[llvm] Proofread BackGuide.rst (#151281)

Author: kazutakahirata

llvm/docs/TableGen/BackGuide.rst

@@ -191,7 +191,7 @@ Some of these classes have additional members that
 are described in the following subsections.
 
 *All* of the classes derived from ``RecTy`` provide the ``get()`` function.
-It returns an instance of ``Recty`` corresponding to the derived class.
+It returns an instance of ``RecTy`` corresponding to the derived class.
 Some of the ``get()`` functions require an argument to
 specify which particular variant of the type is desired. These arguments are
 described in the following subsections.
@@ -354,12 +354,12 @@ The class provides many additional functions:
 * Functions to determine whether there are any operands and to get the
   number of operands.
 
-* Functions to the get the operands, both individually and together.
+* Functions to get the operands, both individually and together.
 
 * Functions to determine whether there are any names and to
   get the number of names
 
-* Functions to the get the names, both individually and together.
+* Functions to get the names, both individually and together.
 
 * Functions to get the operand iterator ``begin()`` and ``end()`` values.
 
@@ -605,7 +605,7 @@ null if the field does not exist.
 
 The field is assumed to have another record as its value. That record is returned
 as a pointer to a ``Record``. If the field does not exist or is unset, the
-functions returns null.
+function returns null.
 
 Getting Record Superclasses
 ===========================