Issue 141215.4: Add DW_FORM_implicit_const form code
To allow the producer to represent certain enumeration-style
attributes as compactly as possible, we propose to add a new FORM
code, DW_FORM_implicit_const, that encodes a constant value
directly in the abbreviation declaration.
Proposed Changes to the Spec
----------------------------
In Section 7.5.3 ("Abbreviations Tables"), add the following
paragraph immediately following the paragraph beginning "Finally,
the child encoding is followed by a series of attribute
specifications":
The attribute form DW_FORM_implicit_const is a special case.
For attributes with this form, the attribute specification
contains a third part, which is a signed LEB128 number. The
value of this number is used as the value of the attribute,
and no value is stored in the .debug_info section.
In Section 7.5.4 ("Attribute Encodings"), for class "constant",
change "seven forms" to "eight forms", and add to the end of the
paragraph:
There is also a implicit constant (DW_FORM_implicit_const),
whose value is provided as part of the abbreviation
declaration.
Add the following row to Table 7.6 ("Attribute form encodings"):
Form name Value Classes
--------- ----- -------
DW_FORM_implicit_const xxx constant
--
2014/12/15 -- Replacement for 141003.1
2015/01/23 -- Accepted.
