|
| do_func.sa 3.4 2/18/91
|
| Do_func performs the unimplemented operation. The operation
| to be performed is determined from the lower 7 bits of the
| extension word (except in the case of fmovecr and fsincos).
| The opcode and tag bits form an index into a jump table in
| tbldo.sa. Cases of zero, infinity and NaN are handled in
| do_func by forcing the default result. Normalized and
| denormalized (there are no unnormalized numbers at this
| point) are passed onto the emulation code.
|
| CMDREG1B and STAG are extracted from the fsave frame
| and combined to form the table index. The function called
| will start with a0 pointing to the ETEMP operand. Dyadic
| functions can find FPTEMP at -12(a0).
|
| Called functions return their result in fp0. Sincos returns
| sin(x) in fp0 and cos(x) in fp1.
|
| Copyright (C) Motorola, Inc. 1990
| All Rights Reserved
|
| For details on the license for this file, please see the
| file, README, in this same directory.
DO_FUNC: |idnt 2,1 | Motorola 040 Floating Point Software Package
|section 8
#include "fpsp.h"
|xref t_dz2
|xref t_operr
|xref t_inx2
|xref t_resdnrm
|xref dst_nan
|xref src_nan
|xref nrm_set
|xref sto_cos
|xref tblpre
|xref slognp1,slogn,slog10,slog2
|xref slognd,slog10d,slog2d
|xref smod,srem
|xref sscale
|xref smovcr
PONE: .long 0x3fff0000,0x80000000,0x00000000 |+1
MONE: .long 0xbfff0000,0x80000000,0x00000000 |-1
PZERO: .long 0x00000000,0x00000000,0x00000000 |+0
MZERO: .long 0x80000000,0x00000000,0x00000000 |-0
PINF: .long 0x7fff0000,0x00000000,0x00000000 |+inf
MINF: .long 0xffff0000,0x00000000,0x00000000 |-inf
QNAN: .long 0x7fff0000,0xffffffff,0xffffffff |non-signaling nan
PPIBY2: .long 0x3FFF0000,0xC90FDAA2,0x2168C235 |+PI/2
MPIBY2: .long 0xbFFF0000,0xC90FDAA2,0x2168C235 |-PI/2
.global do_func
do_func:
clrb CU_ONLY(%a6)
|
| Check for fmovecr. It does not follow the format of fp gen
| unimplemented instructions. The test is on the upper 6 bits;
| if they are $17, the inst is fmovecr. Call entry smovcr
| directly.
|
bfextu CMDREG1B(%a6){#0:#6},%d0 |get opclass and src fields
cmpil #0x17,%d0 |if op class and size fields are $17,
| ;it is FMOVECR; if not, continue
bnes not_fmovecr
jmp smovcr |fmovecr; jmp directly to emulation
not_fmovecr:
movew CMDREG1B(%a6),%d0
andl #0x7F,%d0
cmpil #0x38,%d0 |if the extension is >= $38,
bge serror |it is illegal
bfextu STAG(%a6){#0:#3},%d1
lsll #3,%d0 |make room for STAG
addl %d1,%d0 |combine for final index into table
leal tblpre,%a1 |start of monster jump table
movel (%a1,%d0.w*4),%a1 |real target address
leal ETEMP(%a6),%a0 |a0 is pointer to src op
movel USER_FPCR(%a6),%d1
andl #0xFF,%d1 | discard all but rounding mode/prec
fmovel #0,%fpcr
jmp (%a1)
|
| ERROR
|
.global serror
serror:
st STORE_FLG(%a6)
rts
|
| These routines load forced values into fp0. They are called
| by index into tbldo.
