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authorXiaolin Tang <tangxiaolin@loongson.cn>2022-11-23 11:45:00 +0800
committercaiyinyu <caiyinyu@loongson.cn>2022-11-29 16:00:28 +0800
commit2e2485ce05bce85bf092ba0752854afa14b92dad (patch)
tree4138377bc399d8368b1e838941f12889ff4c8495 /sysdeps/ieee754
parentf711e4ef53990b6c76f2dfdbcb9f791c541cdac3 (diff)
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Use GCC builtins for logb functions if desired.
This patch is using the corresponding GCC builtin for logbf, logb,
logbl and logbf128 if the USE_FUNCTION_BUILTIN macros are defined to one
in math-use-builtins-function.h.

Co-Authored-By: Xi Ruoyao <xry111@xry111.site>
Diffstat (limited to 'sysdeps/ieee754')
-rw-r--r--sysdeps/ieee754/dbl-64/s_logb.c5
-rw-r--r--sysdeps/ieee754/float128/float128_private.h2
-rw-r--r--sysdeps/ieee754/flt-32/s_logbf.c5
-rw-r--r--sysdeps/ieee754/ldbl-128/s_logbl.c6
4 files changed, 18 insertions, 0 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_logb.c b/sysdeps/ieee754/dbl-64/s_logb.c
index 82cabd206a..dd74d5f08c 100644
--- a/sysdeps/ieee754/dbl-64/s_logb.c
+++ b/sysdeps/ieee754/dbl-64/s_logb.c
@@ -21,10 +21,14 @@
 #include <math_private.h>
 #include <libm-alias-double.h>
 #include <fix-int-fp-convert-zero.h>
+#include <math-use-builtins.h>
 
 double
 __logb (double x)
 {
+#if USE_LOGB_BUILTIN
+  return __builtin_logb (x);
+#else
   int64_t ix, ex;
 
   EXTRACT_WORDS64 (ix, x);
@@ -42,6 +46,7 @@ __logb (double x)
   if (FIX_INT_FP_CONVERT_ZERO && ex == 1023)
     return 0.0;
   return (double) (ex - 1023);
+#endif /* !USE_LOGB_BUILTIN  */
 }
 #ifndef __logb
 libm_alias_double (__logb, logb)
diff --git a/sysdeps/ieee754/float128/float128_private.h b/sysdeps/ieee754/float128/float128_private.h
index 3bb5fffa74..78107b1525 100644
--- a/sysdeps/ieee754/float128/float128_private.h
+++ b/sysdeps/ieee754/float128/float128_private.h
@@ -165,6 +165,8 @@
 #define USE_LRINTL_BUILTIN USE_LRINTF128_BUILTIN
 #undef USE_LLRINTL_BUILTIN
 #define USE_LLRINTL_BUILTIN USE_LLRINTF128_BUILTIN
+#undef USE_LOGBL_BUILTIN
+#define USE_LOGBL_BUILTIN USE_LOGBF128_BUILTIN
 
 /* IEEE function renames.  */
 #define __ieee754_acoshl __ieee754_acoshf128
diff --git a/sysdeps/ieee754/flt-32/s_logbf.c b/sysdeps/ieee754/flt-32/s_logbf.c
index a06f975797..b027e7b9c2 100644
--- a/sysdeps/ieee754/flt-32/s_logbf.c
+++ b/sysdeps/ieee754/flt-32/s_logbf.c
@@ -16,10 +16,14 @@
 #include <math_private.h>
 #include <libm-alias-float.h>
 #include <fix-int-fp-convert-zero.h>
+#include <math-use-builtins.h>
 
 float
 __logbf (float x)
 {
+#if USE_LOGBF_BUILTIN
+  return __builtin_logbf (x);
+#else
   int32_t ix, rix;
 
   GET_FLOAT_WORD (ix, x);
@@ -37,5 +41,6 @@ __logbf (float x)
   if (FIX_INT_FP_CONVERT_ZERO && rix == 127)
     return 0.0f;
   return (float) (rix - 127);
+#endif /* ! USE_LOGBF_BUILTIN */
 }
 libm_alias_float (__logb, logb)
diff --git a/sysdeps/ieee754/ldbl-128/s_logbl.c b/sysdeps/ieee754/ldbl-128/s_logbl.c
index 1c56eda499..59b08aa295 100644
--- a/sysdeps/ieee754/ldbl-128/s_logbl.c
+++ b/sysdeps/ieee754/ldbl-128/s_logbl.c
@@ -25,10 +25,15 @@ static char rcsid[] = "$NetBSD: $";
 #include <math.h>
 #include <math_private.h>
 #include <libm-alias-ldouble.h>
+#include <math-use-builtins.h>
 
 _Float128
 __logbl (_Float128 x)
 {
+#if USE_LOGBL_BUILTIN
+  return __builtin_logbl (x);
+#else
+  /* Use generic implementation.  */
   int64_t lx, hx, ex;
 
   GET_LDOUBLE_WORDS64 (hx, lx, x);
@@ -49,6 +54,7 @@ __logbl (_Float128 x)
       ex -= ma - 16;
     }
   return (_Float128) (ex - 16383);
+#endif /* ! USE_LOGBL_BUILTIN  */
 }
 
 libm_alias_ldouble (__logb, logb)