Fix x86, x86_64 fmax, fmin sNaN handling, add tests (bug 20947).

Various fmax and fmin function implementations mishandle sNaN
arguments:

(a) When both arguments are NaNs, the return value should be a qNaN,
but sometimes it is an sNaN if at least one argument is an sNaN.

(b) Under TS 18661-1 semantics, if either argument is an sNaN then the
result should be a qNaN (whereas if one argument is a qNaN and the
other is not a NaN, the result should be the non-NaN argument).
Various implementations treat sNaNs like qNaNs here.

This patch fixes the x86 and x86_64 versions (ignoring float and
double for 32-bit x86 given the inability to reliably avoid the sNaN
turning into a qNaN before it gets to the called function).  Tests of
sNaN inputs to these functions are added.

Note on architecture versions I haven't changed for this issue:
AArch64 already gets this right (it uses a hardware instruction with
the correct semantics for both quiet and signaling NaNs) and does not
need changes.  It's possible Alpha, IA64, SPARC might need changes
(this would be shown by the testsuite if so).

Tested for x86_64 and x86 (both i686 and i586 builds, to cover the
different x86 implementations).

	[BZ #20947]
	* sysdeps/i386/fpu/s_fmaxl.S (__fmaxl): Add the arguments when
	either is a signaling NaN.
	* sysdeps/i386/fpu/s_fminl.S (__fminl): Likewise.  Make code
	follow fmaxl more closely.
	* sysdeps/i386/i686/fpu/s_fmaxl.S (__fmaxl): Add the arguments
	when either is a signaling NaN.
	* sysdeps/i386/i686/fpu/s_fminl.S (__fminl): Likewise.
	* sysdeps/x86_64/fpu/s_fmax.S (__fmax): Likewise.
	* sysdeps/x86_64/fpu/s_fmaxf.S (__fmaxf): Likewise.
	* sysdeps/x86_64/fpu/s_fmaxl.S (__fmaxl): Likewise.
	* sysdeps/x86_64/fpu/s_fmin.S (__fmin): Likewise.
	* sysdeps/x86_64/fpu/s_fminf.S (__fminf): Likewise.
	* sysdeps/x86_64/fpu/s_fminl.S (__fminl): Likewise.
	* math/libm-test.inc (fmax_test_data): Add tests of sNaN inputs.
	(fmin_test_data): Likewise.
This commit is contained in:
Joseph Myers 2016-12-15 23:52:18 +00:00
parent 67f779f1ea
commit 0a2546cdaa
12 changed files with 322 additions and 27 deletions

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@ -1,3 +1,22 @@
2016-12-15 Joseph Myers <joseph@codesourcery.com>
[BZ #20947]
* sysdeps/i386/fpu/s_fmaxl.S (__fmaxl): Add the arguments when
either is a signaling NaN.
* sysdeps/i386/fpu/s_fminl.S (__fminl): Likewise. Make code
follow fmaxl more closely.
* sysdeps/i386/i686/fpu/s_fmaxl.S (__fmaxl): Add the arguments
when either is a signaling NaN.
* sysdeps/i386/i686/fpu/s_fminl.S (__fminl): Likewise.
* sysdeps/x86_64/fpu/s_fmax.S (__fmax): Likewise.
* sysdeps/x86_64/fpu/s_fmaxf.S (__fmaxf): Likewise.
* sysdeps/x86_64/fpu/s_fmaxl.S (__fmaxl): Likewise.
* sysdeps/x86_64/fpu/s_fmin.S (__fmin): Likewise.
* sysdeps/x86_64/fpu/s_fminf.S (__fminf): Likewise.
* sysdeps/x86_64/fpu/s_fminl.S (__fminl): Likewise.
* math/libm-test.inc (fmax_test_data): Add tests of sNaN inputs.
(fmin_test_data): Likewise.
2016-12-15 Andreas Schwab <schwab@suse.de>
* support/support_test_main.c (support_test_main): Don't shadow

