Allow FP types for atomicrmw xchg

llvm-svn: 351427

1 files changed, 8 insertions, 7 deletions

diff --git a/llvm/docs/LangRef.rst b/llvm/docs/LangRef.rst
index 496a0f7eaaf..b28f2e6f8f6 100644
--- a/llvm/docs/LangRef.rst
+++ b/llvm/docs/LangRef.rst
@@ -8584,13 +8584,14 @@ operation. The operation must be one of the following keywords:
 -  umax
 -  umin
 
-The type of '<value>' must be an integer type whose bit width is a power
-of two greater than or equal to eight and less than or equal to a
-target-specific size limit. The type of the '``<pointer>``' operand must
-be a pointer to that type. If the ``atomicrmw`` is marked as
-``volatile``, then the optimizer is not allowed to modify the number or
-order of execution of this ``atomicrmw`` with other :ref:`volatile
-operations <volatile>`.
+For most of these operations, the type of '<value>' must be an integer
+type whose bit width is a power of two greater than or equal to eight
+and less than or equal to a target-specific size limit. For xchg, this
+may also be a floating point type with the same size constraints as
+integers. The type of the '``<pointer>``' operand must be a pointer to
+that type. If the ``atomicrmw`` is marked as ``volatile``, then the
+optimizer is not allowed to modify the number or order of execution of
+this ``atomicrmw`` with other :ref:`volatile operations <volatile>`.
 
 A ``atomicrmw`` instruction can also take an optional
 ":ref:`syncscope <syncscope>`" argument.