diff options
Diffstat (limited to 'sysdeps/i386/fpu/e_pow.S')
-rw-r--r-- | sysdeps/i386/fpu/e_pow.S | 44 |
1 files changed, 33 insertions, 11 deletions
diff --git a/sysdeps/i386/fpu/e_pow.S b/sysdeps/i386/fpu/e_pow.S index d100c0ac57..792f926902 100644 --- a/sysdeps/i386/fpu/e_pow.S +++ b/sysdeps/i386/fpu/e_pow.S @@ -1,5 +1,5 @@ /* ix87 specific implementation of pow function. - Copyright (C) 1996, 1997, 1998, 1999, 2001, 2004 + Copyright (C) 1996, 1997, 1998, 1999, 2001, 2004, 2005, 2007 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996. @@ -67,9 +67,7 @@ ENTRY(__ieee754_pow) fxam #ifdef PIC - call 1f -1: popl %ecx - addl $_GLOBAL_OFFSET_TABLE_+[.-1b], %ecx + LOAD_PIC_REG (cx) #endif fnstsw @@ -87,6 +85,7 @@ ENTRY(__ieee754_pow) fldl 4(%esp) // x : y subl $8,%esp + cfi_adjust_cfa_offset (8) fxam fnstsw @@ -120,7 +119,9 @@ ENTRY(__ieee754_pow) /* OK, we have an integer value for y. */ popl %eax + cfi_adjust_cfa_offset (-4) popl %edx + cfi_adjust_cfa_offset (-4) orl $0, %edx fstp %st(0) // x jns 4f // y >= 0, jump @@ -155,14 +156,16 @@ ENTRY(__ieee754_pow) 31: fstp %st(1) ret + cfi_adjust_cfa_offset (8) .align ALIGNARG(4) 2: /* y is a real number. */ fxch // x : y fldl MO(one) // 1.0 : x : y - fld %st(1) // x : 1.0 : x : y - fsub %st(1) // x-1 : 1.0 : x : y - fabs // |x-1| : 1.0 : x : y - fcompl MO(limit) // 1.0 : x : y + fldl MO(limit) // 0.29 : 1.0 : x : y + fld %st(2) // x : 0.29 : 1.0 : x : y + fsub %st(2) // x-1 : 0.29 : 1.0 : x : y + fabs // |x-1| : 0.29 : 1.0 : x : y + fucompp // 1.0 : x : y fnstsw fxch // x : 1.0 : y sahf @@ -181,6 +184,7 @@ ENTRY(__ieee754_pow) faddl MO(one) // 2^fract(y*log2(x)) : int(y*log2(x)) fscale // 2^fract(y*log2(x))*2^int(y*log2(x)) : int(y*log2(x)) addl $8, %esp + cfi_adjust_cfa_offset (-8) fstp %st(1) // 2^fract(y*log2(x))*2^int(y*log2(x)) ret @@ -194,9 +198,10 @@ ENTRY(__ieee754_pow) // y == ±inf .align ALIGNARG(4) 12: fstp %st(0) // pop y - fldl 4(%esp) // x - fabs - fcompl MO(one) // < 1, == 1, or > 1 + fldl MO(one) // 1 + fldl 4(%esp) // x : 1 + fabs // abs(x) : 1 + fucompp // < 1, == 1, or > 1 fnstsw andb $0x45, %ah cmpb $0x45, %ah @@ -219,6 +224,7 @@ ENTRY(__ieee754_pow) 13: fldl 4(%esp) // load x == NaN ret + cfi_adjust_cfa_offset (8) .align ALIGNARG(4) // x is ±inf 15: fstp %st(0) // y @@ -237,7 +243,9 @@ ENTRY(__ieee754_pow) // OK, the value is an integer, but is the number of bits small // enough so that all are coming from the mantissa? popl %eax + cfi_adjust_cfa_offset (-4) popl %edx + cfi_adjust_cfa_offset (-4) andb $1, %al jz 18f // jump if not odd movl %edx, %eax @@ -251,22 +259,27 @@ ENTRY(__ieee754_pow) fldl MOX(minf_mzero, %edx, 8) ret + cfi_adjust_cfa_offset (8) .align ALIGNARG(4) 16: fcompl MO(zero) addl $8, %esp + cfi_adjust_cfa_offset (-8) fnstsw shrl $5, %eax andl $8, %eax fldl MOX(inf_zero, %eax, 1) ret + cfi_adjust_cfa_offset (8) .align ALIGNARG(4) 17: shll $30, %edx // sign bit for y in right position addl $8, %esp + cfi_adjust_cfa_offset (-8) 18: shrl $31, %edx fldl MOX(inf_zero, %edx, 8) ret + cfi_adjust_cfa_offset (8) .align ALIGNARG(4) // x is ±0 20: fstp %st(0) // y @@ -288,7 +301,9 @@ ENTRY(__ieee754_pow) // OK, the value is an integer, but is the number of bits small // enough so that all are coming from the mantissa? popl %eax + cfi_adjust_cfa_offset (-4) popl %edx + cfi_adjust_cfa_offset (-4) andb $1, %al jz 27f // jump if not odd cmpl $0xffe00000, %edx @@ -300,13 +315,16 @@ ENTRY(__ieee754_pow) fchs ret + cfi_adjust_cfa_offset (8) 25: fstp %st(0) 26: addl $8, %esp + cfi_adjust_cfa_offset (-8) 27: // Raise divide-by-zero exception and get infinity value. fldl MO(one) fdivl MO(zero) ret + cfi_adjust_cfa_offset (8) .align ALIGNARG(4) // x is ±0 and y is > 0. We must find out whether y is an odd integer. 21: testb $2, %dh @@ -323,7 +341,9 @@ ENTRY(__ieee754_pow) // OK, the value is an integer, but is the number of bits small // enough so that all are coming from the mantissa? popl %eax + cfi_adjust_cfa_offset (-4) popl %edx + cfi_adjust_cfa_offset (-4) andb $1, %al jz 24f // jump if not odd cmpl $0xffe00000, %edx @@ -332,8 +352,10 @@ ENTRY(__ieee754_pow) fldl MO(mzero) ret + cfi_adjust_cfa_offset (8) 22: fstp %st(0) 23: addl $8, %esp // Don't use 2 x pop + cfi_adjust_cfa_offset (-8) 24: fldl MO(zero) ret |