1*4882a593Smuzhiyun;; SPDX-License-Identifier: GPL-2.0-or-later 2*4882a593Smuzhiyun;; Copyright 2010 Free Software Foundation, Inc. 3*4882a593Smuzhiyun;; Contributed by Bernd Schmidt <bernds@codesourcery.com>. 4*4882a593Smuzhiyun;; 5*4882a593Smuzhiyun 6*4882a593Smuzhiyun#include <linux/linkage.h> 7*4882a593Smuzhiyun 8*4882a593Smuzhiyun ;; ABI considerations for the divide functions 9*4882a593Smuzhiyun ;; The following registers are call-used: 10*4882a593Smuzhiyun ;; __c6xabi_divi A0,A1,A2,A4,A6,B0,B1,B2,B4,B5 11*4882a593Smuzhiyun ;; __c6xabi_divu A0,A1,A2,A4,A6,B0,B1,B2,B4 12*4882a593Smuzhiyun ;; __c6xabi_remi A1,A2,A4,A5,A6,B0,B1,B2,B4 13*4882a593Smuzhiyun ;; __c6xabi_remu A1,A4,A5,A7,B0,B1,B2,B4 14*4882a593Smuzhiyun ;; 15*4882a593Smuzhiyun ;; In our implementation, divu and remu are leaf functions, 16*4882a593Smuzhiyun ;; while both divi and remi call into divu. 17*4882a593Smuzhiyun ;; A0 is not clobbered by any of the functions. 18*4882a593Smuzhiyun ;; divu does not clobber B2 either, which is taken advantage of 19*4882a593Smuzhiyun ;; in remi. 20*4882a593Smuzhiyun ;; divi uses B5 to hold the original return address during 21*4882a593Smuzhiyun ;; the call to divu. 22*4882a593Smuzhiyun ;; remi uses B2 and A5 to hold the input values during the 23*4882a593Smuzhiyun ;; call to divu. It stores B3 in on the stack. 24*4882a593Smuzhiyun 25*4882a593Smuzhiyun 26*4882a593Smuzhiyun .text 27*4882a593Smuzhiyun 28*4882a593SmuzhiyunENTRY(__c6xabi_remu) 29*4882a593Smuzhiyun ;; The ABI seems designed to prevent these functions calling each other, 30*4882a593Smuzhiyun ;; so we duplicate most of the divsi3 code here. 31*4882a593Smuzhiyun mv .s2x A4, B1 32*4882a593Smuzhiyun lmbd .l2 1, B4, B1 33*4882a593Smuzhiyun|| [!B1] b .s2 B3 ; RETURN A 34*4882a593Smuzhiyun|| [!B1] mvk .d2 1, B4 35*4882a593Smuzhiyun 36*4882a593Smuzhiyun mv .l1x B1, A7 37*4882a593Smuzhiyun|| shl .s2 B4, B1, B4 38*4882a593Smuzhiyun 39*4882a593Smuzhiyun cmpltu .l1x A4, B4, A1 40*4882a593Smuzhiyun [!A1] sub .l1x A4, B4, A4 41*4882a593Smuzhiyun shru .s2 B4, 1, B4 42*4882a593Smuzhiyun 43*4882a593Smuzhiyun_remu_loop: 44*4882a593Smuzhiyun cmpgt .l2 B1, 7, B0 45*4882a593Smuzhiyun|| [B1] subc .l1x A4,B4,A4 46*4882a593Smuzhiyun|| [B1] add .s2 -1, B1, B1 47*4882a593Smuzhiyun ;; RETURN A may happen here (note: must happen before the next branch) 48*4882a593Smuzhiyun [B1] subc .l1x A4,B4,A4 49*4882a593Smuzhiyun|| [B1] add .s2 -1, B1, B1 50*4882a593Smuzhiyun|| [B0] b .s1 _remu_loop 51*4882a593Smuzhiyun [B1] subc .l1x A4,B4,A4 52*4882a593Smuzhiyun|| [B1] add .s2 -1, B1, B1 53*4882a593Smuzhiyun [B1] subc .l1x A4,B4,A4 54*4882a593Smuzhiyun|| [B1] add .s2 -1, B1, B1 55*4882a593Smuzhiyun [B1] subc .l1x A4,B4,A4 56*4882a593Smuzhiyun|| [B1] add .s2 -1, B1, B1 57*4882a593Smuzhiyun [B1] subc .l1x A4,B4,A4 58*4882a593Smuzhiyun|| [B1] add .s2 -1, B1, B1 59*4882a593Smuzhiyun [B1] subc .l1x A4,B4,A4 60*4882a593Smuzhiyun|| [B1] add .s2 -1, B1, B1 61*4882a593Smuzhiyun ;; loop backwards branch happens here 62*4882a593Smuzhiyun 63*4882a593Smuzhiyun ret .s2 B3 64*4882a593Smuzhiyun [B1] subc .l1x A4,B4,A4 65*4882a593Smuzhiyun|| [B1] add .s2 -1, B1, B1 66*4882a593Smuzhiyun [B1] subc .l1x A4,B4,A4 67*4882a593Smuzhiyun 68*4882a593Smuzhiyun extu .s1 A4, A7, A4 69*4882a593Smuzhiyun nop 2 70*4882a593SmuzhiyunENDPROC(__c6xabi_remu) 71