65 lines
		
	
	
	
		
			2 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
		
		
			
		
	
	
			65 lines
		
	
	
	
		
			2 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
|   | ;;  Copyright 2010  Free Software Foundation, Inc.
 | ||
|  | ;;  Contributed by Bernd Schmidt <bernds@codesourcery.com>.
 | ||
|  | ;;
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|  | ;; This program is free software; you can redistribute it and/or modify
 | ||
|  | ;; it under the terms of the GNU General Public License as published by
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|  | ;; the Free Software Foundation; either version 2 of the License, or
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|  | ;; (at your option) any later version.
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|  | ;;
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|  | ;; This program is distributed in the hope that it will be useful,
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|  | ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  | ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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|  | ;; GNU General Public License for more details.
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|  | ;;
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|  | ;; You should have received a copy of the GNU General Public License
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|  | ;; along with this program; if not, write to the Free Software
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|  | ;; Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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|  | 
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|  | #include <linux/linkage.h> | ||
|  | 
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|  | 	;; ABI considerations for the divide functions
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|  | 	;; The following registers are call-used:
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|  | 	;; __c6xabi_divi A0,A1,A2,A4,A6,B0,B1,B2,B4,B5
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|  | 	;; __c6xabi_divu A0,A1,A2,A4,A6,B0,B1,B2,B4
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|  | 	;; __c6xabi_remi A1,A2,A4,A5,A6,B0,B1,B2,B4
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|  | 	;; __c6xabi_remu A1,A4,A5,A7,B0,B1,B2,B4
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|  | 	;;
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|  | 	;; In our implementation, divu and remu are leaf functions,
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|  | 	;; while both divi and remi call into divu.
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|  | 	;; A0 is not clobbered by any of the functions.
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|  | 	;; divu does not clobber B2 either, which is taken advantage of
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|  | 	;; in remi.
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|  | 	;; divi uses B5 to hold the original return address during
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|  | 	;; the call to divu.
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|  | 	;; remi uses B2 and A5 to hold the input values during the
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|  | 	;; call to divu.  It stores B3 in on the stack.
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|  | 
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|  | 	.text | ||
|  | 
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|  | 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 | ||
|  | 
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|  |    [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) |