This commit switches the underlying JIT for the Kaleidoscope tutorials from
MCJIT to a custom ORC-based JIT, KaleidoscopeJIT. This fixes a lot of the bugs
in Kaleidoscope that were introduced when we deleted the legacy JIT. The
documentation for Chapter 4, which introduces the JIT APIs, is updated to
reflect the change.
Also included are a number of C++11 modernizations and general cleanup. Where
appropriate, the docs have been updated to reflect these changes too.
llvm-svn: 246002
This is the first mechanical step in preparation for making this and all
the other alias analysis passes available to the new pass manager. I'm
factoring out all the totally boring changes I can so I'm moving code
around here with no other changes. I've even minimized the formatting
churn.
I'll reformat and freshen comments on the interface now that its located
in the right place so that the substantive changes don't triger this.
llvm-svn: 244197
Replace the general `createLocalVariable()` with two more specific
functions: `createParameterVariable()` and `createAutoVariable()`, and
rewrite the documentation.
Besides cleaning up the API, this avoids exposing the fake DWARF tags
`DW_TAG_arg_variable` and `DW_TAG_auto_variable` to frontends, and is
preparation for removing them completely.
llvm-svn: 243764
Add a verifier check that `DILocalVariable`s of tag
`DW_TAG_arg_variable` always have a non-zero 'arg:' field, and those of
tag `DW_TAG_auto_variable` always have a zero 'arg:' field. These are
the only configurations that are properly understood by the backend.
(Also, fix the bad examples in LangRef and test/Assembler, and fix the
bug in Kaleidoscope Ch8.)
A large number of testcases seem to have bitrotted their way forward
from some ancient version of the debug info hierarchy that didn't have
`arg:` parameters. If you have out-of-tree testcases that start failing
in the verifier and you don't care enough to get the `arg:` right, you
may have some luck just calling:
sed -e 's/, arg: 0/, arg: 1/'
or some such, but I hand-updated the ones in tree.
llvm-svn: 243183
Summary:
Replace getDataLayout() with a createDataLayout() method to make
explicit that it is intended to create a DataLayout only and not
accessing it for other purpose.
This change is the last of a series of commits dedicated to have a
single DataLayout during compilation by using always the one owned
by the module.
Reviewers: echristo
Subscribers: jholewinski, llvm-commits, rafael, yaron.keren
Differential Revision: http://reviews.llvm.org/D11103
(cherry picked from commit 5609fc56bca971e5a7efeaa6ca4676638eaec5ea)
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 243114
This reverts commit 0f720d984f419c747709462f7476dff962c0bc41.
It breaks clang too badly, I need to prepare a proper patch for clang
first.
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 243089
Summary:
Replace getDataLayout() with a createDataLayout() method to make
explicit that it is intended to create a DataLayout only and not
accessing it for other purpose.
This change is the last of a series of commits dedicated to have a
single DataLayout during compilation by using always the one owned
by the module.
Reviewers: echristo
Subscribers: jholewinski, llvm-commits, rafael, yaron.keren
Differential Revision: http://reviews.llvm.org/D11103
(cherry picked from commit 5609fc56bca971e5a7efeaa6ca4676638eaec5ea)
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 243083
and avoid cloning unused decls into every partition.
Module partitioning showed up as a source of significant overhead when I
profiled some trivial test cases. Avoiding the overhead of partitionging
for uncalled functions helps to mitigate this.
This change also means that it is no longer necessary to have a
LazyEmittingLayer underneath the CompileOnDemand layer, since the
CompileOnDemandLayer will not extract or emit function bodies until they are
called.
llvm-svn: 236465
Finish off PR23080 by renaming the debug info IR constructs from `MD*`
to `DI*`. The last of the `DIDescriptor` classes were deleted in
r235356, and the last of the related typedefs removed in r235413, so
this has all baked for about a week.
Note: If you have out-of-tree code (like a frontend), I recommend that
you get everything compiling and tests passing with the *previous*
commit before updating to this one. It'll be easier to keep track of
what code is using the `DIDescriptor` hierarchy and what you've already
updated, and I think you're extremely unlikely to insert bugs. YMMV of
course.
Back to *this* commit: I did this using the rename-md-di-nodes.sh
upgrade script I've attached to PR23080 (both code and testcases) and
filtered through clang-format-diff.py. I edited the tests for
test/Assembler/invalid-generic-debug-node-*.ll by hand since the columns
were off-by-three. It should work on your out-of-tree testcases (and
code, if you've followed the advice in the previous paragraph).
