| 1 |
3 |
xianfeng |
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
| 2 |
|
|
MOTOROLA MICROPROCESSOR & MEMORY TECHNOLOGY GROUP
|
| 3 |
|
|
M68000 Hi-Performance Microprocessor Division
|
| 4 |
|
|
M68060 Software Package
|
| 5 |
|
|
Production Release P1.00 -- October 10, 1994
|
| 6 |
|
|
|
| 7 |
|
|
M68060 Software Package Copyright © 1993, 1994 Motorola Inc. All rights reserved.
|
| 8 |
|
|
|
| 9 |
|
|
THE SOFTWARE is provided on an "AS IS" basis and without warranty.
|
| 10 |
|
|
To the maximum extent permitted by applicable law,
|
| 11 |
|
|
MOTOROLA DISCLAIMS ALL WARRANTIES WHETHER EXPRESS OR IMPLIED,
|
| 12 |
|
|
INCLUDING IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
|
| 13 |
|
|
and any warranty against infringement with regard to the SOFTWARE
|
| 14 |
|
|
(INCLUDING ANY MODIFIED VERSIONS THEREOF) and any accompanying written materials.
|
| 15 |
|
|
|
| 16 |
|
|
To the maximum extent permitted by applicable law,
|
| 17 |
|
|
IN NO EVENT SHALL MOTOROLA BE LIABLE FOR ANY DAMAGES WHATSOEVER
|
| 18 |
|
|
(INCLUDING WITHOUT LIMITATION, DAMAGES FOR LOSS OF BUSINESS PROFITS,
|
| 19 |
|
|
BUSINESS INTERRUPTION, LOSS OF BUSINESS INFORMATION, OR OTHER PECUNIARY LOSS)
|
| 20 |
|
|
ARISING OF THE USE OR INABILITY TO USE THE SOFTWARE.
|
| 21 |
|
|
Motorola assumes no responsibility for the maintenance and support of the SOFTWARE.
|
| 22 |
|
|
|
| 23 |
|
|
You are hereby granted a copyright license to use, modify, and distribute the SOFTWARE
|
| 24 |
|
|
so long as this entire notice is retained without alteration in any modified and/or
|
| 25 |
|
|
redistributed versions, and that such modified versions are clearly identified as such.
|
| 26 |
|
|
No licenses are granted by implication, estoppel or otherwise under any patents
|
| 27 |
|
|
or trademarks of Motorola, Inc.
|
| 28 |
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
| 29 |
|
|
# litop.s:
|
| 30 |
|
|
# This file is appended to the top of the 060FPLSP package
|
| 31 |
|
|
# and contains the entry points into the package. The user, in
|
| 32 |
|
|
# effect, branches to one of the branch table entries located here.
|
| 33 |
|
|
#
|
| 34 |
|
|
|
| 35 |
|
|
bra.l _060LSP__idivs64_
|
| 36 |
|
|
short 0x0000
|
| 37 |
|
|
bra.l _060LSP__idivu64_
|
| 38 |
|
|
short 0x0000
|
| 39 |
|
|
|
| 40 |
|
|
bra.l _060LSP__imuls64_
|
| 41 |
|
|
short 0x0000
|
| 42 |
|
|
bra.l _060LSP__imulu64_
|
| 43 |
|
|
short 0x0000
|
| 44 |
|
|
|
| 45 |
|
|
bra.l _060LSP__cmp2_Ab_
|
| 46 |
|
|
short 0x0000
|
| 47 |
|
|
bra.l _060LSP__cmp2_Aw_
|
| 48 |
|
|
short 0x0000
|
| 49 |
|
|
bra.l _060LSP__cmp2_Al_
|
| 50 |
|
|
short 0x0000
|
| 51 |
|
|
bra.l _060LSP__cmp2_Db_
|
| 52 |
|
|
short 0x0000
|
| 53 |
|
|
bra.l _060LSP__cmp2_Dw_
|
| 54 |
|
|
short 0x0000
|
| 55 |
|
|
bra.l _060LSP__cmp2_Dl_
|
| 56 |
|
|
short 0x0000
|
| 57 |
|
|
|
| 58 |
|
|
# leave room for future possible aditions.
|
| 59 |
|
|
align 0x200
|
| 60 |
|
|
|
| 61 |
|
|
#########################################################################
|
| 62 |
|
|
# XDEF **************************************************************** #
|
| 63 |
|
|
# _060LSP__idivu64_(): Emulate 64-bit unsigned div instruction. #
|
| 64 |
|
|
# _060LSP__idivs64_(): Emulate 64-bit signed div instruction. #
|
| 65 |
|
|
# #
|
| 66 |
|
|
# This is the library version which is accessed as a subroutine #
|
| 67 |
|
|
# and therefore does not work exactly like the 680X0 div{s,u}.l #
|
| 68 |
|
|
# 64-bit divide instruction. #
|
| 69 |
|
|
# #
|
| 70 |
|
|
# XREF **************************************************************** #
|
| 71 |
|
|
# None. #
|
| 72 |
|
|
# #
|
| 73 |
|
|
# INPUT *************************************************************** #
|
| 74 |
|
|
# 0x4(sp) = divisor #
|
| 75 |
|
|
# 0x8(sp) = hi(dividend) #
|
| 76 |
|
|
# 0xc(sp) = lo(dividend) #
|
| 77 |
|
|
# 0x10(sp) = pointer to location to place quotient/remainder #
|
| 78 |
|
|
# #
|
| 79 |
|
|
# OUTPUT ************************************************************** #
|
| 80 |
|
|
# 0x10(sp) = points to location of remainder/quotient. #
|
| 81 |
|
|
# remainder is in first longword, quotient is in 2nd. #
|
| 82 |
|
|
# #
|
| 83 |
|
|
# ALGORITHM *********************************************************** #
|
| 84 |
|
|
# If the operands are signed, make them unsigned and save the #
|
| 85 |
|
|
# sign info for later. Separate out special cases like divide-by-zero #
|
| 86 |
|
|
# or 32-bit divides if possible. Else, use a special math algorithm #
|
| 87 |
|
|
# to calculate the result. #
|
| 88 |
|
|
# Restore sign info if signed instruction. Set the condition #
|
| 89 |
|
|
# codes before performing the final "rts". If the divisor was equal to #
|
| 90 |
|
|
# zero, then perform a divide-by-zero using a 16-bit implemented #
|
| 91 |
|
|
# divide instruction. This way, the operating system can record that #
|
| 92 |
|
|
# the event occurred even though it may not point to the correct place. #
|
| 93 |
|
|
# #
|
| 94 |
|
|
#########################################################################
|
| 95 |
|
|
|
| 96 |
|
|
set POSNEG, -1
|
| 97 |
|
|
set NDIVISOR, -2
|
| 98 |
|
|
set NDIVIDEND, -3
|
| 99 |
|
|
set DDSECOND, -4
|
| 100 |
|
|
set DDNORMAL, -8
|
| 101 |
|
|
set DDQUOTIENT, -12
|
| 102 |
|
|
set DIV64_CC, -16
|
| 103 |
|
|
|
| 104 |
|
|
##########
|
| 105 |
|
|
# divs.l #
|
| 106 |
|
|
##########
|
| 107 |
|
|
global _060LSP__idivs64_
|
| 108 |
|
|
_060LSP__idivs64_:
|
| 109 |
|
|
# PROLOGUE BEGIN ########################################################
|
| 110 |
|
|
link.w %a6,&-16
|
| 111 |
|
|
movm.l &0x3f00,-(%sp) # save d2-d7
|
| 112 |
|
|
# fmovm.l &0x0,-(%sp) # save no fpregs
|
| 113 |
|
|
# PROLOGUE END ##########################################################
|
| 114 |
|
|
|
| 115 |
|
|
mov.w %cc,DIV64_CC(%a6)
|
| 116 |
|
|
st POSNEG(%a6) # signed operation
|
| 117 |
|
|
bra.b ldiv64_cont
|
| 118 |
|
|
|
| 119 |
|
|
##########
|
| 120 |
|
|
# divu.l #
|
| 121 |
|
|
##########
|
| 122 |
|
|
global _060LSP__idivu64_
|
| 123 |
|
|
_060LSP__idivu64_:
|
| 124 |
|
|
# PROLOGUE BEGIN ########################################################
|
| 125 |
|
|
link.w %a6,&-16
|
| 126 |
|
|
movm.l &0x3f00,-(%sp) # save d2-d7
|
| 127 |
|
|
# fmovm.l &0x0,-(%sp) # save no fpregs
|
| 128 |
|
|
# PROLOGUE END ##########################################################
|
| 129 |
|
|
|
| 130 |
|
|
mov.w %cc,DIV64_CC(%a6)
|
| 131 |
|
|
sf POSNEG(%a6) # unsigned operation
|
| 132 |
|
|
|
| 133 |
|
|
ldiv64_cont:
|
| 134 |
|
|
mov.l 0x8(%a6),%d7 # fetch divisor
|
| 135 |
|
|
|
| 136 |
|
|
beq.w ldiv64eq0 # divisor is = 0!!!
