* MOTOROLA MICROPROCESSOR & MEMORY TECHNOLOGY GROUP
* M68000 Hi-Performance Microprocessor Division
* M68040 Software Package
*
* M68040 Software Package Copyright (c) 1993, 1994 Motorola Inc.
* All rights reserved.
*
* THE SOFTWARE is provided on an "AS IS" basis and without warranty.
* To the maximum extent permitted by applicable law,
* MOTOROLA DISCLAIMS ALL WARRANTIES WHETHER EXPRESS OR IMPLIED,
* INCLUDING IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A
* PARTICULAR PURPOSE and any warranty against infringement with
* regard to the SOFTWARE (INCLUDING ANY MODIFIED VERSIONS THEREOF)
* and any accompanying written materials.
*
* To the maximum extent permitted by applicable law,
* IN NO EVENT SHALL MOTOROLA BE LIABLE FOR ANY DAMAGES WHATSOEVER
* (INCLUDING WITHOUT LIMITATION, DAMAGES FOR LOSS OF BUSINESS
* PROFITS, BUSINESS INTERRUPTION, LOSS OF BUSINESS INFORMATION, OR
* OTHER PECUNIARY LOSS) ARISING OF THE USE OR INABILITY TO USE THE
* SOFTWARE. Motorola assumes no responsibility for the maintenance
* and support of the SOFTWARE.
*
* You are hereby granted a copyright license to use, modify, and
* distribute the SOFTWARE so long as this entire notice is retained
* without alteration in any modified and/or redistributed versions,
* and that such modified versions are clearly identified as such.
* No licenses are granted by implication, estoppel or otherwise
* under any patents or trademarks of Motorola, Inc.
*
* l_support.sa 1.2 5/1/91
*
L_SUPPORT IDNT 2,1 Motorola 040 Floating Point Software Package
*
* tag --- determine the type of an extended precision operand
*
* The tag values returned match the way the 68040 would have
* tagged them.
*
* Input: a0 points to operand
*
* Output d0.b = $00 norm
* $20 zero
* $40 inf
* $60 nan
* $80 denorm
* All other registers are unchanged
*
xdef tag
tag:
move.w LOCAL_EX(a0),d0
andi.w #$7fff,d0
beq.b chk_zro
cmpi.w #$7fff,d0
beq.b chk_inf
tag_nrm:
clr.b d0
rts
tag_nan:
move.b #$60,d0
rts
tag_dnrm:
move.b #$80,d0
rts
chk_zro:
btst.b #7,LOCAL_HI(a0) # check if J-bit is set
bne.b tag_nrm
tst.l LOCAL_HI(a0)
bne.b tag_dnrm
tst.l LOCAL_LO(a0)
bne.b tag_dnrm
tag_zero:
move.b #$20,d0
rts
chk_inf:
tst.l LOCAL_HI(a0)
bne.b tag_nan
tst.l LOCAL_LO(a0)
bne.b tag_nan
tag_inf:
move.b #$40,d0
rts
*
* t_dz, t_dz2 --- divide by zero exception
*
* t_dz2 is used by monadic functions such as flogn (from do_func).
* t_dz is used by monadic functions such as satanh (from the
* transcendental function).
*
xdef t_dz2
t_dz2:
fmovem.x mns_one,fp0
fmove.l d1,fpcr
fdiv.x pls_zero,fp0
rts
unf_pos:
fmovem.x pls_tiny,fp0
fmove.l d1,fpcr
fmul.x fp0,fp0
rts
*
* t_ovfl --- OVFL exception
*
* t_ovfl is called as an exit for monadic functions. t_ovfl2
* is for dyadic exits.
