/* Compute the hypothenuse of X and Y. Copyright (C) 1998-2021 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see <https://www.gnu.org/licenses/>. */ #include <sysdep.h> #include <i386-math-asm.h> #include <libm-alias-finite.h> .text ENTRY(__ieee754_hypotf) flds 4(%esp) // x fxam fnstsw flds 8(%esp) // y : x movb %ah, %ch fxam fnstsw movb %ah, %al orb %ch, %ah sahf jc 1f fmul %st(0) // y * y : x fxch // x : y * y fmul %st(0) // x * x : y * y faddp // x * x + y * y fsqrt FLT_NARROW_EVAL 2: ret // We have to test whether any of the parameters is Inf. // In this case the result is infinity. 1: andb $0x45, %al cmpb $5, %al je 3f // jump if y is Inf andb $0x45, %ch cmpb $5, %ch jne 4f // jump if x is not Inf fxch 3: fstp %st(1) fabs jmp 2b 4: testb $1, %al jnz 5f // y is NaN fxch 5: fstp %st(1) jmp 2b END(__ieee754_hypotf) libm_alias_finite (__ieee754_hypotf, __hypotf)