From: Rich Felker Date: Tue, 12 Apr 2011 17:13:27 +0000 (-0400) Subject: optimize ntohl etc. in terms of bswap functions X-Git-Tag: v0.7.8~7 X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=c89862660bd3845ace7977480db3a43dc80475f4;p=oweals%2Fmusl.git optimize ntohl etc. in terms of bswap functions we can do this without violating the namespace now that they are macros/inline functions rather than extern functions. the motivation is that gcc was generating giant, slow, horrible code for the old functions, and now generates a single byte-swapping instruction. --- diff --git a/src/network/htonl.c b/src/network/htonl.c index b21dace0..6622d16c 100644 --- a/src/network/htonl.c +++ b/src/network/htonl.c @@ -1,10 +1,8 @@ #include +#include uint32_t htonl(uint32_t n) { - union { - uint8_t b[4]; - uint32_t i; - } u = { { n>>24, n>>16, n>>8, n } }; - return u.i; + union { int i; char c; } u = { 1 }; + return u.c ? bswap_32(n) : n; } diff --git a/src/network/htons.c b/src/network/htons.c index 522504a5..03a3a1d5 100644 --- a/src/network/htons.c +++ b/src/network/htons.c @@ -1,10 +1,8 @@ #include +#include uint16_t htons(uint16_t n) { - union { - uint8_t b[2]; - uint16_t s; - } u = { { n>>8, n } }; - return u.s; + union { int i; char c; } u = { 1 }; + return u.c ? bswap_16(n) : n; } diff --git a/src/network/ntohl.c b/src/network/ntohl.c index 64379196..d6fce459 100644 --- a/src/network/ntohl.c +++ b/src/network/ntohl.c @@ -1,10 +1,8 @@ #include +#include uint32_t ntohl(uint32_t n) { - union { - uint32_t i; - uint8_t b[4]; - } u = { n }; - return (u.b[0]<<24) | (u.b[1]<<16) | (u.b[2]<<8) | u.b[3]; + union { int i; char c; } u = { 1 }; + return u.c ? bswap_32(n) : n; } diff --git a/src/network/ntohs.c b/src/network/ntohs.c index 3544a479..745cef42 100644 --- a/src/network/ntohs.c +++ b/src/network/ntohs.c @@ -1,10 +1,8 @@ #include +#include uint16_t ntohs(uint16_t n) { - union { - uint16_t s; - uint8_t b[2]; - } u = { n }; - return (u.b[0]<<8) | u.b[1]; + union { int i; char c; } u = { 1 }; + return u.c ? bswap_16(n) : n; }