builtins: Add __builtin_nextafterf16b builtin

The following patch adds another needed builtin.
The earlier patch adds among other things __builtin_nextafterf16
builtin which we need in order to constexpr evaluate
std::nextafter(_Float16) overload (patch for that has been posted already).
While there is inline implementation of the overload, it isn't constant
evaluation friendly, and the builtin doesn't need libm implementation
because it will be used only during constant expression evaluation.
We need the same thing also for std::nextafter(__gnu_cxx::__bfloat16_t)
though and this patch does that.

2022-10-31  Jakub Jelinek  <jakub@redhat.com>

	* builtin-types.def (BT_FN_BFLOAT16_BFLOAT16_BFLOAT16): New.
	* builtins.def (BUILT_IN_NEXTAFTERF16B): New builtin.
	* fold-const-call.cc (fold_const_call_sss): Handle
	CFN_BUILT_IN_NEXTAFTERF16B.

diff --git a/gcc/builtin-types.def b/gcc/builtin-types.def
index 2dbed8ae05cedacabeafecc25f9d564764586a09..81460e1ed2b596d10eea4f82bbf1547e8452f89b 100644 (file)
--- a/gcc/builtin-types.def
+++ b/gcc/builtin-types.def
@@ -461,6 +461,8 @@ DEF_FUNCTION_TYPE_2 (BT_FN_FLOAT64X_FLOAT64X_FLOAT64X,
                     BT_FLOAT64X, BT_FLOAT64X, BT_FLOAT64X)
 DEF_FUNCTION_TYPE_2 (BT_FN_FLOAT128X_FLOAT128X_FLOAT128X,
                     BT_FLOAT128X, BT_FLOAT128X, BT_FLOAT128X)
+DEF_FUNCTION_TYPE_2 (BT_FN_BFLOAT16_BFLOAT16_BFLOAT16,
+                    BT_BFLOAT16, BT_BFLOAT16, BT_BFLOAT16)
 DEF_FUNCTION_TYPE_2 (BT_FN_FLOAT_FLOAT_FLOATPTR,
                     BT_FLOAT, BT_FLOAT, BT_FLOAT_PTR)
 DEF_FUNCTION_TYPE_2 (BT_FN_DOUBLE_DOUBLE_DOUBLEPTR,

diff --git a/gcc/builtins.def b/gcc/builtins.def
index 42c005a7651c057fb074bf1cd49b4072dbee0111..49973151bfe4d4fc4268823ed1d50a6cbd1755ba 100644 (file)
--- a/gcc/builtins.def
+++ b/gcc/builtins.def
@@ -591,6 +591,7 @@ DEF_C99_BUILTIN        (BUILT_IN_NEXTAFTERF, "nextafterf", BT_FN_FLOAT_FLOAT_FLO
 DEF_C99_BUILTIN        (BUILT_IN_NEXTAFTERL, "nextafterl", BT_FN_LONGDOUBLE_LONGDOUBLE_LONGDOUBLE, ATTR_MATHFN_ERRNO)
 #define NEXTAFTER_TYPE(F) BT_FN_##F##_##F##_##F
 DEF_EXT_LIB_FLOATN_NX_BUILTINS (BUILT_IN_NEXTAFTER, "nextafter", NEXTAFTER_TYPE, ATTR_MATHFN_ERRNO)
+DEF_GCC_BUILTIN        (BUILT_IN_NEXTAFTERF16B, "nextafterf16b", BT_FN_BFLOAT16_BFLOAT16_BFLOAT16, ATTR_MATHFN_ERRNO)
 DEF_C99_BUILTIN        (BUILT_IN_NEXTTOWARD, "nexttoward", BT_FN_DOUBLE_DOUBLE_LONGDOUBLE, ATTR_MATHFN_ERRNO)
 DEF_C99_BUILTIN        (BUILT_IN_NEXTTOWARDF, "nexttowardf", BT_FN_FLOAT_FLOAT_LONGDOUBLE, ATTR_MATHFN_ERRNO)
 DEF_C99_BUILTIN        (BUILT_IN_NEXTTOWARDL, "nexttowardl", BT_FN_LONGDOUBLE_LONGDOUBLE_LONGDOUBLE, ATTR_MATHFN_ERRNO)

diff --git a/gcc/fold-const-call.cc b/gcc/fold-const-call.cc
index 5f158152807e50fc117e2763493d729ee66e1009..ab1b098d6ca2acc747a1ea91bb08c8a7aee8a4d3 100644 (file)
--- a/gcc/fold-const-call.cc
+++ b/gcc/fold-const-call.cc
@@ -1438,6 +1438,7 @@ fold_const_call_sss (real_value *result, combined_fn fn,
 
     CASE_CFN_NEXTAFTER:
     CASE_CFN_NEXTAFTER_FN:
+    case CFN_BUILT_IN_NEXTAFTERF16B:
     CASE_CFN_NEXTTOWARD:
       return fold_const_nextafter (result, arg0, arg1, format);