Some of the tests are in badly named files now (e.g.,
test/Assembler/invalid-mdcompositetype-missing-tag.ll should be
'dicompositetype'); I'll come back and move the files in a follow-up
commit.
llvm-svn: 236120
Replace uses of `DIScope` with `MDScope*`. There was one spot where
I've left an `MDScope*` uninitialized (where `DIScope` would have been
default-initialized to `nullptr`) -- this is intentional, since the
if/else that follows should unconditional assign it to a value.
llvm-svn: 235327
As a step toward killing `DIDescriptor` and its subclasses, remove it
from the `DIBuilder` API. Replace the subclasses with appropriate
pointers from the new debug info hierarchy. There are a couple of
possible surprises in type choices for out-of-tree frontends:
- Subroutine types: `MDSubroutineType`, not `MDCompositeTypeBase`.
- Composite types: `MDCompositeType`, not `MDCompositeTypeBase`.
- Scopes: `MDScope`, not `MDNode`.
- Generic debug info nodes: `DebugNode`, not `MDNode`.
This is part of PR23080.
llvm-svn: 235111
PR23080 is almost finished. With this commit, there's no consequential
API in `DIDescriptor` and its subclasses. What's left?
- Default-constructed to `nullptr`.
- Handy `const_cast<>` (constructed from `const`, but accessors are
non-`const`).
I think the safe way to catch those is to delete the classes and fix
compile errors. That'll be my next step, after I delete the `DITypeRef`
(etc.) wrapper around `MDTypeRef`.
llvm-svn: 235069
Remove the accessors of `DIDerivedType` that downcast to
`MDDerivedType`, shifting the `cast<MDDerivedType>` into the callers.
Also remove `DIType::isValid()`, which is really just a check against
`nullptr` at this point.
llvm-svn: 235059
As a follow-up to r234850, add an implicit conversion from
`DISubprogram` to `DIScope` to support Kaleidoscope Ch. 8. This also
reverts that band-aid from r234890.
(/me learns *again* to build Kaleidoscope before commit...)
llvm-svn: 234904
The patch is generated using clang-tidy misc-use-override check.
This command was used:
tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py \
-checks='-*,misc-use-override' -header-filter='llvm|clang' \
-j=32 -fix -format
http://reviews.llvm.org/D8925
llvm-svn: 234679
examples/ExceptionDemo/CMakeFiles/ExceptionDemo.dir/ExceptionDemo.cpp.o:(.data.rel.ro._ZTIN4llvm18MCJITMemoryManagerE[_ZTIN4llvm18MCJITMemoryManagerE]+0x10): undefined reference to `typeinfo for llvm::RuntimeDyld::MemoryManager'
llvm-svn: 233647
MCJIT.
This patch decouples the two responsibilities of the RTDyldMemoryManager class,
memory management and symbol resolution, into two new classes:
RuntimeDyld::MemoryManager and RuntimeDyld::SymbolResolver.
The symbol resolution interface is modified slightly, from:
uint64_t getSymbolAddress(const std::string &Name);
to:
RuntimeDyld::SymbolInfo findSymbol(const std::string &Name);
The latter passes symbol flags along with symbol addresses, allowing RuntimeDyld
and others to reason about non-strong/non-exported symbols.
The memory management interface removes the following method:
void notifyObjectLoaded(ExecutionEngine *EE,
const object::ObjectFile &) {}
as it is not related to memory management. (Note: Backwards compatibility *is*
maintained for this method in MCJIT and OrcMCJITReplacement, see below).
The RTDyldMemoryManager class remains in-tree for backwards compatibility.
It inherits directly from RuntimeDyld::SymbolResolver, and indirectly from
RuntimeDyld::MemoryManager via the new MCJITMemoryManager class, which
just subclasses RuntimeDyld::MemoryManager and reintroduces the
notifyObjectLoaded method for backwards compatibility).
The EngineBuilder class retains the existing method:
EngineBuilder&
setMCJITMemoryManager(std::unique_ptr<RTDyldMemoryManager> mcjmm);
and includes two new methods:
EngineBuilder&
setMemoryManager(std::unique_ptr<MCJITMemoryManager> MM);
EngineBuilder&
setSymbolResolver(std::unique_ptr<RuntimeDyld::SymbolResolver> SR);
Clients should use EITHER:
A single call to setMCJITMemoryManager with an RTDyldMemoryManager.
OR (exclusive)
One call each to each of setMemoryManager and setSymbolResolver.
This patch should be fully compatible with existing uses of RTDyldMemoryManager.
If it is not it should be considered a bug, and the patch either fixed or
reverted.
If clients find the new API to be an improvement the goal will be to deprecate
and eventually remove the RTDyldMemoryManager class in favor of the new classes.
llvm-svn: 233509
The MSVC linker won't produce a .lib file for an executable that doesn't
export anything, and LLVM doesn't maintain dllexport annotations or .def
files listing all C++ symbols. It also doesn't support exporting all
symbols, like binutils ld.
