By taking a reference we can do the ownership transfer in one place instead of
expecting every caller to do it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216492 91177308-0d34-0410-b5e6-96231b3b80d8
The attached patch simplifies a few interfaces that don't need to take
ownership of a buffer.
For example, both parseAssembly and parseBitcodeFile will parse the
entire buffer before returning. There is no need to take ownership.
Using a MemoryBufferRef makes it obvious in the type signature that
there is no ownership transfer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216488 91177308-0d34-0410-b5e6-96231b3b80d8
Long term the idea if for the engine to not own the buffers, but for now
this is consistent with the rest of the API.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216484 91177308-0d34-0410-b5e6-96231b3b80d8
The memory management in BugPoint is fairly convoluted, so this just unwraps
one layer by changing the return type of functions that always return
owned Modules.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216464 91177308-0d34-0410-b5e6-96231b3b80d8
Take a StringRef instead of a "const char *".
Take a "std::error_code &" instead of a "std::string &" for error.
A create static method would be even better, but this patch is already a bit too
big.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216393 91177308-0d34-0410-b5e6-96231b3b80d8
The switch statement would never fire due to the preceding break statement. Also, the switch statement has a default label with no case labels. Simplified the code, and allow it to execute.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216346 91177308-0d34-0410-b5e6-96231b3b80d8
There are two parts to this. First, the plugin needs to tell gold the comdat by
setting comdat_key.
What gets things a bit more complicated is that gold only seems
symbols. In particular, if A is an alias to B, it only sees the symbols
A and B. It can then ask us to keep symbol A but drop symbol B. What
we have to do instead is to create an internal version of B and make A
an alias to that.
At some point some of this logic should be moved to lib/Linker so that
we don't map a Constant to an internal version just to have lib/Linker
map that again to the destination module.
The reason for implementing this in tools/gold for now is simplicity.
With it in place it should be possible to update clang to use comdats
for constructors and destructors on ELF without breaking the LTO
bootstrap. Once that is done I intend to come back and improve the
interface lib/Linker exposes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216302 91177308-0d34-0410-b5e6-96231b3b80d8
This commit expands llvm-cov's functionality by adding support for a new code coverage
tool that uses LLVM's coverage mapping format and clang's instrumentation based profiling.
The gcov compatible tool can be invoked by supplying the 'gcov' command as the first argument,
or by modifying the tool's name to end with 'gcov'.
Differential Revision: http://reviews.llvm.org/D4445
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There is a fundamental difference between how the gold API and lib/LTO view
the LTO process.
The gold API talks about a particular symbol in a particular file. The lib/LTO
API talks about a symbol in the merged module.
The merged module is then defined in terms of the IR semantics. In particular,
a linkonce_odr GV is only copied if it is used, since it is valid to drop
unused linkonce_odr GVs.
In the testcase in pr19901 both properties collide. What happens is that gold
asks us to keep a particular linkonce_odr symbol, but the IR linker doesn't
copy it to the merged module and we never have a chance to ask lib/LTO to keep
it.
This patch fixes it by having a more direct implementation of the gold API. If
it asks us to keep a symbol, we change the linkage so it is not linkonce. If it
says we can drop a symbol, we do so. All of this before we even send the module
to lib/Linker.
Since now we don't have to produce LTO_SYMBOL_SCOPE_DEFAULT_CAN_BE_HIDDEN,
during symbol resolution we can use a temporary LLVMContext and do lazy
module loading. This allows us to keep the minimum possible amount of
allocated memory around. This should also allow as much parallelism as
we want, since there is no shared context.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216215 91177308-0d34-0410-b5e6-96231b3b80d8
Implement `uselistorder` and `uselistorder_bb` assembly directives,
which allow the use-list order to be recovered when round-tripping to
assembly.
This is the bulk of PR20515.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216025 91177308-0d34-0410-b5e6-96231b3b80d8
Owning the buffer is somewhat inflexible. Some Binaries have sub Binaries
(like Archive) and we had to create dummy buffers just to handle that. It is
also a bad fit for IRObjectFile where the Module wants to own the buffer too.
Keeping this ownership would make supporting IR inside native objects
particularly painful.