|
| 137 |
|
|
|
| 138 |
|
|
mov.l 0xc(%a6), %d5 # get dividend hi
|
| 139 |
|
|
mov.l 0x10(%a6), %d6 # get dividend lo
|
| 140 |
|
|
|
| 141 |
|
|
# separate signed and unsigned divide
|
| 142 |
|
|
tst.b POSNEG(%a6) # signed or unsigned?
|
| 143 |
|
|
beq.b ldspecialcases # use positive divide
|
| 144 |
|
|
|
| 145 |
|
|
# save the sign of the divisor
|
| 146 |
|
|
# make divisor unsigned if it's negative
|
| 147 |
|
|
tst.l %d7 # chk sign of divisor
|
| 148 |
|
|
slt NDIVISOR(%a6) # save sign of divisor
|
| 149 |
|
|
bpl.b ldsgndividend
|
| 150 |
|
|
neg.l %d7 # complement negative divisor
|
| 151 |
|
|
|
| 152 |
|
|
# save the sign of the dividend
|
| 153 |
|
|
# make dividend unsigned if it's negative
|
| 154 |
|
|
ldsgndividend:
|
| 155 |
|
|
tst.l %d5 # chk sign of hi(dividend)
|
| 156 |
|
|
slt NDIVIDEND(%a6) # save sign of dividend
|
| 157 |
|
|
bpl.b ldspecialcases
|
| 158 |
|
|
|
| 159 |
|
|
mov.w &0x0, %cc # clear 'X' cc bit
|
| 160 |
|
|
negx.l %d6 # complement signed dividend
|
| 161 |
|
|
negx.l %d5
|
| 162 |
|
|
|
| 163 |
|
|
# extract some special cases:
|
| 164 |
|
|
# - is (dividend == 0) ?
|
| 165 |
|
|
# - is (hi(dividend) == 0 && (divisor <= lo(dividend))) ? (32-bit div)
|
| 166 |
|
|
ldspecialcases:
|
| 167 |
|
|
tst.l %d5 # is (hi(dividend) == 0)
|
| 168 |
|
|
bne.b ldnormaldivide # no, so try it the long way
|
| 169 |
|
|
|
| 170 |
|
|
tst.l %d6 # is (lo(dividend) == 0), too
|
| 171 |
|
|
beq.w lddone # yes, so (dividend == 0)
|
| 172 |
|
|
|
| 173 |
|
|
cmp.l %d7,%d6 # is (divisor <= lo(dividend))
|
| 174 |
|
|
bls.b ld32bitdivide # yes, so use 32 bit divide
|
| 175 |
|
|
|
| 176 |
|
|
exg %d5,%d6 # q = 0, r = dividend
|
| 177 |
|
|
bra.w ldivfinish # can't divide, we're done.
|
| 178 |
|
|
|
| 179 |
|
|
ld32bitdivide:
|
| 180 |
|
|
tdivu.l %d7, %d5:%d6 # it's only a 32/32 bit div!
|
| 181 |
|
|
|
| 182 |
|
|
bra.b ldivfinish
|
| 183 |
|
|
|
| 184 |
|
|
ldnormaldivide:
|
| 185 |
|
|
# last special case:
|
| 186 |
|
|
# - is hi(dividend) >= divisor ? if yes, then overflow
|
| 187 |
|
|
cmp.l %d7,%d5
|
| 188 |
|
|
bls.b lddovf # answer won't fit in 32 bits
|
| 189 |
|
|
|
| 190 |
|
|
# perform the divide algorithm:
|
| 191 |
|
|
bsr.l ldclassical # do int divide
|
| 192 |
|
|
|
| 193 |
|
|
# separate into signed and unsigned finishes.
|
| 194 |
|
|
ldivfinish:
|
| 195 |
|
|
tst.b POSNEG(%a6) # do divs, divu separately
|
| 196 |
|
|
beq.b lddone # divu has no processing!!!
|
| 197 |
|
|
|
| 198 |
|
|
# it was a divs.l, so ccode setting is a little more complicated...
|
| 199 |
|
|
tst.b NDIVIDEND(%a6) # remainder has same sign
|
| 200 |
|
|
beq.b ldcc # as dividend.
|
| 201 |
|
|
neg.l %d5 # sgn(rem) = sgn(dividend)
|
| 202 |
|
|
ldcc:
|
| 203 |
|
|
mov.b NDIVISOR(%a6), %d0
|
| 204 |
|
|
eor.b %d0, NDIVIDEND(%a6) # chk if quotient is negative
|
| 205 |
|
|
beq.b ldqpos # branch to quot positive
|
| 206 |
|
|
|
| 207 |
|
|
# 0x80000000 is the largest number representable as a 32-bit negative
|
| 208 |
|
|
# number. the negative of 0x80000000 is 0x80000000.
|
| 209 |
|
|
cmpi.l %d6, &0x80000000 # will (-quot) fit in 32 bits?
|
| 210 |
|
|
bhi.b lddovf
|
| 211 |
|
|
|
| 212 |
|
|
neg.l %d6 # make (-quot) 2's comp
|
| 213 |
|
|
|
| 214 |
|
|
bra.b lddone
|
| 215 |
|
|
|
| 216 |
|
|
ldqpos:
|
| 217 |
|
|
btst &0x1f, %d6 # will (+quot) fit in 32 bits?
