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| /* SPDX-License-Identifier: GPL-2.0 */
| /*---------------------------------------------------------------------------+
| | round_Xsig.S |
| | |
| | Copyright (C) 1992,1993,1994,1995 |
| | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, |
| | Australia. E-mail billm@jacobi.maths.monash.edu.au |
| | |
| | Normalize and round a 12 byte quantity. |
| | Call from C as: |
| | int round_Xsig(Xsig *n) |
| | |
| | Normalize a 12 byte quantity. |
| | Call from C as: |
| | int norm_Xsig(Xsig *n) |
| | |
| | Each function returns the size of the shift (nr of bits). |
| | |
| +---------------------------------------------------------------------------*/
| .file "round_Xsig.S"
|
| #include "fpu_emu.h"
|
|
| .text
| SYM_FUNC_START(round_Xsig)
| pushl %ebp
| movl %esp,%ebp
| pushl %ebx /* Reserve some space */
| pushl %ebx
| pushl %esi
|
| movl PARAM1,%esi
|
| movl 8(%esi),%edx
| movl 4(%esi),%ebx
| movl (%esi),%eax
|
| movl $0,-4(%ebp)
|
| orl %edx,%edx /* ms bits */
| js L_round /* Already normalized */
| jnz L_shift_1 /* Shift left 1 - 31 bits */
|
| movl %ebx,%edx
| movl %eax,%ebx
| xorl %eax,%eax
| movl $-32,-4(%ebp)
|
| /* We need to shift left by 1 - 31 bits */
| L_shift_1:
| bsrl %edx,%ecx /* get the required shift in %ecx */
| subl $31,%ecx
| negl %ecx
| subl %ecx,-4(%ebp)
| shld %cl,%ebx,%edx
| shld %cl,%eax,%ebx
| shl %cl,%eax
|
| L_round:
| testl $0x80000000,%eax
| jz L_exit
|
| addl $1,%ebx
| adcl $0,%edx
| jnz L_exit
|
| movl $0x80000000,%edx
| incl -4(%ebp)
|
| L_exit:
| movl %edx,8(%esi)
| movl %ebx,4(%esi)
| movl %eax,(%esi)
|
| movl -4(%ebp),%eax
|
| popl %esi
| popl %ebx
| leave
| RET
| SYM_FUNC_END(round_Xsig)
|
|
|
| SYM_FUNC_START(norm_Xsig)
| pushl %ebp
| movl %esp,%ebp
| pushl %ebx /* Reserve some space */
| pushl %ebx
| pushl %esi
|
| movl PARAM1,%esi
|
| movl 8(%esi),%edx
| movl 4(%esi),%ebx
| movl (%esi),%eax
|
| movl $0,-4(%ebp)
|
| orl %edx,%edx /* ms bits */
| js L_n_exit /* Already normalized */
| jnz L_n_shift_1 /* Shift left 1 - 31 bits */
|
| movl %ebx,%edx
| movl %eax,%ebx
| xorl %eax,%eax
| movl $-32,-4(%ebp)
|
| orl %edx,%edx /* ms bits */
| js L_n_exit /* Normalized now */
| jnz L_n_shift_1 /* Shift left 1 - 31 bits */
|
| movl %ebx,%edx
| movl %eax,%ebx
| xorl %eax,%eax
| addl $-32,-4(%ebp)
| jmp L_n_exit /* Might not be normalized,
| but shift no more. */
|
| /* We need to shift left by 1 - 31 bits */
| L_n_shift_1:
| bsrl %edx,%ecx /* get the required shift in %ecx */
| subl $31,%ecx
| negl %ecx
| subl %ecx,-4(%ebp)
| shld %cl,%ebx,%edx
| shld %cl,%eax,%ebx
| shl %cl,%eax
|
| L_n_exit:
| movl %edx,8(%esi)
| movl %ebx,4(%esi)
| movl %eax,(%esi)
|
| movl -4(%ebp),%eax
|
| popl %esi
| popl %ebx
| leave
| RET
| SYM_FUNC_END(norm_Xsig)
|
|
