[PATCH] gas/doc: improve AVR modifiers wording.

* doc/c-avr.texi: Improve wording.

gas/ChangeLog

@@ -1,3 +1,7 @@
+2020-06-09  Seth Girvan  <snth@snthhacks.com>
+
+	* doc/c-avr.texi: Improve wording.
+
 2020-06-09  Jan Beulich  <jbeulich@suse.com>
 
 	* testsuite/gas/i386/x86-64-pseudos-bad.s,

gas/doc/c-avr.texi

@@ -230,12 +230,12 @@ modifier(relocatable-expression)
 @item lo8
 
 This modifier allows you to use bits 0 through 7 of
-an address expression as 8 bit relocatable expression.
+an address expression as an 8 bit relocatable expression.
 
 @item hi8
 
 This modifier allows you to use bits 7 through 15 of an address expression
-as 8 bit relocatable expression.  This is useful with, for example, the
+as an 8 bit relocatable expression. This is useful with, for example, the
 AVR @samp{ldi} instruction and @samp{lo8} modifier.
 
 For example
@@ -248,7 +248,7 @@ ldi r27, hi8(sym+10)
 @item hh8
 
 This modifier allows you to use bits 16 through 23 of
-an address expression as 8 bit relocatable expression.
+an address expression as an 8 bit relocatable expression.
 Also, can be useful for loading 32 bit constants.
 
 @item hlo8
@@ -258,7 +258,7 @@ Synonym of @samp{hh8}.
 @item hhi8
 
 This modifier allows you to use bits 24 through 31 of
-an expression as 8 bit expression. This is useful with, for example, the
+an expression as an 8 bit expression. This is useful with, for example, the
 AVR @samp{ldi} instruction and @samp{lo8}, @samp{hi8}, @samp{hlo8},
 @samp{hhi8}, modifier.
 
@@ -275,24 +275,33 @@ ldi r29, hhi8(285774925)
 @item pm_lo8
 
 This modifier allows you to use bits 0 through 7 of
-an address expression as 8 bit relocatable expression.
-This modifier useful for addressing data or code from
-Flash/Program memory. The using of @samp{pm_lo8} similar
-to @samp{lo8}.
+an address expression as an 8 bit relocatable expression.
+This modifier is useful for addressing data or code from
+Flash/Program memory by two-byte words. The use of @samp{pm_lo8}
+is similar to @samp{lo8}.
 
 @item pm_hi8
 
 This modifier allows you to use bits 8 through 15 of
-an address expression as 8 bit relocatable expression.
-This modifier useful for addressing data or code from
-Flash/Program memory.
+an address expression as an 8 bit relocatable expression.
+This modifier is useful for addressing data or code from
+Flash/Program memory by two-byte words.
+
+For example, when setting the AVR @samp{Z} register with the @samp{ldi}
+instruction for subsequent use by the @samp{ijmp} instruction:
+
+@smallexample
+ldi r30, pm_lo8(sym)
+ldi r31, pm_hi8(sym)
+ijmp
+@end smallexample
 
 @item pm_hh8
 
 This modifier allows you to use bits 15 through 23 of
-an address expression as 8 bit relocatable expression.
-This modifier useful for addressing data or code from
-Flash/Program memory.
+an address expression as an 8 bit relocatable expression.
+This modifier is useful for addressing data or code from
+Flash/Program memory by two-byte words.
 
 @end table