|
| 218 |
|
|
bne.b lddovf
|
| 219 |
|
|
|
| 220 |
|
|
lddone:
|
| 221 |
|
|
# if the register numbers are the same, only the quotient gets saved.
|
| 222 |
|
|
# so, if we always save the quotient second, we save ourselves a cmp&beq
|
| 223 |
|
|
andi.w &0x10,DIV64_CC(%a6)
|
| 224 |
|
|
mov.w DIV64_CC(%a6),%cc
|
| 225 |
|
|
tst.l %d6 # may set 'N' ccode bit
|
| 226 |
|
|
|
| 227 |
|
|
# here, the result is in d1 and d0. the current strategy is to save
|
| 228 |
|
|
# the values at the location pointed to by a0.
|
| 229 |
|
|
# use movm here to not disturb the condition codes.
|
| 230 |
|
|
ldexit:
|
| 231 |
|
|
movm.l &0x0060,([0x14,%a6]) # save result
|
| 232 |
|
|
|
| 233 |
|
|
# EPILOGUE BEGIN ########################################################
|
| 234 |
|
|
# fmovm.l (%sp)+,&0x0 # restore no fpregs
|
| 235 |
|
|
movm.l (%sp)+,&0x00fc # restore d2-d7
|
| 236 |
|
|
unlk %a6
|
| 237 |
|
|
# EPILOGUE END ##########################################################
|
| 238 |
|
|
|
| 239 |
|
|
rts
|
| 240 |
|
|
|
| 241 |
|
|
# the result should be the unchanged dividend
|
| 242 |
|
|
lddovf:
|
| 243 |
|
|
mov.l 0xc(%a6), %d5 # get dividend hi
|
| 244 |
|
|
mov.l 0x10(%a6), %d6 # get dividend lo
|
| 245 |
|
|
|
| 246 |
|
|
andi.w &0x1c,DIV64_CC(%a6)
|
| 247 |
|
|
ori.w &0x02,DIV64_CC(%a6) # set 'V' ccode bit
|
| 248 |
|
|
mov.w DIV64_CC(%a6),%cc
|
| 249 |
|
|
|
| 250 |
|
|
bra.b ldexit
|
| 251 |
|
|
|
| 252 |
|
|
ldiv64eq0:
|
| 253 |
|
|
mov.l 0xc(%a6),([0x14,%a6])
|
| 254 |
|
|
mov.l 0x10(%a6),([0x14,%a6],0x4)
|
| 255 |
|
|
|
| 256 |
|
|
mov.w DIV64_CC(%a6),%cc
|
| 257 |
|
|
|
| 258 |
|
|
# EPILOGUE BEGIN ########################################################
|
| 259 |
|
|
# fmovm.l (%sp)+,&0x0 # restore no fpregs
|
| 260 |
|
|
movm.l (%sp)+,&0x00fc # restore d2-d7
|
| 261 |
|
|
unlk %a6
|
| 262 |
|
|
# EPILOGUE END ##########################################################
|
| 263 |
|
|
|
| 264 |
|
|
divu.w &0x0,%d0 # force a divbyzero exception
|
| 265 |
|
|
rts
|
| 266 |
|
|
|
| 267 |
|
|
###########################################################################
|
| 268 |
|
|
#########################################################################
|
| 269 |
|
|
# This routine uses the 'classical' Algorithm D from Donald Knuth's #
|
| 270 |
|
|
# Art of Computer Programming, vol II, Seminumerical Algorithms. #
|
| 271 |
|
|
# For this implementation b=2**16, and the target is U1U2U3U4/V1V2, #
|
| 272 |
|
|
# where U,V are words of the quadword dividend and longword divisor, #
|
| 273 |
|
|
# and U1, V1 are the most significant words. #
|
| 274 |
|
|
# #
|
| 275 |
|
|
# The most sig. longword of the 64 bit dividend must be in %d5, least #
|
| 276 |
|
|
# in %d6. The divisor must be in the variable ddivisor, and the #
|
| 277 |
|
|
# signed/unsigned flag ddusign must be set (0=unsigned,1=signed). #
|
| 278 |
|
|
# The quotient is returned in %d6, remainder in %d5, unless the #
|
| 279 |
|
|
# v (overflow) bit is set in the saved %ccr. If overflow, the dividend #
|
| 280 |
|
|
# is unchanged. #
|
| 281 |
|
|
#########################################################################
|
| 282 |
|
|
ldclassical:
|
| 283 |
|
|
# if the divisor msw is 0, use simpler algorithm then the full blown
|
| 284 |
|
|
# one at ddknuth:
|
| 285 |
|
|
|
| 286 |
|
|
cmpi.l %d7, &0xffff
|
| 287 |
|
|
bhi.b lddknuth # go use D. Knuth algorithm
|
| 288 |
|
|
|
| 289 |
|
|
# Since the divisor is only a word (and larger than the mslw of the dividend),
|
| 290 |
|
|
# a simpler algorithm may be used :
|
| 291 |
|
|
# In the general case, four quotient words would be created by
|
| 292 |
|
|
# dividing the divisor word into each dividend word. In this case,
|
| 293 |
|
|
# the first two quotient words must be zero, or overflow would occur.
|
| 294 |
|
|
# Since we already checked this case above, we can treat the most significant
|
| 295 |
|
|
# longword of the dividend as (0) remainder (see Knuth) and merely complete
|
| 296 |
|
|
# the last two divisions to get a quotient longword and word remainder:
|
| 297 |
|
|
|
| 298 |
|
|
clr.l %d1
|
| 299 |
|
|
swap %d5 # same as r*b if previous step rqd
|
| 300 |
|
|
swap %d6 # get u3 to lsw position
|
| 301 |
|
|
mov.w %d6, %d5 # rb + u3
|
| 302 |
|
|
|
| 303 |
|
|
divu.w %d7, %d5
|
| 304 |
|
|
|
| 305 |
|
|
mov.w %d5, %d1 # first quotient word
|
| 306 |
|
|
swap %d6 # get u4
|
| 307 |
|
|
mov.w %d6, %d5 # rb + u4
|
| 308 |
|
|
|
| 309 |
|
|
divu.w %d7, %d5
|
| 310 |
|
|
|
| 311 |
|
|
swap %d1
|
| 312 |
|
|
mov.w %d5, %d1 # 2nd quotient 'digit'
|
| 313 |
|
|
clr.w %d5
|
| 314 |
|
|
swap %d5 # now remainder
|
| 315 |
|
|
mov.l %d1, %d6 # and quotient
|
| 316 |
|
|
|
| 317 |
|
|
rts
|
| 318 |
|
|
|
| 319 |
|
|
lddknuth:
|
| 320 |
|
|
# In this algorithm, the divisor is treated as a 2 digit (word) number
|
| 321 |
|
|
# which is divided into a 3 digit (word) dividend to get one quotient
|
| 322 |
|
|
# digit (word). After subtraction, the dividend is shifted and the
|
| 323 |
|
|
# process repeated. Before beginning, the divisor and quotient are
|
| 324 |
|
|
# 'normalized' so that the process of estimating the quotient digit
|
| 325 |
|
|
# will yield verifiably correct results..
|
| 326 |
|
|
|
| 327 |
|
|
clr.l DDNORMAL(%a6) # count of shifts for normalization
|
| 328 |
|
|
clr.b DDSECOND(%a6) # clear flag for quotient digits
|
| 329 |
|
|
clr.l %d1 # %d1 will hold trial quotient
|
| 330 |
|
|
lddnchk:
|
| 331 |
|
|
btst &31, %d7 # must we normalize? first word of
|
| 332 |
|
|
bne.b lddnormalized # divisor (V1) must be >= 65536/2
|
| 333 |
|
|
addq.l &0x1, DDNORMAL(%a6) # count normalization shifts
|
| 334 |
|
|
lsl.l &0x1, %d7 # shift the divisor
|
| 335 |
|
|
lsl.l &0x1, %d6 # shift u4,u3 with overflow to u2
|
| 336 |
|
|
roxl.l &0x1, %d5 # shift u1,u2
|
| 337 |
|
|
bra.w lddnchk
|
| 338 |
|
|
lddnormalized:
|
| 339 |
|
|
|
| 340 |
|
|
# Now calculate an estimate of the quotient words (msw first, then lsw).
|
| 341 |
|
|
# The comments use subscripts for the first quotient digit determination.
|
| 342 |
|
|
mov.l %d7, %d3 # divisor
|
| 343 |
|
|
mov.l %d5, %d2 # dividend mslw
|
| 344 |
|
|
swap %d2
|
| 345 |
|
|
swap %d3
|
| 346 |
|
|
cmp.w %d2, %d3 # V1 = U1 ?
