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riscv-gcc-1
Commit 686cada4 by Ian Lance Taylor
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Add MCF5200 support 

From-SVN: r12534
parent a418b6c5
Showing with 895 additions and 28 deletions
gcc/config/m68k/lb1sf68.asm
......@@ -244,12 +244,22 @@ FPTRAP = 15
$_exception_handler:
lea SYM (_fpCCR),a0
movew d7,a0@(EBITS) | set __exception_bits
#ifndef __mcf5200__
orw d7,a0@(STICK) | and __sticky_bits
#else
movew a0@(STICK),d4
orl d7,d4
movew d4,a0@(STICK)
#endif
movew d6,a0@(FORMT) | and __format
movew d5,a0@(LASTO) | and __last_operation
| Now put the operands in place:
#ifndef __mcf5200__
cmpw IMM (SINGLE_FLOAT),d6
#else
cmpl IMM (SINGLE_FLOAT),d6
#endif
beq 1f
movel a6@(8),a0@(OPER1)
movel a6@(12),a0@(OPER1+4)
......@@ -260,7 +270,13 @@ $_exception_handler:
movel a6@(12),a0@(OPER2)
2:
| And check whether the exception is trap-enabled:
#ifndef __mcf5200__
andw a0@(TRAPE),d7 | is exception trap-enabled?
#else
clrl d6
movew a0@(TRAPE),d6
andl d6,d7
#endif
beq 1f | no, exit
pea SYM (_fpCCR) | yes, push address of _fpCCR
trap IMM (FPTRAP) | and trap
......@@ -278,7 +294,11 @@ SYM (__mulsi3):
muluw sp@(10), d0 /* x0*y1 */
movew sp@(6), d1 /* x1 -> d1 */
muluw sp@(8), d1 /* x1*y0 */
#ifndef __mcf5200__
addw d1, d0
#else
addl d1, d0
#endif
swap d0
clrw d0
movew sp@(6), d1 /* x1 -> d1 */
......@@ -293,6 +313,7 @@ SYM (__mulsi3):
.proc
.globl SYM (__udivsi3)
SYM (__udivsi3):
#ifndef __mcf5200__
movel d2, sp@-
movel sp@(12), d1 /* d1 = divisor */
movel sp@(8), d0 /* d0 = dividend */
......@@ -336,6 +357,31 @@ L5: subql IMM (1), d0 /* adjust quotient */
L6: movel sp@+, d2
rts
#else /* __mcf5200__ */
/* Coldfire implementation of non-restoring division algorithm from
Hennessy & Patterson, Appendix A. */
link a6,IMM (0)
moveml d2-d4,sp@-
movel a6@(8),d0
movel a6@(12),d1
clrl d2 | clear p
moveq IMM (31),d4
L1: addl d0,d0 | shift reg pair (p,a) one bit left
addxl d2,d2
movl d2,d3 | subtract b from p, store in tmp.
subl d1,d3
jmi L2 | if the result is not is negative, set the
bset #0,d0 | low order bit of a to 1 and store tmp in p.
movl d3,d2
L2: subql IMM (1),d4
jcc L1
moveml sp@+,d2-d4 | restore data registers
unlk a6 | and return
rts
#endif /* __mcf5200__ */
#endif /* L_udivsi3 */
#ifdef L_divsi3
......@@ -345,15 +391,23 @@ L6: movel sp@+, d2
SYM (__divsi3):
movel d2, sp@-
moveb IMM (1), d2 /* sign of result stored in d2 (=1 or =-1) */
moveq IMM (1), d2 /* sign of result stored in d2 (=1 or =-1) */
movel sp@(12), d1 /* d1 = divisor */
jpl L1
negl d1
#ifndef __mcf5200__
negb d2 /* change sign because divisor <0 */
#else
negl d2 /* change sign because divisor <0 */
#endif
L1: movel sp@(8), d0 /* d0 = dividend */
jpl L2
negl d0
#ifndef __mcf5200__
negb d2
#else
negl d2
#endif
L2: movel d1, sp@-
movel d0, sp@-
......@@ -467,7 +521,7 @@ Ld$den:
| Return and signal a denormalized number
orl d7,d0
movew IMM (INEXACT_RESULT+UNDERFLOW),d7
movew IMM (DOUBLE_FLOAT),d6
moveq IMM (DOUBLE_FLOAT),d6
jmp $_exception_handler
Ld$infty:
......@@ -477,7 +531,7 @@ Ld$overflow:
movel IMM (0),d1
orl d7,d0
movew IMM (INEXACT_RESULT+OVERFLOW),d7
movew IMM (DOUBLE_FLOAT),d6
moveq IMM (DOUBLE_FLOAT),d6
jmp $_exception_handler
Ld$underflow:
......@@ -485,7 +539,7 @@ Ld$underflow:
movel IMM (0),d0
movel d0,d1
movew IMM (INEXACT_RESULT+UNDERFLOW),d7
movew IMM (DOUBLE_FLOAT),d6
moveq IMM (DOUBLE_FLOAT),d6
jmp $_exception_handler
Ld$inop:
......@@ -493,7 +547,7 @@ Ld$inop:
movel IMM (QUIET_NaN),d0
movel d0,d1
movew IMM (INEXACT_RESULT+INVALID_OPERATION),d7
movew IMM (DOUBLE_FLOAT),d6
moveq IMM (DOUBLE_FLOAT),d6
jmp $_exception_handler
Ld$div$0:
......@@ -502,7 +556,7 @@ Ld$div$0:
movel IMM (0),d1
orl d7,d0
movew IMM (INEXACT_RESULT+DIVIDE_BY_ZERO),d7
movew IMM (DOUBLE_FLOAT),d6
moveq IMM (DOUBLE_FLOAT),d6
jmp $_exception_handler
|=============================================================================
......@@ -558,10 +612,15 @@ SYM (__adddf3):
andl IMM (0x80000000),d7 | isolate a's sign bit '
swap d6 | and also b's sign bit '
#ifndef __mcf5200__
andw IMM (0x8000),d6 |
orw d6,d7 | and combine them into d7, so that a's sign '
| bit is in the high word and b's is in the '
| low word, so d6 is free to be used
#else
andl IMM (0x8000),d6
orl d6,d7
#endif
movel d7,a0 | now save d7 into a0, so d7 is free to
| be used also
......@@ -580,7 +639,11 @@ SYM (__adddf3):
orl d7,d0 | and put hidden bit back
Ladddf$1:
swap d4 | shift right exponent so that it starts
#ifndef __mcf5200__
lsrw IMM (5),d4 | in bit 0 and not bit 20
#else
lsrl IMM (5),d4 | in bit 0 and not bit 20
#endif
| Now we have a's exponent in d4 and fraction in d0-d1 '
movel d2,d5 | save b to get exponent
andl d6,d5 | get exponent in d5
......@@ -592,7 +655,11 @@ Ladddf$1:
orl d7,d2 | and put hidden bit back
Ladddf$2:
swap d5 | shift right exponent so that it starts
#ifndef __mcf5200__
lsrw IMM (5),d5 | in bit 0 and not bit 20
#else
lsrl IMM (5),d5 | in bit 0 and not bit 20
#endif
| Now we have b's exponent in d5 and fraction in d2-d3. '
......@@ -603,7 +670,11 @@ Ladddf$2:
| and d4-d5-d6-d7 for the second. To do this we store (temporarily) the
| exponents in a2-a3.
