| ;; 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) |
