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Diffstat (limited to 'sysdeps/i386/fpu/e_powf.S')
-rw-r--r--sysdeps/i386/fpu/e_powf.S41
1 files changed, 30 insertions, 11 deletions
diff --git a/sysdeps/i386/fpu/e_powf.S b/sysdeps/i386/fpu/e_powf.S
index b3fa624f4d..c91545418d 100644
--- a/sysdeps/i386/fpu/e_powf.S
+++ b/sysdeps/i386/fpu/e_powf.S
@@ -1,5 +1,6 @@
/* ix87 specific implementation of pow function.
- Copyright (C) 1996, 1997, 1999, 2001, 2004 Free Software Foundation, Inc.
+ Copyright (C) 1996, 1997, 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.
@@ -66,9 +67,7 @@ ENTRY(__ieee754_powf)
fxam
#ifdef PIC
- call 1f
-1: popl %ecx
- addl $_GLOBAL_OFFSET_TABLE_+[.-1b], %ecx
+ LOAD_PIC_REG (cx)
#endif
fnstsw
@@ -86,6 +85,7 @@ ENTRY(__ieee754_powf)
flds 4(%esp) // x : y
subl $4, %esp
+ cfi_adjust_cfa_offset (4)
fxam
fnstsw
@@ -119,6 +119,7 @@ ENTRY(__ieee754_powf)
/* OK, we have an integer value for y. */
popl %edx
+ cfi_adjust_cfa_offset (-4)
orl $0, %edx
fstp %st(0) // x
jns 4f // y >= 0, jump
@@ -149,14 +150,16 @@ ENTRY(__ieee754_powf)
31: fstp %st(1)
ret
+ cfi_adjust_cfa_offset (4)
.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
@@ -175,6 +178,7 @@ ENTRY(__ieee754_powf)
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 $4, %esp
+ cfi_adjust_cfa_offset (-4)
fstp %st(1) // 2^fract(y*log2(x))*2^int(y*log2(x))
ret
@@ -188,9 +192,10 @@ ENTRY(__ieee754_powf)
// y == ±inf
.align ALIGNARG(4)
12: fstp %st(0) // pop y
- flds 4(%esp) // x
- fabs
- fcompl MO(one) // < 1, == 1, or > 1
+ fldl MO(one) // 1
+ flds 4(%esp) // x : 1
+ fabs // abs(x) : 1
+ fucompp // < 1, == 1, or > 1
fnstsw
andb $0x45, %ah
cmpb $0x45, %ah
@@ -213,6 +218,7 @@ ENTRY(__ieee754_powf)
13: flds 4(%esp) // load x == NaN
ret
+ cfi_adjust_cfa_offset (4)
.align ALIGNARG(4)
// x is ±inf
15: fstp %st(0) // y
@@ -231,6 +237,7 @@ ENTRY(__ieee754_powf)
// OK, the value is an integer, but is the number of bits small
// enough so that all are coming from the mantissa?
popl %edx
+ cfi_adjust_cfa_offset (-4)
testb $1, %dl
jz 18f // jump if not odd
movl %edx, %eax
@@ -244,22 +251,27 @@ ENTRY(__ieee754_powf)
fldl MOX(minf_mzero, %edx, 8)
ret
+ cfi_adjust_cfa_offset (4)
.align ALIGNARG(4)
16: fcompl MO(zero)
addl $4, %esp
+ cfi_adjust_cfa_offset (-4)
fnstsw
shrl $5, %eax
andl $8, %eax
fldl MOX(inf_zero, %eax, 1)
ret
+ cfi_adjust_cfa_offset (4)
.align ALIGNARG(4)
17: shll $30, %edx // sign bit for y in right position
addl $4, %esp
+ cfi_adjust_cfa_offset (-4)
18: shrl $31, %edx
fldl MOX(inf_zero, %edx, 8)
ret
+ cfi_adjust_cfa_offset (4)
.align ALIGNARG(4)
// x is ±0
20: fstp %st(0) // y
@@ -281,6 +293,7 @@ ENTRY(__ieee754_powf)
// OK, the value is an integer, but is the number of bits small
// enough so that all are coming from the mantissa?
popl %edx
+ cfi_adjust_cfa_offset (-4)
testb $1, %dl
jz 27f // jump if not odd
cmpl $0xff000000, %edx
@@ -292,13 +305,16 @@ ENTRY(__ieee754_powf)
fchs
ret
+ cfi_adjust_cfa_offset (4)
25: fstp %st(0)
26: addl $4, %esp
+ cfi_adjust_cfa_offset (-4)
27: // Raise divide-by-zero exception and get infinity value.
fldl MO(one)
fdivl MO(zero)
ret
+ cfi_adjust_cfa_offset (4)
.align ALIGNARG(4)
// x is ±0 and y is > 0. We must find out whether y is an odd integer.
21: testb $2, %dh
@@ -315,6 +331,7 @@ ENTRY(__ieee754_powf)
// OK, the value is an integer, but is the number of bits small
// enough so that all are coming from the mantissa?
popl %edx
+ cfi_adjust_cfa_offset (-4)
testb $1, %dl
jz 24f // jump if not odd
cmpl $0xff000000, %edx
@@ -323,8 +340,10 @@ ENTRY(__ieee754_powf)
fldl MO(mzero)
ret
+ cfi_adjust_cfa_offset (4)
22: fstp %st(0)
23: addl $4, %esp // Don't use pop.
+ cfi_adjust_cfa_offset (-4)
24: fldl MO(zero)
ret