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diff --git a/arch/alpha/lib/ev67-strncat.S b/arch/alpha/lib/ev67-strncat.S
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+++ b/arch/alpha/lib/ev67-strncat.S
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+/*
+ * arch/alpha/lib/ev67-strncat.S
+ * 21264 version contributed by Rick Gorton <rick.gorton@api-networks.com>
+ *
+ * Append no more than COUNT characters from the null-terminated string SRC
+ * to the null-terminated string DST.  Always null-terminate the new DST.
+ *
+ * This differs slightly from the semantics in libc in that we never write
+ * past count, whereas libc may write to count+1.  This follows the generic
+ * implementation in lib/string.c and is, IMHO, more sensible.
+ *
+ * Much of the information about 21264 scheduling/coding comes from:
+ *      Compiler Writer's Guide for the Alpha 21264
+ *      abbreviated as 'CWG' in other comments here
+ *      ftp.digital.com/pub/Digital/info/semiconductor/literature/dsc-library.html
+ * Scheduling notation:
+ *      E       - either cluster
+ *      U       - upper subcluster; U0 - subcluster U0; U1 - subcluster U1
+ *      L       - lower subcluster; L0 - subcluster L0; L1 - subcluster L1
+ * Try not to change the actual algorithm if possible for consistency.
+ */
+
+
+        .text
+
+        .align 4
+        .globl strncat
+        .ent strncat
+strncat:
+        .frame $30, 0, $26
+        .prologue 0
+
+        mov     $16, $0         # set up return value
+        beq     $18, $zerocount # U :
+        /* Find the end of the string.  */
+        ldq_u   $1, 0($16)      # L : load first quadword ($16 may be misaligned)
+        lda     $2, -1($31)     # E :
+
+        insqh   $2, $0, $2      # U :
+        andnot  $16, 7, $16     # E :
+        nop                     # E :
+        or      $2, $1, $1      # E :
+
+        nop                     # E :
+        nop                     # E :
+        cmpbge  $31, $1, $2     # E : bits set iff byte == 0
+        bne     $2, $found      # U :
+
+$loop:  ldq     $1, 8($16)      # L :
+        addq    $16, 8, $16     # E :
+        cmpbge  $31, $1, $2     # E :
+        beq     $2, $loop       # U :
+
+$found: cttz    $2, $3          # U0 :
+        addq    $16, $3, $16    # E :
+        nop                     # E :
+        bsr     $23, __stxncpy  # L0 :/* Now do the append.  */
+
+        /* Worry about the null termination.  */
+
+        zapnot  $1, $27, $2     # U : was last byte a null?
+        cmplt   $27, $24, $5    # E : did we fill the buffer completely?
+        bne     $2, 0f          # U :
+        ret                     # L0 :
+
+0:      or      $5, $18, $2     # E :
+        nop
+        bne     $2, 2f          # U :
+        and     $24, 0x80, $3   # E : no zero next byte
+
+        nop                     # E :
+        bne     $3, 1f          # U :
+        /* Here there are bytes left in the current word.  Clear one.  */
+        addq    $24, $24, $24   # E : end-of-count bit <<= 1
+        nop                     # E :
+
+2:      zap     $1, $24, $1     # U :
+        nop                     # E :
+        stq_u   $1, 0($16)      # L :
+        ret                     # L0 :
+
+1:      /* Here we must clear the first byte of the next DST word */
+        stb     $31, 8($16)     # L :
+        nop                     # E :
+        nop                     # E :
+        ret                     # L0 :
+
+$zerocount:
+        nop                     # E :
+        nop                     # E :
+        nop                     # E :
+        ret                     # L0 :
+
+        .end strncat