diff options
Diffstat (limited to 'sysdeps/x86_64/fpu')
| -rw-r--r-- | sysdeps/x86_64/fpu/e_powl.S | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/sysdeps/x86_64/fpu/e_powl.S b/sysdeps/x86_64/fpu/e_powl.S index 8c690e16cc..85f4deb3c7 100644 --- a/sysdeps/x86_64/fpu/e_powl.S +++ b/sysdeps/x86_64/fpu/e_powl.S @@ -1,5 +1,5 @@ /* ix87 specific implementation of pow function. - Copyright (C) 1996, 1997, 1998, 1999, 2001 Free Software Foundation, Inc. + Copyright (C) 1996, 1997, 1998, 1999, 2001, 2004 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996. @@ -48,6 +48,10 @@ one: .double 1.0 ASM_TYPE_DIRECTIVE(limit,@object) limit: .double 0.29 ASM_SIZE_DIRECTIVE(limit) + ASM_TYPE_DIRECTIVE(p63,@object) +p63: + .byte 0, 0, 0, 0, 0, 0, 0xe0, 0x43 + ASM_SIZE_DIRECTIVE(p63) #ifdef PIC #define MO(op) op##(%rip) @@ -87,6 +91,14 @@ ENTRY(__ieee754_powl) fxch // y : x + /* fistpll raises invalid exception for |y| >= 1L<<63. */ + fldl MO(p63) // 1L<<63 : y : x + fld %st(1) // y : 1L<<63 : y : x + fabs // |y| : 1L<<63 : y : x + fcomip %st(1), %st // 1L<<63 : y : x + fstp %st(0) // y : x + jnc 2f + /* First see whether `y' is a natural number. In this case we can use a more precise algorithm. */ fld %st // y : y : x @@ -148,6 +160,11 @@ ENTRY(__ieee754_powl) 7: fyl2x // log2(x) : y 8: fmul %st(1) // y*log2(x) : y + fxam + fnstsw + andb $0x45, %ah + cmpb $0x05, %ah // is y*log2(x) == ±inf ? + je 28f fst %st(1) // y*log2(x) : y*log2(x) frndint // int(y*log2(x)) : y*log2(x) fsubr %st, %st(1) // int(y*log2(x)) : fract(y*log2(x)) @@ -158,6 +175,11 @@ ENTRY(__ieee754_powl) fstp %st(1) // 2^fract(y*log2(x))*2^int(y*log2(x)) ret +28: fstp %st(1) // y*log2(x) + fldl MO(one) // 1 : y*log2(x) + fscale // 2^(y*log2(x)) : y*log2(x) + fstp %st(1) // 2^(y*log2(x)) + ret // pow(x,±0) = 1 .align ALIGNARG(4) |