#ifndef __mcf5200__
moveml a2-a3,sp@- | save the address registers
#else
moveml a2-a4,sp@- | save the address registers
#endif
movel d4,a2 | save the exponents
movel d5,a3 |
......@@ -617,32 +688,88 @@ Ladddf$2:
| Here we shift the numbers until the exponents are the same, and put
| the largest exponent in a2.
#ifndef __mcf5200__
exg d4,a2 | get exponents back
exg d5,a3 |
cmpw d4,d5 | compare the exponents
#else
movel d4,a4 | get exponents back
movel a2,d4
movel a4,a2
movel d5,a4
movel a3,d5
movel a4,a3
cmpl d4,d5 | compare the exponents
#endif
beq Ladddf$3 | if equal don't shift '
bhi 9f | branch if second exponent is higher
| Here we have a's exponent larger than b's, so we have to shift b. We do
| this by using as counter d2:
1: movew d4,d2 | move largest exponent to d2
#ifndef __mcf5200__
subw d5,d2 | and subtract second exponent
exg d4,a2 | get back the longs we saved
exg d5,a3 |
#else
subl d5,d2 | and subtract second exponent
movel d4,a4 | get back the longs we saved
movel a2,d4
movel a4,a2
movel d5,a4
movel a3,d5
movel a4,a3
#endif
| if difference is too large we don't shift (actually, we can just exit) '
#ifndef __mcf5200__
cmpw IMM (DBL_MANT_DIG+2),d2
#else
cmpl IMM (DBL_MANT_DIG+2),d2
#endif
bge Ladddf$b$small
#ifndef __mcf5200__
cmpw IMM (32),d2 | if difference >= 32, shift by longs
#else
cmpl IMM (32),d2 | if difference >= 32, shift by longs
#endif
bge 5f
2: cmpw IMM (16),d2 | if difference >= 16, shift by words
2:
#ifndef __mcf5200__
cmpw IMM (16),d2 | if difference >= 16, shift by words
#else
cmpl IMM (16),d2 | if difference >= 16, shift by words
#endif
bge 6f
bra 3f | enter dbra loop
4: lsrl IMM (1),d4
4:
#ifndef __mcf5200__
lsrl IMM (1),d4
roxrl IMM (1),d5
roxrl IMM (1),d6
roxrl IMM (1),d7
3: dbra d2,4b
#else
lsrl IMM (1),d7
btst IMM (0),d6
beq 10f
bset IMM (31),d7
10: lsrl IMM (1),d6
btst IMM (0),d5
beq 11f
bset IMM (31),d6
11: lsrl IMM (1),d5
btst IMM (0),d4
beq 12f
bset IMM (31),d5
12: lsrl IMM (1),d4
#endif
3:
#ifndef __mcf5200__
dbra d2,4b
#else
subql IMM (1),d2
bpl 4b
#endif
movel IMM (0),d2
movel d2,d3
bra Ladddf$4
......@@ -651,7 +778,11 @@ Ladddf$2:
movel d5,d6
movel d4,d5
movel IMM (0),d4
#ifndef __mcf5200__
subw IMM (32),d2
#else
subl IMM (32),d2
#endif
bra 2b
6:
movew d6,d7
......@@ -662,28 +793,82 @@ Ladddf$2:
swap d5
movew IMM (0),d4
swap d4
#ifndef __mcf5200__
subw IMM (16),d2
#else
subl IMM (16),d2
#endif
bra 3b
9: exg d4,d5
9:
#ifndef __mcf5200__
exg d4,d5
movew d4,d6
subw d5,d6 | keep d5 (largest exponent) in d4
exg d4,a2
exg d5,a3
#else
movel d5,d6
movel d4,d5
movel d6,d4
subl d5,d6
movel d4,a4
movel a2,d4
movel a4,a2
movel d5,a4
movel a3,d5
movel a4,a3
#endif
| if difference is too large we don't shift (actually, we can just exit) '
#ifndef __mcf5200__
cmpw IMM (DBL_MANT_DIG+2),d6
#else
cmpl IMM (DBL_MANT_DIG+2),d6
#endif
bge Ladddf$a$small
#ifndef __mcf5200__
cmpw IMM (32),d6 | if difference >= 32, shift by longs
#else
cmpl IMM (32),d6 | if difference >= 32, shift by longs
#endif
bge 5f
2: cmpw IMM (16),d6 | if difference >= 16, shift by words
2:
#ifndef __mcf5200__
cmpw IMM (16),d6 | if difference >= 16, shift by words
#else
cmpl IMM (16),d6 | if difference >= 16, shift by words
#endif
bge 6f
bra 3f | enter dbra loop
4: lsrl IMM (1),d0
4:
#ifndef __mcf5200__
lsrl IMM (1),d0
roxrl IMM (1),d1
roxrl IMM (1),d2
roxrl IMM (1),d3
3: dbra d6,4b
#else
lsrl IMM (1),d3
btst IMM (0),d2
beq 10f
bset IMM (31),d3
10: lsrl IMM (1),d2
btst IMM (0),d1
beq 11f
bset IMM (31),d2
11: lsrl IMM (1),d1
btst IMM (0),d0
beq 12f
bset IMM (31),d1
12: lsrl IMM (1),d0
#endif
3:
#ifndef __mcf5200__
dbra d6,4b
#else
subql IMM (1),d6
bpl 4b
#endif
movel IMM (0),d7
movel d7,d6
bra Ladddf$4
......@@ -692,7 +877,11 @@ Ladddf$2:
movel d1,d2
movel d0,d1
movel IMM (0),d0
#ifndef __mcf5200__
subw IMM (32),d6
#else
subl IMM (32),d6
#endif
bra 2b
6:
movew d2,d3
......@@ -703,18 +892,40 @@ Ladddf$2:
swap d1
movew IMM (0),d0
swap d0
#ifndef __mcf5200__
subw IMM (16),d6
#else
subl IMM (16),d6
#endif
bra 3b
Ladddf$3:
#ifndef __mcf5200__
exg d4,a2
exg d5,a3
#else
movel d4,a4
movel a2,d4
movel a4,a2
movel d5,a4
movel a3,d5
movel a4,a3
#endif
Ladddf$4:
| Now we have the numbers in d0--d3 and d4--d7, the exponent in a2, and
| the signs in a4.
| Here we have to decide whether to add or subtract the numbers:
#ifndef __mcf5200__
exg d7,a0 | get the signs
exg d6,a3 | a3 is free to be used
#else
movel d7,a4
movel a0,d7
movel a4,a0
movel d6,a4
movel a3,d6
movel a4,a3
#endif
movel d7,d6 |
movew IMM (0),d7 | get a's sign in d7 '
swap d6 |
......@@ -722,8 +933,17 @@ Ladddf$4:
eorl d7,d6 | compare the signs
bmi Lsubdf$0 | if the signs are different we have
| to subtract
#ifndef __mcf5200__
exg d7,a0 | else we add the numbers
exg d6,a3 |
#else
movel d7,a4
movel a0,d7
movel a4,a0
movel d6,a4
movel a3,d6
movel a4,a3
#endif
addl d7,d3 |
addxl d6,d2 |
addxl d5,d1 |
......@@ -733,7 +953,11 @@ Ladddf$4:
movel a0,d7 |
andl IMM (0x80000000),d7 | d7 now has the sign
#ifndef __mcf5200__
moveml sp@+,a2-a3
#else
moveml sp@+,a2-a4
#endif
| Before rounding normalize so bit #DBL_MANT_DIG is set (we will consider
| the case of denormalized numbers in the rounding routine itself).
