modes/asm/ghashv8-armx.pl: modulo-schedule loop.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4830)

diff --git a/crypto/modes/asm/ghashv8-armx.pl b/crypto/modes/asm/ghashv8-armx.pl
index ef7c74798de562613d2ee7180c5dcab9e62ab452..2498a1d646984a7edc223d049e7015bbea050652 100644 (file)
--- a/crypto/modes/asm/ghashv8-armx.pl
+++ b/crypto/modes/asm/ghashv8-armx.pl
@@ -423,10 +423,7 @@ gcm_ghash_v8_4x:
 #ifndef __ARMEB__
        vrev64.8        $Xl,$Xl
 #endif
-       b               .Loop4x
 
-.align 4
-.Loop4x:
        vld1.64         {$I0-$j3},[$inp],#64
 #ifndef __ARMEB__
        vrev64.8        $j1,$j1
@@ -461,6 +458,13 @@ gcm_ghash_v8_4x:
        veor            $Yh,$Yh,$I1
        veor            $Ym,$Ym,$j1
 
+       subs            $len,$len,#64
+       b.eq            .Ltail4x
+
+       b               .Loop4x
+
+.align 4
+.Loop4x:
        veor            $t0,$I0,$Xl
        vext.8          $IN,$t0,$t0,#8
 
@@ -489,9 +493,72 @@ gcm_ghash_v8_4x:
        veor            $Xl,$Xl,$t2
        vext.8          $Xl,$Xl,$Xl,#8
 
+        vld1.64        {$I0-$j3},[$inp],#64
+#ifndef __ARMEB__
+        vrev64.8       $j1,$j1
+        vrev64.8       $j2,$j2
+        vrev64.8       $j3,$j3
+        vrev64.8       $I0,$I0
+#endif
+        vext.8         $I3,$j3,$j3,#8
+        vext.8         $I2,$j2,$j2,#8
+        vext.8         $I1,$j1,$j1,#8
+
+        vpmull.p64     $Yl,$H,$I3              @ H·Ii+3
+        veor           $j3,$j3,$I3
+        vpmull2.p64    $Yh,$H,$I3
+        vpmull.p64     $Ym,$Hhl,$j3
+
+        vpmull.p64     $t0,$H2,$I2             @ H^2·Ii+2
+        veor           $j2,$j2,$I2
+        vpmull2.p64    $I2,$H2,$I2
+        vpmull2.p64    $j2,$Hhl,$j2
+
+        veor           $Yl,$Yl,$t0
+        veor           $Yh,$Yh,$I2
+        veor           $Ym,$Ym,$j2
+
+        vpmull.p64     $j3,$H3,$I1             @ H^3·Ii+1
+        veor           $j1,$j1,$I1
+        vpmull2.p64    $I1,$H3,$I1
+        vpmull.p64     $j1,$H34,$j1
+
+        veor           $Yl,$Yl,$j3
+        veor           $Yh,$Yh,$I1
+        veor           $Ym,$Ym,$j1
+
        subs            $len,$len,#64
        b.ne            .Loop4x
 
+.Ltail4x:
+       veor            $t0,$I0,$Xl
+       vext.8          $IN,$t0,$t0,#8
+
+       vpmull.p64      $Xl,$H4,$IN             @ H^4·(Xi+Ii)
+       veor            $t0,$t0,$IN
+       vpmull2.p64     $Xh,$H4,$IN
+       vpmull2.p64     $Xm,$H34,$t0
+
+       veor            $Xl,$Xl,$Yl
+       veor            $Xh,$Xh,$Yh
+       veor            $Xm,$Xm,$Ym
+
+       vext.8          $t1,$Xl,$Xh,#8          @ Karatsuba post-processing
+       veor            $t2,$Xl,$Xh
+       veor            $Xm,$Xm,$t1
+       veor            $Xm,$Xm,$t2
+
+       vpmull.p64      $t2,$Xl,$xC2            @ 1st phase of reduction
+       vmov            $Xh#lo,$Xm#hi           @ Xh|Xm - 256-bit result
+       vmov            $Xm#hi,$Xl#lo           @ Xm is rotated Xl
+       veor            $Xl,$Xm,$t2
+
+       vext.8          $t2,$Xl,$Xl,#8          @ 2nd phase of reduction
+       vpmull.p64      $Xl,$Xl,$xC2
+       veor            $t2,$t2,$Xh
+       veor            $Xl,$Xl,$t2
+       vext.8          $Xl,$Xl,$Xl,#8
+
 #ifndef __ARMEB__
        vrev64.8        $Xl,$Xl
 #endif