diff options
Diffstat (limited to 'src/math/i386/exp_ld.s')
-rw-r--r-- | src/math/i386/exp_ld.s | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/src/math/i386/exp_ld.s b/src/math/i386/exp_ld.s new file mode 100644 index 00000000..99cba01f --- /dev/null +++ b/src/math/i386/exp_ld.s @@ -0,0 +1,93 @@ +.global expm1l +.type expm1l,@function +expm1l: + fldt 4(%esp) + 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 exp2l +.global __exp2l +.hidden __exp2l +.type exp2l,@function +exp2l: +__exp2l: + fldt 4(%esp) +1: sub $12,%esp + fld %st(0) + fstpt (%esp) + mov 8(%esp),%ax + and $0x7fff,%ax + cmp $0x3fff+13,%ax + jb 4f # |x| < 8192 + cmp $0x3fff+15,%ax + jae 3f # |x| >= 32768 + fsts (%esp) + cmpl $0xc67ff800,(%esp) + jb 2f # x > -16382 + movl $0x5f000000,(%esp) + flds (%esp) # 0x1p63 + fld %st(1) + fsub %st(1) + faddp + fucomp %st(1) + fnstsw + sahf + je 2f # x - 0x1p63 + 0x1p63 == x + movl $1,(%esp) + flds (%esp) # 0x1p-149 + fdiv %st(1) + fstps (%esp) # raise underflow +2: fld1 + 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 +3: xor %eax,%eax +4: cmp $0x3fff-64,%ax + fld1 + jb 1b # |x| < 0x1p-64 + fstpt (%esp) + fistl 8(%esp) + fildl 8(%esp) + fsubrp %st(1) + addl $0x3fff,8(%esp) + f2xm1 + fld1 + faddp # 2^(x-rint(x)) + fldt (%esp) # 2^rint(x) + fmulp + add $12,%esp + ret |