......@@ -741,28 +965,64 @@ Ladddf$4:
| one more bit we check this:
btst IMM (DBL_MANT_DIG+1),d0
beq 1f
#ifndef __mcf5200__
lsrl IMM (1),d0
roxrl IMM (1),d1
roxrl IMM (1),d2
roxrl IMM (1),d3
addw IMM (1),d4
#else
lsrl IMM (1),d3
btst IMM (0),d2
beq 10f
bset IMM (31),d3
10: lsrl IMM (1),d2
btst IMM (0),d1
beq 11f
bset IMM (31),d2
11: lsrl IMM (1),d1
btst IMM (0),d0
beq 12f
bset IMM (31),d1
12: lsrl IMM (1),d0
addl IMM (1),d4
#endif
1:
lea Ladddf$5,a0 | to return from rounding routine
lea SYM (_fpCCR),a1 | check the rounding mode
#ifdef __mcf5200__
clrl d6
#endif
movew a1@(6),d6 | rounding mode in d6
beq Lround$to$nearest
#ifndef __mcf5200__
cmpw IMM (ROUND_TO_PLUS),d6
#else
cmpl IMM (ROUND_TO_PLUS),d6
#endif
bhi Lround$to$minus
blt Lround$to$zero
bra Lround$to$plus
Ladddf$5:
| Put back the exponent and check for overflow
#ifndef __mcf5200__
cmpw IMM (0x7ff),d4 | is the exponent big?
#else
cmpl IMM (0x7ff),d4 | is the exponent big?
#endif
bge 1f
bclr IMM (DBL_MANT_DIG-1),d0
#ifndef __mcf5200__
lslw IMM (4),d4 | put exponent back into position
#else
lsll IMM (4),d4 | put exponent back into position
#endif
swap d0 |
#ifndef __mcf5200__
orw d4,d0 |
#else
orl d4,d0 |
#endif
swap d0 |
bra Ladddf$ret
1:
......@@ -771,17 +1031,26 @@ Ladddf$5:
Lsubdf$0:
| Here we do the subtraction.
#ifndef __mcf5200__
exg d7,a0 | put sign back in a0
exg d6,a3 |
#else
movel d7,a4
movel a0,d7
movel a4,a0
movel d6,a4
movel a3,d6
movel a4,a3
#endif
subl d7,d3 |
subxl d6,d2 |
subxl d5,d1 |
subxl d4,d0 |
beq Ladddf$ret$1 | if zero just exit
bpl 1f | if positive skip the following
exg d7,a0 |
movel a0,d7 |
bchg IMM (31),d7 | change sign bit in d7
exg d7,a0 |
movel d7,a0 |
negl d3 |
negxl d2 |
negxl d1 | and negate result
......@@ -790,7 +1059,11 @@ Lsubdf$0:
movel a2,d4 | return exponent to d4
movel a0,d7
andl IMM (0x80000000),d7 | isolate sign bit
#ifndef __mcf5200__
moveml sp@+,a2-a3 |
#else
moveml sp@+,a2-a4 |
#endif
| Before rounding normalize so bit #DBL_MANT_DIG is set (we will consider
| the case of denormalized numbers in the rounding routine itself).
......@@ -798,26 +1071,58 @@ Lsubdf$0:
| one more bit we check this:
btst IMM (DBL_MANT_DIG+1),d0
beq 1f
#ifndef __mcf5200__
lsrl IMM (1),d0
roxrl IMM (1),d1
roxrl IMM (1),d2
roxrl IMM (1),d3
addw IMM (1),d4
#else
lsrl IMM (1),d3
btst IMM (0),d2
beq 10f
bset IMM (31),d3
10: lsrl IMM (1),d2
btst IMM (0),d1
beq 11f
bset IMM (31),d2
11: lsrl IMM (1),d1
btst IMM (0),d0
beq 12f
bset IMM (31),d1
12: lsrl IMM (1),d0
addl IMM (1),d4
#endif
1:
lea Lsubdf$1,a0 | to return from rounding routine
lea SYM (_fpCCR),a1 | check the rounding mode
#ifdef __mcf5200__
clrl d6
#endif
movew a1@(6),d6 | rounding mode in d6
beq Lround$to$nearest
#ifndef __mcf5200__
cmpw IMM (ROUND_TO_PLUS),d6
#else
cmpl IMM (ROUND_TO_PLUS),d6
#endif
bhi Lround$to$minus
blt Lround$to$zero
bra Lround$to$plus
Lsubdf$1:
| Put back the exponent and sign (we don't have overflow). '
bclr IMM (DBL_MANT_DIG-1),d0
#ifndef __mcf5200__
lslw IMM (4),d4 | put exponent back into position
#else
lsll IMM (4),d4 | put exponent back into position
#endif
swap d0 |
#ifndef __mcf5200__
orw d4,d0 |
#else
orl d4,d0 |
#endif
swap d0 |
bra Ladddf$ret
......@@ -825,7 +1130,11 @@ Lsubdf$1:
| DBL_MANT_DIG+1) we return the other (and now we don't have to '
| check for finiteness or zero).
Ladddf$a$small:
#ifndef __mcf5200__
moveml sp@+,a2-a3
#else
moveml sp@+,a2-a4
#endif
movel a6@(16),d0
movel a6@(20),d1
lea SYM (_fpCCR),a0
......@@ -835,7 +1144,11 @@ Ladddf$a$small:
rts
Ladddf$b$small:
#ifndef __mcf5200__
moveml sp@+,a2-a3
#else
moveml sp@+,a2-a4
#endif
movel a6@(8),d0
movel a6@(12),d1
lea SYM (_fpCCR),a0
......@@ -893,8 +1206,16 @@ Ladddf$ret:
Ladddf$ret$den:
| Return a denormalized number.
#ifndef __mcf5200__
lsrl IMM (1),d0 | shift right once more
roxrl IMM (1),d1 |
#else
lsrl IMM (1),d1
btst IMM (0),d0
beq 10f
bset IMM (31),d1
10: lsrl IMM (1),d0
#endif
bra Ladddf$ret
Ladddf$nf:
......@@ -987,17 +1308,30 @@ SYM (__muldf3):
andl d6,d0 | isolate fraction
orl IMM (0x00100000),d0 | and put hidden bit back
swap d4 | I like exponents in the first byte
#ifndef __mcf5200__
lsrw IMM (4),d4 |
#else
lsrl IMM (4),d4 |
#endif
Lmuldf$1:
andl d7,d5 |
beq Lmuldf$b$den |
andl d6,d2 |
orl IMM (0x00100000),d2 | and put hidden bit back
swap d5 |
#ifndef __mcf5200__
lsrw IMM (4),d5 |
#else
lsrl IMM (4),d5 |
#endif
Lmuldf$2: |
#ifndef __mcf5200__
addw d5,d4 | add exponents
subw IMM (D_BIAS+1),d4 | and subtract bias (plus one)
#else
addl d5,d4 | add exponents
subl IMM (D_BIAS+1),d4 | and subtract bias (plus one)
#endif
| We are now ready to do the multiplication. The situation is as follows:
| both a and b have bit 52 ( bit 20 of d0 and d2) set (even if they were
......@@ -1009,11 +1343,16 @@ Lmuldf$2: |
| enough to keep everything in them. So we use the address registers to keep
| some intermediate data.