This patch focuses in lib/Object. If something elsewhere used to own an Binary,
now it also owns a MemoryBuffer.
This patch introduces a few new types.
* MemoryBufferRef. This is just a pair of StringRefs for the data and name.
This is to MemoryBuffer as StringRef is to std::string.
* OwningBinary. A combination of Binary and a MemoryBuffer. This is needed
for convenience functions that take a filename and return both the
buffer and the Binary using that buffer.
The C api now uses OwningBinary to avoid any change in semantics. I will start
a new thread to see if we want to change it and how.
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* Use StringRef instead of std::string&
* Return a std::unique_ptr<Module> instead of taking an optional module to write
to (was not really used).
* Use current comment style.
* Use current naming convention.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215989 91177308-0d34-0410-b5e6-96231b3b80d8
Call `verifyModule()` after parsing and after every transformation.
Also convert some `DEBUG(dbgs())` to `errs()` to increase visibility
into what's going on.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215951 91177308-0d34-0410-b5e6-96231b3b80d8
file with -macho, the Mach-O specific object file parser option.
After some discussion I chose to do this implementation contained in the logic
of llvm-objdump’s MachODump.cpp using a second disassembler for thumb when
needed and with updates mostly contained in the MachOObjectFile class.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215931 91177308-0d34-0410-b5e6-96231b3b80d8
Add header guards to files that were missing guards. Remove #endif comments
as they don't seem common in LLVM (we can easily add them back if we decide
they're useful)
Changes made by clang-tidy with minor tweaks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215558 91177308-0d34-0410-b5e6-96231b3b80d8
ARM bots (& others, I think, now that I look) were failing because we
were using incorrect printf-style format specifiers. They were wrong
on almost any platform, actually, just mostly harmlessly so.
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be deleted. This will be reapplied as soon as possible and before
the 3.6 branch date at any rate.
Approved by Jim Grosbach, Lang Hames, Rafael Espindola.
This reverts commits r215111, 215115, 215116, 215117, 215136.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215154 91177308-0d34-0410-b5e6-96231b3b80d8
I am sure we will be finding bits and pieces of dead code for years to
come, but this is a good start.
Thanks to Lang Hames for making MCJIT a good replacement!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215111 91177308-0d34-0410-b5e6-96231b3b80d8
Also make the disassembler created with the Mach-O parser (the -m option)
pick up the Target specific attributes specified with -mattr option.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215032 91177308-0d34-0410-b5e6-96231b3b80d8
mode.
This will cause -verify mode to report failure when RuntimeDyld encounters an
internal error (e.g. overflows in relocation computations). Previously we had
let these errors slip past unreported.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214925 91177308-0d34-0410-b5e6-96231b3b80d8
This is mostly a cleanup, but it changes a fairly old behavior.
Every "real" LTO user was already disabling the silly internalize pass
and creating the internalize pass itself. The difference with this
patch is for "opt -std-link-opts" and the C api.
Now to get a usable behavior out of opt one doesn't need the funny
looking command line:
opt -internalize -disable-internalize -internalize-public-api-list=foo,bar -std-link-opts
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214919 91177308-0d34-0410-b5e6-96231b3b80d8
Updated `verify-uselistorder` to more than double the number of use-list
orders it checks.
- Every time it verifies an order, it then reverses the order and
verifies again.
- It now verifies the initial order, before running any shuffles.
Changed the default to `-num-shuffles=1`, since this is already four
checks, and after r214584 shuffling is guaranteed to make a new order.
This is part of PR5680.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214596 91177308-0d34-0410-b5e6-96231b3b80d8
`shuffleUseLists()` is only used in `verify-uselistorder`, so move it
there to avoid bloating other executables. As a drive-by, update some
of the header docs.
This is part of PR5680.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214592 91177308-0d34-0410-b5e6-96231b3b80d8
Also fix the error handling. No testcaes, issue found by inspection.
Thanks to David Blaikie for the suggestion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214535 91177308-0d34-0410-b5e6-96231b3b80d8
Instead of moving out the data in a ErrorOr<std::unique_ptr<Foo>>, get
a reference to it.
Thanks to David Blaikie for the suggestion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214516 91177308-0d34-0410-b5e6-96231b3b80d8
"Create a default symver on Linux like ELF OSes."
