This patch adds the ability for the ObjectYAML DWARFEmitter to calculate
the lengths of DIEs. This is accomplished by creating a DIEFixupVisitor
class which traverses the DWARF DIEs to calculate and fix up the lengths
in the Compile Unit header.
The DIEFixupVisitor can be extended in the future to enable more complex
fix ups which will enable simplified YAML string representations.
This is also very useful when using the YAML format in unit tests
because you no longer need to know the length of the compile unit when
writing the YAML string.
Differential commandeered from Chris Bieneman (beanz)
Differential revision: https://reviews.llvm.org/D30666
llvm-svn: 330421
Summary:
Original change was D43313 (r326932) and reverted by r326953 because it
broke an LLD test and a windows build. The LLD test was already fixed in
lld commit r326944 (thanks maskray). This is the original change with
the windows build fixed.
llvm-svn: 326970
This patch enhances DWARFDebugFrame with the capability of parsing and
printing DWARF expressions in CFI instructions. It also makes FDEs and
CIEs accessible to lib users, so they can process them in client tools
that rely on LLVM. To make it self-contained with a test case, it
teaches llvm-readobj to be able to dump EH frames and checks they are
correct in a unit test. The llvm-readobj code is Maksim Panchenko's work
(maksfb).
Reviewers: JDevlieghere, espindola
Reviewed By: JDevlieghere
Differential Revision: https://reviews.llvm.org/D43313
llvm-svn: 326932
Neither the linker nor the runtime need this information
anymore. We were originally using this to model BSS size
but the plan is now to use the segment metadata to allow
for BSS segments.
Differential Revision: https://reviews.llvm.org/D41366
llvm-svn: 326267
This is combination of two patches by Nicholas Wilson:
1. https://reviews.llvm.org/D41954
2. https://reviews.llvm.org/D42495
Along with a few local modifications:
- One change I made was to add the UNDEFINED bit to the binary format
to avoid the extra byte used when writing data symbols. Although this
bit is redundant for other symbols types (i.e. undefined can be
implied if a function or global is a wasm import)
- I prefer to be explicit and consistent and not have derived flags.
- Some field renaming.
- Some reverting of unrelated minor changes.
- No test output differences.
Differential Revision: https://reviews.llvm.org/D43147
llvm-svn: 325860
Introduce an extension to support passing linker options to the linker.
These would be ignored by older linkers, but newer linkers which support
this feature would be able to process the linker.
Emit a special discarded section `.linker-option`. The content of this
section is a pair of strings (key, value). The key is a type identifier for
the parameter. This allows for an argument free parameter that will be
processed by the linker with the value being the parameter. As an example,
`lib` identifies a library to be linked against, traditionally the `-l`
argument for Unix-based linkers with the parameter being the library name.
Thanks to James Henderson, Cary Coutant, Rafael Espinolda, Sean Silva
for the valuable discussion on the design of this feature.
llvm-svn: 323783
These indexes are useful because they are not always zero based and
functions and globals are referenced elsewhere by their index.
This matches what we already do for the type index space.
Differential Revision: https://reviews.llvm.org/D41877
llvm-svn: 322121
The problem was that our Obj -> Yaml dumper had not been taught
to handle certain types of records. This meant that when I
generated the test input files, the records were still there but
none of its fields were filled out. So when it did the
Yaml -> Obj conversion as part of the test, it generated records
with garbage in them.
The patch here fixes the Obj <-> Yaml converter, and additionally
updates the test file with fresh Yaml generated by the fixed
converter.
llvm-svn: 322029
This is the only wasm def (and likely likely will be
for the foreseeable) file so no need for a sub-directory
Differential Revision: https://reviews.llvm.org/D41476
llvm-svn: 321246
LLVM IR function names which disable mangling start with '\01'
(https://www.llvm.org/docs/LangRef.html#identifiers).
When an identifier like "\01@abc@" gets dumped to MIR, it is quoted, but
only with single quotes.
http://www.yaml.org/spec/1.2/spec.html#id2770814:
"The allowed character range explicitly excludes the C0 control block
allowed), the surrogate block #xD800-#xDFFF, #xFFFE, and #xFFFF."
http://www.yaml.org/spec/1.2/spec.html#id2776092:
"All non-printable characters must be escaped.
