RC4 tune-up for Intel P4 core, both 32- and 64-bit ones. As it's

[openssl.git] / crypto / rc4 / asm / rc4-amd64.pl

diff --git a/crypto/rc4/asm/rc4-amd64.pl b/crypto/rc4/asm/rc4-amd64.pl
index cc3f0c0231b8c4ad6c37d58dbd2b8cf4cc0463b1..35e426d561a35a0c117cc3161132c07bb5df8a00 100755 (executable)
--- a/crypto/rc4/asm/rc4-amd64.pl
+++ b/crypto/rc4/asm/rc4-amd64.pl
@@ -25,6 +25,13 @@
 # Latter means that if you want to *estimate* what to expect from
 # *your* CPU, then multiply 54 by 3.3 and clock frequency in GHz.
 
+# Intel P4 EM64T core was found to run the AMD64 code really slow...
+# The only way to achieve comparable performance on P4 is to keep
+# RC4_CHAR. Kind of ironic, huh? As it's apparently impossible to
+# compose blended code, which would perform even within 30% marginal
+# on either AMD and Intel platforms, I implement both cases. See
+# rc4_skey.c for further details...
+
 $output=shift;
 
 $win64a=1 if ($output =~ /win64a.[s|asm]/);
@@ -90,6 +97,8 @@ $code.=<<___;
        add     \$8,$dat
        movl    `&PTR("DWORD:-8[$dat]")`,$XX#d
        movl    `&PTR("DWORD:-4[$dat]")`,$YY#d
+       cmpl    \$-1,`&PTR("DWORD:256[$dat]")`
+       je      .LRC4_CHAR
        test    \$-8,$len
        jz      .Lloop1
 .align 16
@@ -167,6 +176,24 @@ $code.=<<___;
        dec     $len
        jnz     .Lloop1
        jmp     .Lexit
+
+.align 16
+.LRC4_CHAR:
+       inc     $XX#b
+       movzb   `&PTR("BYTE:[$dat+$XX]")`,$TX#d
+       add     $TX#b,$YY#b
+       movzb   `&PTR("BYTE:[$dat+$YY]")`,$TY#d
+       movb    $TX#b,`&PTR("BYTE:[$dat+$YY]")`
+       movb    $TY#b,`&PTR("BYTE:[$dat+$XX]")`
+       add     $TX#b,$TY#b
+       movzb   `&PTR("BYTE:[$dat+$TY]")`,$TY#d
+       xorb    `&PTR("BYTE:[$inp]")`,$TY#b
+       movb    $TY#b,`&PTR("BYTE:[$out]")`
+       inc     $inp
+       inc     $out
+       dec     $len
+       jnz     .LRC4_CHAR
+       jmp     .Lexit
 ___
 $code.=<<___ if (defined($win64a));
 RC4    ENDP
@@ -189,6 +216,8 @@ if (defined($win64a)) {
     $code =~ s/mov[bwlq]/mov/gm;
     $code =~ s/movzb/movzx/gm;
     $code =~ s/repret/DB\t0F3h,0C3h/gm;
+    $code =~ s/cmpl/cmp/gm;
+    $code =~ s/xorb/xor/gm;
 } else {
     $code =~ s/([QD]*WORD|BYTE)://gm;
     $code =~ s/repret/.byte\t0xF3,0xC3/gm;