2007-12-28  Thiago Jung Bauermann  <bauerman@br.ibm.com>

	* gdb.texinfo (Examining Data): Add Decimal Floating Point format
	subsection.
	(Decimal Floating Point format): New subsection.

Index: src-git/gdb/doc/gdb.texinfo
===================================================================
--- src-git.orig/gdb/doc/gdb.texinfo	2007-12-28 01:11:37.000000000 -0200
+++ src-git/gdb/doc/gdb.texinfo	2007-12-28 02:16:56.000000000 -0200
@@ -5494,6 +5494,7 @@ Table}.
 * Character Sets::              Debugging programs that use a different
                                 character set than GDB does
 * Caching Remote Data::         Data caching for remote targets
+* Decimal Floating Point::      Numbers in Decimal Floating Point format
 @end menu
 
 @node Expressions
@@ -7473,6 +7474,28 @@ the data cache operation.
 @end table
 
 
+@node Decimal Floating Point
+@section Decimal Floating Point format
+@cindex decimal floating point format
+
+@value{GDBN} can examine, set and perform computations with numbers in
+decimal floating point format, which in the C language correspond to the
+@code{_Decimal32}, @code{_Decimal64} and @code{_Decimal128} types as
+specified by the extension to support decimal floating-point arithmetic.
+
+There are two encodings in use, depending on the architecture: BID (Binary
+Integer Decimal) for x86 and x86-64, and DPD (Densely Packed Decimal) for
+PowerPC. GDB will use the appropriate encoding for the configured target.
+
+Because of a limitation in libdecnumber, the library used by @value{GDBN}
+to manipulate decimal floating point numbers, it is not possible to convert
+(using a cast, for example) integers wider than 32-bit to decimal float.
+
+In addition, in order to imitate @value{GDBN}'s behaviour with binary floating
+point computations, error checking in decimal float operations ignore underflow,
+overflow and divide by zero exceptions.
+
+
 @node Macros
 @chapter C Preprocessor Macros