|
| Load a signed zero to fp0 and set inex2/ainex
|
.global snzrinx
snzrinx:
btstb #sign_bit,LOCAL_EX(%a0) |get sign of source operand
bnes ld_mzinx |if negative, branch
bsr ld_pzero |bsr so we can return and set inx
bra t_inx2 |now, set the inx for the next inst
ld_mzinx:
bsr ld_mzero |if neg, load neg zero, return here
bra t_inx2 |now, set the inx for the next inst
|
| Load a signed zero to fp0; do not set inex2/ainex
|
.global szero
szero:
btstb #sign_bit,LOCAL_EX(%a0) |get sign of source operand
bne ld_mzero |if neg, load neg zero
bra ld_pzero |load positive zero
|
| Load a signed infinity to fp0; do not set inex2/ainex
|
.global sinf
sinf:
btstb #sign_bit,LOCAL_EX(%a0) |get sign of source operand
bne ld_minf |if negative branch
bra ld_pinf
|
| Load a signed one to fp0; do not set inex2/ainex
|
.global sone
sone:
btstb #sign_bit,LOCAL_EX(%a0) |check sign of source
bne ld_mone
bra ld_pone
|
| Load a signed pi/2 to fp0; do not set inex2/ainex
|
.global spi_2
spi_2:
btstb #sign_bit,LOCAL_EX(%a0) |check sign of source
bne ld_mpi2
bra ld_ppi2
|
| Load either a +0 or +inf for plus/minus operand
|
.global szr_inf
szr_inf:
btstb #sign_bit,LOCAL_EX(%a0) |check sign of source
bne ld_pzero
bra ld_pinf
|
| Result is either an operr or +inf for plus/minus operand
| [Used by slogn, slognp1, slog10, and slog2]
|
.global sopr_inf
sopr_inf:
btstb #sign_bit,LOCAL_EX(%a0) |check sign of source
bne t_operr
bra ld_pinf
|
| FLOGNP1
|
.global sslognp1
sslognp1:
fmovemx (%a0),%fp0-%fp0
fcmpb #-1,%fp0
fbgt slognp1
fbeq t_dz2 |if = -1, divide by zero exception
fmovel #0,%FPSR |clr N flag
bra t_operr |take care of operands < -1
|
| FETOXM1
|
.global setoxm1i
setoxm1i:
btstb #sign_bit,LOCAL_EX(%a0) |check sign of source
bne ld_mone
bra ld_pinf
|
| FLOGN
|
| Test for 1.0 as an input argument, returning +zero. Also check
| the sign and return operr if negative.
|
.global sslogn
sslogn:
btstb #sign_bit,LOCAL_EX(%a0)
bne t_operr |take care of operands < 0
cmpiw #0x3fff,LOCAL_EX(%a0) |test for 1.0 input
bne slogn
cmpil #0x80000000,LOCAL_HI(%a0)
bne slogn
tstl LOCAL_LO(%a0)
bne slogn
fmovex PZERO,%fp0
rts
.global sslognd
sslognd:
btstb #sign_bit,LOCAL_EX(%a0)
beq slognd
bra t_operr |take care of operands < 0
|
| FLOG10
|
.global sslog10
sslog10:
btstb #sign_bit,LOCAL_EX(%a0)
bne t_operr |take care of operands < 0
cmpiw #0x3fff,LOCAL_EX(%a0) |test for 1.0 input
bne slog10
cmpil #0x80000000,LOCAL_HI(%a0)
bne slog10
tstl LOCAL_LO(%a0)
bne slog10
fmovex PZERO,%fp0
rts
.global sslog10d
sslog10d:
btstb #sign_bit,LOCAL_EX(%a0)
beq slog10d
bra t_operr |take care of operands < 0
|
| FLOG2
|
.global sslog2
sslog2:
btstb #sign_bit,LOCAL_EX(%a0)
bne t_operr |take care of operands < 0
cmpiw #0x3fff,LOCAL_EX(%a0) |test for 1.0 input
bne slog2
cmpil #0x80000000,LOCAL_HI(%a0)
bne slog2
tstl LOCAL_LO(%a0)
bne slog2
fmovex PZERO,%fp0
rts
.global sslog2d
sslog2d:
btstb #sign_bit,LOCAL_EX(%a0)
beq slog2d
bra t_operr |take care of operands < 0
|
| FMOD
|
pmodt:
| ;$21 fmod
| ;dtag,stag
.long smod | 00,00 norm,norm = normal
.long smod_oper | 00,01 norm,zero = nan with operr
.long smod_fpn | 00,10 norm,inf = fpn
.long smod_snan | 00,11 norm,nan = nan
.long smod_zro | 01,00 zero,norm = +-zero
.long smod_oper | 01,01 zero,zero = nan with operr
.long smod_zro | 01,10 zero,inf = +-zero
.long smod_snan | 01,11 zero,nan = nan
.long smod_oper | 10,00 inf,norm = nan with operr
.long smod_oper | 10,01 inf,zero = nan with operr
.long smod_oper | 10,10 inf,inf = nan with operr
.long smod_snan | 10,11 inf,nan = nan
.long smod_dnan | 11,00 nan,norm = nan
.long smod_dnan | 11,01 nan,zero = nan
.long smod_dnan | 11,10 nan,inf = nan
.long smod_dnan | 11,11 nan,nan = nan
.global pmod
pmod:
clrb FPSR_QBYTE(%a6) | clear quotient field
bfextu STAG(%a6){#0:#3},%d0 |stag = d0
bfextu DTAG(%a6){#0:#3},%d1 |dtag = d1
|
| Alias extended denorms to norms for the jump table.
