Fix pow of zero and infinity to large powers.

This commit is contained in:
Joseph Myers 2012-03-21 12:14:57 +00:00
parent eb96ffb07d
commit 2460d3aa21
7 changed files with 373 additions and 33 deletions

View File

@ -1,3 +1,24 @@
2012-03-20 Joseph Myers <joseph@codesourcery.com>
[BZ #3866]
* sysdeps/i386/fpu/e_pow.S (__ieee754_pow): Test for y outside the
range of signed 64-bit integers before using fistpll. Remove
checks for whether integers fit in mantissa bits.
* sysdeps/i386/fpu/e_powf.S (__ieee754_powf): Test for y outside
the range of signed 32-bit integers before using fistpl. Remove
checks for whether integers fit in mantissa bits.
* sysdeps/i386/fpu/e_powl.S (p64): New object.
(__ieee754_powl): Test for y outside the range of signed 64-bit
integers before using fistpll. Reduce 64-bit values to 63-bit
ones as needed.
* sysdeps/ieee754/dbl-64/e_pow.c (__ieee754_pow): Ensure
divide-by-zero is raised for zero to large negative powers.
* sysdeps/x86_64/fpu/e_powl.S (p64): New object.
(__ieee754_powl): Test for y outside the range of signed 64-bit
integers before using fistpll. Reduce 64-bit values to 63-bit
ones as needed.
* math/libm-test.inc (pow_test): Add more tests.
2012-03-20 H.J. Lu <hongjiu.lu@intel.com>
* debug/backtracesymsfd.c: Include <_itoa.h> instead of

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@ -5431,11 +5431,75 @@ pow_test (void)
TEST_ff_f (pow, 0, -11, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(0,-odd) == ERANGE", errno, ERANGE, 0, 0, 0);
errno = 0;
TEST_ff_f (pow, 0, -0xffffff, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(0,-odd) == ERANGE", errno, ERANGE, 0, 0, 0);
#ifndef TEST_FLOAT
errno = 0;
TEST_ff_f (pow, 0, -0x1.fffffffffffffp+52L, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(0,-odd) == ERANGE", errno, ERANGE, 0, 0, 0);
#endif
#ifdef TEST_LDOUBLE
# if LDBL_MANT_DIG >= 64
errno = 0;
TEST_ff_f (pow, 0, -0x1.fffffffffffffffep+63L, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(0,-odd) == ERANGE", errno, ERANGE, 0, 0, 0);
# endif
# if LDBL_MANT_DIG >= 106
errno = 0;
TEST_ff_f (pow, 0, -0x1.ffffffffffffffffffffffffff8p+105L, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(0,-odd) == ERANGE", errno, ERANGE, 0, 0, 0);
# endif
# if LDBL_MANT_DIG >= 113
errno = 0;
TEST_ff_f (pow, 0, -0x1.ffffffffffffffffffffffffffffp+112L, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(0,-odd) == ERANGE", errno, ERANGE, 0, 0, 0);
# endif
#endif
TEST_ff_f (pow, minus_zero, -1, minus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(-0,-odd) == ERANGE", errno, ERANGE, 0, 0, 0);
errno = 0;
TEST_ff_f (pow, minus_zero, -11L, minus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(-0,-odd) == ERANGE", errno, ERANGE, 0, 0, 0);
errno = 0;
TEST_ff_f (pow, minus_zero, -0xffffff, minus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(-0,-odd) == ERANGE", errno, ERANGE, 0, 0, 0);
errno = 0;
TEST_ff_f (pow, minus_zero, -0x1fffffe, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(-0,-even) == ERANGE", errno, ERANGE, 0, 0, 0);
