1 files changed, 52 insertions, 0 deletions

diff --git a/arch/alpha/lib/strcat.S b/arch/alpha/lib/strcat.S
new file mode 100644
index 000000000000..393f50384878
--- /dev/null
+++ b/arch/alpha/lib/strcat.S
@@ -0,0 +1,52 @@
+/*
+ * arch/alpha/lib/strcat.S
+ * Contributed by Richard Henderson (rth@tamu.edu)
+ *
+ * Append a null-terminated string from SRC to DST.
+ */
+
+        .text
+
+        .align 3
+        .globl strcat
+        .ent strcat
+strcat:
+        .frame $30, 0, $26
+        .prologue 0
+
+        mov     $16, $0         # set up return value
+
+        /* Find the end of the string.  */
+
+        ldq_u   $1, 0($16)      # load first quadword (a0 may be misaligned)
+        lda     $2, -1
+        insqh   $2, $16, $2
+        andnot  $16, 7, $16
+        or      $2, $1, $1
+        cmpbge  $31, $1, $2     # bits set iff byte == 0
+        bne     $2, $found
+
+$loop:  ldq     $1, 8($16)
+        addq    $16, 8, $16
+        cmpbge  $31, $1, $2
+        beq     $2, $loop
+
+$found: negq    $2, $3          # clear all but least set bit
+        and     $2, $3, $2
+
+        and     $2, 0xf0, $3    # binary search for that set bit
+        and     $2, 0xcc, $4
+        and     $2, 0xaa, $5
+        cmovne  $3, 4, $3
+        cmovne  $4, 2, $4
+        cmovne  $5, 1, $5
+        addq    $3, $4, $3
+        addq    $16, $5, $16
+        addq    $16, $3, $16
+
+        /* Now do the append.  */
+
+        mov     $26, $23
+        br      __stxcpy
+
+        .end strcat