[...]
Note that escape sequences are only interpreted in double-quoted scalars."
This patch adds support for printing escaped non-printable characters
between double quotes if needed.
Should also fix PR31743.
Differential Revision: https://reviews.llvm.org/D41290
llvm-svn: 320996
Currently this is an LLVM extension to the COFF spec which is
experimental and intended to speed up linking. For now it is
behind a hidden cl::opt flag, but in the future we can move it
to a "real" cc1 flag and have the driver pass it through whenever
it is appropriate.
The patch to actually make use of this section in lld will come
in a followup.
Differential Revision: https://reviews.llvm.org/D40917
llvm-svn: 320649
The motivation behind this patch is that future directions require us to
be able to compute the hash value of records independently of actually
using them for de-duplication.
The current structure of TypeSerializer / TypeTableBuilder being a
single entry point that takes an unserialized type record, and then
hashes and de-duplicates it is not flexible enough to allow this.
At the same time, the existing TypeSerializer is already extremely
complex for this very reason -- it tries to be too many things. In
addition to serializing, hashing, and de-duplicating, ti also supports
splitting up field list records and adding continuations. All of this
functionality crammed into this one class makes it very complicated to
work with and hard to maintain.
To solve all of these problems, I've re-written everything from scratch
and split the functionality into separate pieces that can easily be
reused. The end result is that one class TypeSerializer is turned into 3
new classes SimpleTypeSerializer, ContinuationRecordBuilder, and
TypeTableBuilder, each of which in isolation is simple and
straightforward.
A quick summary of these new classes and their responsibilities are:
- SimpleTypeSerializer : Turns a non-FieldList leaf type into a series of
bytes. Does not do any hashing. Every time you call it, it will
re-serialize and return bytes again. The same instance can be re-used
over and over to avoid re-allocations, and in exchange for this
optimization the bytes returned by the serializer only live until the
caller attempts to serialize a new record.
- ContinuationRecordBuilder : Turns a FieldList-like record into a series
of fragments. Does not do any hashing. Like SimpleTypeSerializer,
returns references to privately owned bytes, so the storage is
invalidated as soon as the caller tries to re-use the instance. Works
equally well for LF_FIELDLIST as it does for LF_METHODLIST, solving a
long-standing theoretical limitation of the previous implementation.
- TypeTableBuilder : Accepts sequences of bytes that the user has already
serialized, and inserts them by de-duplicating with a hash table. For
the sake of convenience and efficiency, this class internally stores a
SimpleTypeSerializer so that it can accept unserialized records. The
same is not true of ContinuationRecordBuilder. The user is required to
create their own instance of ContinuationRecordBuilder.
Differential Revision: https://reviews.llvm.org/D40518
llvm-svn: 319198
Summary:
This change introduces a `DynamicSymbols` field to the ELF specific YAML
supported by `yaml2obj` and `obj2yaml`. This grouping of symbols provides a way
to represent ELF dynamic symbols. The `DynamicSymbols` structure is identical to
the existing `Symbols`.
Reviewers: compnerd, jakehehrlich, silvas
Reviewed By: silvas
Subscribers: silvas, jakehehrlich, llvm-commits
Differential Revision: https://reviews.llvm.org/D39582
llvm-svn: 318433
Summary:
This change allows yaml input to control the order of implicitly added sections
(`.symtab`, `.strtab`, `.shstrtab`). The order is controlled by adding a
placeholder section of the given name to the Sections field.
This change is to support changes in D39582, where it is desirable to control
the location of the `.dynsym` section.
This reapplied version fixes:
1. use of a function call within an assert
2. failing lld test which has an unnamed section
3. incorrect section count when given an unnamed section
Additionally, one more test to cover the unnamed section failure.
Reviewers: compnerd, jakehehrlich
Reviewed By: jakehehrlich
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39749
llvm-svn: 317789
Summary:
This change allows yaml input to control the order of implicitly added sections
(`.symtab`, `.strtab`, `.shstrtab`). The order is controlled by adding a
placeholder section of the given name to the Sections field.