#ifndef __mcf5200__
moveml a2-a3,sp@- | save a2 and a3 for temporary use
#else
moveml a2-a4,sp@-
#endif
movel IMM (0),a2 | a2 is a null register
movel d4,a3 | and a3 will preserve the exponent
| First, shift d2-d3 so bit 20 becomes bit 31:
#ifndef __mcf5200__
rorl IMM (5),d2 | rotate d2 5 places right
swap d2 | and swap it
rorl IMM (5),d3 | do the same thing with d3
......@@ -1022,6 +1361,16 @@ Lmuldf$2: |
andw IMM (0x07ff),d6 |
orw d6,d2 | and put them into d2
andw IMM (0xf800),d3 | clear those bits in d3
#else
moveq IMM (11),d7 | left shift d2 11 bits
lsll d7,d2
movel d3,d6 | get a copy of d3
lsll d7,d3 | left shift d3 11 bits
andl IMM (0xffe00000),d6 | get the top 11 bits of d3
moveq IMM (21),d7 | right shift them 21 bits
lsrl d7,d6
orl d6,d2 | stick them at the end of d2
#endif
movel d2,d6 | move b into d6-d7
movel d3,d7 | move a into d4-d5
......@@ -1034,9 +1383,22 @@ Lmuldf$2: |
| We use a1 as counter:
movel IMM (DBL_MANT_DIG-1),a1
#ifndef __mcf5200__
exg d7,a1
#else
movel d7,a4
movel a1,d7
movel a4,a1
#endif
1: exg d7,a1 | put counter back in a1
1:
#ifndef __mcf5200__
exg d7,a1 | put counter back in a1
#else
movel d7,a4
movel a1,d7
movel a4,a1
#endif
addl d3,d3 | shift sum once left
addxl d2,d2 |
addxl d1,d1 |
......@@ -1044,17 +1406,42 @@ Lmuldf$2: |
addl d7,d7 |
addxl d6,d6 |
bcc 2f | if bit clear skip the following
#ifndef __mcf5200__
exg d7,a2 |
#else
movel d7,a4
movel a2,d7
movel a4,a2
#endif
addl d5,d3 | else add a to the sum
addxl d4,d2 |
addxl d7,d1 |
addxl d7,d0 |
#ifndef __mcf5200__
exg d7,a2 |
2: exg d7,a1 | put counter in d7
#else
movel d7,a4
movel a2,d7
movel a4,a2
#endif
2:
#ifndef __mcf5200__
exg d7,a1 | put counter in d7
dbf d7,1b | decrement and branch
#else
movel d7,a4
movel a1,d7
movel a4,a1
subql IMM (1),d7
bpl 1b
#endif
movel a3,d4 | restore exponent
#ifndef __mcf5200__
moveml sp@+,a2-a3
#else
moveml sp@+,a2-a4
#endif
| Now we have the product in d0-d1-d2-d3, with bit 8 of d0 set. The
| first thing to do now is to normalize it so bit 8 becomes bit
......@@ -1067,6 +1454,7 @@ Lmuldf$2: |
swap d3
movew d3,d2
movew IMM (0),d3
#ifndef __mcf5200__
lsrl IMM (1),d0
roxrl IMM (1),d1
roxrl IMM (1),d2
......@@ -1079,6 +1467,22 @@ Lmuldf$2: |
roxrl IMM (1),d1
roxrl IMM (1),d2
roxrl IMM (1),d3
#else
moveq IMM (29),d6
lsrl IMM (3),d3
movel d2,d7
lsll d6,d7
orl d7,d3
lsrl IMM (3),d2
movel d1,d7
lsll d6,d7
orl d7,d2
lsrl IMM (3),d1
movel d0,d7
lsll d6,d7
orl d7,d1
lsrl IMM (3),d0
#endif
| Now round, check for over- and underflow, and exit.
movel a0,d7 | get sign bit back into d7
......@@ -1086,9 +1490,18 @@ Lmuldf$2: |
btst IMM (DBL_MANT_DIG+1-32),d0
beq Lround$exit
#ifndef __mcf5200__
lsrl IMM (1),d0
roxrl IMM (1),d1
addw IMM (1),d4
#else
lsrl IMM (1),d1
btst IMM (0),d0
beq 10f
bset IMM (31),d1
10: lsrl IMM (1),d0
addl IMM (1),d4
#endif
bra Lround$exit
Lmuldf$inop:
......@@ -1113,8 +1526,17 @@ Lmuldf$a$nf:
| NaN, in which case we return NaN.
Lmuldf$b$0:
movew IMM (MULTIPLY),d5
#ifndef __mcf5200__
exg d2,d0 | put b (==0) into d0-d1
exg d3,d1 | and a (with sign bit cleared) into d2-d3
#else
movel d2,d7
movel d0,d2
movel d7,d0
movel d3,d7
movel d1,d3
movel d7,d1
#endif
bra 1f
Lmuldf$a$0:
movel a6@(16),d2 | put b into d2-d3 again
......@@ -1137,7 +1559,11 @@ Lmuldf$a$den:
andl d6,d0
1: addl d1,d1 | shift a left until bit 20 is set
addxl d0,d0 |
#ifndef __mcf5200__
subw IMM (1),d4 | and adjust exponent
#else
subl IMM (1),d4 | and adjust exponent
#endif
btst IMM (20),d0 |
bne Lmuldf$1 |
bra 1b
......@@ -1147,7 +1573,11 @@ Lmuldf$b$den:
andl d6,d2
1: addl d3,d3 | shift b left until bit 20 is set
addxl d2,d2 |
#ifndef __mcf5200__
subw IMM (1),d5 | and adjust exponent
#else
subql IMM (1),d5 | and adjust exponent
#endif
btst IMM (20),d2 |
bne Lmuldf$2 |
bra 1b
......@@ -1199,17 +1629,30 @@ SYM (__divdf3):
andl d6,d0 | and isolate fraction
orl IMM (0x00100000),d0 | and put hidden bit back
swap d4 | I like exponents in the first byte
#ifndef __mcf5200__
lsrw IMM (4),d4 |
#else
lsrl IMM (4),d4 |
#endif
Ldivdf$1: |
andl d7,d5 |
beq Ldivdf$b$den |
andl d6,d2 |
orl IMM (0x00100000),d2
swap d5 |
#ifndef __mcf5200__
lsrw IMM (4),d5 |
#else
lsrl IMM (4),d5 |
#endif
Ldivdf$2: |
#ifndef __mcf5200__
subw d5,d4 | subtract exponents
addw IMM (D_BIAS),d4 | and add bias
#else
subl d5,d4 | subtract exponents
addl IMM (D_BIAS),d4 | and add bias
#endif
| We are now ready to do the division. We have prepared things in such a way
| that the ratio of the fractions will be less than 2 but greater than 1/2.
