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| /* SPDX-License-Identifier: GPL-2.0 */
| .file "shr_Xsig.S"
| /*---------------------------------------------------------------------------+
| | shr_Xsig.S |
| | |
| | 12 byte right shift function |
| | |
| | Copyright (C) 1992,1994,1995 |
| | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, |
| | Australia. E-mail billm@jacobi.maths.monash.edu.au |
| | |
| | Call from C as: |
| | void shr_Xsig(Xsig *arg, unsigned nr) |
| | |
| | Extended shift right function. |
| | Fastest for small shifts. |
| | Shifts the 12 byte quantity pointed to by the first arg (arg) |
| | right by the number of bits specified by the second arg (nr). |
| | |
| +---------------------------------------------------------------------------*/
|
| #include "fpu_emu.h"
|
| .text
| SYM_FUNC_START(shr_Xsig)
| push %ebp
| movl %esp,%ebp
| pushl %esi
| movl PARAM2,%ecx
| movl PARAM1,%esi
| cmpl $32,%ecx /* shrd only works for 0..31 bits */
| jnc L_more_than_31
|
| /* less than 32 bits */
| pushl %ebx
| movl (%esi),%eax /* lsl */
| movl 4(%esi),%ebx /* midl */
| movl 8(%esi),%edx /* msl */
| shrd %cl,%ebx,%eax
| shrd %cl,%edx,%ebx
| shr %cl,%edx
| movl %eax,(%esi)
| movl %ebx,4(%esi)
| movl %edx,8(%esi)
| popl %ebx
| popl %esi
| leave
| RET
|
| L_more_than_31:
| cmpl $64,%ecx
| jnc L_more_than_63
|
| subb $32,%cl
| movl 4(%esi),%eax /* midl */
| movl 8(%esi),%edx /* msl */
| shrd %cl,%edx,%eax
| shr %cl,%edx
| movl %eax,(%esi)
| movl %edx,4(%esi)
| movl $0,8(%esi)
| popl %esi
| leave
| RET
|
| L_more_than_63:
| cmpl $96,%ecx
| jnc L_more_than_95
|
| subb $64,%cl
| movl 8(%esi),%eax /* msl */
| shr %cl,%eax
| xorl %edx,%edx
| movl %eax,(%esi)
| movl %edx,4(%esi)
| movl %edx,8(%esi)
| popl %esi
| leave
| RET
|
| L_more_than_95:
| xorl %eax,%eax
| movl %eax,(%esi)
| movl %eax,4(%esi)
| movl %eax,8(%esi)
| popl %esi
| leave
| RET
| SYM_FUNC_END(shr_Xsig)
|
|