This change is to support changes in D39582, where it is desirable to control
the location of the `.dynsym` section.
This reapplied version fixes:
1. use of a function call within an assert
2. failing lld test which has an unnamed section
Additionally, one more test to cover the unnamed section failure.
Reviewers: compnerd, jakehehrlich
Reviewed By: jakehehrlich
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39749
llvm-svn: 317646
Summary:
This change allows yaml input to control the order of implicitly added sections
(`.symtab`, `.strtab`, `.shstrtab`). The order is controlled by adding a
placeholder section of the given name to the Sections field.
This change is to support changes in D39582, where it is desirable to control
the location of the `.dynsym` section.
Reviewers: compnerd, jakehehrlich
Reviewed By: jakehehrlich
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39749
llvm-svn: 317622
Sometimes program headers have larger alignments than any of the
sections they contain. Currently yaml2obj can't produce such files. A
bug recently appeared in llvm-objcopy that failed in such a case. I'd
like to be able to add tests to llvm-objcopy for such cases.
This change adds an optional alignment parameter to program headers that
will be used instead of calculating the alignment.
Differential Revision: https://reviews.llvm.org/D39130
llvm-svn: 317139
This is in preparation for testing lld's upcoming relocation packing
feature (D39152). I have verified that this implementation correctly
unpacks the relocations from a Chromium DSO built with gold and the
Android relocation packer for ARM32 and ARM64.
Differential Revision: https://reviews.llvm.org/D39272
llvm-svn: 316543
This was previously being silently dropped by obj2yaml and caused
parsing errors with yaml2obj.
Differential Revision: https://reviews.llvm.org/D38490
llvm-svn: 314768
Add adds support for naming data segments. This is useful
useful linkers so that they can merge similar sections.
Differential Revision: https://reviews.llvm.org/D37886
llvm-svn: 313795
Add adds support for naming data segments. This is useful
useful linkers so that they can merge similar sections.
Differential Revision: https://reviews.llvm.org/D37886
llvm-svn: 313692
Right now Symbols must be either undefined or defined in a specific
section. Some symbols have section indexes like SHN_ABS however. This
change adds support for outputting symbols that have such section
indexes.
Patch by Jake Ehrlich
Differential Revision: https://reviews.llvm.org/D37391
llvm-svn: 312745
This change only treats imported and exports functions and globals
as symbol table entries the object has a "linking" section (i.e. it is
relocatable object file).
In this case all globals must be of type I32 and initialized with
i32.const. This was previously being assumed but not checked for and
was causing a failure on big endian machines due to using the wrong
value of then union.
See: https://bugs.llvm.org/show_bug.cgi?id=34487
Differential Revision: https://reviews.llvm.org/D37497
llvm-svn: 312674
Some kinds of relocations do not have symbols, like R_X86_64_RELATIVE
for instance. I would like to test this case in D36554 but currently
can't because symbols are required by yaml2obj. The other option is
using the empty symbol but that doesn't seem quite right to me.
This change makes the Symbol field of Relocation optional and in the
case where the user does not specify a symbol name the Symbol index is 0.
Patch by Jake Ehrlich
Differential Revision: https://reviews.llvm.org/D37276
llvm-svn: 312192
This change adds basic support for program headers.
I need to do some testing which requires generating program headers but
I can't use ld.lld or clang to produce programs that have headers. I'd
also like to test some strange things that those programs may never
produce.
Patch by Jake Ehrlich
Differential Revision: https://reviews.llvm.org/D35276
llvm-svn: 308520
Summary:
We were treating the GUIDs in TypeServer2Record as strings, and the
non-ASCII bytes in the GUID would not round-trip through YAML.
We already had the PDB_UniqueId type portably represent a Windows GUID,
but we need to hoist that up to the DebugInfo/CodeView library so that
we can use it in the TypeServer2Record as well as in PDB parsing code.
Reviewers: inglorion, amccarth
Subscribers: llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D35495
llvm-svn: 308234
Summary:
This allows tools like lld that process relocations
to apply data relocation correctly. This information
is required because relocation are stored as section
offset.