Fails the build under Debian with ld.gold:
/usr/bin/ld.gold: --default-symver: unknown option
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214482 91177308-0d34-0410-b5e6-96231b3b80d8
Change the default for `-num-shuffles` to 5 and better document the
algorithm in the header docs of `verify-uselistorder`.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214419 91177308-0d34-0410-b5e6-96231b3b80d8
Turns out `parseBitcodeFile()` does *not* take ownership of the buffer.
This was already clear in the header docs, but I obviously didn't read
them (having noticed that it gets stored in a `unique_ptr<>`).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214313 91177308-0d34-0410-b5e6-96231b3b80d8
use in -verify mode.
This patch adds three hidden command line options to llvm-rtdyld:
-target-addr-start <start-addr> : Specify the start of the virtual address
space on the phony target.
-target-addr-end <end-addr> : Specify the end of the virtual address space
on the phony target.
-target-section-sep <sep> : Specify the separation (in bytes) between the
end of one section and the start of the next.
These options automatically default to sane values for the target platform. In
particular, they allow narrow (e.g. 32-bit, 16-bit) targets to be tested from
wider (e.g. 64-bit, 32-bit) hosts without overflowing pointers.
The section separation option defaults to zero, but can be set to a large number
(e.g. 1 << 32) to force large separations between sections in order to
stress-test large-code-model code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214255 91177308-0d34-0410-b5e6-96231b3b80d8
Predict and serialize use-list order in bitcode. This makes the option
`-preserve-bc-use-list-order` work *most* of the time, but this is still
experimental.
- Builds a full value-table up front in the writer, sets up a list of
use-list orders to write out, and discards the table. This is a
simpler first step than determining the order from the various
overlapping IDs of values on-the-fly.
- The shuffles stored in the use-list order list have an unnecessarily
large memory footprint.
- `blockaddress` expressions cause functions to be materialized
out-of-order. For now I've ignored this problem, so use-list orders
will be wrong for constants used by functions that have block
addresses taken. There are a couple of ways to fix this, but I
don't have a concrete plan yet.
- When materializing functions lazily, the use-lists for constants
will not be correct. This use case is out of scope: what should the
use-list order be, if it's incomplete?
This is part of PR5680.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214125 91177308-0d34-0410-b5e6-96231b3b80d8
The gcov compatible code is moved to its own file and
llvm-cov is updated to be a wrapper that always calls
the gcov main function.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214107 91177308-0d34-0410-b5e6-96231b3b80d8
Ugh. Turns out not even transformation passes link in how to read IR.
I sincerely believe the buildbots will finally agree with my system
after this though. (I don't really understand why all of this has been
working on my system, but not on all the buildbots.)
Create a new tool called llvm-uselistorder to use for verifying use-list
order. For now, just dump everything from the (now defunct)
-verify-use-list-order pass into the tool.
This might be a better way to test use-list order anyway.
Part of PR5680.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213957 91177308-0d34-0410-b5e6-96231b3b80d8
StringMap doesn't guarantee any particular iteration order,
this is suboptimal when comparing llvm-vtabledump's output for two
object files.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213921 91177308-0d34-0410-b5e6-96231b3b80d8
The -print-file-name option in llvm-nm is to precede each symbol
with the object file it came from. While code for the parsing of this
option and its aliases existed there was no code to implement it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213906 91177308-0d34-0410-b5e6-96231b3b80d8
This tool's job is to dump the vtables inside object files. It is
currently limited to MS ABI vf- and vb-tables but it will eventually
support Itanium-style v-tables as well.
Differential Revision: http://reviews.llvm.org/D4584
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213903 91177308-0d34-0410-b5e6-96231b3b80d8
This allows people to try clang inside MSBuild with the VS "14" CTP
releases.
Fixes PR20341.
Patch by Marcel Raad!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213819 91177308-0d34-0410-b5e6-96231b3b80d8
This patch introduces a 'stub_addr' builtin that can be used to find the address
of the stub for a given (<file>, <section>, <symbol>) tuple. This address can be
used both to verify the contents of stubs (by loading from the returned address)
and to verify references to stubs (by comparing against the returned address).
