[PATCH v2 2/5] x86 long double: Support pseudo numbers in isnanl
Siddhesh Poyarekar
siddhesh@sourceware.org
Wed Dec 23 11:55:59 GMT 2020
This syncs up isnanl behaviour with gcc. Also move the isnanl
implementation to sysdeps/x86 and remove the sysdeps/x86_64 version.
---
sysdeps/{i386 => x86}/fpu/s_isnanl.c | 12 +++++++-----
sysdeps/x86_64/fpu/s_isnanl.c | 1 -
2 files changed, 7 insertions(+), 6 deletions(-)
rename sysdeps/{i386 => x86}/fpu/s_isnanl.c (76%)
delete mode 100644 sysdeps/x86_64/fpu/s_isnanl.c
diff --git a/sysdeps/i386/fpu/s_isnanl.c b/sysdeps/x86/fpu/s_isnanl.c
similarity index 76%
rename from sysdeps/i386/fpu/s_isnanl.c
rename to sysdeps/x86/fpu/s_isnanl.c
index fb97317bc9..45541df08a 100644
--- a/sysdeps/i386/fpu/s_isnanl.c
+++ b/sysdeps/x86/fpu/s_isnanl.c
@@ -28,16 +28,18 @@ static char rcsid[] = "$NetBSD: $";
int __isnanl(long double x)
{
- int32_t se,hx,lx;
+ int32_t se,hx,lx,pn;
GET_LDOUBLE_WORDS(se,hx,lx,x);
se = (se & 0x7fff) << 1;
- /* The additional & 0x7fffffff is required because Intel's
- extended format has the normally implicit 1 explicit
- present. Sigh! */
+ /* Detect pseudo-normal numbers, i.e. exponent is non-zero and the top
+ bit of the significand is not set. */
+ pn = (uint32_t)((~hx & 0x80000000) & (se|(-se)))>>31;
+ /* Clear the significand bit when computing mantissa. */
lx |= hx & 0x7fffffff;
se |= (uint32_t)(lx|(-lx))>>31;
se = 0xfffe - se;
- return (int)((uint32_t)(se))>>16;
+
+ return (int)(((uint32_t)(se)) >> 16) | pn;
}
hidden_def (__isnanl)
weak_alias (__isnanl, isnanl)
diff --git a/sysdeps/x86_64/fpu/s_isnanl.c b/sysdeps/x86_64/fpu/s_isnanl.c
deleted file mode 100644
index 06e69c3aeb..0000000000
--- a/sysdeps/x86_64/fpu/s_isnanl.c
+++ /dev/null
@@ -1 +0,0 @@
-#include <sysdeps/i386/fpu/s_isnanl.c>
--
2.29.2
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