|
| 347 |
|
|
bne.b lddqcalc1
|
| 348 |
|
|
mov.w &0xffff, %d1 # use max trial quotient word
|
| 349 |
|
|
bra.b lddadj0
|
| 350 |
|
|
lddqcalc1:
|
| 351 |
|
|
mov.l %d5, %d1
|
| 352 |
|
|
|
| 353 |
|
|
divu.w %d3, %d1 # use quotient of mslw/msw
|
| 354 |
|
|
|
| 355 |
|
|
andi.l &0x0000ffff, %d1 # zero any remainder
|
| 356 |
|
|
lddadj0:
|
| 357 |
|
|
|
| 358 |
|
|
# now test the trial quotient and adjust. This step plus the
|
| 359 |
|
|
# normalization assures (according to Knuth) that the trial
|
| 360 |
|
|
# quotient will be at worst 1 too large.
|
| 361 |
|
|
mov.l %d6, -(%sp)
|
| 362 |
|
|
clr.w %d6 # word u3 left
|
| 363 |
|
|
swap %d6 # in lsw position
|
| 364 |
|
|
lddadj1: mov.l %d7, %d3
|
| 365 |
|
|
mov.l %d1, %d2
|
| 366 |
|
|
mulu.w %d7, %d2 # V2q
|
| 367 |
|
|
swap %d3
|
| 368 |
|
|
mulu.w %d1, %d3 # V1q
|
| 369 |
|
|
mov.l %d5, %d4 # U1U2
|
| 370 |
|
|
sub.l %d3, %d4 # U1U2 - V1q
|
| 371 |
|
|
|
| 372 |
|
|
swap %d4
|
| 373 |
|
|
|
| 374 |
|
|
mov.w %d4,%d0
|
| 375 |
|
|
mov.w %d6,%d4 # insert lower word (U3)
|
| 376 |
|
|
|
| 377 |
|
|
tst.w %d0 # is upper word set?
|
| 378 |
|
|
bne.w lddadjd1
|
| 379 |
|
|
|
| 380 |
|
|
# add.l %d6, %d4 # (U1U2 - V1q) + U3
|
| 381 |
|
|
|
| 382 |
|
|
cmp.l %d2, %d4
|
| 383 |
|
|
bls.b lddadjd1 # is V2q > (U1U2-V1q) + U3 ?
|
| 384 |
|
|
subq.l &0x1, %d1 # yes, decrement and recheck
|
| 385 |
|
|
bra.b lddadj1
|
| 386 |
|
|
lddadjd1:
|
| 387 |
|
|
# now test the word by multiplying it by the divisor (V1V2) and comparing
|
| 388 |
|
|
# the 3 digit (word) result with the current dividend words
|
| 389 |
|
|
mov.l %d5, -(%sp) # save %d5 (%d6 already saved)
|
| 390 |
|
|
mov.l %d1, %d6
|
| 391 |
|
|
swap %d6 # shift answer to ms 3 words
|
| 392 |
|
|
mov.l %d7, %d5
|
| 393 |
|
|
bsr.l ldmm2
|
| 394 |
|
|
mov.l %d5, %d2 # now %d2,%d3 are trial*divisor
|
| 395 |
|
|
mov.l %d6, %d3
|
| 396 |
|
|
mov.l (%sp)+, %d5 # restore dividend
|
| 397 |
|
|
mov.l (%sp)+, %d6
|
| 398 |
|
|
sub.l %d3, %d6
|
| 399 |
|
|
subx.l %d2, %d5 # subtract double precision
|
| 400 |
|
|
bcc ldd2nd # no carry, do next quotient digit
|
| 401 |
|
|
subq.l &0x1, %d1 # q is one too large
|
| 402 |
|
|
# need to add back divisor longword to current ms 3 digits of dividend
|
| 403 |
|
|
# - according to Knuth, this is done only 2 out of 65536 times for random
|
| 404 |
|
|
# divisor, dividend selection.
|
| 405 |
|
|
clr.l %d2
|
| 406 |
|
|
mov.l %d7, %d3
|
| 407 |
|
|
swap %d3
|
| 408 |
|
|
clr.w %d3 # %d3 now ls word of divisor
|
| 409 |
|
|
add.l %d3, %d6 # aligned with 3rd word of dividend
|
| 410 |
|
|
addx.l %d2, %d5
|
| 411 |
|
|
mov.l %d7, %d3
|
| 412 |
|
|
clr.w %d3 # %d3 now ms word of divisor
|
| 413 |
|
|
swap %d3 # aligned with 2nd word of dividend
|
| 414 |
|
|
add.l %d3, %d5
|
| 415 |
|
|
ldd2nd:
|
| 416 |
|
|
tst.b DDSECOND(%a6) # both q words done?
|
| 417 |
|
|
bne.b lddremain
|
| 418 |
|
|
# first quotient digit now correct. store digit and shift the
|
| 419 |
|
|
# (subtracted) dividend
|
| 420 |
|
|
mov.w %d1, DDQUOTIENT(%a6)
|
| 421 |
|
|
clr.l %d1
|
| 422 |
|
|
swap %d5
|
| 423 |
|
|
swap %d6
|
| 424 |
|
|
mov.w %d6, %d5
|
| 425 |
|
|
clr.w %d6
|
| 426 |
|
|
st DDSECOND(%a6) # second digit
|
| 427 |
|
|
bra.w lddnormalized
|
| 428 |
|
|
lddremain:
|
| 429 |
|
|
# add 2nd word to quotient, get the remainder.
|
| 430 |
|
|
mov.w %d1, DDQUOTIENT+2(%a6)
|
| 431 |
|
|
# shift down one word/digit to renormalize remainder.
|
| 432 |
|
|
mov.w %d5, %d6
|
| 433 |
|
|
swap %d6
|
| 434 |
|
|
swap %d5
|
| 435 |
|
|
mov.l DDNORMAL(%a6), %d7 # get norm shift count
|
| 436 |
|
|
beq.b lddrn
|
| 437 |
|
|
subq.l &0x1, %d7 # set for loop count
|
| 438 |
|
|
lddnlp:
|
| 439 |
|
|
lsr.l &0x1, %d5 # shift into %d6
|
| 440 |
|
|
roxr.l &0x1, %d6
|
| 441 |
|
|
dbf %d7, lddnlp
|
| 442 |
|
|
lddrn:
|
| 443 |
|
|
mov.l %d6, %d5 # remainder
|
| 444 |
|
|
mov.l DDQUOTIENT(%a6), %d6 # quotient
|
| 445 |
|
|
|
| 446 |
|
|
rts
|
| 447 |
|
|
ldmm2:
