do_func.S
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- |
- | 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
- |
- | THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF MOTOROLA
- | The copyright notice above does not evidence any
- | actual or intended publication of such source code.
- 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