Subscribers: jfb, dschuff, jgravelle-google, aheejin
Differential Revision: https://reviews.llvm.org/D35234
llvm-svn: 307741
This is a short-term fix for PR33650 aimed to get the modules build bots green again.
Remove all the places where we use the LLVM_YAML_IS_(FLOW_)?SEQUENCE_VECTOR
macros to try to locally specialize a global template for a global type. That's
not how C++ works.
Instead, we now centrally define how to format vectors of fundamental types and
of string (std::string and StringRef). We use flow formatting for the former
cases, since that's the obvious right thing to do; in the latter case, it's
less clear what the right choice is, but flow formatting is really bad for some
cases (due to very long strings), so we pick block formatting. (Many of the
cases that were using flow formatting for strings are improved by this change.)
Other than the flow -> block formatting change for some vectors of strings,
this should result in no functionality change.
Differential Revision: https://reviews.llvm.org/D34907
Corresponding updates to clang, clang-tools-extra, and lld to follow.
llvm-svn: 306878
That may be useful if we want to produce or parse object containing
broken relocation values using yaml2obj/obj2yaml.
Previously that was impossible because only enum values were parsed
correctly, this patch allows to put any numeric value as a
relocation type.
Differential revision: https://reviews.llvm.org/D34758
llvm-svn: 306814
The overal size of the data section (including BSS)
is otherwise not included in the wasm binary.
Differential Revision: https://reviews.llvm.org/D34657
llvm-svn: 306459
Summary:
This fixes a bug where we always treat APSInts in Codeview as
signed when writing them to YAML. One symptom of this problem is that
llvm-pdbdump raw would show Enumerator Values that differ between the
original PDB and a PDB that has been round-tripped through YAML.
Reviewers: zturner
Reviewed By: zturner
Subscribers: llvm-commits, fhahn
Differential Revision: https://reviews.llvm.org/D34013
llvm-svn: 305965
We forgot to serialize these because llvm-readobj didn't dump them. They
are typically all zeros in an object file. The linker fills them in with
relocations before adding them to the PDB. Now we can properly round
trip these symbols through pdb2yaml -> yaml2pdb.
I made these fields optional with a zero default so that we can elide
them from our test cases.
llvm-svn: 305857
In the object file, the section index and relative offset are typically
zero, so make these YAML fields optional with a default.
It looks like there may be more partially initialized symbol records,
but this should fix the msan bot.
llvm-svn: 305842
This resubmits commit c0c249e9f2ef83e1d1e5f166b50673d92f3579d7.
It was broken due to some weird template issues, which have
since been fixed.
llvm-svn: 305517
This reverts commit 83ea17ebf2106859a51fbc2a86031b44d33696ad.
This is failing due to some strange template problems, so reverting
until it can be straightened out.
llvm-svn: 305505
After some internal discussions, we agreed that the raw output style had
outlived its usefulness. It was originally created before we had even
thought of dumping to YAML, and it was intended to give us some insight
into the internals of a PDB file. Now we have YAML mode which does
almost exactly this but is more powerful in that it can round-trip back
to a PDB, which the raw mode could not do. So the raw mode had become
purely a maintenance burden.
One option was to just delete it. However, its original goal was to be
as readable as possible while staying close to the "metal" - i.e.
presenting the output in a way that maps directly to the underlying file
format. We don't actually need that last requirement anymore since it's
covered by the yaml mode, so we could repurpose "raw" mode to actually
just be as readable as possible.
This patch implements about 80% of the functionality previously in raw
mode, but in a completely different style that is more akin to what
cvdump outputs. Records are very compressed, often times appearing on
just one line. One nice thing about this is that it makes full record
matching easier, because you can grep for indices, names, and leaf types
on a single line often.
See the tests for some examples of what the new output looks like.
Note that this patch actually regresses the functionality of raw mode in
a few areas, but only because the patch was already unreasonably large
and going 100% would have been even worse. Specifically, this patch is
missing:
The ability to dump module debug subsections (checksums, lines, etc)
The ability to dump section headers
Aside from that everything is here. While goign through the tests fixing
them all up, I found many duplicate tests. They've been deleted. In
subsequent patches I will go through and re-add the missing
functionality.