|
| 448 |
|
|
# factors for the 32X32->64 multiplication are in %d5 and %d6.
|
| 449 |
|
|
# returns 64 bit result in %d5 (hi) %d6(lo).
|
| 450 |
|
|
# destroys %d2,%d3,%d4.
|
| 451 |
|
|
|
| 452 |
|
|
# multiply hi,lo words of each factor to get 4 intermediate products
|
| 453 |
|
|
mov.l %d6, %d2
|
| 454 |
|
|
mov.l %d6, %d3
|
| 455 |
|
|
mov.l %d5, %d4
|
| 456 |
|
|
swap %d3
|
| 457 |
|
|
swap %d4
|
| 458 |
|
|
mulu.w %d5, %d6 # %d6 <- lsw*lsw
|
| 459 |
|
|
mulu.w %d3, %d5 # %d5 <- msw-dest*lsw-source
|
| 460 |
|
|
mulu.w %d4, %d2 # %d2 <- msw-source*lsw-dest
|
| 461 |
|
|
mulu.w %d4, %d3 # %d3 <- msw*msw
|
| 462 |
|
|
# now use swap and addx to consolidate to two longwords
|
| 463 |
|
|
clr.l %d4
|
| 464 |
|
|
swap %d6
|
| 465 |
|
|
add.w %d5, %d6 # add msw of l*l to lsw of m*l product
|
| 466 |
|
|
addx.w %d4, %d3 # add any carry to m*m product
|
| 467 |
|
|
add.w %d2, %d6 # add in lsw of other m*l product
|
| 468 |
|
|
addx.w %d4, %d3 # add any carry to m*m product
|
| 469 |
|
|
swap %d6 # %d6 is low 32 bits of final product
|
| 470 |
|
|
clr.w %d5
|
| 471 |
|
|
clr.w %d2 # lsw of two mixed products used,
|
| 472 |
|
|
swap %d5 # now use msws of longwords
|
| 473 |
|
|
swap %d2
|
| 474 |
|
|
add.l %d2, %d5
|
| 475 |
|
|
add.l %d3, %d5 # %d5 now ms 32 bits of final product
|
| 476 |
|
|
rts
|
| 477 |
|
|
|
| 478 |
|
|
#########################################################################
|
| 479 |
|
|
# XDEF **************************************************************** #
|
| 480 |
|
|
# _060LSP__imulu64_(): Emulate 64-bit unsigned mul instruction #
|
| 481 |
|
|
# _060LSP__imuls64_(): Emulate 64-bit signed mul instruction. #
|
| 482 |
|
|
# #
|
| 483 |
|
|
# This is the library version which is accessed as a subroutine #
|
| 484 |
|
|
# and therefore does not work exactly like the 680X0 mul{s,u}.l #
|
| 485 |
|
|
# 64-bit multiply instruction. #
|
| 486 |
|
|
# #
|
| 487 |
|
|
# XREF **************************************************************** #
|
| 488 |
|
|
# None #
|
| 489 |
|
|
# #
|
| 490 |
|
|
# INPUT *************************************************************** #
|
| 491 |
|
|
# 0x4(sp) = multiplier #
|
| 492 |
|
|
# 0x8(sp) = multiplicand #
|
| 493 |
|
|
# 0xc(sp) = pointer to location to place 64-bit result #
|
| 494 |
|
|
# #
|
| 495 |
|
|
# OUTPUT ************************************************************** #
|
| 496 |
|
|
# 0xc(sp) = points to location of 64-bit result #
|
| 497 |
|
|
# #
|
| 498 |
|
|
# ALGORITHM *********************************************************** #
|
| 499 |
|
|
# Perform the multiply in pieces using 16x16->32 unsigned #
|
| 500 |
|
|
# multiplies and "add" instructions. #
|
| 501 |
|
|
# Set the condition codes as appropriate before performing an #
|
| 502 |
|
|
# "rts". #
|
| 503 |
|
|
# #
|
| 504 |
|
|
#########################################################################
|
| 505 |
|
|
|
| 506 |
|
|
set MUL64_CC, -4
|
| 507 |
|
|
|
| 508 |
|
|
global _060LSP__imulu64_
|
| 509 |
|
|
_060LSP__imulu64_:
|
| 510 |
|
|
|
| 511 |
|
|
# PROLOGUE BEGIN ########################################################
|
| 512 |
|
|
link.w %a6,&-4
|
| 513 |
|
|
movm.l &0x3800,-(%sp) # save d2-d4
|
| 514 |
|
|
# fmovm.l &0x0,-(%sp) # save no fpregs
|
| 515 |
|
|
# PROLOGUE END ##########################################################
|
| 516 |
|
|
|
| 517 |
|
|
mov.w %cc,MUL64_CC(%a6) # save incoming ccodes
|
| 518 |
|
|
|
| 519 |
|
|
mov.l 0x8(%a6),%d0 # store multiplier in d0
|
| 520 |
|
|
beq.w mulu64_zero # handle zero separately
|
| 521 |
|
|
|
| 522 |
|
|
mov.l 0xc(%a6),%d1 # get multiplicand in d1
|
| 523 |
|
|
beq.w mulu64_zero # handle zero separately
|
| 524 |
|
|
|
| 525 |
|
|
#########################################################################
|
| 526 |
|
|
# 63 32 0 #
|
| 527 |
|
|
# ---------------------------- #
|
| 528 |
|
|
# | hi(mplier) * hi(mplicand)| #
|
| 529 |
|
|
# ---------------------------- #
|
| 530 |
|
|
# ----------------------------- #
|
| 531 |
|
|
# | hi(mplier) * lo(mplicand) | #
|
| 532 |
|
|
# ----------------------------- #
|
| 533 |
|
|
# ----------------------------- #
|
| 534 |
|
|
# | lo(mplier) * hi(mplicand) | #
|
| 535 |
|
|
# ----------------------------- #
|
| 536 |
|
|
# | ----------------------------- #
|
| 537 |
|
|
# --|-- | lo(mplier) * lo(mplicand) | #
|
| 538 |
|
|
# | ----------------------------- #
|
| 539 |
|
|
# ======================================================== #
|
| 540 |
|
|
# -------------------------------------------------------- #
|
| 541 |
|
|
# | hi(result) | lo(result) | #
|
| 542 |
|
|
# -------------------------------------------------------- #
|
| 543 |
|
|
#########################################################################
|
| 544 |
|
|
mulu64_alg:
|
| 545 |
|
|
# load temp registers with operands
|
| 546 |
|
|
mov.l %d0,%d2 # mr in d2
|
| 547 |
|
|
mov.l %d0,%d3 # mr in d3
|
| 548 |
|
|
mov.l %d1,%d4 # md in d4
|
| 549 |
|
|
swap %d3 # hi(mr) in lo d3
|
| 550 |
|
|
swap %d4 # hi(md) in lo d4
|
| 551 |
|
|
|
| 552 |
|
|
# complete necessary multiplies:
|
| 553 |
|
|
mulu.w %d1,%d0 # [1] lo(mr) * lo(md)
|
| 554 |
|
|
mulu.w %d3,%d1 # [2] hi(mr) * lo(md)
|
| 555 |
|
|
mulu.w %d4,%d2 # [3] lo(mr) * hi(md)
|
| 556 |
|
|
mulu.w %d4,%d3 # [4] hi(mr) * hi(md)
|
| 557 |
|
|
|
| 558 |
|
|
# add lo portions of [2],[3] to hi portion of [1].
|
| 559 |
|
|
# add carries produced from these adds to [4].
|
| 560 |
|
|
# lo([1]) is the final lo 16 bits of the result.
|
| 561 |
|
|
clr.l %d4 # load d4 w/ zero value
|
| 562 |
|
|
swap %d0 # hi([1]) <==> lo([1])
|
| 563 |
|
|
add.w %d1,%d0 # hi([1]) + lo([2])
|
| 564 |
|
|
addx.l %d4,%d3 # [4] + carry
|
| 565 |
|
|
add.w %d2,%d0 # hi([1]) + lo([3])
|
| 566 |
|
|
addx.l %d4,%d3 # [4] + carry
|
| 567 |
|
|
swap %d0 # lo([1]) <==> hi([1])
|
| 568 |
|
|
|
| 569 |
|
|
# lo portions of [2],[3] have been added in to final result.
|
| 570 |
|
|
# now, clear lo, put hi in lo reg, and add to [4]
|
| 571 |
|
|
clr.w %d1 # clear lo([2])
|
| 572 |
|
|
clr.w %d2 # clear hi([3])
|
| 573 |
|
|
swap %d1 # hi([2]) in lo d1
|
| 574 |
|
|
swap %d2 # hi([3]) in lo d2
|
| 575 |
|
|
add.l %d2,%d1 # [4] + hi([2])
|
| 576 |
|
|
add.l %d3,%d1 # [4] + hi([3])
