rc4-x86_64 portability fix.

[openssl.git] / crypto / rc4 / asm / rc4-x86_64.pl

diff --git a/crypto/rc4/asm/rc4-x86_64.pl b/crypto/rc4/asm/rc4-x86_64.pl
index f96df377b5c791565a26181214abb8f8110d9bd8..c2af3109a069eae24fa3a13fa57e9992bbc99f44 100755 (executable)
--- a/crypto/rc4/asm/rc4-x86_64.pl
+++ b/crypto/rc4/asm/rc4-x86_64.pl
@@ -2,8 +2,9 @@
 #
 # ====================================================================
 # Written by Andy Polyakov <appro@fy.chalmers.se> for the OpenSSL
-# project. Rights for redistribution and usage in source and binary
-# forms are granted according to the OpenSSL license.
+# project. The module is, however, dual licensed under OpenSSL and
+# CRYPTOGAMS licenses depending on where you obtain it. For further
+# details see http://www.openssl.org/~appro/cryptogams/.
 # ====================================================================
 #
 # 2.22x RC4 tune-up:-) It should be noted though that my hand [as in
@@ -45,12 +46,26 @@
 # achieves respectful 432MBps on 2.8GHz processor now. For reference.
 # If executed on Xeon, current RC4_CHAR code-path is 2.7x faster than
 # RC4_INT code-path. While if executed on Opteron, it's only 25%
-# slower slower than the RC4_INT one [meaning that if detecting CPU
-# is not desired, then RC4_CHAR code-path should be preferred, as it
-# provides better *all-round* performance].
+# slower than the RC4_INT one [meaning that if CPU µ-arch detection
+# is not implemented, then this final RC4_CHAR code-path should be
+# preferred, as it provides better *all-round* performance].
+
+# Intel Core2 was observed to perform poorly on both code paths:-( It
+# apparently suffers from some kind of partial register stall, which
+# occurs in 64-bit mode only [as virtually identical 32-bit loop was
+# observed to outperform 64-bit one by almost 50%]. Adding two movzb to
+# cloop1 boosts its performance by 80%! This loop appears to be optimal
+# fit for Core2 and therefore the code was modified to skip cloop8 on
+# this CPU.
 
 $output=shift;
-open STDOUT,"| $^X ../perlasm/x86_64-xlate.pl $output";
+
+$0 =~ m/(.*[\/\\])[^\/\\]+$/; $dir=$1;
+( $xlate="${dir}x86_64-xlate.pl" and -f $xlate ) or
+( $xlate="${dir}../../perlasm/x86_64-xlate.pl" and -f $xlate) or
+die "can't locate x86_64-xlate.pl";
+
+open STDOUT,"| $^X $xlate $output";
 
 $dat="%rdi";       # arg1
 $len="%rsi";       # arg2
@@ -152,6 +167,8 @@ $code.=<<___;
        movzb   ($dat,$XX[0]),$TX[0]#d
        test    \$-8,$len
        jz      .Lcloop1
+       cmpl    \$0,260($dat)
+       jnz     .Lcloop1
        push    %rbx
        jmp     .Lcloop8
 .align 16
@@ -184,7 +201,7 @@ $code.=<<___;
        add     $TX[0]#b,$YY#b
        lea     1($XX[0]),$XX[1]
        movzb   ($dat,$YY),$TY#d
-       movzb   $XX[1]#b,$XX[1]
+       movzb   $XX[1]#b,$XX[1]#d
        movzb   ($dat,$XX[1]),$TX[1]#d
        movb    $TX[0]#b,($dat,$YY)
        cmp     $XX[1],$YY
@@ -221,6 +238,8 @@ $code.=<<___;
        movb    $TY#b,($dat,$XX[0])
        add     $TX[0]#b,$TY#b
        add     \$1,$XX[0]#b
+       movzb   $TY#b,$TY#d
+       movzb   $XX[0]#b,$XX[0]#d
        movzb   ($dat,$TY),$TY#d
        movzb   ($dat,$XX[0]),$TX[0]#d
        xorb    ($inp),$TY#b
@@ -233,6 +252,111 @@ $code.=<<___;
 .size  RC4,.-RC4
 ___
 
+$idx="%r8";
+$ido="%r9";
+
+$code.=<<___;
+.extern        OPENSSL_ia32cap_P
+.globl RC4_set_key
+.type  RC4_set_key,\@function,3
+.align 16
+RC4_set_key:
+       lea     8($dat),$dat
+       lea     ($inp,$len),$inp
+       neg     $len
+       mov     $len,%rcx
+       xor     %eax,%eax
+       xor     $ido,$ido
+       xor     %r10,%r10
+       xor     %r11,%r11
+
+       mov     OPENSSL_ia32cap_P(%rip),$idx#d
+       bt      \$20,$idx#d
+       jnc     .Lw1stloop
+       bt      \$30,$idx#d
+       setc    $ido#b
+       mov     $ido#d,260($dat)
+       jmp     .Lc1stloop
+
+.align 16
+.Lw1stloop:
+       mov     %eax,($dat,%rax,4)
+       add     \$1,%al
+       jnc     .Lw1stloop
+
+       xor     $ido,$ido
+       xor     $idx,$idx
+.align 16
+.Lw2ndloop:
+       mov     ($dat,$ido,4),%r10d
+       add     ($inp,$len,1),$idx#b
+       add     %r10b,$idx#b
+       add     \$1,$len
+       mov     ($dat,$idx,4),%r11d
+       cmovz   %rcx,$len
+       mov     %r10d,($dat,$idx,4)
+       mov     %r11d,($dat,$ido,4)
+       add     \$1,$ido#b
+       jnc     .Lw2ndloop
+       jmp     .Lexit_key
+
+.align 16
+.Lc1stloop:
+       mov     %al,($dat,%rax)
+       add     \$1,%al
+       jnc     .Lc1stloop
+
+       xor     $ido,$ido
+       xor     $idx,$idx
+.align 16
+.Lc2ndloop:
+       mov     ($dat,$ido),%r10b
+       add     ($inp,$len),$idx#b
+       add     %r10b,$idx#b
+       add     \$1,$len
+       mov     ($dat,$idx),%r11b
+       jnz     .Lcnowrap
+       mov     %rcx,$len
+.Lcnowrap:
+       mov     %r10b,($dat,$idx)
+       mov     %r11b,($dat,$ido)
+       add     \$1,$ido#b
+       jnc     .Lc2ndloop
+       movl    \$-1,256($dat)
+
+.align 16
+.Lexit_key:
+       xor     %eax,%eax
+       mov     %eax,-8($dat)
+       mov     %eax,-4($dat)
+       ret
+.size  RC4_set_key,.-RC4_set_key
+
+.globl RC4_options
+.type  RC4_options,\@function,0
+.align 16
+RC4_options:
+       .picmeup %rax
+       lea     .Lopts-.(%rax),%rax
+       mov     OPENSSL_ia32cap_P(%rip),%edx
+       bt      \$20,%edx
+       jnc     .Ldone
+       add     \$12,%rax
+       bt      \$30,%edx
+       jnc     .Ldone
+       add     \$13,%rax
+.Ldone:
+       ret
+.align 64
+.Lopts:
+.asciz "rc4(8x,int)"
+.asciz "rc4(8x,char)"
+.asciz "rc4(1x,char)"
+.asciz "RC4 for x86_64, CRYPTOGAMS by <appro\@openssl.org>"
+.align 64
+.size  RC4_options,.-RC4_options
+___
+
 $code =~ s/#([bwd])/$1/gm;
 
 print $code;