......@@ -1240,7 +1683,12 @@ Ldivdf$2: |
bset d5,d6 | set the corresponding bit in d6
3: addl d1,d1 | shift a by 1
addxl d0,d0 |
#ifndef __mcf5200__
dbra d5,1b | and branch back
#else
subql IMM (1), d5
bpl 1b
#endif
bra 5f
4: cmpl d1,d3 | here d0==d2, so check d1 and d3
bhi 3b | if d1 > d2 skip the subtraction
......@@ -1257,7 +1705,12 @@ Ldivdf$2: |
bset d5,d7 | set the corresponding bit in d7
3: addl d1,d1 | shift a by 1
addxl d0,d0 |
#ifndef __mcf5200__
dbra d5,1b | and branch back
#else
subql IMM (1), d5
bpl 1b
#endif
bra 5f
4: cmpl d1,d3 | here d0==d2, so check d1 and d3
bhi 3b | if d1 > d2 skip the subtraction
......@@ -1270,7 +1723,12 @@ Ldivdf$2: |
beq 3f | if d0==d2 check d1 and d3
2: addl d1,d1 | shift a by 1
addxl d0,d0 |
#ifndef __mcf5200__
dbra d5,1b | and branch back
#else
subql IMM (1), d5
bpl 1b
#endif
movel IMM (0),d2 | here no sticky bit was found
movel d2,d3
bra 5f
......@@ -1281,13 +1739,23 @@ Ldivdf$2: |
| to it; if you don't do this the algorithm loses in some cases). '
movel IMM (0),d2
movel d2,d3
#ifndef __mcf5200__
subw IMM (DBL_MANT_DIG),d5
addw IMM (63),d5
cmpw IMM (31),d5
#else
subl IMM (DBL_MANT_DIG),d5
addl IMM (63),d5
cmpl IMM (31),d5
#endif
bhi 2f
1: bset d5,d3
bra 5f
#ifndef __mcf5200__
subw IMM (32),d5
#else
subl IMM (32),d5
#endif
2: bset d5,d2
5:
| Finally we are finished! Move the longs in the address registers to
......@@ -1302,11 +1770,28 @@ Ldivdf$2: |
| not set:
btst IMM (DBL_MANT_DIG-32+1),d0
beq 1f
#ifndef __mcf5200__
lsrl IMM (1),d0
roxrl IMM (1),d1
roxrl IMM (1),d2
roxrl IMM (1),d3
addw IMM (1),d4
#else
lsrl IMM (1),d3
btst IMM (0),d2
beq 10f
bset IMM (31),d3
10: lsrl IMM (1),d2
btst IMM (0),d1
beq 11f
bset IMM (31),d2
11: lsrl IMM (1),d1
btst IMM (0),d0
beq 12f
bset IMM (31),d1
12: lsrl IMM (1),d0
addl IMM (1),d4
#endif
1:
| Now round, check for over- and underflow, and exit.
movel a0,d7 | restore sign bit to d7
......@@ -1377,7 +1862,11 @@ Ldivdf$a$den:
andl d6,d0
1: addl d1,d1 | shift a left until bit 20 is set
addxl d0,d0
#ifndef __mcf5200__
subw IMM (1),d4 | and adjust exponent
#else
subl IMM (1),d4 | and adjust exponent
#endif
btst IMM (DBL_MANT_DIG-32-1),d0
bne Ldivdf$1
bra 1b
......@@ -1387,7 +1876,11 @@ Ldivdf$b$den:
andl d6,d2
1: addl d3,d3 | shift b left until bit 20 is set
addxl d2,d2
#ifndef __mcf5200__
subw IMM (1),d5 | and adjust exponent
#else
subql IMM (1),d5 | and adjust exponent
#endif
btst IMM (DBL_MANT_DIG-32-1),d2
bne Ldivdf$2
bra 1b
......@@ -1398,7 +1891,11 @@ Lround$exit:
| so that 2^21 <= d0 < 2^22, and the exponent is in the lower byte of d4.
| First check for underlow in the exponent:
#ifndef __mcf5200__
cmpw IMM (-DBL_MANT_DIG-1),d4
#else
cmpl IMM (-DBL_MANT_DIG-1),d4
#endif
blt Ld$underflow
| It could happen that the exponent is less than 1, in which case the
| number is denormalized. In this case we shift right and adjust the
......@@ -1407,9 +1904,15 @@ Lround$exit:
movel d7,a0 |
movel IMM (0),d6 | use d6-d7 to collect bits flushed right
movel d6,d7 | use d6-d7 to collect bits flushed right
#ifndef __mcf5200__
cmpw IMM (1),d4 | if the exponent is less than 1 we
#else
cmpl IMM (1),d4 | if the exponent is less than 1 we
#endif
bge 2f | have to shift right (denormalize)
1: addw IMM (1),d4 | adjust the exponent
1:
#ifndef __mcf5200__
addw IMM (1),d4 | adjust the exponent
lsrl IMM (1),d0 | shift right once
roxrl IMM (1),d1 |
roxrl IMM (1),d2 |
......@@ -1417,6 +1920,31 @@ Lround$exit:
roxrl IMM (1),d6 |
roxrl IMM (1),d7 |
cmpw IMM (1),d4 | is the exponent 1 already?
#else
addl IMM (1),d4 | adjust the exponent
lsrl IMM (1),d7
btst IMM (0),d6
beq 13f
bset IMM (31),d7
13: lsrl IMM (1),d6
btst IMM (0),d3
beq 14f
bset IMM (31),d6
14: lsrl IMM (1),d3
btst IMM (0),d2
beq 10f
bset IMM (31),d3
10: lsrl IMM (1),d2
btst IMM (0),d1
beq 11f
bset IMM (31),d2
11: lsrl IMM (1),d1
btst IMM (0),d0
beq 12f
bset IMM (31),d1
12: lsrl IMM (1),d0
cmpl IMM (1),d4 | is the exponent 1 already?
#endif
beq 2f | if not loop back
bra 1b |
bra Ld$underflow | safety check, shouldn't execute '
......@@ -1426,9 +1954,16 @@ Lround$exit:
| Now call the rounding routine (which takes care of denormalized numbers):
lea Lround$0,a0 | to return from rounding routine
lea SYM (_fpCCR),a1 | check the rounding mode
#ifdef __mcf5200__
clrl d6
#endif
movew a1@(6),d6 | rounding mode in d6
beq Lround$to$nearest
#ifndef __mcf5200__
cmpw IMM (ROUND_TO_PLUS),d6
#else
cmpl IMM (ROUND_TO_PLUS),d6
#endif
bhi Lround$to$minus
blt Lround$to$zero
bra Lround$to$plus
......@@ -1440,17 +1975,29 @@ Lround$0:
| check again for underflow!). We have to check for overflow or for a
| denormalized number (which also signals underflow).
| Check for overflow (i.e., exponent >= 0x7ff).
#ifndef __mcf5200__
cmpw IMM (0x07ff),d4
#else
cmpl IMM (0x07ff),d4
#endif
bge Ld$overflow
| Now check for a denormalized number (exponent==0):
movew d4,d4
beq Ld$den
1:
| Put back the exponents and sign and return.
#ifndef __mcf5200__
lslw IMM (4),d4 | exponent back to fourth byte
#else
lsll IMM (4),d4 | exponent back to fourth byte
#endif
bclr IMM (DBL_MANT_DIG-32-1),d0
swap d0 | and put back exponent
#ifndef __mcf5200__
orw d4,d0 |
#else
orl d4,d0 |
#endif
swap d0 |
orl d7,d0 | and sign also
......@@ -1542,8 +2089,17 @@ Lcmpdf$1:
tstl d6
bpl 1f
| If both are negative exchange them
#ifndef __mcf5200__
exg d0,d2
exg d1,d3
#else
movel d0,d7
movel d2,d0
movel d7,d2
movel d1,d7
movel d3,d1
movel d7,d3
#endif
1:
| Now that they are positive we just compare them as longs (does this also
| work for denormalized numbers?).
......@@ -1608,13 +2164,22 @@ Lround$to$nearest:
| Normalize shifting left until bit #DBL_MANT_DIG-32 is set or the exponent
| is one (remember that a denormalized number corresponds to an
| exponent of -D_BIAS+1).
