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Re: [Qemu-devel] [PATCH 1/2] cutils: remove one unnecessary pointer oper
From: |
Wei Yang |
Subject: |
Re: [Qemu-devel] [PATCH 1/2] cutils: remove one unnecessary pointer operation |
Date: |
Tue, 11 Jun 2019 22:10:50 +0000 |
User-agent: |
NeoMutt/20170113 (1.7.2) |
On Tue, Jun 11, 2019 at 06:49:54PM +0100, Dr. David Alan Gilbert wrote:
>* Wei Yang (address@hidden) wrote:
>> Since we will not operate on the next address pointed by out, it is not
>> necessary to do addition on it.
>>
>> After removing the operation, the function size reduced 16/18 bytes.
>
>For me with a -O3 it didn't make any difference - the compiler was
>already smart enough to spot it, but it is correct.
>
Ah, you are right.
>
>Reviewed-by: Dr. David Alan Gilbert <address@hidden>
>
>> Signed-off-by: Wei Yang <address@hidden>
>> ---
>> util/cutils.c | 8 ++++----
>> 1 file changed, 4 insertions(+), 4 deletions(-)
>>
>> diff --git a/util/cutils.c b/util/cutils.c
>> index 9aacc422ca..1933a68da5 100644
>> --- a/util/cutils.c
>> +++ b/util/cutils.c
>> @@ -754,11 +754,11 @@ int uleb128_encode_small(uint8_t *out, uint32_t n)
>> {
>> g_assert(n <= 0x3fff);
>> if (n < 0x80) {
>> - *out++ = n;
>> + *out = n;
>> return 1;
>> } else {
>> *out++ = (n & 0x7f) | 0x80;
>> - *out++ = n >> 7;
>> + *out = n >> 7;
>> return 2;
>> }
>> }
>> @@ -766,7 +766,7 @@ int uleb128_encode_small(uint8_t *out, uint32_t n)
>> int uleb128_decode_small(const uint8_t *in, uint32_t *n)
>> {
>> if (!(*in & 0x80)) {
>> - *n = *in++;
>> + *n = *in;
>> return 1;
>> } else {
>> *n = *in++ & 0x7f;
>> @@ -774,7 +774,7 @@ int uleb128_decode_small(const uint8_t *in, uint32_t *n)
>> if (*in & 0x80) {
>> return -1;
>> }
>> - *n |= *in++ << 7;
>> + *n |= *in << 7;
>> return 2;
>> }
>> }
>> --
>> 2.19.1
>>
>--
>Dr. David Alan Gilbert / address@hidden / Manchester, UK
--
Wei Yang
Help you, Help me