CMake 3.2 changed the Ninja generator to list both the .exe and .lib
files as outputs of executable build targets. Ninja would always re-link
executables with ENABLE_EXPORTS because the .lib output file was not
present, and therefore the target was out of date.
llvm-svn: 232662
Summary:
DataLayout keeps the string used for its creation.
As a side effect it is no longer needed in the Module.
This is "almost" NFC, the string is no longer
canonicalized, you can't rely on two "equals" DataLayout
having the same string returned by getStringRepresentation().
Get rid of DataLayoutPass: the DataLayout is in the Module
The DataLayout is "per-module", let's enforce this by not
duplicating it more than necessary.
One more step toward non-optionality of the DataLayout in the
module.
Make DataLayout Non-Optional in the Module
Module->getDataLayout() will never returns nullptr anymore.
Reviewers: echristo
Subscribers: resistor, llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D7992
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 231270
The version of the tutorial uses the new compile callbacks API to inject stubs
that trigger IRGen & Codegen of their respective function bodies when they are
first called.
llvm-svn: 229466
llvm/PassManager.h wrapper header and its using declarations. These now
directly use the legacy namespace.
I had updated the #include lines in my large commit but forgot that the
examples weren't being built and didn't update the code to use the
correct namespace. Sorry for the noise here.
llvm-svn: 229095
LLVM's include tree and the use of using declarations to hide the
'legacy' namespace for the old pass manager.
This undoes the primary modules-hostile change I made to keep
out-of-tree targets building. I sent an email inquiring about whether
this would be reasonable to do at this phase and people seemed fine with
it, so making it a reality. This should allow us to start bootstrapping
with modules to a certain extent along with making it easier to mix and
match headers in general.
The updates to any code for users of LLVM are very mechanical. Switch
from including "llvm/PassManager.h" to "llvm/IR/LegacyPassManager.h".
Qualify the types which now produce compile errors with "legacy::". The
most common ones are "PassManager", "PassManagerBase", and
"FunctionPassManager".
llvm-svn: 229094
This patch refactors a key piece of the Orc APIs: It removes the
*::getSymbolAddress and *::lookupSymbolAddressIn methods, which returned target
addresses (uint64_ts), and replaces them with *::findSymbol and *::findSymbolIn
respectively, which return instances of the new JITSymbol type. Unlike the old
methods, calling findSymbol or findSymbolIn does not cause the symbol to be
immediately materialized when found. Instead, the symbol will be materialized
if/when the getAddress method is called on the returned JITSymbol. This allows
us to query for the existence of symbols without actually materializing them. In
the future I expect more information to be attached to the JITSymbol class, for
example whether the returned symbol is a weak or strong definition. This will
allow us to properly handle weak symbols and multiple definitions.
llvm-svn: 228557
This tutorial builds on the lazy_codegen kaleidoscope/orc tutorial by making
a small set of changes (~75 lines diff) to defer ir-generation for function
definitions until functions are actually referenced.
llvm-svn: 228466
This tutorial builds on the initial kaleidoscope/orc tutorial by adding a
LazyEmittingLayer to the custom stack. This extra layer defers compilation
of modules in the JIT until they are statically referenced.
llvm-svn: 228459
This tutorial demonstrates a very basic custom Orc JIT stack that performs eager
compilation: All modules are CodeGen'd immediately upon being added to the JIT.
llvm-svn: 228456
a description of how to add debug information using DWARF and
DIBuilder to the language.
Thanks to David Blaikie for his assistance with this tutorial.
llvm-svn: 223671
With this a DataLayoutPass can be reused for multiple modules.
Once we have doInitialization/doFinalization, it doesn't seem necessary to pass
a Module to the constructor.
Overall this change seems in line with the idea of making DataLayout a required
part of Module. With it the only way of having a DataLayout used is to add it
to the Module.
llvm-svn: 217548
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.
llvm-svn: 216393
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.
llvm-svn: 215154
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!
llvm-svn: 215111
to globally be controlled. Individual targets (e.g. ExceptionDemo) can
still override this by using LLVM_REQUIRE_RTTI and LLVM_REQUIRE_EH if
they need to be compiled with RTTI or exception handling respectively.
llvm-svn: 213663
This compiles with no changes to clang/lld/lldb with MSVC and includes
overloads to various functions which are used by those projects and llvm
which have OwningPtr's as parameters. This should allow out of tree
projects some time to move. There are also no changes to libs/Target,
which should help out of tree targets have time to move, if necessary.
llvm-svn: 203083
Eventually DataLayoutPass should go away, but for now that is the only easy
way to get a DataLayout in some APIs. This patch only changes the ones that
have easy access to a Module.