#ifndef TEST_FLOAT
errno = 0;
TEST_ff_f (pow, minus_zero, -0x1.fffffffffffffp+52L, minus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(-0,-odd) == ERANGE", errno, ERANGE, 0, 0, 0);
errno = 0;
TEST_ff_f (pow, minus_zero, -0x1.fffffffffffffp+53L, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(-0,-even) == ERANGE", errno, ERANGE, 0, 0, 0);
#endif
#ifdef TEST_LDOUBLE
# if LDBL_MANT_DIG >= 64
errno = 0;
TEST_ff_f (pow, minus_zero, -0x1.fffffffffffffffep+63L, minus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(-0,-odd) == ERANGE", errno, ERANGE, 0, 0, 0);
errno = 0;
TEST_ff_f (pow, minus_zero, -0x1.fffffffffffffffep+64L, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(-0,-even) == ERANGE", errno, ERANGE, 0, 0, 0);
# endif
# if LDBL_MANT_DIG >= 106
errno = 0;
TEST_ff_f (pow, minus_zero, -0x1.ffffffffffffffffffffffffff8p+105L, minus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(-0,-odd) == ERANGE", errno, ERANGE, 0, 0, 0);
errno = 0;
TEST_ff_f (pow, minus_zero, -0x1.ffffffffffffffffffffffffff8p+106L, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(-0,-even) == ERANGE", errno, ERANGE, 0, 0, 0);
# endif
# if LDBL_MANT_DIG >= 113
errno = 0;
TEST_ff_f (pow, minus_zero, -0x1.ffffffffffffffffffffffffffffp+112L, minus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(-0,-odd) == ERANGE", errno, ERANGE, 0, 0, 0);
errno = 0;
TEST_ff_f (pow, minus_zero, -0x1.ffffffffffffffffffffffffffffp+113L, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(-0,-even) == ERANGE", errno, ERANGE, 0, 0, 0);
# endif
#endif
errno = 0;
TEST_ff_f (pow, 0, -2, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
@ -5444,11 +5508,31 @@ pow_test (void)
TEST_ff_f (pow, 0, -11.1L, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(0,-num) == ERANGE", errno, ERANGE, 0, 0, 0);
errno = 0;
TEST_ff_f (pow, 0, -0x1p24, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(0,-num) == ERANGE", errno, ERANGE, 0, 0, 0);
errno = 0;
TEST_ff_f (pow, 0, -0x1p127, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(0,-num) == ERANGE", errno, ERANGE, 0, 0, 0);
errno = 0;
/* Bug 13879: spurious OVERFLOW exception may be present. */
TEST_ff_f (pow, 0, -max_value, plus_infty, DIVIDE_BY_ZERO_EXCEPTION|OVERFLOW_EXCEPTION_OK);
check_int ("errno for pow(0,-num) == ERANGE", errno, ERANGE, 0, 0, 0);
errno = 0;
TEST_ff_f (pow, minus_zero, -2, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(-0,-even) == ERANGE", errno, ERANGE, 0, 0, 0);
errno = 0;
TEST_ff_f (pow, minus_zero, -11.1L, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(-0,-num) == ERANGE", errno, ERANGE, 0, 0, 0);
errno = 0;
TEST_ff_f (pow, minus_zero, -0x1p24, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(-0,-num) == ERANGE", errno, ERANGE, 0, 0, 0);
errno = 0;
TEST_ff_f (pow, minus_zero, -0x1p127, plus_infty, DIVIDE_BY_ZERO_EXCEPTION);
check_int ("errno for pow(-0,-num) == ERANGE", errno, ERANGE, 0, 0, 0);
errno = 0;
