/*
   * Copyright (C) 2000 Hewlett-Packard Co
   * Copyright (C) 2000 David Mosberger-Tang <davidm@hpl.hp.com>
   *
   * 32-bit integer division.
   *
   * This code is based on the application note entitled "Divide, Square Root
   * and Remainder Algorithms for the IA-64 Architecture".  This document
   * is available as Intel document number 248725-002 or via the web at
   * http://developer.intel.com/software/opensource/numerics/
   *
   * For more details on the theory behind these algorithms, see "IA-64
   * and Elementary Functions" by Peter Markstein; HP Professional Books
   * (http://www.hp.com/go/retailbooks/)
   */
  
  #include <asm/asmmacro.h>
  
  #ifdef MODULO
  # define OP	mod
  #else
  # define OP	div
  #endif
  
  #ifdef UNSIGNED
  # define SGN	u
  # define EXTEND	zxt4
  # define INT_TO_FP(a,b)	fcvt.xuf.s1 a=b
  # define FP_TO_INT(a,b)	fcvt.fxu.trunc.s1 a=b
  #else
  # define SGN
  # define EXTEND	sxt4
  # define INT_TO_FP(a,b)	fcvt.xf a=b
  # define FP_TO_INT(a,b)	fcvt.fx.trunc.s1 a=b
  #endif
  
  #define PASTE1(a,b)	a##b
  #define PASTE(a,b)	PASTE1(a,b)
  #define NAME		PASTE(PASTE(__,SGN),PASTE(OP,si3))
  
  GLOBAL_ENTRY(NAME)
  	.regstk 2,0,0,0
  	// Transfer inputs to FP registers.
  	mov r2 = 0xffdd			// r2 = -34 + 65535 (fp reg format bias)
  	EXTEND in0 = in0		// in0 = a
  	EXTEND in1 = in1		// in1 = b
  	;;
  	setf.sig f8 = in0
  	setf.sig f9 = in1
  #ifdef MODULO
  	sub in1 = r0, in1		// in1 = -b
  #endif
  	;;
  	// Convert the inputs to FP, to avoid FP software-assist faults.
  	INT_TO_FP(f8, f8)
  	INT_TO_FP(f9, f9)
  	;;
  	setf.exp f7 = r2		// f7 = 2^-34
  	frcpa.s1 f6, p6 = f8, f9	// y0 = frcpa(b)
  	;;
  (p6)	fmpy.s1 f8 = f8, f6		// q0 = a*y0
  (p6)	fnma.s1 f6 = f9, f6, f1		// e0 = -b*y0 + 1 
  	;;
  #ifdef MODULO
  	setf.sig f9 = in1		// f9 = -b
  #endif
  (p6)	fma.s1 f8 = f6, f8, f8		// q1 = e0*q0 + q0
  (p6)	fma.s1 f6 = f6, f6, f7		// e1 = e0*e0 + 2^-34
  	;;
  #ifdef MODULO
  	setf.sig f7 = in0
  #endif
  (p6)	fma.s1 f6 = f6, f8, f8		// q2 = e1*q1 + q1
  	;;
  	FP_TO_INT(f6, f6)		// q = trunc(q2)
  	;;
  #ifdef MODULO
  	xma.l f6 = f6, f9, f7		// r = q*(-b) + a
  	;;
  #endif
  	getf.sig r8 = f6		// transfer result to result register
  	br.ret.sptk.many rp
  END(NAME)