libbb/sha1: optional i686 hardware accelerates hashing

function                                             old     new   delta
sha1_process_block64_shaNI                             -     524    +524
sha1_begin                                            57     114     +57
.rodata                                           104353  104369     +16
static.shaNI                                           -       1      +1
------------------------------------------------------------------------------
(add/remove: 4/0 grow/shrink: 2/0 up/down: 598/0)             Total: 598 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 20 insertions, 1 deletions

diff --git a/libbb/hash_md5_sha.c b/libbb/hash_md5_sha.c
index 4c6904b48..0b3af723a 100644
--- a/libbb/hash_md5_sha.c
+++ b/libbb/hash_md5_sha.c
@@ -1143,6 +1143,25 @@ static void FAST_FUNC sha512_process_block128(sha512_ctx_t *ctx)
 #endif /* NEED_SHA512 */
 
 #if ENABLE_SHA1_HWACCEL
+# if defined(__GNUC__) && defined(__i386__)
+static void cpuid(unsigned *eax, unsigned *ebx, unsigned *ecx, unsigned *edx)
+{
+        asm (
+                "       cpuid\n"
+                : "=a"(*eax), /* Output */
+                  "=b"(*ebx),
+                  "=c"(*ecx),
+                  "=d"(*edx)
+                : "0"(*eax),  /* Input */
+                  "1"(*ebx),
+                  "2"(*ecx),
+                  "3"(*edx)
+                /* No clobbered registers */
+        );
+}
+struct ASM_expects_76_shaNI { char t[1 - 2*(offsetof(sha1_ctx_t, hash) != 76)]; };
+void FAST_FUNC sha1_process_block64_shaNI(sha1_ctx_t *ctx);
+# endif
 # if defined(__GNUC__) && defined(__x86_64__)
 static void cpuid(unsigned *eax, unsigned *ebx, unsigned *ecx, unsigned *edx)
 {
@@ -1174,7 +1193,7 @@ void FAST_FUNC sha1_begin(sha1_ctx_t *ctx)
         ctx->total64 = 0;
         ctx->process_block = sha1_process_block64;
 #if ENABLE_SHA1_HWACCEL
-# if defined(__GNUC__) && defined(__x86_64__)
+# if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
         {
                 static smallint shaNI;
                 if (!shaNI) {