/* Bug 13879: spurious OVERFLOW exception may be present. */
TEST_ff_f (pow, minus_zero, -max_value, plus_infty, DIVIDE_BY_ZERO_EXCEPTION|OVERFLOW_EXCEPTION_OK);
check_int ("errno for pow(-0,-num) == ERANGE", errno, ERANGE, 0, 0, 0);
TEST_ff_f (pow, 0x1p72L, 0x1p72L, plus_infty, OVERFLOW_EXCEPTION);
TEST_ff_f (pow, 10, -0x1p72L, 0);
@ -5487,32 +5571,155 @@ pow_test (void)
/* pow (+inf, y) == +inf for y > 0. */
TEST_ff_f (pow, plus_infty, 2, plus_infty);
TEST_ff_f (pow, plus_infty, 0xffffff, plus_infty);
#ifndef TEST_FLOAT
TEST_ff_f (pow, plus_infty, 0x1.fffffffffffffp+52L, plus_infty);
#endif
#ifdef TEST_LDOUBLE
# if LDBL_MANT_DIG >= 64
TEST_ff_f (pow, plus_infty, 0x1.fffffffffffffffep+63L, plus_infty);
# endif
# if LDBL_MANT_DIG >= 106
TEST_ff_f (pow, plus_infty, 0x1.ffffffffffffffffffffffffff8p+105L, plus_infty);
# endif
# if LDBL_MANT_DIG >= 113
TEST_ff_f (pow, plus_infty, 0x1.ffffffffffffffffffffffffffffp+112L, plus_infty);
# endif
#endif
TEST_ff_f (pow, plus_infty, 0x1p24, plus_infty);
TEST_ff_f (pow, plus_infty, 0x1p127, plus_infty);
TEST_ff_f (pow, plus_infty, max_value, plus_infty);
/* pow (+inf, y) == +0 for y < 0. */
TEST_ff_f (pow, plus_infty, -1, 0.0);
TEST_ff_f (pow, plus_infty, -0xffffff, 0.0);
#ifndef TEST_FLOAT
TEST_ff_f (pow, plus_infty, -0x1.fffffffffffffp+52L, 0.0);
#endif
#ifdef TEST_LDOUBLE
# if LDBL_MANT_DIG >= 64
TEST_ff_f (pow, plus_infty, -0x1.fffffffffffffffep+63L, 0.0);
# endif
# if LDBL_MANT_DIG >= 106
TEST_ff_f (pow, plus_infty, -0x1.ffffffffffffffffffffffffff8p+105L, 0.0);
# endif
# if LDBL_MANT_DIG >= 113
TEST_ff_f (pow, plus_infty, -0x1.ffffffffffffffffffffffffffffp+112L, 0.0);
# endif
#endif
TEST_ff_f (pow, plus_infty, -0x1p24, 0.0);
TEST_ff_f (pow, plus_infty, -0x1p127, 0.0);
TEST_ff_f (pow, plus_infty, -max_value, 0.0);
/* pow (-inf, y) == -inf for y an odd integer > 0. */
TEST_ff_f (pow, minus_infty, 27, minus_infty);
TEST_ff_f (pow, minus_infty, 0xffffff, minus_infty);
TEST_ff_f (pow, minus_infty, 0x1fffffe, plus_infty);
#ifndef TEST_FLOAT
TEST_ff_f (pow, minus_infty, 0x1.fffffffffffffp+52L, minus_infty);
TEST_ff_f (pow, minus_infty, 0x1.fffffffffffffp+53L, plus_infty);
#endif
#ifdef TEST_LDOUBLE
# if LDBL_MANT_DIG >= 64
TEST_ff_f (pow, minus_infty, 0x1.fffffffffffffffep+63L, minus_infty);
TEST_ff_f (pow, minus_infty, 0x1.fffffffffffffffep+64L, plus_infty);
# endif
# if LDBL_MANT_DIG >= 106
TEST_ff_f (pow, minus_infty, 0x1.ffffffffffffffffffffffffff8p+105L, minus_infty);
TEST_ff_f (pow, minus_infty, 0x1.ffffffffffffffffffffffffff8p+106L, plus_infty);
# endif
# if LDBL_MANT_DIG >= 113
TEST_ff_f (pow, minus_infty, 0x1.ffffffffffffffffffffffffffffp+112L, minus_infty);
TEST_ff_f (pow, minus_infty, 0x1.ffffffffffffffffffffffffffffp+113L, plus_infty);
# endif
#endif
/* pow (-inf, y) == +inf for y > 0 and not an odd integer. */
TEST_ff_f (pow, minus_infty, 28, plus_infty);
TEST_ff_f (pow, minus_infty, 0x1p24, plus_infty);
TEST_ff_f (pow, minus_infty, 0x1p127, plus_infty);
TEST_ff_f (pow, minus_infty, max_value, plus_infty);