Example (1) - Verifying stub contents:
Load 8 bytes (assuming a 64-bit target) from the stub for 'x' in the __text
section of f.o, and compare that value against the addres of 'x'.
# rtdyld-check: *{8}(stub_addr(f.o, __text, x) = x
Example (2) - Verifying references to stubs:
Decode the immediate of the instruction at label 'l', and verify that it's
equal to the offset from the next instruction's PC to the stub for 'y' in the
__text section of f.o (i.e. it's the correct PC-rel difference).
# rtdyld-check: decode_operand(l, 4) = stub_addr(f.o, __text, y) - next_pc(l)
l:
movq y@GOTPCREL(%rip), %rax
Since stub inspection requires cooperation with RuntimeDyldImpl this patch
pimpl-ifies RuntimeDyldChecker. Its implementation is moved in to a new class,
RuntimeDyldCheckerImpl, that has access to the definition of RuntimeDyldImpl.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213698 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r213474 (and r213475), which causes a miscompile on
a stage2 LTO build. I'll reply on the list in a moment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213562 91177308-0d34-0410-b5e6-96231b3b80d8
createBinary documented that it destroyed the parameter in error cases,
though by observation it does not. By passing the unique_ptr by value
rather than lvalue reference, callers are now explicit about passing
ownership and the function implements the documented contract. Remove
the explicit documentation, since now the behavior cannot be anything
other than what was documented, so it's redundant.
Also drops a unique_ptr::release in llvm-nm that was always run on a
null unique_ptr anyway.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213557 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: This patch introduces two new iterator ranges and updates existing code to use it. No functional change intended.
Test Plan: All tests (make check-all) still pass.
Reviewers: dblaikie
Reviewed By: dblaikie
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D4481
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213474 91177308-0d34-0410-b5e6-96231b3b80d8
Until now, attempting to create an alias of a required option would
complain if the user supplied the alias, because the required option
didn't have a value. Similarly, if you said the alias was required,
then using the base option would complain that the alias wasn't
supplied. Lastly, if you put required on both, *neither* option would
work.
By changning alias to overload addOccurrence and setting cl::Required
on the original option, we can get this to behave in a more useful
way. I've also added a test and updated a user that was getting this
wrong.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212986 91177308-0d34-0410-b5e6-96231b3b80d8
The size of the uninitialized sections, like BSS, can exceed the size of
the object file.
Do not attempt to grab the contents of such sections.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212953 91177308-0d34-0410-b5e6-96231b3b80d8
the specified section. This is same functionality as darwin’s nm(1) "-s" flag.
There is one FIXME in the code and I’m all ears to anyone that can help me
with that. This option takes exactly two strings and should be allowed
anywhere on the command line. Such that "llvm-nm -s __TEXT __text foo.o"
would work. But that does not as the CommandLine Library does not have a
way to make this work as far as I can tell. For now the "-s __TEXT __text"
has to be last on the command line.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212842 91177308-0d34-0410-b5e6-96231b3b80d8
This will allow the "-s" flag to implemented in the future as it
is in darwin’s nm(1) to list symbols only in the specified section.
Given a LGTM by Shankar Easwaran who originally implemented
the support for lvm-nm’s -print-armap and archive map symbols.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212576 91177308-0d34-0410-b5e6-96231b3b80d8
Use 0 for the invalid buffer instead of -1/~0 and switch to unsigned
representation to enable more idiomatic usage.
Also introduce a trivial SourceMgr::getMainFileID() instead of hard-coding 0/1
to identify the main file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212398 91177308-0d34-0410-b5e6-96231b3b80d8
There were two issues here:
1. At the very least, scattered relocations cannot use the same code to
determine the corresponding symbol being referred to. For some reason we
pretend there is no symbol, even when one actually exists in the symtab, so to
match this behaviour getRelocationSymbol should simply return symbols_end for
scattered relocations.
2. Printing "-" when we can't get a symbol (including the scattered case, but
not exclusively), isn't that helpful. In both cases there *is* interesting
information in that field, so we should print it. As hex will do.
Small part of rdar://problem/17553104
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212332 91177308-0d34-0410-b5e6-96231b3b80d8
We want to encourage users of the C++ LTO API to reuse memory buffers instead
of repeatedly opening and reading the same file contents.