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@ -7799,6 +7799,14 @@ static const struct test_ff_f_data fmax_test_data[] =
TEST_ff_f (fmax, 9, -qnan_value, 9, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, -9, qnan_value, -9, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, -9, -qnan_value, -9, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, 0, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, 0, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, minus_zero, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, minus_zero, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, 9, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, 9, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, -9, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, -9, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, qnan_value, 0, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, -qnan_value, 0, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, qnan_value, minus_zero, minus_zero, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
@ -7807,18 +7815,46 @@ static const struct test_ff_f_data fmax_test_data[] =
TEST_ff_f (fmax, -qnan_value, 9, 9, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, qnan_value, -9, -9, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, -qnan_value, -9, -9, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, snan_value, 0, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, -snan_value, 0, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, snan_value, minus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, -snan_value, minus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, snan_value, 9, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, -snan_value, 9, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, snan_value, -9, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, -snan_value, -9, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, plus_infty, qnan_value, plus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, plus_infty, -qnan_value, plus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, minus_infty, qnan_value, minus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, minus_infty, -qnan_value, minus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, plus_infty, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, plus_infty, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, minus_infty, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, minus_infty, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, qnan_value, plus_infty, plus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, -qnan_value, plus_infty, plus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, qnan_value, minus_infty, minus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, -qnan_value, minus_infty, minus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, snan_value, plus_infty, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, -snan_value, plus_infty, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, snan_value, minus_infty, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, -snan_value, minus_infty, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, qnan_value, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, qnan_value, -qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, -qnan_value, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, -qnan_value, -qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmax, qnan_value, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, qnan_value, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, -qnan_value, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, -qnan_value, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, snan_value, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, snan_value, -qnan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, -snan_value, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, -snan_value, -qnan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, snan_value, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, snan_value, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, -snan_value, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmax, -snan_value, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
};
static void
@ -7862,6 +7898,14 @@ static const struct test_ff_f_data fmin_test_data[] =
TEST_ff_f (fmin, 9, -qnan_value, 9, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, -9, qnan_value, -9, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, -9, -qnan_value, -9, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, 0, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, 0, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, minus_zero, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, minus_zero, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, 9, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, 9, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, -9, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, -9, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, qnan_value, 0, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, -qnan_value, 0, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, qnan_value, minus_zero, minus_zero, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
@ -7870,18 +7914,46 @@ static const struct test_ff_f_data fmin_test_data[] =
TEST_ff_f (fmin, -qnan_value, 9, 9, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, qnan_value, -9, -9, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, -qnan_value, -9, -9, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, snan_value, 0, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, -snan_value, 0, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, snan_value, minus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, -snan_value, minus_zero, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, snan_value, 9, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, -snan_value, 9, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, snan_value, -9, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, -snan_value, -9, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, plus_infty, qnan_value, plus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, plus_infty, -qnan_value, plus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, minus_infty, qnan_value, minus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, minus_infty, -qnan_value, minus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, plus_infty, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, plus_infty, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, minus_infty, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, minus_infty, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, qnan_value, plus_infty, plus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, -qnan_value, plus_infty, plus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, qnan_value, minus_infty, minus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, -qnan_value, minus_infty, minus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, snan_value, plus_infty, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, -snan_value, plus_infty, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, snan_value, minus_infty, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, -snan_value, minus_infty, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, qnan_value, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, qnan_value, -qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, -qnan_value, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, -qnan_value, -qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_ff_f (fmin, qnan_value, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, qnan_value, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, -qnan_value, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, -qnan_value, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, snan_value, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, snan_value, -qnan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, -snan_value, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, -snan_value, -qnan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, snan_value, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, snan_value, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, -snan_value, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
TEST_ff_f (fmin, -snan_value, -snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
};
static void

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@ -28,7 +28,13 @@ ENTRY(__fmaxl)
andb $0x45, %ah
cmpb $0x01, %ah
je 1f // y == NaN
je 2f // y == NaN
fxam
fnstsw
andb $0x45, %ah
cmpb $0x01, %ah
je 3f // x == NaN
fucom %st(1)
fnstsw
@ -39,5 +45,27 @@ ENTRY(__fmaxl)
1: fstp %st(1)
ret
2: // st(1) is a NaN; st(0) may or may not be.
fxam
fnstsw
andb $0x45, %ah
cmpb $0x01, %ah
je 4f
// st(1) is a NaN; st(0) is not. Test if st(1) is signaling.
testb $0x40, 23(%esp)
jz 4f
fstp %st(1)
ret
3: // st(0) is a NaN; st(1) is not. Test if st(0) is signaling.
testb $0x40, 11(%esp)
jz 4f
fstp %st(0)
ret
4: // Both arguments are NaNs, or one is a signaling NaN.
faddp
ret
END(__fmaxl)
weak_alias (__fmaxl, fmaxl)