/* pow (-inf, y) == -0 for y an odd integer < 0. */
TEST_ff_f (pow, minus_infty, -3, minus_zero);
TEST_ff_f (pow, minus_infty, -0xffffff, minus_zero);
TEST_ff_f (pow, minus_infty, -0x1fffffe, plus_zero);
#ifndef TEST_FLOAT
TEST_ff_f (pow, minus_infty, -0x1.fffffffffffffp+52L, minus_zero);
TEST_ff_f (pow, minus_infty, -0x1.fffffffffffffp+53L, plus_zero);
#endif
#ifdef TEST_LDOUBLE
# if LDBL_MANT_DIG >= 64
TEST_ff_f (pow, minus_infty, -0x1.fffffffffffffffep+63L, minus_zero);
TEST_ff_f (pow, minus_infty, -0x1.fffffffffffffffep+64L, plus_zero);
# endif
# if LDBL_MANT_DIG >= 106
TEST_ff_f (pow, minus_infty, -0x1.ffffffffffffffffffffffffff8p+105L, minus_zero);
TEST_ff_f (pow, minus_infty, -0x1.ffffffffffffffffffffffffff8p+106L, plus_zero);
# endif
# if LDBL_MANT_DIG >= 113
TEST_ff_f (pow, minus_infty, -0x1.ffffffffffffffffffffffffffffp+112L, minus_zero);
TEST_ff_f (pow, minus_infty, -0x1.ffffffffffffffffffffffffffffp+113L, plus_zero);
# endif
#endif
/* pow (-inf, y) == +0 for y < 0 and not an odd integer. */
TEST_ff_f (pow, minus_infty, -2.0, 0.0);
TEST_ff_f (pow, minus_infty, -0x1p24, 0.0);
TEST_ff_f (pow, minus_infty, -0x1p127, 0.0);
TEST_ff_f (pow, minus_infty, -max_value, 0.0);
/* pow (+0, y) == +0 for y an odd integer > 0. */
TEST_ff_f (pow, 0.0, 27, 0.0);
TEST_ff_f (pow, 0.0, 0xffffff, 0.0);
#ifndef TEST_FLOAT
TEST_ff_f (pow, 0.0, 0x1.fffffffffffffp+52L, 0.0);
#endif
#ifdef TEST_LDOUBLE
# if LDBL_MANT_DIG >= 64
TEST_ff_f (pow, 0.0, 0x1.fffffffffffffffep+63L, 0.0);
# endif
# if LDBL_MANT_DIG >= 106
TEST_ff_f (pow, 0.0, 0x1.ffffffffffffffffffffffffff8p+105L, 0.0);
# endif
# if LDBL_MANT_DIG >= 113
TEST_ff_f (pow, 0.0, 0x1.ffffffffffffffffffffffffffffp+112L, 0.0);
# endif
#endif
/* pow (-0, y) == -0 for y an odd integer > 0. */
TEST_ff_f (pow, minus_zero, 27, minus_zero);
TEST_ff_f (pow, minus_zero, 0xffffff, minus_zero);
TEST_ff_f (pow, minus_zero, 0x1fffffe, plus_zero);
#ifndef TEST_FLOAT
TEST_ff_f (pow, minus_zero, 0x1.fffffffffffffp+52L, minus_zero);
TEST_ff_f (pow, minus_zero, 0x1.fffffffffffffp+53L, plus_zero);
#endif
#ifdef TEST_LDOUBLE
# if LDBL_MANT_DIG >= 64
TEST_ff_f (pow, minus_zero, 0x1.fffffffffffffffep+63L, minus_zero);
TEST_ff_f (pow, minus_zero, 0x1.fffffffffffffffep+64L, plus_zero);
# endif
# if LDBL_MANT_DIG >= 106
TEST_ff_f (pow, minus_zero, 0x1.ffffffffffffffffffffffffff8p+105L, minus_zero);
TEST_ff_f (pow, minus_zero, 0x1.ffffffffffffffffffffffffff8p+106L, plus_zero);
# endif
# if LDBL_MANT_DIG >= 113
TEST_ff_f (pow, minus_zero, 0x1.ffffffffffffffffffffffffffffp+112L, minus_zero);
TEST_ff_f (pow, minus_zero, 0x1.ffffffffffffffffffffffffffffp+113L, plus_zero);
# endif
#endif
/* pow (+0, y) == +0 for y > 0 and not an odd integer. */
TEST_ff_f (pow, 0.0, 4, 0.0);
TEST_ff_f (pow, 0.0, 0x1p24, 0.0);
TEST_ff_f (pow, 0.0, 0x1p127, 0.0);
TEST_ff_f (pow, 0.0, max_value, 0.0);
/* pow (-0, y) == +0 for y > 0 and not an odd integer. */
TEST_ff_f (pow, minus_zero, 4, 0.0);
TEST_ff_f (pow, minus_zero, 0x1p24, 0.0);