|
| 577 |
|
|
|
| 578 |
|
|
# now, grab the condition codes. only one that can be set is 'N'.
|
| 579 |
|
|
# 'N' CAN be set if the operation is unsigned if bit 63 is set.
|
| 580 |
|
|
mov.w MUL64_CC(%a6),%d4
|
| 581 |
|
|
andi.b &0x10,%d4 # keep old 'X' bit
|
| 582 |
|
|
tst.l %d1 # may set 'N' bit
|
| 583 |
|
|
bpl.b mulu64_ddone
|
| 584 |
|
|
ori.b &0x8,%d4 # set 'N' bit
|
| 585 |
|
|
mulu64_ddone:
|
| 586 |
|
|
mov.w %d4,%cc
|
| 587 |
|
|
|
| 588 |
|
|
# here, the result is in d1 and d0. the current strategy is to save
|
| 589 |
|
|
# the values at the location pointed to by a0.
|
| 590 |
|
|
# use movm here to not disturb the condition codes.
|
| 591 |
|
|
mulu64_end:
|
| 592 |
|
|
exg %d1,%d0
|
| 593 |
|
|
movm.l &0x0003,([0x10,%a6]) # save result
|
| 594 |
|
|
|
| 595 |
|
|
# EPILOGUE BEGIN ########################################################
|
| 596 |
|
|
# fmovm.l (%sp)+,&0x0 # restore no fpregs
|
| 597 |
|
|
movm.l (%sp)+,&0x001c # restore d2-d4
|
| 598 |
|
|
unlk %a6
|
| 599 |
|
|
# EPILOGUE END ##########################################################
|
| 600 |
|
|
|
| 601 |
|
|
rts
|
| 602 |
|
|
|
| 603 |
|
|
# one or both of the operands is zero so the result is also zero.
|
| 604 |
|
|
# save the zero result to the register file and set the 'Z' ccode bit.
|
| 605 |
|
|
mulu64_zero:
|
| 606 |
|
|
clr.l %d0
|
| 607 |
|
|
clr.l %d1
|
| 608 |
|
|
|
| 609 |
|
|
mov.w MUL64_CC(%a6),%d4
|
| 610 |
|
|
andi.b &0x10,%d4
|
| 611 |
|
|
ori.b &0x4,%d4
|
| 612 |
|
|
mov.w %d4,%cc # set 'Z' ccode bit
|
| 613 |
|
|
|
| 614 |
|
|
bra.b mulu64_end
|
| 615 |
|
|
|
| 616 |
|
|
##########
|
| 617 |
|
|
# muls.l #
|
| 618 |
|
|
##########
|
| 619 |
|
|
global _060LSP__imuls64_
|
| 620 |
|
|
_060LSP__imuls64_:
|
| 621 |
|
|
|
| 622 |
|
|
# PROLOGUE BEGIN ########################################################
|
| 623 |
|
|
link.w %a6,&-4
|
| 624 |
|
|
movm.l &0x3c00,-(%sp) # save d2-d5
|
| 625 |
|
|
# fmovm.l &0x0,-(%sp) # save no fpregs
|
| 626 |
|
|
# PROLOGUE END ##########################################################
|
| 627 |
|
|
|
| 628 |
|
|
mov.w %cc,MUL64_CC(%a6) # save incoming ccodes
|
| 629 |
|
|
|
| 630 |
|
|
mov.l 0x8(%a6),%d0 # store multiplier in d0
|
| 631 |
|
|
beq.b mulu64_zero # handle zero separately
|
| 632 |
|
|
|
| 633 |
|
|
mov.l 0xc(%a6),%d1 # get multiplicand in d1
|
| 634 |
|
|
beq.b mulu64_zero # handle zero separately
|
| 635 |
|
|
|
| 636 |
|
|
clr.b %d5 # clear sign tag
|
| 637 |
|
|
tst.l %d0 # is multiplier negative?
|
| 638 |
|
|
bge.b muls64_chk_md_sgn # no
|
| 639 |
|
|
neg.l %d0 # make multiplier positive
|
| 640 |
|
|
|
| 641 |
|
|
ori.b &0x1,%d5 # save multiplier sgn
|
| 642 |
|
|
|
| 643 |
|
|
# the result sign is the exclusive or of the operand sign bits.
|
| 644 |
|
|
muls64_chk_md_sgn:
|
| 645 |
|
|
tst.l %d1 # is multiplicand negative?
|
| 646 |
|
|
bge.b muls64_alg # no
|
| 647 |
|
|
neg.l %d1 # make multiplicand positive
|
| 648 |
|
|
|
| 649 |
|
|
eori.b &0x1,%d5 # calculate correct sign
|
| 650 |
|
|
|
| 651 |
|
|
#########################################################################
|
| 652 |
|
|
# 63 32 0 #
|
| 653 |
|
|
# ---------------------------- #
|
| 654 |
|
|
# | hi(mplier) * hi(mplicand)| #
|
| 655 |
|
|
# ---------------------------- #
|
| 656 |
|
|
# ----------------------------- #
|
| 657 |
|
|
# | hi(mplier) * lo(mplicand) | #
|
| 658 |
|
|
# ----------------------------- #
|
| 659 |
|
|
# ----------------------------- #
|
| 660 |
|
|
# | lo(mplier) * hi(mplicand) | #
|
| 661 |
|
|
# ----------------------------- #
|
| 662 |
|
|
# | ----------------------------- #
|
| 663 |
|
|
# --|-- | lo(mplier) * lo(mplicand) | #
|
| 664 |
|
|
# | ----------------------------- #
|
| 665 |
|
|
# ======================================================== #
|
| 666 |
|
|
# -------------------------------------------------------- #
|
| 667 |
|
|
# | hi(result) | lo(result) | #
|
| 668 |
|
|
# -------------------------------------------------------- #
|
| 669 |
|
|
#########################################################################
|
| 670 |
|
|
muls64_alg:
|
| 671 |
|
|
# load temp registers with operands
|
| 672 |
|
|
mov.l %d0,%d2 # mr in d2
|
| 673 |
|
|
mov.l %d0,%d3 # mr in d3
|
| 674 |
|
|
mov.l %d1,%d4 # md in d4
|
| 675 |
|
|
swap %d3 # hi(mr) in lo d3
|
| 676 |
|
|
swap %d4 # hi(md) in lo d4
|
| 677 |
|
|
|
| 678 |
|
|
# complete necessary multiplies:
|
| 679 |
|
|
mulu.w %d1,%d0 # [1] lo(mr) * lo(md)
|
| 680 |
|
|
mulu.w %d3,%d1 # [2] hi(mr) * lo(md)
|
| 681 |
|
|
mulu.w %d4,%d2 # [3] lo(mr) * hi(md)
|
| 682 |
|
|
mulu.w %d4,%d3 # [4] hi(mr) * hi(md)
|
| 683 |
|
|
|
| 684 |
|
|
# add lo portions of [2],[3] to hi portion of [1].
|
| 685 |
|
|
# add carries produced from these adds to [4].
|
| 686 |
|
|
# lo([1]) is the final lo 16 bits of the result.
|
| 687 |
|
|
clr.l %d4 # load d4 w/ zero value
|
| 688 |
|
|
swap %d0 # hi([1]) <==> lo([1])
|
| 689 |
|
|
add.w %d1,%d0 # hi([1]) + lo([2])
|
| 690 |
|
|
addx.l %d4,%d3 # [4] + carry
|
| 691 |
|
|
add.w %d2,%d0 # hi([1]) + lo([3])
|
| 692 |
|
|
addx.l %d4,%d3 # [4] + carry
|
| 693 |
|
|
swap %d0 # lo([1]) <==> hi([1])
|
| 694 |
|
|
|
| 695 |
|
|
# lo portions of [2],[3] have been added in to final result.
|
| 696 |
|
|
# now, clear lo, put hi in lo reg, and add to [4]
|
| 697 |
|
|
clr.w %d1 # clear lo([2])
|
| 698 |
|
|
clr.w %d2 # clear hi([3])
|
| 699 |
|
|
swap %d1 # hi([2]) in lo d1
|
| 700 |
|
|
swap %d2 # hi([3]) in lo d2
|
| 701 |
|
|
add.l %d2,%d1 # [4] + hi([2])
|
| 702 |
|
|
add.l %d3,%d1 # [4] + hi([3])
|
| 703 |
|
|
|
| 704 |
|
|
tst.b %d5 # should result be signed?