This reverts commit r212305 and implements a tidier scheme.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212308 91177308-0d34-0410-b5e6-96231b3b80d8
On at least my machine, ar does not register an all symbols read hook (which
previously triggered target initialization), but it does register a claim
files hook, which depends on the targets being initialized.
Differential Revision: http://reviews.llvm.org/D4372
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212303 91177308-0d34-0410-b5e6-96231b3b80d8
symbol’s name. On darwin the -j flag is used (often in combinations
with other flags) to produce a complete list of symbol names which
than can then be reorder and used with ld(1)’s -order_file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212294 91177308-0d34-0410-b5e6-96231b3b80d8
This should allow llvm-ar to be used instead of gnu ar + plugin in a LTO
build. I will add a release note about it once I finish a LTO bootstrap with it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212287 91177308-0d34-0410-b5e6-96231b3b80d8
Now that we have a lib/MC/MCAnalysis, the dependency was there just because
of two helper classes. Move the two over to MC.
This will allow IRObjectFile to parse inline assembly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212248 91177308-0d34-0410-b5e6-96231b3b80d8
The new library is 150KB on a Release+Asserts build, so it is quiet a bit of
code that regular users of MC don't need to link with now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212209 91177308-0d34-0410-b5e6-96231b3b80d8
to select the slice out of a Mach-O universal file. This also includes
support for -arch all, selecting the host architecture by default from
a universal file and checking if -arch is used with a standard Mach-O
it matches that architecture.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212108 91177308-0d34-0410-b5e6-96231b3b80d8
universal file. This also includes support for -arch all, selecting the host
architecture by default from a universal file and checking if -arch is used
with a standard Mach-O it matches that architecture.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212054 91177308-0d34-0410-b5e6-96231b3b80d8
Make llvm-cov compatible with gcov for cases where multiple files are
specified on the command line. That is, loop over each one and report
coverage, and report errors on stderr only rather than via return
code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211959 91177308-0d34-0410-b5e6-96231b3b80d8
This patch adds a "-verify" mode to the llvm-rtdyld utility. In verify mode,
llvm-rtdyld will test supplied expressions against the linked program images
that it creates in memory. This scheme can be used to verify the correctness
of the relocation logic applied by RuntimeDyld.
The expressions to test will be read out of files passed via the -check option
(there may be more than one of these). Expressions to check are extracted from
lines of the form:
# rtdyld-check: <expression>
This system is designed to fit the llvm-lit regression test workflow. It is
format and target agnostic, and supports verification of images linked for
remote targets. The expression language is defined in
llvm/include/llvm/RuntimeDyldChecker.h . Examples can be found in
test/ExecutionEngine/RuntimeDyld.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211956 91177308-0d34-0410-b5e6-96231b3b80d8
Add the new AppContainer characteristic which is import for Windows Store
(Metro) compatible applications. Add the new Control Flow Guard flag to bring
the enumeration up to date with the current values as of Windows 8.1.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211855 91177308-0d34-0410-b5e6-96231b3b80d8
Any uses of tools/lto as a static lib should probably move to lib/LTO.
This was also never implemented in the configure build, so this reduces
the differences among the two.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211852 91177308-0d34-0410-b5e6-96231b3b80d8
This fixes a regression that made clang -flto -Wl,--plugin-opt=-mattr=+aes not
pass the "+aes" option to the LTOCodeGenerator attributes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211804 91177308-0d34-0410-b5e6-96231b3b80d8
string_ostream is a safe and efficient string builder that combines opaque
stack storage with a built-in ostream interface.
small_string_ostream<bytes> additionally permits an explicit stack storage size
other than the default 128 bytes to be provided. Beyond that, storage is
transferred to the heap.
This convenient class can be used in most places an
std::string+raw_string_ostream pair or SmallString<>+raw_svector_ostream pair
would previously have been used, in order to guarantee consistent access
without byte truncation.
The patch also converts much of LLVM to use the new facility. These changes
include several probable bug fixes for truncated output, a programming error
that's no longer possible with the new interface.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211749 91177308-0d34-0410-b5e6-96231b3b80d8
