Index: docs/LangRef.rst
===================================================================
--- docs/LangRef.rst
+++ docs/LangRef.rst
@@ -12258,8 +12258,8 @@
 The '``llvm.ctlz``' intrinsic counts the leading (most significant)
 zeros in a variable, or within each element of the vector. If
 ``src == 0`` then the result is the size in bits of the type of ``src``
-if ``is_zero_undef == 0`` and ``undef`` otherwise. For example,
-``llvm.ctlz(i32 2) = 30``.
+if ``is_zero_undef == 0`` and :ref:`poison value <poisonvalues>` otherwise.
+For example, ``llvm.ctlz(i32 2) = 30``.
 
 '``llvm.cttz.*``' Intrinsic
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -12305,8 +12305,8 @@
 The '``llvm.cttz``' intrinsic counts the trailing (least significant)
 zeros in a variable, or within each element of a vector. If ``src == 0``
 then the result is the size in bits of the type of ``src`` if
-``is_zero_undef == 0`` and ``undef`` otherwise. For example,
-``llvm.cttz(2) = 1``.
+``is_zero_undef == 0`` and :ref:`poison value <poisonvalues>` otherwise.
+For example, ``llvm.cttz(2) = 1``.
 
 .. _int_overflow: