50 lines
		
	
	
	
		
			1.5 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
		
		
			
		
	
	
			50 lines
		
	
	
	
		
			1.5 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
|   | ;;  Copyright (C) 2010 Texas Instruments Incorporated
 | ||
|  | ;;  Contributed by Mark Salter <msalter@redhat.com>.
 | ||
|  | ;;
 | ||
|  | ;; 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
 | ||
|  | ;; the Free Software Foundation; either version 2 of the License, or
 | ||
|  | ;; (at your option) any later version.
 | ||
|  | ;;
 | ||
|  | ;; This program is distributed in the hope that it will be useful,
 | ||
|  | ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
 | ||
|  | ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 | ||
|  | ;; GNU General Public License for more details.
 | ||
|  | ;;
 | ||
|  | ;; You should have received a copy of the GNU General Public License
 | ||
|  | ;; along with this program; if not, write to the Free Software
 | ||
|  | ;; Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 | ||
|  | 
 | ||
|  | #include <linux/linkage.h> | ||
|  | 
 | ||
|  | 	;; uint64_t __c6xabi_mpyll(uint64_t x, uint64_t y)
 | ||
|  | 	;;
 | ||
|  | 	;; 64x64 multiply
 | ||
|  | 	;; First compute partial results using 32-bit parts of x and y:
 | ||
|  | 	;;
 | ||
|  | 	;;   b63	 b32 b31	  b0
 | ||
|  | 	;;    -----------------------------
 | ||
|  | 	;;    |      1	    |	   0	  |
 | ||
|  | 	;;    -----------------------------
 | ||
|  | 	;;
 | ||
|  | 	;;   P0 = X0*Y0
 | ||
|  | 	;;   P1 = X0*Y1 + X1*Y0
 | ||
|  | 	;;   P2 = X1*Y1
 | ||
|  | 	;;
 | ||
|  | 	;;   result = (P2 << 64) + (P1 << 32) + P0
 | ||
|  | 	;;
 | ||
|  | 	;; Since the result is also 64-bit, we can skip the P2 term.
 | ||
|  | 
 | ||
|  | 	.text | ||
|  | ENTRY(__c6xabi_mpyll) | ||
|  | 	mpy32u	.m1x	A4,B4,A1:A0	; X0*Y0
 | ||
|  | 	b	.s2	B3 | ||
|  |  ||	mpy32u	.m2x	B5,A4,B1:B0	; X0*Y1 (don't need upper 32-bits)
 | ||
|  |  ||	mpy32u	.m1x	A5,B4,A3:A2	; X1*Y0 (don't need upper 32-bits)
 | ||
|  | 	nop | ||
|  | 	nop | ||
|  | 	mv	.s1	A0,A4 | ||
|  | 	add	.l1x	A2,B0,A5 | ||
|  | 	add	.s1	A1,A5,A5 | ||
|  | ENDPROC(__c6xabi_mpyll) |