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authorStefan Liebler <stli@linux.ibm.com>2019-12-11 15:09:20 +0100
committerStefan Liebler <stli@linux.ibm.com>2019-12-11 15:12:16 +0100
commita2a9b004297b777758420c952cb6eea5985d37fe (patch)
tree247d1784ddc3b3940b6e5439e19373d1c94fd930 /sysdeps/ieee754/dbl-64/s_rint.c
parentae3577f607b50bf3ce9b0877e43ad2508c9da61b (diff)
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Use GCC builtins for rint functions if desired.
This patch is using the corresponding GCC builtin for rintf, rint,
rintl and rintf128 if the USE_FUNCTION_BUILTIN macros are defined to one
in math-use-builtins.h.

This is the case for s390 if build with at least --march=z196 --mzarch.
Otherwise the generic implementation is used.  The code of the generic
implementation is not changed.

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Diffstat (limited to 'sysdeps/ieee754/dbl-64/s_rint.c')
-rw-r--r--sysdeps/ieee754/dbl-64/s_rint.c17
1 files changed, 11 insertions, 6 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_rint.c b/sysdeps/ieee754/dbl-64/s_rint.c
index 66c9196473..8604733ef9 100644
--- a/sysdeps/ieee754/dbl-64/s_rint.c
+++ b/sysdeps/ieee754/dbl-64/s_rint.c
@@ -23,16 +23,20 @@
 #include <math.h>
 #include <math_private.h>
 #include <libm-alias-double.h>
-
-static const double
-TWO52[2] = {
-	    4.50359962737049600000e+15, /* 0x43300000, 0x00000000 */
-	    -4.50359962737049600000e+15, /* 0xC3300000, 0x00000000 */
-};
+#include <math-use-builtins.h>
 
 double
 __rint (double x)
 {
+#if USE_RINT_BUILTIN
+  return __builtin_rint (x);
+#else
+  /* Use generic implementation.  */
+  static const double
+    TWO52[2] = {
+		4.50359962737049600000e+15, /* 0x43300000, 0x00000000 */
+		-4.50359962737049600000e+15, /* 0xC3300000, 0x00000000 */
+  };
   int64_t i0, sx;
   int32_t j0;
   EXTRACT_WORDS64 (i0, x);
@@ -59,6 +63,7 @@ __rint (double x)
     }
   double w = TWO52[sx] + x;
   return w - TWO52[sx];
+#endif /* ! USE_RINT_BUILTIN  */
 }
 #ifndef __rint
 libm_alias_double (__rint, rint)