Yi <[email protected]>
Fix the following coccicheck warning:
lib/lzo/lzo1x_compress.c:54: WARNING opportunity for min().
lib/lzo/lzo1x_compress.c:329: WARNING opportunity for min().
min() and min_t() macro is defined in include/linux/minmax.h. It avoids
multiple evaluations of the arguments when non-constant and performs
strict type-checking.
Signed-off-by: Jiangshan Yi <[email protected]>
---
lib/lzo/lzo1x_compress.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/lib/lzo/lzo1x_compress.c b/lib/lzo/lzo1x_compress.c
index 76758e9296ba..9d31e7126606 100644
--- a/lib/lzo/lzo1x_compress.c
+++ b/lib/lzo/lzo1x_compress.c
@@ -50,9 +50,7 @@ lzo1x_1_do_compress(const unsigned char *in, size_t in_len,
if (dv == 0 && bitstream_version) {
const unsigned char *ir = ip + 4;
- const unsigned char *limit = ip_end
- < (ip + MAX_ZERO_RUN_LENGTH + 1)
- ? ip_end : ip + MAX_ZERO_RUN_LENGTH + 1;
+ const unsigned char *limit = min(ip_end, ip + MAX_ZERO_RUN_LENGTH + 1);
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && \
defined(LZO_FAST_64BIT_MEMORY_ACCESS)
u64 dv64;
@@ -326,7 +324,7 @@ static int lzogeneric1x_1_compress(const unsigned char *in, size_t in_len,
data_start = op;
while (l > 20) {
- size_t ll = l <= (m4_max_offset + 1) ? l : (m4_max_offset + 1);
+ size_t ll = min_t(size_t, l, m4_max_offset + 1);
uintptr_t ll_end = (uintptr_t) ip + ll;
if ((ll_end + ((t + ll) >> 5)) <= ll_end)
break;
--
2.25.1
Jiangshan Yi <[email protected]> writes:
> From: Jiangshan Yi <[email protected]>
>
> Fix the following coccicheck warning:
>
> lib/lzo/lzo1x_compress.c:54: WARNING opportunity for min().
> lib/lzo/lzo1x_compress.c:329: WARNING opportunity for min().
>
> min() and min_t() macro is defined in include/linux/minmax.h. It avoids
> multiple evaluations of the arguments when non-constant and performs
> strict type-checking.
>
> Signed-off-by: Jiangshan Yi <[email protected]>
> ---
> lib/lzo/lzo1x_compress.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/lib/lzo/lzo1x_compress.c b/lib/lzo/lzo1x_compress.c
> index 76758e9296ba..9d31e7126606 100644
> --- a/lib/lzo/lzo1x_compress.c
> +++ b/lib/lzo/lzo1x_compress.c
> @@ -50,9 +50,7 @@ lzo1x_1_do_compress(const unsigned char *in, size_t in_len,
>
> if (dv == 0 && bitstream_version) {
> const unsigned char *ir = ip + 4;
> - const unsigned char *limit = ip_end
> - < (ip + MAX_ZERO_RUN_LENGTH + 1)
> - ? ip_end : ip + MAX_ZERO_RUN_LENGTH + 1;
> + const unsigned char *limit = min(ip_end, ip + MAX_ZERO_RUN_LENGTH + 1);
> #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && \
> defined(LZO_FAST_64BIT_MEMORY_ACCESS)
> u64 dv64;
> @@ -326,7 +324,7 @@ static int lzogeneric1x_1_compress(const unsigned char *in, size_t in_len,
> data_start = op;
>
> while (l > 20) {
> - size_t ll = l <= (m4_max_offset + 1) ? l : (m4_max_offset + 1);
> + size_t ll = min_t(size_t, l, m4_max_offset + 1);
> uintptr_t ll_end = (uintptr_t) ip + ll;
> if ((ll_end + ((t + ll) >> 5)) <= ll_end)
> break;
So these look like good changes to me, but I am not the maintainer of
this code. Maybe Andrew (copied) would have a spot for this patch?
Thanks,
jon
> From: Jonathan Corbet <[email protected]>
> Sent: 14 July 2022 14:39
> To: Jiangshan Yi
> Cc: [email protected]; [email protected]; Jiangshan Yi; Andrew Morton
> Subject: Re: [PATCH] lib/lzo/lzo1x_compress.c: replace ternary operator with min() and min_t()
>
> Jiangshan Yi <[email protected]> writes:
>
> > From: Jiangshan Yi <[email protected]>
> >
> > Fix the following coccicheck warning:
> >
> > lib/lzo/lzo1x_compress.c:54: WARNING opportunity for min().
> > lib/lzo/lzo1x_compress.c:329: WARNING opportunity for min().
> >
> > min() and min_t() macro is defined in include/linux/minmax.h. It avoids
> > multiple evaluations of the arguments when non-constant and performs
> > strict type-checking.
> >
> > Signed-off-by: Jiangshan Yi <[email protected]>
> > ---
> > lib/lzo/lzo1x_compress.c | 6 ++----
> > 1 file changed, 2 insertions(+), 4 deletions(-)
> >
> > diff --git a/lib/lzo/lzo1x_compress.c b/lib/lzo/lzo1x_compress.c
> > index 76758e9296ba..9d31e7126606 100644
> > --- a/lib/lzo/lzo1x_compress.c
> > +++ b/lib/lzo/lzo1x_compress.c
> > @@ -50,9 +50,7 @@ lzo1x_1_do_compress(const unsigned char *in, size_t in_len,
> >
> > if (dv == 0 && bitstream_version) {
> > const unsigned char *ir = ip + 4;
> > - const unsigned char *limit = ip_end
> > - < (ip + MAX_ZERO_RUN_LENGTH + 1)
> > - ? ip_end : ip + MAX_ZERO_RUN_LENGTH + 1;
> > + const unsigned char *limit = min(ip_end, ip + MAX_ZERO_RUN_LENGTH + 1);
> > #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && > defined(LZO_FAST_64BIT_MEMORY_ACCESS)
> > u64 dv64;
> > @@ -326,7 +324,7 @@ static int lzogeneric1x_1_compress(const unsigned char *in, size_t in_len,
> > data_start = op;
> >
> > while (l > 20) {
> > - size_t ll = l <= (m4_max_offset + 1) ? l : (m4_max_offset + 1);
> > + size_t ll = min_t(size_t, l, m4_max_offset + 1);
> > uintptr_t ll_end = (uintptr_t) ip + ll;
> > if ((ll_end + ((t + ll) >> 5)) <= ll_end)
> > break;
>
> So these look like good changes to me, but I am not the maintainer of
> this code. Maybe Andrew (copied) would have a spot for this patch?
>
> Thanks,
>
> jon
This looks good to me. I've given it a quick test and it appears to function properly.
Dave
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