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diff --git a/hw/xfree86/os-support/misc/SlowBcopy.S b/hw/xfree86/os-support/misc/SlowBcopy.S
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+/* $XFree86: xc/programs/Xserver/hw/xfree86/os-support/misc/SlowBcopy.S,v 1.1 1999/07/10 07:24:51 dawes Exp $ */
+/*******************************************************************************
+ Copyright 1994 by Glenn G. Lai
+
+ All Rights Reserved
+
+Permission to use, copy, modify, and distribute this software and its
+documentation for any purpose and without fee is hereby granted,
+provided that the above copyr notice appear in all copies and that
+both that copyr notice and this permission notice appear in
+supporting documentation, and that the name of Glenn G. Lai not be
+used in advertising or publicity pertaining to distribution of the
+software without specific, written prior permission.
+
+Glenn G. Lai DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
+ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
+DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
+ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
+WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
+ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
+SOFTWARE.
+
+Glenn G. Lai
+P.O. Box 4314
+Austin, Tx 78765
+glenn@cs.utexas.edu)
+7/21/94
+*******************************************************************************/
+/* $XConsortium: SlowBcopy.s /main/4 1996/02/21 17:40:52 kaleb $ */
+
+/*
+ * Modified from the output generated by GCC
+ *
+ * Create a dependency that should be immune from the effect of register
+ * renaming as is commonly seen in superscalar processors. This should
+ * insert a minimum of 100-ns delays between reads/writes at clock rates
+ * up to 100 MHz---GGL
+ *
+ * Slowbcopy(char *src, char *dst, int count)
+ *
+ */
+
+#include "assyntax.h"
+
+ FILE("SlowBcopy.s")
+
+ AS_BEGIN
+
+gcc2_compiled.:
+___gnu_compiled_c:
+
+ GLOBL GLNAME(xf86SlowBcopy)
+
+ SEG_TEXT
+ ALIGNTEXT4
+GLNAME(xf86SlowBcopy):
+ PUSH_L (EBP)
+ MOV_L (ESP,EBP)
+ PUSH_L (ESI)
+ PUSH_L (EBX)
+ MOV_L (REGOFF(8,EBP),ECX)
+ MOV_L (REGOFF(12,EBP),EDX)
+ MOV_L (REGOFF(16,EBP),ESI)
+ XOR_L (EAX,EAX)
+ CMP_L (ESI,EAX)
+ JGE (L3)
+
+ ALIGNTEXT4
+L5:
+ MOV_B (REGIND(ECX),BL)
+
+ MOV_B (BL, BH)
+ MOV_B (BH, BL)
+ MOV_B (BL, BH)
+ MOV_B (BH, BL)
+ MOV_B (BL, BH)
+ MOV_B (BH, BL)
+ MOV_B (BL, BH)
+ MOV_B (BH, BL)
+ MOV_B (BL, BH)
+ MOV_B (BH, BL)
+
+ MOV_B (BL,REGIND(EDX))
+
+ INC_L (ECX)
+ DEC_L (ECX)
+ INC_L (ECX)
+ DEC_L (ECX)
+ INC_L (ECX)
+ DEC_L (ECX)
+ INC_L (ECX)
+ DEC_L (ECX)
+ INC_L (ECX)
+ DEC_L (ECX)
+
+ INC_L (ECX)
+ INC_L (EDX)
+ INC_L (EAX)
+ CMP_L (ESI,EAX)
+ JL (L5)
+L3:
+ LEA_L (REGOFF(-8,EBP),ESP)
+ POP_L (EBX)
+ POP_L (ESI)
+ MOV_L (EBP,ESP)
+ POP_L (EBP)
+ RET
+