[PATCH 2/4] alpha: fix floor on sNaN input

Aurelien Jarno aurelien@aurel32.net
Sun Jul 10 11:40:00 GMT 2016


The alpha version of floor wrongly return sNaN for sNaN input. Fix that
by checking for NaN and by returning the input value added with itself
in that case.

Finally remove the code to handle inexact exception, floor should never
generate such an exception.

Changelog:
	* sysdeps/alpha/fpu/s_floor.c (__floor): Add argument with itself
	when it is a NaN.
	[_IEEE_FP_INEXACT] Remove.
	* sysdeps/alpha/fpu/s_floorf.c (__floorf): Likewise.
---
 ChangeLog                    | 4 ++++
 sysdeps/alpha/fpu/s_floor.c  | 7 +++----
 sysdeps/alpha/fpu/s_floorf.c | 7 +++----
 3 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 681904f..5528047 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -4,6 +4,10 @@
 	when it is a NaN.
 	[_IEEE_FP_INEXACT] Remove.
 	* sysdeps/alpha/fpu/s_ceilf.c (__ceilf): Likewise.
+	* sysdeps/alpha/fpu/s_floor.c (__floor): Add argument with itself
+	when it is a NaN.
+	[_IEEE_FP_INEXACT] Remove.
+	* sysdeps/alpha/fpu/s_floorf.c (__floorf): Likewise.
 
 2016-07-08  Adhemerval Zanella  <adhemerval.zanella@linaro.org>
 
diff --git a/sysdeps/alpha/fpu/s_floor.c b/sysdeps/alpha/fpu/s_floor.c
index 1a6f8c4..9930f6b 100644
--- a/sysdeps/alpha/fpu/s_floor.c
+++ b/sysdeps/alpha/fpu/s_floor.c
@@ -27,16 +27,15 @@
 double
 __floor (double x)
 {
+  if (isnan (x))
+    return x + x;
+
   if (isless (fabs (x), 9007199254740992.0))	/* 1 << DBL_MANT_DIG */
     {
       double tmp1, new_x;
 
       __asm (
-#ifdef _IEEE_FP_INEXACT
-	     "cvttq/svim %2,%1\n\t"
-#else
 	     "cvttq/svm %2,%1\n\t"
-#endif
 	     "cvtqt/m %1,%0\n\t"
 	     : "=f"(new_x), "=&f"(tmp1)
 	     : "f"(x));
diff --git a/sysdeps/alpha/fpu/s_floorf.c b/sysdeps/alpha/fpu/s_floorf.c
index 8cd80e2..015c04f 100644
--- a/sysdeps/alpha/fpu/s_floorf.c
+++ b/sysdeps/alpha/fpu/s_floorf.c
@@ -26,6 +26,9 @@
 float
 __floorf (float x)
 {
+  if (isnanf (x))
+    return x + x;
+
   if (isless (fabsf (x), 16777216.0f))	/* 1 << FLT_MANT_DIG */
     {
       /* Note that Alpha S_Floating is stored in registers in a
@@ -36,11 +39,7 @@ __floorf (float x)
       float tmp1, tmp2, new_x;
 
       __asm ("cvtst/s %3,%2\n\t"
-#ifdef _IEEE_FP_INEXACT
-	     "cvttq/svim %2,%1\n\t"
-#else
 	     "cvttq/svm %2,%1\n\t"
-#endif
 	     "cvtqt/m %1,%0\n\t"
 	     : "=f"(new_x), "=&f"(tmp1), "=&f"(tmp2)
 	     : "f"(x));
-- 
2.8.1



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