projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 1a59d1b8 | 1 | ;; SPDX-License-Identifier: GPL-2.0-or-later |
| 09831ca7 AJ |
2 | ;; Copyright 2010 Free Software Foundation, Inc. |
| 3 | ;; Contributed by Bernd Schmidt <bernds@codesourcery.com>. | |
| 4 | ;; | |
| 09831ca7 AJ |
5 | |
| 6 | #include <linux/linkage.h> | |
| 7 | ||
| 8 | ;; ABI considerations for the divide functions | |
| 9 | ;; The following registers are call-used: | |
| 10 | ;; __c6xabi_divi A0,A1,A2,A4,A6,B0,B1,B2,B4,B5 | |
| 11 | ;; __c6xabi_divu A0,A1,A2,A4,A6,B0,B1,B2,B4 | |
| 12 | ;; __c6xabi_remi A1,A2,A4,A5,A6,B0,B1,B2,B4 | |
| 13 | ;; __c6xabi_remu A1,A4,A5,A7,B0,B1,B2,B4 | |
| 14 | ;; | |
| 15 | ;; In our implementation, divu and remu are leaf functions, | |
| 16 | ;; while both divi and remi call into divu. | |
| 17 | ;; A0 is not clobbered by any of the functions. | |
| 18 | ;; divu does not clobber B2 either, which is taken advantage of | |
| 19 | ;; in remi. | |
| 20 | ;; divi uses B5 to hold the original return address during | |
| 21 | ;; the call to divu. | |
| 22 | ;; remi uses B2 and A5 to hold the input values during the | |
| 23 | ;; call to divu. It stores B3 in on the stack. | |
| 24 | ||
| 25 | .text | |
| 26 | ||
| 27 | ENTRY(__c6xabi_remi) | |
| 28 | stw .d2t2 B3, *B15--[2] | |
| 29 | || cmpgt .l1 0, A4, A1 | |
| 30 | || cmpgt .l2 0, B4, B2 | |
| 31 | || mv .s1 A4, A5 | |
| 32 | || call .s2 __c6xabi_divu | |
| 33 | ||
| 34 | [A1] neg .l1 A4, A4 | |
| 35 | || [B2] neg .l2 B4, B4 | |
| 36 | || xor .s2x B2, A1, B0 | |
| 37 | || mv .d2 B4, B2 | |
| 38 | ||
| 39 | [B0] addkpc .s2 _divu_ret_1, B3, 1 | |
| 40 | [!B0] addkpc .s2 _divu_ret_2, B3, 1 | |
| 41 | nop 2 | |
| 42 | _divu_ret_1: | |
| 43 | neg .l1 A4, A4 | |
| 44 | _divu_ret_2: | |
| 45 | ldw .d2t2 *++B15[2], B3 | |
| 46 | ||
| 47 | mpy32 .m1x A4, B2, A6 | |
| 48 | nop 3 | |
| 49 | ret .s2 B3 | |
| 50 | sub .l1 A5, A6, A4 | |
| 51 | nop 4 | |
| 52 | ENDPROC(__c6xabi_remi) |