chacha/asm/chacha-x86.pl: make it compile on legacy systems.

Usage of $ymm variable is a bit misleading here, it doesn't refer
to %ymm register bank, but rather to VEX instruction encoding,
which AMD XOP code path depends on.

Reviewed-by: Richard Levitte <levitte@openssl.org>

diff --git a/crypto/chacha/asm/chacha-x86.pl b/crypto/chacha/asm/chacha-x86.pl
index 8b9696ff0252a4982cd35b06125e6901ac4455f9..d18663badd7ecd30d1295e3060abd001ce798ff5 100755 (executable)
--- a/crypto/chacha/asm/chacha-x86.pl
+++ b/crypto/chacha/asm/chacha-x86.pl
@@ -437,8 +437,10 @@ my ($ap,$bp,$cp,$dp)=map(($_&~3)+(($_-1)&3),($ai,$bi,$ci,$di));    # previous
 
 &function_begin("ChaCha20_ssse3");
 &set_label("ssse3_shortcut");
+if ($ymm) {
        &test           (&DWP(4,"ebp"),1<<11);          # test XOP bit
        &jnz            (&label("xop_shortcut"));
+}
 
        &mov            ($out,&wparam(0));
        &mov            ($inp,&wparam(1));
@@ -770,7 +772,7 @@ sub SSSE3ROUND {    # critical path is 20 "SIMD ticks" per round
 }
 &asciz ("ChaCha20 for x86, CRYPTOGAMS by <appro\@openssl.org>");
 
-if ($xmm) {
+if ($ymm) {
 my ($xa,$xa_,$xb,$xb_,$xc,$xc_,$xd,$xd_)=map("xmm$_",(0..7));
 my ($out,$inp,$len)=("edi","esi","ecx");