TEST_ff_f (pow, minus_zero, 0x1p127, 0.0);
TEST_ff_f (pow, minus_zero, max_value, 0.0);
TEST_ff_f (pow, 16, 0.25L, 2);
TEST_ff_f (pow, 0x1p64L, 0.125L, 256);

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@ -230,6 +230,16 @@ ENTRY(__ieee754_pow)
testb $2, %dh
jz 16f // jump if x == +inf
// fistpll raises invalid exception for |y| >= 1L<<63, so test
// that (in which case y is certainly even) before testing
// whether y is odd.
fld %st // y : y
fabs // |y| : y
fcompl MO(p63) // y
fnstsw
sahf
jnc 16f
// We must find out whether y is an odd integer.
fld %st // y : y
fistpll (%esp) // y
@ -239,20 +249,13 @@ ENTRY(__ieee754_pow)
sahf
jne 17f
// OK, the value is an integer, but is the number of bits small
// enough so that all are coming from the mantissa?
// OK, the value is an integer.
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
orl %edx, %edx
jns 155f
negl %eax
155: cmpl $0x00200000, %eax
ja 18f // does not fit in mantissa bits
// It's an odd integer.
shrl $31, %edx
fldl MOX(minf_mzero, %edx, 8)
@ -289,6 +292,16 @@ ENTRY(__ieee754_pow)
testb $2, %dh
jz 25f
// fistpll raises invalid exception for |y| >= 1L<<63, so test
// that (in which case y is certainly even) before testing
// whether y is odd.
fld %st // y : y
fabs // |y| : y
fcompl MO(p63) // y
fnstsw
sahf
jnc 25f
fld %st // y : y
fistpll (%esp) // y
fildll (%esp) // int(y) : y
@ -297,16 +310,13 @@ ENTRY(__ieee754_pow)
sahf
jne 26f
// OK, the value is an integer, but is the number of bits small
// enough so that all are coming from the mantissa?
// OK, the value is an integer.
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
jbe 27f // does not fit in mantissa bits
// It's an odd integer.
// Raise divide-by-zero exception and get minus infinity value.
fldl MO(one)
@ -329,6 +339,14 @@ ENTRY(__ieee754_pow)
21: testb $2, %dh
jz 22f
// fistpll raises invalid exception for |y| >= 1L<<63, so test
// that (in which case y is certainly even) before testing
// whether y is odd.
fcoml MO(p63) // y
fnstsw
sahf
jnc 22f
fld %st // y : y
fistpll (%esp) // y
fildll (%esp) // int(y) : y
@ -337,16 +355,13 @@ ENTRY(__ieee754_pow)
sahf
jne 23f
// OK, the value is an integer, but is the number of bits small
// enough so that all are coming from the mantissa?
// OK, the value is an integer.
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
jae 24f // does not fit in mantissa bits
// It's an odd integer.
fldl MO(mzero)
ret

View File

@ -224,6 +224,16 @@ ENTRY(__ieee754_powf)
testb $2, %dh
jz 16f // jump if x == +inf
// fistpl raises invalid exception for |y| >= 1L<<31, so test
// that (in which case y is certainly even) before testing
// whether y is odd.
fld %st // y : y
fabs // |y| : y
fcompl MO(p31) // y
fnstsw
sahf
jnc 16f
// We must find out whether y is an odd integer.
fld %st // y : y
fistpl (%esp) // y
@ -233,18 +243,11 @@ ENTRY(__ieee754_powf)
sahf
jne 17f
// OK, the value is an integer, but is the number of bits small
// enough so that all are coming from the mantissa?