|
bclrl #2,%d0
bclrl #2,%d1
lslb #2,%d1
orb %d0,%d1 |d1{3:2} = dtag, d1{1:0} = stag
| ;Tag values:
| ;00 = norm or denorm
| ;01 = zero
| ;10 = inf
| ;11 = nan
lea pmodt,%a1
movel (%a1,%d1.w*4),%a1
jmp (%a1)
smod_snan:
bra src_nan
smod_dnan:
bra dst_nan
smod_oper:
bra t_operr
smod_zro:
moveb ETEMP(%a6),%d1 |get sign of src op
moveb FPTEMP(%a6),%d0 |get sign of dst op
eorb %d0,%d1 |get exor of sign bits
btstl #7,%d1 |test for sign
beqs smod_zsn |if clr, do not set sign big
bsetb #q_sn_bit,FPSR_QBYTE(%a6) |set q-byte sign bit
smod_zsn:
btstl #7,%d0 |test if + or -
beq ld_pzero |if pos then load +0
bra ld_mzero |else neg load -0
smod_fpn:
moveb ETEMP(%a6),%d1 |get sign of src op
moveb FPTEMP(%a6),%d0 |get sign of dst op
eorb %d0,%d1 |get exor of sign bits
btstl #7,%d1 |test for sign
beqs smod_fsn |if clr, do not set sign big
bsetb #q_sn_bit,FPSR_QBYTE(%a6) |set q-byte sign bit
smod_fsn:
tstb DTAG(%a6) |filter out denormal destination case
bpls smod_nrm |
leal FPTEMP(%a6),%a0 |a0<- addr(FPTEMP)
bra t_resdnrm |force UNFL(but exact) result
smod_nrm:
fmovel USER_FPCR(%a6),%fpcr |use user's rmode and precision
fmovex FPTEMP(%a6),%fp0 |return dest to fp0
rts
|
| FREM
|
premt:
| ;$25 frem
| ;dtag,stag
.long srem | 00,00 norm,norm = normal
.long srem_oper | 00,01 norm,zero = nan with operr
.long srem_fpn | 00,10 norm,inf = fpn
.long srem_snan | 00,11 norm,nan = nan
.long srem_zro | 01,00 zero,norm = +-zero
.long srem_oper | 01,01 zero,zero = nan with operr
.long srem_zro | 01,10 zero,inf = +-zero
.long srem_snan | 01,11 zero,nan = nan
.long srem_oper | 10,00 inf,norm = nan with operr
.long srem_oper | 10,01 inf,zero = nan with operr
.long srem_oper | 10,10 inf,inf = nan with operr
.long srem_snan | 10,11 inf,nan = nan
.long srem_dnan | 11,00 nan,norm = nan
.long srem_dnan | 11,01 nan,zero = nan
.long srem_dnan | 11,10 nan,inf = nan
.long srem_dnan | 11,11 nan,nan = nan
.global prem
prem:
clrb FPSR_QBYTE(%a6) |clear quotient field
bfextu STAG(%a6){#0:#3},%d0 |stag = d0
bfextu DTAG(%a6){#0:#3},%d1 |dtag = d1
|
| Alias extended denorms to norms for the jump table.
|
bclr #2,%d0
bclr #2,%d1
lslb #2,%d1
orb %d0,%d1 |d1{3:2} = dtag, d1{1:0} = stag
| ;Tag values:
| ;00 = norm or denorm
| ;01 = zero
| ;10 = inf
| ;11 = nan
lea premt,%a1
movel (%a1,%d1.w*4),%a1
jmp (%a1)
srem_snan:
bra src_nan
srem_dnan:
bra dst_nan
srem_oper:
bra t_operr
srem_zro:
moveb ETEMP(%a6),%d1 |get sign of src op
moveb FPTEMP(%a6),%d0 |get sign of dst op
eorb %d0,%d1 |get exor of sign bits
btstl #7,%d1 |test for sign
beqs srem_zsn |if clr, do not set sign big
bsetb #q_sn_bit,FPSR_QBYTE(%a6) |set q-byte sign bit
srem_zsn:
btstl #7,%d0 |test if + or -
beq ld_pzero |if pos then load +0
bra ld_mzero |else neg load -0
srem_fpn:
moveb ETEMP(%a6),%d1 |get sign of src op
moveb FPTEMP(%a6),%d0 |get sign of dst op
eorb %d0,%d1 |get exor of sign bits
btstl #7,%d1 |test for sign
beqs srem_fsn |if clr, do not set sign big
bsetb #q_sn_bit,FPSR_QBYTE(%a6) |set q-byte sign bit
srem_fsn:
tstb DTAG(%a6) |filter out denormal destination case
bpls srem_nrm |
leal FPTEMP(%a6),%a0 |a0<- addr(FPTEMP)
bra t_resdnrm |force UNFL(but exact) result
srem_nrm:
fmovel USER_FPCR(%a6),%fpcr |use user's rmode and precision
