.global expm1f
.type expm1f,@function
expm1f:
flds 4(%esp)
mov 4(%esp),%eax
add %eax,%eax
cmp $0x01000000,%eax
jae 1f
# subnormal x, return x with underflow
fnstsw %ax
and $16,%ax
jnz 2f
fld %st(0)
fmul %st(1)
fstps 4(%esp)
2: ret
.global expm1l
.type expm1l,@function
expm1l:
fldt 4(%esp)
jmp 1f
.global expm1
.type expm1,@function
expm1:
fldl 4(%esp)
mov 8(%esp),%eax
add %eax,%eax
cmp $0x00200000,%eax
jae 1f
# subnormal x, return x with underflow
fnstsw %ax
and $16,%ax
jnz 2f
fsts 4(%esp)
2: ret
1: fldl2e
fmulp
mov $0xc2820000,%eax
push %eax
flds (%esp)
pop %eax
fucomp %st(1)
fnstsw %ax
sahf
fld1
jb 1f
# x*log2e < -65, return -1 without underflow
fstp %st(1)
fchs
ret
1: fld %st(1)
fabs
fucom %st(1)
fnstsw %ax
fstp %st(0)
fstp %st(0)
sahf
ja 1f
f2xm1
ret
1: call 1f
fld1
fsubrp
ret
.global exp2f
.type exp2f,@function
exp2f:
flds 4(%esp)
jmp 1f
.global exp2l
.type exp2l,@function
exp2l:
fldt 4(%esp)
jmp 1f
.global expf
.type expf,@function
expf:
flds 4(%esp)
jmp 2f
.global exp
.type exp,@function
exp:
fldl 4(%esp)
2: fldl2e
fmulp
jmp 1f
.global exp2
.type exp2,@function
exp2:
fldl 4(%esp)
1: pushl $0x467ff000
flds (%esp) # 16380
xorl %eax,%eax
pushl $0x80000000
push %eax
fld %st(1)
fabs
fucomp %st(1)
fnstsw
fstp %st(0)
sahf
ja 3f # |x| > 16380
jp 2f # x is nan (avoid invalid except in fistp)
fld %st(0)
fistpl 8(%esp)
fildl 8(%esp)
fxch %st(1)
fsub %st(1)
mov $0x3fff,%eax
add %eax,8(%esp)
f2xm1
fld1
faddp # 2^(x-rint(x))
fldt (%esp) # 2^rint(x)
fmulp
fstp %st(1)
2: add $12,%esp
ret
3: fld %st(0)
fstpt (%esp)
fld1
mov 8(%esp),%ax
and $0x7fff,%ax
cmp $0x7fff,%ax
je 1f # x = +-inf
fld %st(1)
frndint
fxch %st(2)
fsub %st(2) # st(0)=x-rint(x), st(1)=1, st(2)=rint(x)
f2xm1
faddp # 2^(x-rint(x))
1: fscale
fstp %st(1)
add $12,%esp
ret