#ifndef __mcf5200__
cmpw IMM (1),d4 | remember that the exponent is at least one
#else
cmpl IMM (1),d4 | remember that the exponent is at least one
#endif
beq 2f | an exponent of one means denormalized
addl d3,d3 | else shift and adjust the exponent
addxl d2,d2 |
addxl d1,d1 |
addxl d0,d0 |
#ifndef __mcf5200__
dbra d4,1b |
#else
subql IMM (1), d4
bpl 1b
#endif
2:
| Now round: we do it as follows: after the shifting we can write the
| fraction part as f + delta, where 1 < f < 2^25, and 0 <= delta <= 2.
......@@ -1636,16 +2201,34 @@ Lround$to$nearest:
addl d3,d1 |
addxl d2,d0
| Shift right once (because we used bit #DBL_MANT_DIG-32!).
2: lsrl IMM (1),d0
2:
#ifndef __mcf5200__
lsrl IMM (1),d0
roxrl IMM (1),d1
#else
lsrl IMM (1),d1
btst IMM (0),d0
beq 10f
bset IMM (31),d1
10: lsrl IMM (1),d0
#endif
| Now check again bit #DBL_MANT_DIG-32 (rounding could have produced a
| 'fraction overflow' ...).
btst IMM (DBL_MANT_DIG-32),d0
beq 1f
#ifndef __mcf5200__
lsrl IMM (1),d0
roxrl IMM (1),d1
addw IMM (1),d4
#else
lsrl IMM (1),d1
btst IMM (0),d0
beq 10f
bset IMM (31),d1
10: lsrl IMM (1),d0
addl IMM (1),d4
#endif
1:
| If bit #DBL_MANT_DIG-32-1 is clear we have a denormalized number, so we
| have to put the exponent to zero and return a denormalized number.
......@@ -1717,7 +2300,7 @@ Lf$den:
| Return and signal a denormalized number
orl d7,d0
movew IMM (INEXACT_RESULT+UNDERFLOW),d7
movew IMM (SINGLE_FLOAT),d6
moveq IMM (SINGLE_FLOAT),d6
jmp $_exception_handler
Lf$infty:
......@@ -1726,21 +2309,21 @@ Lf$overflow:
movel IMM (INFINITY),d0
orl d7,d0
movew IMM (INEXACT_RESULT+OVERFLOW),d7
movew IMM (SINGLE_FLOAT),d6
moveq IMM (SINGLE_FLOAT),d6
jmp $_exception_handler
Lf$underflow:
| Return 0 and set the exception flags
movel IMM (0),d0
movew IMM (INEXACT_RESULT+UNDERFLOW),d7
movew IMM (SINGLE_FLOAT),d6
moveq IMM (SINGLE_FLOAT),d6
jmp $_exception_handler
Lf$inop:
| Return a quiet NaN and set the exception flags
movel IMM (QUIET_NaN),d0
movew IMM (INEXACT_RESULT+INVALID_OPERATION),d7
movew IMM (SINGLE_FLOAT),d6
moveq IMM (SINGLE_FLOAT),d6
jmp $_exception_handler
Lf$div$0:
......@@ -1748,7 +2331,7 @@ Lf$div$0:
movel IMM (INFINITY),d0
orl d7,d0
movew IMM (INEXACT_RESULT+DIVIDE_BY_ZERO),d7
movew IMM (SINGLE_FLOAT),d6
moveq IMM (SINGLE_FLOAT),d6
jmp $_exception_handler
|=============================================================================
......@@ -1840,54 +2423,126 @@ Laddsf$2:
| same, and put the largest exponent in d6. Note that we are using two
| registers for each number (see the discussion by D. Knuth in "Seminumerical
| Algorithms").
#ifndef __mcf5200__
cmpw d6,d7 | compare exponents
#else
cmpl d6,d7 | compare exponents
#endif
beq Laddsf$3 | if equal don't shift '
bhi 5f | branch if second exponent largest
1:
subl d6,d7 | keep the largest exponent
negl d7
#ifndef __mcf5200__
lsrw IMM (8),d7 | put difference in lower byte
#else
lsrl IMM (8),d7 | put difference in lower byte
#endif
| if difference is too large we don't shift (actually, we can just exit) '
#ifndef __mcf5200__
cmpw IMM (FLT_MANT_DIG+2),d7
#else
cmpl IMM (FLT_MANT_DIG+2),d7
#endif
bge Laddsf$b$small
#ifndef __mcf5200__
cmpw IMM (16),d7 | if difference >= 16 swap
#else
cmpl IMM (16),d7 | if difference >= 16 swap
#endif
bge 4f
2:
#ifndef __mcf5200__
subw IMM (1),d7
3: lsrl IMM (1),d2 | shift right second operand
#else
subql IMM (1), d7
#endif
3:
#ifndef __mcf5200__
lsrl IMM (1),d2 | shift right second operand
roxrl IMM (1),d3
dbra d7,3b
#else
lsrl IMM (1),d3
btst IMM (0),d2
beq 10f
bset IMM (31),d3
10: lsrl IMM (1),d2
subql IMM (1), d7
bpl 3b
#endif
bra Laddsf$3
4:
movew d2,d3
swap d3
movew d3,d2
swap d2
#ifndef __mcf5200__
subw IMM (16),d7
#else
subl IMM (16),d7
#endif
bne 2b | if still more bits, go back to normal case
bra Laddsf$3
5:
#ifndef __mcf5200__
exg d6,d7 | exchange the exponents
#else
eorl d6,d7
eorl d7,d6
eorl d6,d7
#endif
subl d6,d7 | keep the largest exponent
negl d7 |
#ifndef __mcf5200__
lsrw IMM (8),d7 | put difference in lower byte
#else
lsrl IMM (8),d7 | put difference in lower byte
#endif
| if difference is too large we don't shift (and exit!) '
#ifndef __mcf5200__
cmpw IMM (FLT_MANT_DIG+2),d7
#else
cmpl IMM (FLT_MANT_DIG+2),d7
#endif
bge Laddsf$a$small
#ifndef __mcf5200__
cmpw IMM (16),d7 | if difference >= 16 swap
#else
cmpl IMM (16),d7 | if difference >= 16 swap
#endif
bge 8f
6:
#ifndef __mcf5200__
subw IMM (1),d7
7: lsrl IMM (1),d0 | shift right first operand
#else
subl IMM (1),d7
#endif
7:
#ifndef __mcf5200__
lsrl IMM (1),d0 | shift right first operand
roxrl IMM (1),d1
dbra d7,7b
#else
lsrl IMM (1),d1
btst IMM (0),d0
beq 10f
bset IMM (31),d1
10: lsrl IMM (1),d0
subql IMM (1),d7
bpl 7b
#endif
bra Laddsf$3
8:
movew d0,d1
swap d1
movew d1,d0
swap d0
#ifndef __mcf5200__
subw IMM (16),d7
#else
subl IMM (16),d7
#endif
bne 6b | if still more bits, go back to normal case
| otherwise we fall through
......@@ -1896,15 +2551,30 @@ Laddsf$2:
Laddsf$3:
| Here we have to decide whether to add or subtract the numbers
#ifndef __mcf5200__
exg d6,a0 | get signs back
exg d7,a1 | and save the exponents
#else
movel d6,d4
movel a0,d6
movel d4,d6
movel d7,d4
movel a1,d4
movel d4,a1
#endif
eorl d6,d7 | combine sign bits
bmi Lsubsf$0 | if negative a and b have opposite
| sign so we actually subtract the
| numbers
| Here we have both positive or both negative
#ifndef __mcf5200__
exg d6,a0 | now we have the exponent in d6
#else
movel d6,d4
movel a0,d6
movel d4,a0
#endif
movel a0,d7 | and sign in d7
andl IMM (0x80000000),d7
| Here we do the addition.