// OK, the value is an integer.
popl %edx
cfi_adjust_cfa_offset (-4)
testb $1, %dl
jz 18f // jump if not odd
movl %edx, %eax
orl %edx, %edx
jns 155f
negl %eax
155: cmpl $0x01000000, %eax
ja 18f // does not fit in mantissa bits
// It's an odd integer.
shrl $31, %edx
fldl MOX(minf_mzero, %edx, 8)
@ -281,6 +284,16 @@ ENTRY(__ieee754_powf)
testb $2, %dh
jz 25f
// fistpl raises invalid exception for |y| >= 1L<<31, so test
// that (in which case y is certainly even) before testing
// whether y is odd.
fld %st // y : y
fabs // |y| : y
fcompl MO(p31) // y
fnstsw
sahf
jnc 25f
fld %st // y : y
fistpl (%esp) // y
fildl (%esp) // int(y) : y
@ -289,14 +302,11 @@ ENTRY(__ieee754_powf)
sahf
jne 26f
// OK, the value is an integer, but is the number of bits small
// enough so that all are coming from the mantissa?
// OK, the value is an integer.
popl %edx
cfi_adjust_cfa_offset (-4)
testb $1, %dl
jz 27f // jump if not odd
cmpl $0xff000000, %edx
jbe 27f // does not fit in mantissa bits
// It's an odd integer.
// Raise divide-by-zero exception and get minus infinity value.
fldl MO(one)
@ -319,6 +329,14 @@ ENTRY(__ieee754_powf)
21: testb $2, %dh
jz 22f
// fistpl raises invalid exception for |y| >= 1L<<31, so test
// that (in which case y is certainly even) before testing
// whether y is odd.
fcoml MO(p31) // y
fnstsw
sahf
jnc 22f
fld %st // y : y
fistpl (%esp) // y
fildl (%esp) // int(y) : y
@ -327,14 +345,11 @@ ENTRY(__ieee754_powf)
sahf
jne 23f
// OK, the value is an integer, but is the number of bits small
// enough so that all are coming from the mantissa?
// OK, the value is an integer.
popl %edx
cfi_adjust_cfa_offset (-4)
testb $1, %dl
jz 24f // jump if not odd
cmpl $0xff000000, %edx
jae 24f // does not fit in mantissa bits
// It's an odd integer.
fldl MO(mzero)
ret

View File

@ -32,6 +32,9 @@ limit: .double 0.29
ASM_TYPE_DIRECTIVE(p63,@object)
p63: .byte 0, 0, 0, 0, 0, 0, 0xe0, 0x43
ASM_SIZE_DIRECTIVE(p63)
ASM_TYPE_DIRECTIVE(p64,@object)
p64: .byte 0, 0, 0, 0, 0, 0, 0xf0, 0x43
ASM_SIZE_DIRECTIVE(p64)
.section .rodata.cst16,"aM",@progbits,16
@ -243,6 +246,19 @@ ENTRY(__ieee754_powl)
testb $2, %dh
jz 16f // jump if x == +inf
// fistpll raises invalid exception for |y| >= 1L<<63, but y
// may be odd unless we know |y| >= 1L<<64.
fld %st // y : y
fabs // |y| : y
fcompl MO(p64) // y
fnstsw
sahf
jnc 16f
fldl MO(p63) // p63 : y
fxch // y : p63
fprem // y%p63 : p63
fstp %st(1) // y%p63
// We must find out whether y is an odd integer.
fld %st // y : y
fistpll (%esp) // y
@ -295,6 +311,19 @@ ENTRY(__ieee754_powl)
testb $2, %dh
jz 25f
// fistpll raises invalid exception for |y| >= 1L<<63, but y
// may be odd unless we know |y| >= 1L<<64.
