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.global log1p .type log1p,@function log1p: mov 8(%esp),%eax fldln2 and $0x7fffffff,%eax fldl 4(%esp) cmp $0x3fd28f00,%eax ja 1f cmp $0x00100000,%eax jb 2f fyl2xp1 ret 1: fld1 faddp fyl2x ret # subnormal x, return x with underflow 2: fnstsw %ax and $16,%ax jnz 1f fsts 4(%esp) fstp %st(1) 1: ret