......@@ -1915,7 +2585,11 @@ Laddsf$3:
| Put the exponent, in the first byte, in d2, to use the "standard" rounding
| routines:
movel d6,d2
#ifndef __mcf5200__
lsrw IMM (8),d2
#else
lsrl IMM (8),d2
#endif
| Before rounding normalize so bit #FLT_MANT_DIG is set (we will consider
| the case of denormalized numbers in the rounding routine itself).
......@@ -1923,24 +2597,47 @@ Laddsf$3:
| one more bit we check this:
btst IMM (FLT_MANT_DIG+1),d0
beq 1f
#ifndef __mcf5200__
lsrl IMM (1),d0
roxrl IMM (1),d1
#else
lsrl IMM (1),d1
btst IMM (0),d0
beq 10f
bset IMM (31),d1
10: lsrl IMM (1),d0
#endif
addl IMM (1),d2
1:
lea Laddsf$4,a0 | to return from rounding routine
lea SYM (_fpCCR),a1 | check the rounding mode
#ifdef __mcf5200__
clrl d6
#endif
movew a1@(6),d6 | rounding mode in d6
beq Lround$to$nearest
#ifndef __mcf5200__
cmpw IMM (ROUND_TO_PLUS),d6
#else
cmpl IMM (ROUND_TO_PLUS),d6
#endif
bhi Lround$to$minus
blt Lround$to$zero
bra Lround$to$plus
Laddsf$4:
| Put back the exponent, but check for overflow.
#ifndef __mcf5200__
cmpw IMM (0xff),d2
#else
cmpl IMM (0xff),d2
#endif
bhi 1f
bclr IMM (FLT_MANT_DIG-1),d0
#ifndef __mcf5200__
lslw IMM (7),d2
#else
lsll IMM (7),d2
#endif
swap d2
orl d2,d0
bra Laddsf$ret
......@@ -1962,8 +2659,15 @@ Lsubsf$0:
negl d1
negxl d0
1:
#ifndef __mcf5200__
exg d2,a0 | now we have the exponent in d2
lsrw IMM (8),d2 | put it in the first byte
#else
movel d2,d4
movel a0,d2
movel d4,a0
lsrl IMM (8),d2 | put it in the first byte
#endif
| Now d0-d1 is positive and the sign bit is in d7.
......@@ -1972,16 +2676,27 @@ Lsubsf$0:
| the rounding routines themselves.
lea Lsubsf$1,a0 | to return from rounding routine
lea SYM (_fpCCR),a1 | check the rounding mode
#ifdef __mcf5200__
clrl d6
#endif
movew a1@(6),d6 | rounding mode in d6
beq Lround$to$nearest
#ifndef __mcf5200__
cmpw IMM (ROUND_TO_PLUS),d6
#else
cmpl IMM (ROUND_TO_PLUS),d6
#endif
bhi Lround$to$minus
blt Lround$to$zero
bra Lround$to$plus
Lsubsf$1:
| Put back the exponent (we can't have overflow!). '
bclr IMM (FLT_MANT_DIG-1),d0
#ifndef __mcf5200__
lslw IMM (7),d2
#else
lsll IMM (7),d2
#endif
swap d2
orl d2,d0
bra Laddsf$ret
......@@ -2144,17 +2859,30 @@ SYM (__mulsf3):
andl d5,d0 | and isolate fraction
orl d4,d0 | and put hidden bit back
swap d2 | I like exponents in the first byte
#ifndef __mcf5200__
lsrw IMM (7),d2 |
#else
lsrl IMM (7),d2 |
#endif
Lmulsf$1: | number
andl d6,d3 |
beq Lmulsf$b$den |
andl d5,d1 |
orl d4,d1 |
swap d3 |
#ifndef __mcf5200__
lsrw IMM (7),d3 |
#else
lsrl IMM (7),d3 |
#endif
Lmulsf$2: |
#ifndef __mcf5200__
addw d3,d2 | add exponents
subw IMM (F_BIAS+1),d2 | and subtract bias (plus one)
#else
addl d3,d2 | add exponents
subl IMM (F_BIAS+1),d2 | and subtract bias (plus one)
#endif
| We are now ready to do the multiplication. The situation is as follows:
| both a and b have bit FLT_MANT_DIG-1 set (even if they were
......@@ -2180,28 +2908,58 @@ Lmulsf$2: |
bcc 2f | if not set skip sum
addl d5,d1 | add a
addxl d4,d0
2: dbf d3,1b | loop back
2:
#ifndef __mcf5200__
dbf d3,1b | loop back
#else
subql IMM (1),d3
bpl 1b
#endif
| Now we have the product in d0-d1, with bit (FLT_MANT_DIG - 1) + FLT_MANT_DIG
| (mod 32) of d0 set. The first thing to do now is to normalize it so bit
| FLT_MANT_DIG is set (to do the rounding).
#ifndef __mcf5200__
rorl IMM (6),d1
swap d1
movew d1,d3
andw IMM (0x03ff),d3
andw IMM (0xfd00),d1
#else
movel d1,d3
lsll IMM (8),d1
addl d1,d1
addl d1,d1
moveq IMM (22),d5
lsrl d5,d3
orl d3,d1
andl IMM (0xfffffd00),d1
#endif
lsll IMM (8),d0
addl d0,d0
addl d0,d0
#ifndef __mcf5200__
orw d3,d0
#else
orl d3,d0
#endif
movew IMM (MULTIPLY),d5
btst IMM (FLT_MANT_DIG+1),d0
beq Lround$exit
#ifndef __mcf5200__
lsrl IMM (1),d0
roxrl IMM (1),d1
addw IMM (1),d2
#else
lsrl IMM (1),d1
btst IMM (0),d0
beq 10f
bset IMM (31),d1
10: lsrl IMM (1),d0
addql IMM (1),d2
#endif
bra Lround$exit
Lmulsf$inop:
......@@ -2246,7 +3004,11 @@ Lmulsf$a$den:
movel IMM (1),d2
andl d5,d0
1: addl d0,d0 | shift a left (until bit 23 is set)
#ifndef __mcf5200__
subw IMM (1),d2 | and adjust exponent
#else
subql IMM (1),d2 | and adjust exponent
#endif
btst IMM (FLT_MANT_DIG-1),d0
bne Lmulsf$1 |
bra 1b | else loop back
......@@ -2255,7 +3017,11 @@ Lmulsf$b$den:
movel IMM (1),d3
andl d5,d1
1: addl d1,d1 | shift b left until bit 23 is set
#ifndef __mcf5200__
subw IMM (1),d3 | and adjust exponent
#else
subl IMM (1),d3 | and adjust exponent
#endif
btst IMM (FLT_MANT_DIG-1),d1
bne Lmulsf$2 |
bra 1b | else loop back
......@@ -2298,17 +3064,30 @@ SYM (__divsf3):
andl d5,d0 | and isolate fraction
orl d4,d0 | and put hidden bit back
swap d2 | I like exponents in the first byte
#ifndef __mcf5200__
lsrw IMM (7),d2 |
#else
lsrl IMM (7),d2 |
#endif
Ldivsf$1: |
andl d6,d3 |
beq Ldivsf$b$den |
andl d5,d1 |
orl d4,d1 |
swap d3 |
#ifndef __mcf5200__
lsrw IMM (7),d3 |
#else
lsrl IMM (7),d3 |
#endif
Ldivsf$2: |
#ifndef __mcf5200__
subw d3,d2 | subtract exponents
addw IMM (F_BIAS),d2 | and add bias
#else
subl d3,d2 | subtract exponents
addl IMM (F_BIAS),d2 | and add bias
#endif
| We are now ready to do the division. We have prepared things in such a way
| that the ratio of the fractions will be less than 2 but greater than 1/2.