*
xdef t_ovfl
t_ovfl:
xdef t_ovfl2
move.l d1,USER_FPCR(a6) user's control register
move.l #ovfinx_mask,d0
bra.b t_work
t_ovfl2:
move.l #ovfl_inx_mask,d0
t_work:
btst.b #sign_bit,ETEMP(a6)
beq.b ovf_pos
ovf_neg:
fmovem.x mns_huge,fp0
fmove.l USER_FPCR(a6),fpcr
fmul.x pls_huge,fp0
fmove.l fpsr,d1
or.l d1,d0
fmove.l d0,fpsr
rts
ovf_pos:
fmovem.x pls_huge,fp0
fmove.l USER_FPCR(a6),fpcr
fmul.x pls_huge,fp0
fmove.l fpsr,d1
or.l d1,d0
fmove.l d0,fpsr
rts
*
* t_inx2 --- INEX2 exception (correct fpcr is in USER_FPCR(a6))
*
xdef t_inx2
t_inx2:
fmove.l fpsr,USER_FPSR(a6) capture incoming fpsr
fmove.l USER_FPCR(a6),fpcr
*
* create an inex2 exception by adding two numbers with very different exponents
* do the add in fp1 so as to not disturb the result sitting in fp0
*
fmove.x pls_one,fp1
fadd.x small,fp1
*
or.l #inx2a_mask,USER_FPSR(a6) ;set INEX2, AINEX
fmove.l USER_FPSR(a6),fpsr
rts
*
* t_frcinx --- Force Inex2 (for monadic functions)
*
xdef t_frcinx
t_frcinx:
fmove.l fpsr,USER_FPSR(a6) capture incoming fpsr
fmove.l d1,fpcr
*
* create an inex2 exception by adding two numbers with very different exponents
* do the add in fp1 so as to not disturb the result sitting in fp0
*
fmove.x pls_one,fp1
fadd.x small,fp1
*
or.l #inx2a_mask,USER_FPSR(a6) ;set INEX2, AINEX
btst.b #unfl_bit,FPSR_EXCEPT(a6) ;test for unfl bit set
beq.b no_uacc1 ;if clear, do not set aunfl
bset.b #aunfl_bit,FPSR_AEXCEPT(a6)
no_uacc1:
fmove.l USER_FPSR(a6),fpsr
rts
*
* dst_nan --- force result when destination is a NaN
*
xdef dst_nan
dst_nan:
fmove.l USER_FPCR(a6),fpcr
fmove.x FPTEMP(a6),fp0
rts
*
* src_nan --- force result when source is a NaN
*
xdef src_nan
src_nan:
fmove.l USER_FPCR(a6),fpcr
fmove.x ETEMP(a6),fp0
rts
*
* mon_nan --- force result when source is a NaN (monadic version)
*
* This is the same as src_nan except that the user's fpcr comes
* in via d1, not USER_FPCR(a6).
*
xdef mon_nan
mon_nan:
fmove.l d1,fpcr
fmove.x ETEMP(a6),fp0
rts
*
* t_extdnrm, t_resdnrm --- generate results for denorm inputs
*
* For all functions that have a denormalized input and that f(x)=x,
* this is the entry point.
*
xdef t_extdnrm
t_extdnrm:
fmove.l d1,fpcr
fmove.x LOCAL_EX(a0),fp0
fmove.l fpsr,d0
or.l #unfinx_mask,d0
fmove.l d0,fpsr
rts
xdef sto_cos
sto_cos:
fmovem.x LOCAL_EX(a0),fp1
rts
*
* Native instruction support
*
* Some systems may need entry points even for 68040 native
* instructions. These routines are provided for
* convenience.
*
xdef sadd
sadd:
fmovem.x FPTEMP(a6),fp0
fmove.l USER_FPCR(a6),fpcr
fadd.x ETEMP(a6),fp0
rts
*
* l_sint,l_sintrz,l_sintd --- special wrapper for fint and fintrz
*
* On entry, move the user's FPCR to USER_FPCR.
*
* On return from, we need to pickup the INEX2/AINEX bits
* that are in USER_FPSR.
*
xref sint
xref sintrz
xref sintd
