#
 ! C68 4 byte floating point => 32 bit integer conversion routines
 !-----------------------------------------------------------------------------
 ! ported to 68000 by Kai-Uwe Bloem, 12/89
 !	#1	original author: Peter S. Housel 6/12/89,6/14/89
 !	#2	replaced shifts by swap if possible for speed increase	-kub-, 01/90
 !	#3	Added wrapper routine to provide C68 IEEE compatibility
 !												Dave & Keith Walker 	02/92
 !	#4	Changed entry/exit code for C68 v4.3 compatibility
 !		Removed ACK entry points										09/93
 !	#5	Changed to new parameter format 						-djw-	01/96
 !-----------------------------------------------------------------------------

	   .sect .text

	   .define .Ysftol

	.extern __huge_val
	.extern .overflow

BIAS4  =	   0x7F - 1

!----------------------------------------
!	   sp	   Return address
!	   sp+4    float to convert
!----------------------------------------
.Ysftol:
	   move.w  4(sp),d0 	   ! extract exp
	   move.w  d0,d2		   ! extract sign
	   lsr.w   #7,d0		   ! shift down 7
	   and.w   #0x0ff,d0	   ! kill sign bit

	   cmp.w   #BIAS4,d0	   ! check exponent
	   blt	   zer4 		   ! strictly fractional, no integer part ?
	   cmp.w   #BIAS4+32,d0    ! is it too big to fit in a 32-bit integer ?
	   bgt	   toobig

	   move.l  4(sp),d1
	   and.l   #0x7fffff,d1    ! remove exponent from mantissa
	   or.l    #0x800000,d1    ! restore implied leading "1"

	   sub.w   #BIAS4+24,d0    ! adjust exponent
	   bgt	   2f			   ! shift up
	   beq	   3f			   ! no shift

	   cmp.w   #-8,d0		   ! replace far shifts by swap
	   bgt	   1f
	   clr.w   d1			   ! shift fast, 16 bits
	   swap    d1
	   add.w   #16,d0		   ! account for swap
	   bgt	   2f
	   beq	   3f

1:	   lsr.l   #1,d1		   ! shift down to align radix point;
	   add.w   #1,d0		   ! extra bits fall off the end (no rounding)
	   blt	   1b			   ! shifted all the way down yet ?
	   bra	   3f

2:	   add.l   d1,d1		   ! shift up to align radix point
	   sub.w   #1,d0
	   bgt	   2b
	   bra	   3f
zer4:
	   clr.l   d1			   ! make the whole thing zero

3:	   move.l  d1,d0		   ! put integer into register
	   cmp.l   #0x80000000,d0  ! -2147483648 is a nasty evil special case
	   bne	   6f
	   tst.w   d2			   ! this had better be -2^31 and not 2^31
	   bpl	   toobig
	   bra	   8f
6:	   tst.l   d0			   ! sign bit set ? (i.e. too big)
	   bmi	   toobig
	   tst.w   d2			   ! is it negative ?
	   bpl	   8f
	   neg.l   d0			   ! negate

8:	move.l	(sp)+,a0			! get return address
	add.l	#4,sp				! tidy stack ( 1 x float)
	jmp 	(a0)				! return to caller

toobig:
	jsr .overflow	! Default overflow handling routine
	jsr .setmaxmin	! If control returned, set LONG_MAX/LONG_MIN
	bra 8b		! .., and exit backa to user