--- /dev/null
+/* mc68020 __gmpn_lshift -- Shift left a low-level natural-number integer.
+
+Copyright (C) 1996, 1999, 2000 Free Software Foundation, Inc.
+
+This file is part of the GNU MP Library.
+
+The GNU MP Library is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 2.1 of the License, or (at your
+option) any later version.
+
+The GNU MP Library is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
+License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with the GNU MP Library; see the file COPYING.LIB. If not, write to
+the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+MA 02111-1307, USA. */
+
+/*
+ INPUT PARAMETERS
+ res_ptr (sp + 4)
+ s_ptr (sp + 8)
+ s_size (sp + 16)
+ cnt (sp + 12)
+*/
+
+#include "asm-syntax.h"
+
+#define res_ptr a1
+#define s_ptr a0
+#define s_size d6
+#define cnt d4
+
+ TEXT
+ ALIGN
+ GLOBL C_SYMBOL_NAME(__gmpn_lshift)
+
+C_SYMBOL_NAME(__gmpn_lshift:)
+PROLOG(__gmpn_lshift)
+
+/* Save used registers on the stack. */
+ moveml R(d2)-R(d6)/R(a2),MEM_PREDEC(sp)
+
+/* Copy the arguments to registers. */
+ movel MEM_DISP(sp,28),R(res_ptr)
+ movel MEM_DISP(sp,32),R(s_ptr)
+ movel MEM_DISP(sp,36),R(s_size)
+ movel MEM_DISP(sp,40),R(cnt)
+
+ moveql #1,R(d5)
+ cmpl R(d5),R(cnt)
+ bne L(Lnormal)
+ cmpl R(s_ptr),R(res_ptr)
+ bls L(Lspecial) /* jump if s_ptr >= res_ptr */
+#if (defined (__mc68020__) || defined (__NeXT__) || defined(mc68020))
+ lea MEM_INDX1(s_ptr,s_size,l,4),R(a2)
+#else /* not mc68020 */
+ movel R(s_size),R(d0)
+ asll #2,R(d0)
+ lea MEM_INDX(s_ptr,d0,l),R(a2)
+#endif
+ cmpl R(res_ptr),R(a2)
+ bls L(Lspecial) /* jump if res_ptr >= s_ptr + s_size */
+
+L(Lnormal:)
+ moveql #32,R(d5)
+ subl R(cnt),R(d5)
+
+#if (defined (__mc68020__) || defined (__NeXT__) || defined(mc68020))
+ lea MEM_INDX1(s_ptr,s_size,l,4),R(s_ptr)
+ lea MEM_INDX1(res_ptr,s_size,l,4),R(res_ptr)
+#else /* not mc68000 */
+ movel R(s_size),R(d0)
+ asll #2,R(d0)
+ addl R(s_size),R(s_ptr)
+ addl R(s_size),R(res_ptr)
+#endif
+ movel MEM_PREDEC(s_ptr),R(d2)
+ movel R(d2),R(d0)
+ lsrl R(d5),R(d0) /* compute carry limb */
+
+ lsll R(cnt),R(d2)
+ movel R(d2),R(d1)
+ subql #1,R(s_size)
+ beq L(Lend)
+ lsrl #1,R(s_size)
+ bcs L(L1)
+ subql #1,R(s_size)
+
+L(Loop:)
+ movel MEM_PREDEC(s_ptr),R(d2)
+ movel R(d2),R(d3)
+ lsrl R(d5),R(d3)
+ orl R(d3),R(d1)
+ movel R(d1),MEM_PREDEC(res_ptr)
+ lsll R(cnt),R(d2)
+L(L1:)
+ movel MEM_PREDEC(s_ptr),R(d1)
+ movel R(d1),R(d3)
+ lsrl R(d5),R(d3)
+ orl R(d3),R(d2)
+ movel R(d2),MEM_PREDEC(res_ptr)
+ lsll R(cnt),R(d1)
+
+ dbf R(s_size),L(Loop)
+ subl #0x10000,R(s_size)
+ bcc L(Loop)
+
+L(Lend:)
+ movel R(d1),MEM_PREDEC(res_ptr) /* store least significant limb */
+
+/* Restore used registers from stack frame. */
+ moveml MEM_POSTINC(sp),R(d2)-R(d6)/R(a2)
+ rts
+
+/* We loop from least significant end of the arrays, which is only
+ permissable if the source and destination don't overlap, since the
+ function is documented to work for overlapping source and destination. */
+
+L(Lspecial:)
+ clrl R(d0) /* initialize carry */
+ eorw #1,R(s_size)
+ lsrl #1,R(s_size)
+ bcc L(LL1)
+ subql #1,R(s_size)
+
+L(LLoop:)
+ movel MEM_POSTINC(s_ptr),R(d2)
+ addxl R(d2),R(d2)
+ movel R(d2),MEM_POSTINC(res_ptr)
+L(LL1:)
+ movel MEM_POSTINC(s_ptr),R(d2)
+ addxl R(d2),R(d2)
+ movel R(d2),MEM_POSTINC(res_ptr)
+
+ dbf R(s_size),L(LLoop)
+ addxl R(d0),R(d0) /* save cy in lsb */
+ subl #0x10000,R(s_size)
+ bcs L(LLend)
+ lsrl #1,R(d0) /* restore cy */
+ bra L(LLoop)
+
+L(LLend:)
+/* Restore used registers from stack frame. */
+ moveml MEM_POSTINC(sp),R(d2)-R(d6)/R(a2)
+ rts
+EPILOG(__gmpn_lshift)
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