fmovex FPTEMP(%a6),%fp0 |return dest to fp0
rts
|
| FSCALE
|
pscalet:
| ;$26 fscale
| ;dtag,stag
.long sscale | 00,00 norm,norm = result
.long sscale | 00,01 norm,zero = fpn
.long scl_opr | 00,10 norm,inf = nan with operr
.long scl_snan | 00,11 norm,nan = nan
.long scl_zro | 01,00 zero,norm = +-zero
.long scl_zro | 01,01 zero,zero = +-zero
.long scl_opr | 01,10 zero,inf = nan with operr
.long scl_snan | 01,11 zero,nan = nan
.long scl_inf | 10,00 inf,norm = +-inf
.long scl_inf | 10,01 inf,zero = +-inf
.long scl_opr | 10,10 inf,inf = nan with operr
.long scl_snan | 10,11 inf,nan = nan
.long scl_dnan | 11,00 nan,norm = nan
.long scl_dnan | 11,01 nan,zero = nan
.long scl_dnan | 11,10 nan,inf = nan
.long scl_dnan | 11,11 nan,nan = nan
.global pscale
pscale:
bfextu STAG(%a6){#0:#3},%d0 |stag in d0
bfextu DTAG(%a6){#0:#3},%d1 |dtag in d1
bclrl #2,%d0 |alias denorm into norm
bclrl #2,%d1 |alias denorm into norm
lslb #2,%d1
orb %d0,%d1 |d1{4:2} = dtag, d1{1:0} = stag
| ;dtag values stag values:
| ;000 = norm 00 = norm
| ;001 = zero 01 = zero
| ;010 = inf 10 = inf
| ;011 = nan 11 = nan
| ;100 = dnrm
|
|
leal pscalet,%a1 |load start of jump table
movel (%a1,%d1.w*4),%a1 |load a1 with label depending on tag
jmp (%a1) |go to the routine
scl_opr:
bra t_operr
scl_dnan:
bra dst_nan
scl_zro:
btstb #sign_bit,FPTEMP_EX(%a6) |test if + or -
beq ld_pzero |if pos then load +0
bra ld_mzero |if neg then load -0
scl_inf:
btstb #sign_bit,FPTEMP_EX(%a6) |test if + or -
beq ld_pinf |if pos then load +inf
bra ld_minf |else neg load -inf
scl_snan:
bra src_nan
|
| FSINCOS
|
.global ssincosz
ssincosz:
btstb #sign_bit,ETEMP(%a6) |get sign
beqs sincosp
fmovex MZERO,%fp0
bras sincoscom
sincosp:
fmovex PZERO,%fp0
sincoscom:
fmovemx PONE,%fp1-%fp1 |do not allow FPSR to be affected
bra sto_cos |store cosine result
.global ssincosi
ssincosi:
fmovex QNAN,%fp1 |load NAN
bsr sto_cos |store cosine result
fmovex QNAN,%fp0 |load NAN
bra t_operr
.global ssincosnan
ssincosnan:
movel ETEMP_EX(%a6),FP_SCR1(%a6)
movel ETEMP_HI(%a6),FP_SCR1+4(%a6)
movel ETEMP_LO(%a6),FP_SCR1+8(%a6)
bsetb #signan_bit,FP_SCR1+4(%a6)
fmovemx FP_SCR1(%a6),%fp1-%fp1
bsr sto_cos
bra src_nan
|
| This code forces default values for the zero, inf, and nan cases
| in the transcendentals code. The CC bits must be set in the
| stacked FPSR to be correctly reported.
|
|**Returns +PI/2
.global ld_ppi2
ld_ppi2:
fmovex PPIBY2,%fp0 |load +pi/2
bra t_inx2 |set inex2 exc
|**Returns -PI/2
.global ld_mpi2
ld_mpi2:
fmovex MPIBY2,%fp0 |load -pi/2
orl #neg_mask,USER_FPSR(%a6) |set N bit
bra t_inx2 |set inex2 exc
|**Returns +inf
.global ld_pinf
ld_pinf:
fmovex PINF,%fp0 |load +inf
orl #inf_mask,USER_FPSR(%a6) |set I bit
rts
|**Returns -inf
.global ld_minf
ld_minf:
fmovex MINF,%fp0 |load -inf
orl #neg_mask+inf_mask,USER_FPSR(%a6) |set N and I bits
rts
|**Returns +1
.global ld_pone
ld_pone:
fmovex PONE,%fp0 |load +1
rts
|**Returns -1
.global ld_mone
ld_mone:
fmovex MONE,%fp0 |load -1
orl #neg_mask,USER_FPSR(%a6) |set N bit
rts
|**Returns +0
.global ld_pzero
ld_pzero:
fmovex PZERO,%fp0 |load +0
orl #z_mask,USER_FPSR(%a6) |set Z bit
rts
|**Returns -0
.global ld_mzero
ld_mzero:
fmovex MZERO,%fp0 |load -0
orl #neg_mask+z_mask,USER_FPSR(%a6) |set N and Z bits
rts
|end