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@ -21,23 +21,51 @@
.text
ENTRY(__fminl)
fldt 4(%esp) // x
fldt 16(%esp) // x : y
fldt 16(%esp) // y
fxam
fnstsw
fldt 4(%esp) // y : x
andb $0x45, %ah
cmpb $0x01, %ah
je 2f // y == NaN
fxam
fnstsw
andb $0x45, %ah
cmpb $0x01, %ah
je 1f // y == NaN
je 3f // x == NaN
fucom %st(1)
fnstsw
sahf
jc 2f
jc 1f
1: fxch %st(1)
2: fstp %st(1)
fxch %st(1)
1: fstp %st(1)
ret
2: // st(1) is a NaN; st(0) may or may not be.
fxam
fnstsw
andb $0x45, %ah
cmpb $0x01, %ah
je 4f
// st(1) is a NaN; st(0) is not. Test if st(1) is signaling.
testb $0x40, 23(%esp)
jz 4f
fstp %st(1)
ret
3: // st(0) is a NaN; st(1) is not. Test if st(0) is signaling.
testb $0x40, 11(%esp)
jz 4f
fstp %st(0)
ret
4: // Both arguments are NaNs, or one is a signaling NaN.
faddp
ret
END(__fminl)
weak_alias (__fminl, fminl)

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@ -24,16 +24,35 @@ ENTRY(__fmaxl)
fldt 4(%esp) // x
fldt 16(%esp) // x : y
fucomi %st(0), %st
fcmovu %st(1), %st // now %st contains y if not NaN, x otherwise
fxch
fucomi %st(1), %st
jp 2f
fcmovb %st(1), %st
fstp %st(1)
ret
2: // Unordered.
fucomi %st(0), %st
jp 3f
// st(1) is a NaN; st(0) is not. Test if st(1) is signaling.
testb $0x40, 11(%esp)
jz 4f
fstp %st(1)
ret
3: // st(0) is a NaN; st(1) may or may not be.
fxch
fucomi %st(0), %st
jp 4f
// st(1) is a NaN; st(0) is not. Test if st(1) is signaling.
testb $0x40, 23(%esp)
jz 4f
fstp %st(1)
ret
4: // Both arguments are NaNs, or one is a signaling NaN.
faddp
ret
END(__fmaxl)
weak_alias (__fmaxl, fmaxl)

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@ -24,14 +24,35 @@ ENTRY(__fminl)
fldt 4(%esp) // x
fldt 16(%esp) // x : y
fucomi %st(0), %st
fcmovu %st(1), %st // now %st contains y if not NaN, x otherwise
fucomi %st(1), %st
jp 2f
fcmovnb %st(1), %st
fstp %st(1)
ret
2: // Unordered.
fucomi %st(0), %st
jp 3f
// st(1) is a NaN; st(0) is not. Test if st(1) is signaling.
testb $0x40, 11(%esp)
jz 4f
fstp %st(1)
ret
3: // st(0) is a NaN; st(1) may or may not be.
fxch
fucomi %st(0), %st
jp 4f
// st(1) is a NaN; st(0) is not. Test if st(1) is signaling.
testb $0x40, 23(%esp)
jz 4f
fstp %st(1)
ret
4: // Both arguments are NaNs, or one is a signaling NaN.
faddp
ret
END(__fminl)
weak_alias (__fminl, fminl)

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@ -27,8 +27,25 @@ ENTRY(__fmax)
jmp 2f
1: ucomisd %xmm1, %xmm1 // Is xmm1 a NaN?
jp 2f // then return xmm0
jp 3f
// xmm0 is a NaN; xmm1 is not. Test if xmm0 is signaling.
movsd %xmm0, -8(%rsp)
testb $0x8, -2(%rsp)
jz 4f
movsd %xmm1, %xmm0 // otherwise return xmm1
ret
3: // xmm1 is a NaN; xmm0 may or may not be.
ucomisd %xmm0, %xmm0
jp 4f
// xmm1 is a NaN; xmm0 is not. Test if xmm1 is signaling.
movsd %xmm1, -8(%rsp)
testb $0x8, -2(%rsp)
jz 4f
ret
4: // Both arguments are NaNs, or one is a signaling NaN.
addsd %xmm1, %xmm0
2: ret
END(__fmax)

