math: move x86_64 exp2l implementation to exp2l.s from expl.s

This commit is contained in:
Szabolcs Nagy 2012-12-16 17:28:18 +01:00
parent 1d7c4f8f93
commit 525ad96e0e
3 changed files with 76 additions and 85 deletions

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@ -1 +1,75 @@
# see expl.s
.global expm1l
.type expm1l,@function
expm1l:
fldt 8(%rsp)
fldl2e
fmulp
fld1
fld %st(1)
fabs
fucom %st(1)
fnstsw %ax
fstp %st(0)
fstp %st(0)
sahf
ja 1f
f2xm1
ret
1: push %rax
call 1f
pop %rax
fld1
fsubrp
ret
.global exp2l
.type exp2l,@function
exp2l:
fldt 8(%rsp)
1: mov $0x467ff000,%eax
mov %eax,-16(%rsp)
mov $0x80000000,%eax
mov %eax,-20(%rsp)
xor %eax,%eax
mov %eax,-24(%rsp)
flds -16(%rsp) # 16380
fld %st(1)
fabs
fucom %st(1)
fnstsw
fstp %st(0)
fstp %st(0)
sahf
ja 3f # |x| > 16380
jp 2f # x is nan (avoid invalid except in fistp)
fld %st(0)
fistpl -16(%rsp)
fildl -16(%rsp)
fxch %st(1)
fsub %st(1)
mov $0x3fff,%eax
add %eax,-16(%rsp)
f2xm1
fld1
faddp # 2^(x-rint(x))
fldt -24(%rsp) # 2^rint(x)
fmulp
2: fstp %st(1)
ret
3: fld %st(0)
fstpt -24(%rsp)
fld1
mov -15(%rsp),%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)
ret

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@ -1,83 +0,0 @@
.global expm1l
.type expm1l,@function
expm1l:
fldt 8(%rsp)
1: fldl2e
fmulp
fld1
fld %st(1)
fabs
fucom %st(1)
fnstsw %ax
fstp %st(0)
fstp %st(0)
sahf
ja 1f
f2xm1
ret
1: push %rax
call 1f
pop %rax
fld1
fsubrp
ret
.global expl
.type expl,@function
expl:
fldt 8(%rsp)
fldl2e
fmulp
jmp 1f
.global exp2l
.type exp2l,@function
exp2l:
fldt 8(%rsp)
1: mov $0x467ff000,%eax
mov %eax,-16(%rsp)
mov $0x80000000,%eax
mov %eax,-20(%rsp)
xor %eax,%eax
mov %eax,-24(%rsp)
flds -16(%rsp) # 16380
fld %st(1)
fabs
fucom %st(1)
fnstsw
fstp %st(0)
fstp %st(0)
sahf
ja 3f # |x| > 16380
jp 2f # x is nan (avoid invalid except in fistp)
fld %st(0)
fistpl -16(%rsp)
fildl -16(%rsp)
fxch %st(1)
fsub %st(1)
mov $0x3fff,%eax
add %eax,-16(%rsp)
f2xm1
fld1
faddp # 2^(x-rint(x))
fldt -24(%rsp) # 2^rint(x)
fmulp
2: fstp %st(1)
ret
3: fld %st(0)
fstpt -24(%rsp)
fld1
mov -15(%rsp),%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)
ret

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@ -1 +1 @@
# see expm1.s
# see exp2l.s