Differential Revision: https://reviews.llvm.org/D34191
llvm-svn: 305495
This was originally reverted because of some non-deterministic
failures on certain buildbots. Luckily ASAN eventually caught
this as a stack-use-after-scope, so the fix is included in
this patch.
llvm-svn: 305393
This is causing failures on linux bots with an invalid stream
read. It doesn't repro in any configuration on Windows, so
reverting until I have a chance to investigate on Linux.
llvm-svn: 305371
This allows us to use yaml2obj and obj2yaml to round-trip CodeView
symbol and type information without having to manually specify the bytes
of the section. This makes for much easier to maintain tests. See the
tests under lld/COFF in this patch for example. Before they just said
SectionData: <blob> whereas now we can use meaningful record
descriptions. Note that it still supports the SectionData yaml field,
which could be useful for initializing a section to invalid bytes for
testing, for example.
Differential Revision: https://reviews.llvm.org/D34127
llvm-svn: 305366
When we get an unknown symbol type, we might as well at least
dump it. Same goes for round-tripping through YAML, we can
dump the record contents as raw bytes even if we don't know
how to interpret it semantically.
llvm-svn: 305248
This adds support for Symbols, StringTable, and FrameData subsection
types. Even though these subsections rarely if ever appear in a PDB
file (they are usually in object files), there's no theoretical reason
why they *couldn't* appear in a PDB. The real issue though is that in
order to add support for dumping and writing them (which will be useful
for object files), we need a way to test them. And since there is no
support for reading and writing them to / from object files yet, making
PDB support them is the best way to both add support for the underlying
format and add support for tests at the same time. Later, when we go
to add support for reading / writing them from object files, we'll need
only minimal changes in the underlying read/write code.
llvm-svn: 305037
This is the same change for the YAML Output style applied to the
raw output style. Previously we would queue up all subsections
until every one had been read, and then output them in a pre-
determined order. This was because some subsections need to be
read first in order to properly dump later subsections. This
patch allows them to be dumped in the order they appear.
Differential Revision: https://reviews.llvm.org/D34015
llvm-svn: 305034
This creates a new library called BinaryFormat that has all of
the headers from llvm/Support containing structure and layout
definitions for various types of binary formats like dwarf, coff,
elf, etc as well as the code for identifying a file from its
magic.
Differential Revision: https://reviews.llvm.org/D33843
llvm-svn: 304864
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.
I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.
This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.
Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).
llvm-svn: 304787
While it's not entirely clear why a compiler or linker might
put this information into an object or PDB file, one has been
spotted in the wild which was causing llvm-pdbdump to crash.
This patch adds support for reading-writing these sections.
Since I don't know how to get one of the native tools to
generate this kind of debug info, the only test here is one
in which we feed YAML into the tool to produce a PDB and
then spit out YAML from the resulting PDB and make sure that
it matches.
llvm-svn: 304738
Previously we would expect certain subsections to appear
in a certain order because some subsections would reference
other subsections, but in practice we need to support
arbitrary orderings since some object file and PDB file
producers generate them this way. This also paves the
way for supporting Yaml <-> Object File conversion of
CodeView, since Object Files typically have quite a
large number of subsections in their debug info.
Differential Revision: https://reviews.llvm.org/D33807
llvm-svn: 304588
Object files have symbol records not aligned to any particular
boundary (e.g. 1-byte aligned), while PDB files have symbol
records padded to 4-byte aligned boundaries. Since they share
the same reading / writing code, we have to provide an option to
specify the alignment and propagate it up to the producer or
consumer who knows what the alignment is supposed to be for the
given container type.
Added a test for this by modifying the existing PDB -> YAML -> PDB
round-tripping code to round trip symbol records as well as types.
Differential Revision: https://reviews.llvm.org/D33785
llvm-svn: 304484
The code was a mess and disorganized due to the sheer amount
of it being in one file. So I'm splitting this into three files.
One for CodeView types, one for CodeView symbols, and one for
CodeView debug subsections. NFC.
llvm-svn: 304278
CodeViewYAML.h attempts to hide the details of many of the
CodeView yaml structures and types, but at the same time it
exposes the mapping traits for them to external users of the
header.