|
| 705 |
|
|
beq.b muls64_done # no
|
| 706 |
|
|
|
| 707 |
|
|
# result should be a signed negative number.
|
| 708 |
|
|
# compute 2's complement of the unsigned number:
|
| 709 |
|
|
# -negate all bits and add 1
|
| 710 |
|
|
muls64_neg:
|
| 711 |
|
|
not.l %d0 # negate lo(result) bits
|
| 712 |
|
|
not.l %d1 # negate hi(result) bits
|
| 713 |
|
|
addq.l &1,%d0 # add 1 to lo(result)
|
| 714 |
|
|
addx.l %d4,%d1 # add carry to hi(result)
|
| 715 |
|
|
|
| 716 |
|
|
muls64_done:
|
| 717 |
|
|
mov.w MUL64_CC(%a6),%d4
|
| 718 |
|
|
andi.b &0x10,%d4 # keep old 'X' bit
|
| 719 |
|
|
tst.l %d1 # may set 'N' bit
|
| 720 |
|
|
bpl.b muls64_ddone
|
| 721 |
|
|
ori.b &0x8,%d4 # set 'N' bit
|
| 722 |
|
|
muls64_ddone:
|
| 723 |
|
|
mov.w %d4,%cc
|
| 724 |
|
|
|
| 725 |
|
|
# here, the result is in d1 and d0. the current strategy is to save
|
| 726 |
|
|
# the values at the location pointed to by a0.
|
| 727 |
|
|
# use movm here to not disturb the condition codes.
|
| 728 |
|
|
muls64_end:
|
| 729 |
|
|
exg %d1,%d0
|
| 730 |
|
|
movm.l &0x0003,([0x10,%a6]) # save result at (a0)
|
| 731 |
|
|
|
| 732 |
|
|
# EPILOGUE BEGIN ########################################################
|
| 733 |
|
|
# fmovm.l (%sp)+,&0x0 # restore no fpregs
|
| 734 |
|
|
movm.l (%sp)+,&0x003c # restore d2-d5
|
| 735 |
|
|
unlk %a6
|
| 736 |
|
|
# EPILOGUE END ##########################################################
|
| 737 |
|
|
|
| 738 |
|
|
rts
|
| 739 |
|
|
|
| 740 |
|
|
# one or both of the operands is zero so the result is also zero.
|
| 741 |
|
|
# save the zero result to the register file and set the 'Z' ccode bit.
|
| 742 |
|
|
muls64_zero:
|
| 743 |
|
|
clr.l %d0
|
| 744 |
|
|
clr.l %d1
|
| 745 |
|
|
|
| 746 |
|
|
mov.w MUL64_CC(%a6),%d4
|
| 747 |
|
|
andi.b &0x10,%d4
|
| 748 |
|
|
ori.b &0x4,%d4
|
| 749 |
|
|
mov.w %d4,%cc # set 'Z' ccode bit
|
| 750 |
|
|
|
| 751 |
|
|
bra.b muls64_end
|
| 752 |
|
|
|
| 753 |
|
|
#########################################################################
|
| 754 |
|
|
# XDEF **************************************************************** #
|
| 755 |
|
|
# _060LSP__cmp2_Ab_(): Emulate "cmp2.b An,". #
|
| 756 |
|
|
# _060LSP__cmp2_Aw_(): Emulate "cmp2.w An,". #
|
| 757 |
|
|
# _060LSP__cmp2_Al_(): Emulate "cmp2.l An,". #
|
| 758 |
|
|
# _060LSP__cmp2_Db_(): Emulate "cmp2.b Dn,". #
|
| 759 |
|
|
# _060LSP__cmp2_Dw_(): Emulate "cmp2.w Dn,". #
|
| 760 |
|
|
# _060LSP__cmp2_Dl_(): Emulate "cmp2.l Dn,". #
|
| 761 |
|
|
# #
|
| 762 |
|
|
# This is the library version which is accessed as a subroutine #
|
| 763 |
|
|
# and therefore does not work exactly like the 680X0 "cmp2" #
|
| 764 |
|
|
# instruction. #
|
| 765 |
|
|
# #
|
| 766 |
|
|
# XREF **************************************************************** #
|
| 767 |
|
|
# None #
|
| 768 |
|
|
# #
|
| 769 |
|
|
# INPUT *************************************************************** #
|
| 770 |
|
|
# 0x4(sp) = Rn #
|
| 771 |
|
|
# 0x8(sp) = pointer to boundary pair #
|
| 772 |
|
|
# #
|
| 773 |
|
|
# OUTPUT ************************************************************** #
|
| 774 |
|
|
# cc = condition codes are set correctly #
|
| 775 |
|
|
# #
|
| 776 |
|
|
# ALGORITHM *********************************************************** #
|
| 777 |
|
|
# In the interest of simplicity, all operands are converted to #
|
| 778 |
|
|
# longword size whether the operation is byte, word, or long. The #
|
| 779 |
|
|
# bounds are sign extended accordingly. If Rn is a data regsiter, Rn is #
|
| 780 |
|
|
# also sign extended. If Rn is an address register, it need not be sign #
|
| 781 |
|
|
# extended since the full register is always used. #
|
| 782 |
|
|
# The condition codes are set correctly before the final "rts". #
|
| 783 |
|
|
# #
|
| 784 |
|
|
#########################################################################
|
| 785 |
|
|
|
| 786 |
|
|
set CMP2_CC, -4
|
| 787 |
|
|
|
| 788 |
|
|
global _060LSP__cmp2_Ab_
|
| 789 |
|
|
_060LSP__cmp2_Ab_:
|
| 790 |
|
|
|
| 791 |
|
|
# PROLOGUE BEGIN ########################################################
|
| 792 |
|
|
link.w %a6,&-4
|
| 793 |
|
|
movm.l &0x3800,-(%sp) # save d2-d4
|
| 794 |
|
|
# fmovm.l &0x0,-(%sp) # save no fpregs
|
| 795 |
|
|
# PROLOGUE END ##########################################################
|
| 796 |
|
|
|
| 797 |
|
|
mov.w %cc,CMP2_CC(%a6)
|
| 798 |
|
|
mov.l 0x8(%a6), %d2 # get regval
|
| 799 |
|
|
|
| 800 |
|
|
mov.b ([0xc,%a6],0x0),%d0
|
| 801 |
|
|
mov.b ([0xc,%a6],0x1),%d1
|
| 802 |
|
|
|
| 803 |
|
|
extb.l %d0 # sign extend lo bnd
|
| 804 |
|
|
extb.l %d1 # sign extend hi bnd
|
| 805 |
|
|
bra.w l_cmp2_cmp # go do the compare emulation
|
| 806 |
|
|
|
| 807 |
|
|
global _060LSP__cmp2_Aw_
|
| 808 |
|
|
_060LSP__cmp2_Aw_:
|
| 809 |
|
|
|
| 810 |
|
|
# PROLOGUE BEGIN ########################################################
|
| 811 |
|
|
link.w %a6,&-4
|
| 812 |
|
|
movm.l &0x3800,-(%sp) # save d2-d4
|
| 813 |
|
|
# fmovm.l &0x0,-(%sp) # save no fpregs
|