......@@ -2329,19 +3108,34 @@ Ldivsf$2: |
subl d1,d0 | if a >= b a <-- a-b
beq 3f | if a is zero, exit
2: addl d0,d0 | multiply a by 2
#ifndef __mcf5200__
dbra d3,1b
#else
subql IMM (1),d3
bpl 1b
#endif
| Now we keep going to set the sticky bit ...
movew IMM (FLT_MANT_DIG),d3
1: cmpl d0,d1
ble 2f
addl d0,d0
#ifndef __mcf5200__
dbra d3,1b
#else
subql IMM(1),d3
bpl 1b
#endif
movel IMM (0),d1
bra 3f
2: movel IMM (0),d1
#ifndef __mcf5200__
subw IMM (FLT_MANT_DIG),d3
addw IMM (31),d3
#else
subl IMM (FLT_MANT_DIG),d3
addl IMM (31),d3
#endif
bset d3,d1
3:
movel d6,d0 | put the ratio in d0-d1
......@@ -2353,7 +3147,11 @@ Ldivsf$2: |
btst IMM (FLT_MANT_DIG+1),d0
beq 1f | if it is not set, then bit 24 is set
lsrl IMM (1),d0 |
#ifndef __mcf5200__
addw IMM (1),d2 |
#else
addl IMM (1),d2 |
#endif
1:
| Now round, check for over- and underflow, and exit.
movew IMM (DIVIDE),d5
......@@ -2409,7 +3207,11 @@ Ldivsf$a$den:
movel IMM (1),d2
andl d5,d0
1: addl d0,d0 | shift a left until bit FLT_MANT_DIG-1 is set
#ifndef __mcf5200__
subw IMM (1),d2 | and adjust exponent
#else
subl IMM (1),d2 | and adjust exponent
#endif
btst IMM (FLT_MANT_DIG-1),d0
bne Ldivsf$1
bra 1b
......@@ -2418,7 +3220,11 @@ Ldivsf$b$den:
movel IMM (1),d3
andl d5,d1
1: addl d1,d1 | shift b left until bit FLT_MANT_DIG is set
#ifndef __mcf5200__
subw IMM (1),d3 | and adjust exponent
#else
subl IMM (1),d3 | and adjust exponent
#endif
btst IMM (FLT_MANT_DIG-1),d1
bne Ldivsf$2
bra 1b
......@@ -2427,20 +3233,43 @@ Lround$exit:
| This is a common exit point for __mulsf3 and __divsf3.
| First check for underlow in the exponent:
#ifndef __mcf5200__
cmpw IMM (-FLT_MANT_DIG-1),d2
#else
cmpl IMM (-FLT_MANT_DIG-1),d2
#endif
blt Lf$underflow
| It could happen that the exponent is less than 1, in which case the
| number is denormalized. In this case we shift right and adjust the
| exponent until it becomes 1 or the fraction is zero (in the latter case
| we signal underflow and return zero).
movel IMM (0),d6 | d6 is used temporarily
#ifndef __mcf5200__
cmpw IMM (1),d2 | if the exponent is less than 1 we
#else
cmpl IMM (1),d2 | if the exponent is less than 1 we
#endif
bge 2f | have to shift right (denormalize)
1: addw IMM (1),d2 | adjust the exponent
1:
#ifndef __mcf5200__
addw IMM (1),d2 | adjust the exponent
lsrl IMM (1),d0 | shift right once
roxrl IMM (1),d1 |
roxrl IMM (1),d6 | d6 collect bits we would lose otherwise
cmpw IMM (1),d2 | is the exponent 1 already?
#else
addql IMM (1),d2 | adjust the exponent
lsrl IMM (1),d6
btst IMM (0),d1
beq 11f
bset IMM (31),d6
11: lsrl IMM (1),d1
btst IMM (0),d0
beq 10f
bset IMM (31),d1
10: lsrl IMM (1),d0
cmpl IMM (1),d2 | is the exponent 1 already?
#endif
beq 2f | if not loop back
bra 1b |
bra Lf$underflow | safety check, shouldn't execute '
......@@ -2449,9 +3278,16 @@ Lround$exit:
| Now call the rounding routine (which takes care of denormalized numbers):
lea Lround$0,a0 | to return from rounding routine
lea SYM (_fpCCR),a1 | check the rounding mode
#ifdef __mcf5200__
clrl d6
#endif
movew a1@(6),d6 | rounding mode in d6
beq Lround$to$nearest
#ifndef __mcf5200__
cmpw IMM (ROUND_TO_PLUS),d6
#else
cmpl IMM (ROUND_TO_PLUS),d6
#endif
bhi Lround$to$minus
blt Lround$to$zero
bra Lround$to$plus
......@@ -2463,17 +3299,29 @@ Lround$0:
| check again for underflow!). We have to check for overflow or for a
| denormalized number (which also signals underflow).
| Check for overflow (i.e., exponent >= 255).
#ifndef __mcf5200__
cmpw IMM (0x00ff),d2
#else
cmpl IMM (0x00ff),d2
#endif
bge Lf$overflow
| Now check for a denormalized number (exponent==0).
movew d2,d2
beq Lf$den
1:
| Put back the exponents and sign and return.
#ifndef __mcf5200__
lslw IMM (7),d2 | exponent back to fourth byte
#else
lsll IMM (7),d2 | exponent back to fourth byte
#endif
bclr IMM (FLT_MANT_DIG-1),d0
swap d0 | and put back exponent
#ifndef __mcf5200__
orw d2,d0 |
#else
orl d2,d0
#endif
swap d0 |
orl d7,d0 | and sign also
......@@ -2557,7 +3405,13 @@ Lcmpsf$2:
tstl d6
bpl 1f
| If both are negative exchange them
#ifndef __mcf5200__
exg d0,d1
#else
movel d0,d7
movel d1,d0
movel d7,d1
#endif
1:
| Now that they are positive we just compare them as longs (does this also
| work for denormalized numbers?).
......@@ -2608,11 +3462,20 @@ Lround$to$nearest:
| Normalize shifting left until bit #FLT_MANT_DIG is set or the exponent
| is one (remember that a denormalized number corresponds to an
| exponent of -F_BIAS+1).
#ifndef __mcf5200__
cmpw IMM (1),d2 | remember that the exponent is at least one
#else
cmpl IMM (1),d2 | remember that the exponent is at least one
#endif
beq 2f | an exponent of one means denormalized
addl d1,d1 | else shift and adjust the exponent
addxl d0,d0 |
#ifndef __mcf5200__
dbra d2,1b |
#else
subql IMM (1),d2
bpl 1b
#endif
2:
| Now round: we do it as follows: after the shifting we can write the
| fraction part as f + delta, where 1 < f < 2^25, and 0 <= delta <= 2.
......@@ -2636,7 +3499,11 @@ Lround$to$nearest:
btst IMM (FLT_MANT_DIG),d0
beq 1f
lsrl IMM (1),d0
#ifndef __mcf5200__
addw IMM (1),d2
#else
addql IMM (1),d2
#endif
1:
| If bit #FLT_MANT_DIG-1 is clear we have a denormalized number, so we
| have to put the exponent to zero and return a denormalized number.
......
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