1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
| ;; SPDX-License-Identifier: GPL-2.0-or-later
| ;; Copyright 2010 Free Software Foundation, Inc.
| ;; Contributed by Bernd Schmidt <bernds@codesourcery.com>.
| ;;
|
| #include <linux/linkage.h>
|
| ;; ABI considerations for the divide functions
| ;; The following registers are call-used:
| ;; __c6xabi_divi A0,A1,A2,A4,A6,B0,B1,B2,B4,B5
| ;; __c6xabi_divu A0,A1,A2,A4,A6,B0,B1,B2,B4
| ;; __c6xabi_remi A1,A2,A4,A5,A6,B0,B1,B2,B4
| ;; __c6xabi_remu A1,A4,A5,A7,B0,B1,B2,B4
| ;;
| ;; In our implementation, divu and remu are leaf functions,
| ;; while both divi and remi call into divu.
| ;; A0 is not clobbered by any of the functions.
| ;; divu does not clobber B2 either, which is taken advantage of
| ;; in remi.
| ;; divi uses B5 to hold the original return address during
| ;; the call to divu.
| ;; remi uses B2 and A5 to hold the input values during the
| ;; call to divu. It stores B3 in on the stack.
|
| .text
|
| ENTRY(__c6xabi_remi)
| stw .d2t2 B3, *B15--[2]
| || cmpgt .l1 0, A4, A1
| || cmpgt .l2 0, B4, B2
| || mv .s1 A4, A5
| || call .s2 __c6xabi_divu
|
| [A1] neg .l1 A4, A4
| || [B2] neg .l2 B4, B4
| || xor .s2x B2, A1, B0
| || mv .d2 B4, B2
|
| [B0] addkpc .s2 _divu_ret_1, B3, 1
| [!B0] addkpc .s2 _divu_ret_2, B3, 1
| nop 2
| _divu_ret_1:
| neg .l1 A4, A4
| _divu_ret_2:
| ldw .d2t2 *++B15[2], B3
|
| mpy32 .m1x A4, B2, A6
| nop 3
| ret .s2 B3
| sub .l1 A5, A6, A4
| nop 4
| ENDPROC(__c6xabi_remi)
|
|