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Diffstat (limited to 'gdb/doc/gdb.texinfo')
| -rw-r--r-- | gdb/doc/gdb.texinfo | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo index 808b675..da05dcc 100644 --- a/gdb/doc/gdb.texinfo +++ b/gdb/doc/gdb.texinfo @@ -9136,6 +9136,7 @@ gcc.info, Using the @sc{gnu} Compiler Collection (GCC)}. * C Checks:: C and C@t{++} type and range checks * Debugging C:: @value{GDBN} and C * Debugging C Plus Plus:: @value{GDBN} features for C@t{++} +* Decimal Floating Point:: Numbers in Decimal Floating Point format @end menu @node C Operators @@ -9604,6 +9605,28 @@ available choices, or to finish the type list for you. @xref{Completion,, Command Completion}, for details on how to do this. @end table +@node Decimal Floating Point +@subsubsection 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. @value{GDBN} will use the appropriate encoding for the configured +target. + +Because of a limitation in @file{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 ignores +underflow, overflow and divide by zero exceptions. + @node Objective-C @subsection Objective-C |