| 814 |
|
|
# PROLOGUE END ##########################################################
|
| 815 |
|
|
|
| 816 |
|
|
mov.w %cc,CMP2_CC(%a6)
|
| 817 |
|
|
mov.l 0x8(%a6), %d2 # get regval
|
| 818 |
|
|
|
| 819 |
|
|
mov.w ([0xc,%a6],0x0),%d0
|
| 820 |
|
|
mov.w ([0xc,%a6],0x2),%d1
|
| 821 |
|
|
|
| 822 |
|
|
ext.l %d0 # sign extend lo bnd
|
| 823 |
|
|
ext.l %d1 # sign extend hi bnd
|
| 824 |
|
|
bra.w l_cmp2_cmp # go do the compare emulation
|
| 825 |
|
|
|
| 826 |
|
|
global _060LSP__cmp2_Al_
|
| 827 |
|
|
_060LSP__cmp2_Al_:
|
| 828 |
|
|
|
| 829 |
|
|
# PROLOGUE BEGIN ########################################################
|
| 830 |
|
|
link.w %a6,&-4
|
| 831 |
|
|
movm.l &0x3800,-(%sp) # save d2-d4
|
| 832 |
|
|
# fmovm.l &0x0,-(%sp) # save no fpregs
|
| 833 |
|
|
# PROLOGUE END ##########################################################
|
| 834 |
|
|
|
| 835 |
|
|
mov.w %cc,CMP2_CC(%a6)
|
| 836 |
|
|
mov.l 0x8(%a6), %d2 # get regval
|
| 837 |
|
|
|
| 838 |
|
|
mov.l ([0xc,%a6],0x0),%d0
|
| 839 |
|
|
mov.l ([0xc,%a6],0x4),%d1
|
| 840 |
|
|
bra.w l_cmp2_cmp # go do the compare emulation
|
| 841 |
|
|
|
| 842 |
|
|
global _060LSP__cmp2_Db_
|
| 843 |
|
|
_060LSP__cmp2_Db_:
|
| 844 |
|
|
|
| 845 |
|
|
# PROLOGUE BEGIN ########################################################
|
| 846 |
|
|
link.w %a6,&-4
|
| 847 |
|
|
movm.l &0x3800,-(%sp) # save d2-d4
|
| 848 |
|
|
# fmovm.l &0x0,-(%sp) # save no fpregs
|
| 849 |
|
|
# PROLOGUE END ##########################################################
|
| 850 |
|
|
|
| 851 |
|
|
mov.w %cc,CMP2_CC(%a6)
|
| 852 |
|
|
mov.l 0x8(%a6), %d2 # get regval
|
| 853 |
|
|
|
| 854 |
|
|
mov.b ([0xc,%a6],0x0),%d0
|
| 855 |
|
|
mov.b ([0xc,%a6],0x1),%d1
|
| 856 |
|
|
|
| 857 |
|
|
extb.l %d0 # sign extend lo bnd
|
| 858 |
|
|
extb.l %d1 # sign extend hi bnd
|
| 859 |
|
|
|
| 860 |
|
|
# operation is a data register compare.
|
| 861 |
|
|
# sign extend byte to long so we can do simple longword compares.
|
| 862 |
|
|
extb.l %d2 # sign extend data byte
|
| 863 |
|
|
bra.w l_cmp2_cmp # go do the compare emulation
|
| 864 |
|
|
|
| 865 |
|
|
global _060LSP__cmp2_Dw_
|
| 866 |
|
|
_060LSP__cmp2_Dw_:
|
| 867 |
|
|
|
| 868 |
|
|
# PROLOGUE BEGIN ########################################################
|
| 869 |
|
|
link.w %a6,&-4
|
| 870 |
|
|
movm.l &0x3800,-(%sp) # save d2-d4
|
| 871 |
|
|
# fmovm.l &0x0,-(%sp) # save no fpregs
|
| 872 |
|
|
# PROLOGUE END ##########################################################
|
| 873 |
|
|
|
| 874 |
|
|
mov.w %cc,CMP2_CC(%a6)
|
| 875 |
|
|
mov.l 0x8(%a6), %d2 # get regval
|
| 876 |
|
|
|
| 877 |
|
|
mov.w ([0xc,%a6],0x0),%d0
|
| 878 |
|
|
mov.w ([0xc,%a6],0x2),%d1
|
| 879 |
|
|
|
| 880 |
|
|
ext.l %d0 # sign extend lo bnd
|
| 881 |
|
|
ext.l %d1 # sign extend hi bnd
|
| 882 |
|
|
|
| 883 |
|
|
# operation is a data register compare.
|
| 884 |
|
|
# sign extend word to long so we can do simple longword compares.
|
| 885 |
|
|
ext.l %d2 # sign extend data word
|
| 886 |
|
|
bra.w l_cmp2_cmp # go emulate compare
|
| 887 |
|
|
|
| 888 |
|
|
global _060LSP__cmp2_Dl_
|
| 889 |
|
|
_060LSP__cmp2_Dl_:
|
| 890 |
|
|
|
| 891 |
|
|
# PROLOGUE BEGIN ########################################################
|
| 892 |
|
|
link.w %a6,&-4
|
| 893 |
|
|
movm.l &0x3800,-(%sp) # save d2-d4
|
| 894 |
|
|
# fmovm.l &0x0,-(%sp) # save no fpregs
|
| 895 |
|
|
# PROLOGUE END ##########################################################
|
| 896 |
|
|
|
| 897 |
|
|
mov.w %cc,CMP2_CC(%a6)
|
| 898 |
|
|
mov.l 0x8(%a6), %d2 # get regval
|
| 899 |
|
|
|
| 900 |
|
|
mov.l ([0xc,%a6],0x0),%d0
|
| 901 |
|
|
mov.l ([0xc,%a6],0x4),%d1
|
| 902 |
|
|
|
| 903 |
|
|
#
|
| 904 |
|
|
# To set the ccodes correctly:
|
| 905 |
|
|
# (1) save 'Z' bit from (Rn - lo)
|
| 906 |
|
|
# (2) save 'Z' and 'N' bits from ((hi - lo) - (Rn - hi))
|
| 907 |
|
|
# (3) keep 'X', 'N', and 'V' from before instruction
|
| 908 |
|
|
# (4) combine ccodes
|
| 909 |
|
|
#
|
| 910 |
|
|
l_cmp2_cmp:
|
| 911 |
|
|
sub.l %d0, %d2 # (Rn - lo)
|
| 912 |
|
|
mov.w %cc, %d3 # fetch resulting ccodes
|
| 913 |
|
|
andi.b &0x4, %d3 # keep 'Z' bit
|
| 914 |
|
|
sub.l %d0, %d1 # (hi - lo)
|
| 915 |
|
|
cmp.l %d1,%d2 # ((hi - lo) - (Rn - hi))
|
| 916 |
|
|
|
| 917 |
|
|
mov.w %cc, %d4 # fetch resulting ccodes
|
| 918 |
|
|
or.b %d4, %d3 # combine w/ earlier ccodes
|
| 919 |
|
|
andi.b &0x5, %d3 # keep 'Z' and 'N'
|
| 920 |
|
|
|
| 921 |
|
|
mov.w CMP2_CC(%a6), %d4 # fetch old ccodes
|
| 922 |
|
|
andi.b &0x1a, %d4 # keep 'X','N','V' bits
|
| 923 |
|
|
or.b %d3, %d4 # insert new ccodes
|
| 924 |
|
|
mov.w %d4,%cc # save new ccodes
|
| 925 |
|
|
|
| 926 |
|
|
# EPILOGUE BEGIN ########################################################
|
| 927 |
|
|
# fmovm.l (%sp)+,&0x0 # restore no fpregs
|
| 928 |
|
|
movm.l (%sp)+,&0x001c # restore d2-d4
|
| 929 |
|
|
unlk %a6
|
| 930 |
|
|
# EPILOGUE END ##########################################################
|
| 931 |
|
|
|
| 932 |
|
|
rts
|