fld %st // y : y
fabs // |y| : y
fcompl MO(p64) // y
fnstsw
sahf
jnc 25f
fldl MO(p63) // p63 : y
fxch // y : p63
fprem // y%p63 : p63
fstp %st(1) // y%p63
fld %st // y : y
fistpll (%esp) // y
fildll (%esp) // int(y) : y
@ -332,6 +361,18 @@ ENTRY(__ieee754_powl)
21: testb $2, %dh
jz 22f
// fistpll raises invalid exception for |y| >= 1L<<63, but y
// may be odd unless we know |y| >= 1L<<64.
fld %st // y : y
fcompl MO(p64) // y
fnstsw
sahf
jnc 22f
fldl MO(p63) // p63 : y
fxch // y : p63
fprem // y%p63 : p63
fstp %st(1) // y%p63
fld %st // y : y
fistpll (%esp) // y
fildll (%esp) // int(y) : y

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@ -111,7 +111,7 @@ __ieee754_pow(double x, double y) {
if (((v.i[HIGH_HALF] & 0x7fffffff) == 0x7ff00000 && v.i[LOW_HALF] != 0)
|| (v.i[HIGH_HALF] & 0x7fffffff) > 0x7ff00000)
return y;
if (ABS(y) > 1.0e20) return (y>0)?0:INF.x;
if (ABS(y) > 1.0e20) return (y>0)?0:1.0/ABS(x);
k = checkint(y);
if (k == -1)
return y < 0 ? 1.0/x : x;

View File

@ -32,6 +32,9 @@ limit: .double 0.29
ASM_TYPE_DIRECTIVE(p63,@object)
p63: .byte 0, 0, 0, 0, 0, 0, 0xe0, 0x43
ASM_SIZE_DIRECTIVE(p63)
ASM_TYPE_DIRECTIVE(p64,@object)
p64: .byte 0, 0, 0, 0, 0, 0, 0xf0, 0x43
ASM_SIZE_DIRECTIVE(p64)
.section .rodata.cst16,"aM",@progbits,16
@ -227,6 +230,19 @@ ENTRY(__ieee754_powl)
testb $2, %dh
jz 16f // jump if x == +inf
// fistpll raises invalid exception for |y| >= 1L<<63, but y
// may be odd unless we know |y| >= 1L<<64.
fldl MO(p64) // 1L<<64 : y
fld %st(1) // y : 1L<<64 : y
fabs // |y| : 1L<<64 : y
fcomip %st(1), %st // 1L<<64 : y
fstp %st(0) // y
jnc 16f
fldl MO(p63) // p63 : y
fxch // y : p63
fprem // y%p63 : p63
fstp %st(1) // y%p63
// We must find out whether y is an odd integer.
fld %st // y : y
fistpll -8(%rsp) // y
@ -284,6 +300,19 @@ ENTRY(__ieee754_powl)
testb $2, %dh
jz 25f
// fistpll raises invalid exception for |y| >= 1L<<63, but y
// may be odd unless we know |y| >= 1L<<64.
fldl MO(p64) // 1L<<64 : y
fld %st(1) // y : 1L<<64 : y
fabs // |y| : 1L<<64 : y
fcomip %st(1), %st // 1L<<64 : y
fstp %st(0) // y
jnc 25f
fldl MO(p63) // p63 : y
fxch // y : p63
fprem // y%p63 : p63
fstp %st(1) // y%p63
fld %st // y : y
fistpll -8(%rsp) // y
fildll -8(%rsp) // int(y) : y
@ -315,6 +344,18 @@ ENTRY(__ieee754_powl)
21: testb $2, %dh
jz 22f
// fistpll raises invalid exception for |y| >= 1L<<63, but y
// may be odd unless we know |y| >= 1L<<64.
fldl MO(p64) // 1L<<64 : y
fxch // y : 1L<<64
fcomi %st(1), %st // y : 1L<<64
fstp %st(1) // y
jnc 22f
fldl MO(p63) // p63 : y
fxch // y : p63
fprem // y%p63 : p63
fstp %st(1) // y%p63
fld %st // y : y
fistpll -8(%rsp) // y
fildll -8(%rsp) // int(y) : y