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This patch aims to add necessary description for __builtin_flt_rounds and
__builtins_set_flt_rounds in LanguageExtensions.rst
Repository:
rG LLVM Github Monorepo
https://reviews.llvm.org/D146188
Files:
clang/docs/LanguageExtensions.rst
Index: clang/docs/LanguageExtensions.rst
===================================================================
--- clang/docs/LanguageExtensions.rst
+++ clang/docs/LanguageExtensions.rst
@@ -3246,7 +3246,7 @@
double __builtin_canonicalize(double);
float __builtin_canonicalizef(float);
- long double__builtin_canonicalizel(long double);
+ long double __builtin_canonicalizel(long double);
Returns the platform specific canonical encoding of a floating point
number. This canonicalization is useful for implementing certain
@@ -3254,6 +3254,46 @@
<https://llvm.org/docs/LangRef.html#llvm-canonicalize-intrinsic>`_ for
more information on the semantics.
+``__builtin_flt_rounds``
+--------------------------
+
+.. code-block:: c
+
+ int __builtin_flt_rounds();
+
+Returns the current rounding mode. Encoding of the returned values is
+same as the result of FLT_ROUNDS, specified by C standard:
+0 - toward zero
+1 - to nearest, ties to even
+2 - toward positive infinity
+3 - toward negative infinity
+4 - to nearest, ties away from zero
+See `llvm.get.rounding
+<https://llvm.org/docs/LangRef.html#llvm-get-rounding-intrinsic>`_ for
+more information on the semantics.
+
+``__builtin_set_flt_rounds``
+--------------------------
+
+.. code-block:: c
+
+ void __builtin_set_flt_rounds(int);
+
+Sets the current rounding mode. Encoding of the returned values is
+same as the result of FLT_ROUNDS, specified by C standard:
+0 - toward zero
+1 - to nearest, ties to even
+2 - toward positive infinity
+3 - toward negative infinity
+4 - to nearest, ties away from zero
+See `llvm.set.rounding
+<https://llvm.org/docs/LangRef.html#llvm-set-rounding-intrinsic>`_ for
+more information on the semantics.
+This builtin is converted to llvm.set.rounding intrinsic in LLVM IR level
+and not all targets support this intrinsic, so only x86 and arm targets
+support this builtin. Since this builtin changes default floating-point
+environment, ``#pragma STDC FENV_ACCESS ON`` is required.
+
String builtins
---------------
Index: clang/docs/LanguageExtensions.rst
===================================================================
--- clang/docs/LanguageExtensions.rst
+++ clang/docs/LanguageExtensions.rst
@@ -3246,7 +3246,7 @@
double __builtin_canonicalize(double);
float __builtin_canonicalizef(float);
- long double__builtin_canonicalizel(long double);
+ long double __builtin_canonicalizel(long double);
Returns the platform specific canonical encoding of a floating point
number. This canonicalization is useful for implementing certain
@@ -3254,6 +3254,46 @@
<https://llvm.org/docs/LangRef.html#llvm-canonicalize-intrinsic>`_ for
more information on the semantics.
+``__builtin_flt_rounds``
+--------------------------
+
+.. code-block:: c
+
+ int __builtin_flt_rounds();
+
+Returns the current rounding mode. Encoding of the returned values is
+same as the result of FLT_ROUNDS, specified by C standard:
+0 - toward zero
+1 - to nearest, ties to even
+2 - toward positive infinity
+3 - toward negative infinity
+4 - to nearest, ties away from zero
+See `llvm.get.rounding
+<https://llvm.org/docs/LangRef.html#llvm-get-rounding-intrinsic>`_ for
+more information on the semantics.
+
+``__builtin_set_flt_rounds``
+--------------------------
+
+.. code-block:: c
+
+ void __builtin_set_flt_rounds(int);
+
+Sets the current rounding mode. Encoding of the returned values is
+same as the result of FLT_ROUNDS, specified by C standard:
+0 - toward zero
+1 - to nearest, ties to even
+2 - toward positive infinity
+3 - toward negative infinity
+4 - to nearest, ties away from zero
+See `llvm.set.rounding
+<https://llvm.org/docs/LangRef.html#llvm-set-rounding-intrinsic>`_ for
+more information on the semantics.
+This builtin is converted to llvm.set.rounding intrinsic in LLVM IR level
+and not all targets support this intrinsic, so only x86 and arm targets
+support this builtin. Since this builtin changes default floating-point
+environment, ``#pragma STDC FENV_ACCESS ON`` is required.
+
String builtins
---------------
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