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@ -27,8 +27,25 @@ ENTRY(__fmaxf)
jmp 2f
1: ucomiss %xmm1, %xmm1 // Is xmm1 a NaN?
jp 2f // then return xmm0
jp 3f
// xmm0 is a NaN; xmm1 is not. Test if xmm0 is signaling.
movss %xmm0, -4(%rsp)
testb $0x40, -2(%rsp)
jz 4f
movss %xmm1, %xmm0 // otherwise return xmm1
ret
3: // xmm1 is a NaN; xmm0 may or may not be.
ucomiss %xmm0, %xmm0
jp 4f
// xmm1 is a NaN; xmm0 is not. Test if xmm1 is signaling.
movss %xmm1, -4(%rsp)
testb $0x40, -2(%rsp)
jz 4f
ret
4: // Both arguments are NaNs, or one is a signaling NaN.
addss %xmm1, %xmm0
2: ret
END(__fmaxf)

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@ -24,16 +24,35 @@ ENTRY(__fmaxl)
fldt 8(%rsp) // x
fldt 24(%rsp) // x : y
fucomi %st(0), %st
fcmovu %st(1), %st // now %st contains y if not NaN, x otherwise
fxch
fucomi %st(1), %st
jp 2f
fcmovb %st(1), %st
fstp %st(1)
ret
2: // Unordered.
fucomi %st(0), %st
jp 3f
// st(1) is a NaN; st(0) is not. Test if st(1) is signaling.
testb $0x40, 15(%rsp)
jz 4f
fstp %st(1)
ret
3: // st(0) is a NaN; st(1) may or may not be.
fxch
fucomi %st(0), %st
jp 4f
// st(1) is a NaN; st(0) is not. Test if st(1) is signaling.
testb $0x40, 31(%rsp)
jz 4f
fstp %st(1)
ret
4: // Both arguments are NaNs, or one is a signaling NaN.
faddp
ret
END(__fmaxl)
weak_alias (__fmaxl, fmaxl)

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@ -27,8 +27,25 @@ ENTRY(__fmin)
jmp 2f
1: ucomisd %xmm1, %xmm1 // Is xmm1 a NaN?
jp 2f // then return xmm0
jp 3f
// xmm0 is a NaN; xmm1 is not. Test if xmm0 is signaling.
movsd %xmm0, -8(%rsp)
testb $0x8, -2(%rsp)
jz 4f
movsd %xmm1, %xmm0 // otherwise return xmm1
ret
3: // xmm1 is a NaN; xmm0 may or may not be.
ucomisd %xmm0, %xmm0
jp 4f
// xmm1 is a NaN; xmm0 is not. Test if xmm1 is signaling.
movsd %xmm1, -8(%rsp)
testb $0x8, -2(%rsp)
jz 4f
ret
4: // Both arguments are NaNs, or one is a signaling NaN.
addsd %xmm1, %xmm0
2: ret
END(__fmin)

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@ -27,8 +27,25 @@ ENTRY(__fminf)
jmp 2f
1: ucomiss %xmm1, %xmm1 // Is xmm1 a NaN?
jp 2f // then return xmm0
jp 3f
// xmm0 is a NaN; xmm1 is not. Test if xmm0 is signaling.
movss %xmm0, -4(%rsp)
testb $0x40, -2(%rsp)
jz 4f
movss %xmm1, %xmm0 // otherwise return xmm1
ret
3: // xmm1 is a NaN; xmm0 may or may not be.
ucomiss %xmm0, %xmm0
jp 4f
// xmm1 is a NaN; xmm0 is not. Test if xmm1 is signaling.
movss %xmm1, -4(%rsp)
testb $0x40, -2(%rsp)
jz 4f
ret
4: // Both arguments are NaNs, or one is a signaling NaN.
addss %xmm1, %xmm0
2: ret
END(__fminf)

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@ -24,14 +24,35 @@ ENTRY(__fminl)
fldt 8(%rsp) // x
fldt 24(%rsp) // x : y
fucomi %st(0), %st
fcmovu %st(1), %st // now %st contains y if not NaN, x otherwise
fucomi %st(1), %st
jp 2f
fcmovnb %st(1), %st
fstp %st(1)
ret
2: // Unordered.
fucomi %st(0), %st
jp 3f
// st(1) is a NaN; st(0) is not. Test if st(1) is signaling.
testb $0x40, 15(%rsp)
jz 4f
fstp %st(1)
ret
3: // st(0) is a NaN; st(1) may or may not be.
fxch
fucomi %st(0), %st
jp 4f
// st(1) is a NaN; st(0) is not. Test if st(1) is signaling.
testb $0x40, 31(%rsp)
jz 4f
fstp %st(1)
ret
4: // Both arguments are NaNs, or one is a signaling NaN.
faddp
ret
END(__fminl)
weak_alias (__fminl, fminl)