This patch just hides these in the implementation files so that
the interface is kept as simple as possible.
llvm-svn: 304263
This continues the effort to get the CodeView YAML parsing logic
into ObjectYAML. After this patch, the only missing piece will
be the CodeView debug symbol subsections.
llvm-svn: 304256
This is the beginning of an effort to move the codeview yaml
reader / writer into ObjectYAML so that it can be shared.
Currently the only consumer / producer of CodeView YAML is
llvm-pdbdump, but CodeView can exist outside of PDB files, and
indeed is put into object files and passed to the linker to
produce PDB files. Furthermore, there are subtle differences
in the types of records that show up in object file CodeView
vs PDB file CodeView, but they are otherwise 99% the same.
By having this code in ObjectYAML, we can have llvm-pdbdump
reuse this code, while teaching obj2yaml and yaml2obj to use
this syntax for dealing with object files that can contain
CodeView.
This patch only adds support for CodeView type information
to ObjectYAML. Subsequent patches will add support for
CodeView symbol information.
llvm-svn: 304248
This warning didn't show up on my local build
but is causing the bots to fail. Seems like a
bad idea to have types and variables with the
same name anyhow.
Differential Revision: https://reviews.llvm.org/D33022
llvm-svn: 302606
Previously we had only supported the importing and
exporting of functions and globals.
Also, add usefull overload of getWasmSymbol() and
getNumberOfSymbols() in support of lld port.
Differential Revision: https://reviews.llvm.org/D33011
llvm-svn: 302601
Summary:
Addends are used as offsets to addresses of globals
and can be both positive and negative. This change
prints libObject in line with the spec and the MC
layer.
Subscribers: jfb, dschuff
Differential Revision: https://reviews.llvm.org/D32507
llvm-svn: 301369
Mostly this change adds support converting to and from
YAML which will allow us to write more test cases for
the WebAssembly MC and lld ports.
Better support for objdump, readelf, and nm will be in
followup CLs.
I had to update the two wasm test binaries because they
used the old style 'name' section which is no longer
supported.
Differential Revision: https://reviews.llvm.org/D31099
Patch by Sam Clegg
llvm-svn: 299101
In my refactoring I introduced a bug where we were using the reference size instead of the offset size for DW_FORM_strp and similar forms.
This patch resolves the error and adds a test case testing all the DWARF forms for DWARF2 AddrSize 8. There is similar coverage already in the DWARFDebugInfoTest sources that covers the parser. Once I migrate the DWARFGenerator APIs to be built on the YAML tools they will be fully covered under the same tests.
llvm-svn: 297230
This patch adds support to the DWARF YAML reader and writer for the new DWARF5 abbreviation form, DW_FORM_implicit_const.
The attribute was added in r291599.
llvm-svn: 297091
Some late additions to DWARF v5 were not in Dwarf.def; also one form
was redefined. Add the new cases to relevant switches in different
parts of LLVM. Replace DW_FORM_ref_sup with DW_FORM_ref_sup[4,8].
I did not add support for DW_FORM_strx3/addrx3 other that defining the
constants. We don't have any infrastructure to support these.
Differential Revision: http://reviews.llvm.org/D30664
llvm-svn: 297085
Summary: This patch refactors the DWARFYAML code for dumping compile units to use a visitor pattern. Using this design will, in the future, enable the DWARF YAML code to perform analysis and mutations of the DWARF DIEs. An example of such mutations would be calculating the length of a compile unit and updating the CU's Length field before writing the DIE. This support will make it easier to craft or modify DWARF tests by hand.
Reviewers: lhames
Subscribers: mgorny, fhahn, jgosnell, aprantl, llvm-commits
Differential Revision: https://reviews.llvm.org/D30357
llvm-svn: 297067
In the DWARF 4 Spec section 7.2.2, data in many DWARF sections, and some DWARF structures start with "Initial Length Values", which are a 32-bit length, and an optional 64-bit length if the 32 bit value == UINT32_MAX.
This patch abstracts the Initial Length type in YAML, and extends its use to all the DWARF structures that are supported in the DWARFYAML code that have Initial Length values.
llvm-svn: 296911
Matt Arsenault