One interesting issue with sometimes using DataLayoutPass and sometimes
fetching it from the Module is that we have to make sure they are equivalent.
We can get most of the way there by always constructing the pass with a Module.
In fact, the pass could be changed to point to an external DataLayout instead
of owning one to make this stricter.
Unfortunately, the C api passes a DataLayout, so it has to be up to the caller
to make sure the pass and the module are in sync.
llvm-svn: 202204
After this I will set the default back to F_None. The advantage is that
before this patch forgetting to set F_Binary would corrupt a file on windows.
Forgetting to set F_Text produces one that cannot be read in notepad, which
is a better failure mode :-)
llvm-svn: 202052
r201608 made llvm corretly handle private globals with MachO. r201622 fixed
a bug in it and r201624 and r201625 were changes for using private linkage,
assuming that llvm would do the right thing.
They all got reverted because r201608 introduced a crash in LTO. This patch
includes a fix for that. The issue was that TargetLoweringObjectFile now has
to be initialized before we can mangle names of private globals. This is
trivially true during the normal codegen pipeline (the asm printer does it),
but LTO has to do it manually.
llvm-svn: 201700
This patch places class definitions in implementation files into anonymous
namespaces to prevent weak vtables. This eliminates the need of providing an
out-of-line definition to pin the vtable explicitly to the file.
llvm-svn: 195092
This patch removes most of the trivial cases of weak vtables by pinning them to
a single object file. The memory leaks in this version have been fixed. Thanks
Alexey for pointing them out.
Differential Revision: http://llvm-reviews.chandlerc.com/D2068
Reviewed by Andy
llvm-svn: 195064
This change is incorrect. If you delete virtual destructor of both a base class
and a subclass, then the following code:
Base *foo = new Child();
delete foo;
will not cause the destructor for members of Child class. As a result, I observe
plently of memory leaks. Notable examples I investigated are:
ObjectBuffer and ObjectBufferStream, AttributeImpl and StringSAttributeImpl.
llvm-svn: 194997
This patch removes most of the trivial cases of weak vtables by pinning them to
a single object file.
Differential Revision: http://llvm-reviews.chandlerc.com/D2068
Reviewed by Andy
llvm-svn: 194865
The old jit always uses DW_EH_PE_absptr, but MCJIT can use other encodings.
This is in preparation for adding EH support to MCJIT, but not directly
related, so I am committing it first.
llvm-svn: 180883
This was always part of the VMCore library out of necessity -- it deals
entirely in the IR. The .cpp file in fact was already part of the VMCore
library. This is just a mechanical move.
I've tried to go through and re-apply the coding standard's preferred
header sort, but at 40-ish files, I may have gotten some wrong. Please
let me know if so.
I'll be committing the corresponding updates to Clang and Polly, and
Duncan has DragonEgg.
Thanks to Bill and Eric for giving the green light for this bit of cleanup.
llvm-svn: 159421
llvm-ld is no longer useful and causes confusion and so it is being removed.
* Does not work very well on Windows because it must call a gcc like driver to
assemble and link.
* Has lots of hard coded paths which are wrong on many systems.
* Does not understand most of ld's options.
* Can be partially replaced by llvm-link | opt | {llc | as, llc -filetype=obj} |
ld, or fully replaced by Clang.
I know of no production use of llvm-ld, and hacking use should be
replaced by Clang's driver.
llvm-svn: 155147
Also conducted some reformatting. As the LLVM coding standard doc does not
seem to touch on how to align function arguments, and format code longer than
80 cols in general, the confusion persists. There is the golden rule, but as
this code has gone through several styles to deal with this, the golden rule
seems to be ignored. The latest reformatting effort tries to match the other
source files as much as possible.
Tested on OS X 10.7.1 with, and without the OLD_EXC_SYSTEM defined. Have NOT
tested on LINUX.
llvm-svn: 140379
was compiled and tested on OS X 10.7.1. It was not tested on LINUX. In
addition the defined OLD_EXC_SYSTEM was not tested with this version.
llvm-svn: 140303
infrastructure. As this makes the demo no longer a demo, and especially not a
demo on how to use the llvm exception mechanism, this hack will shortly be
changed to use the new 3.0 exception infrastructure. However for the time being
this demo is an example on how to use the AutoUpgrade
UpgradeExceptionHandling(...) function on < 3.0 exception handling code.
llvm-svn: 140301
1,$s/llvm::Type::getInt\(..\)Ty(builder.getContext())/builder.getInt\1Ty()/g
1,$s/builder.getInt\(..*\)Ty()->getPointerTo()/builder.getInt\1PtrTy()/g
vi sub commands (second one was not a reversion but requested by
Tobias Grosser.
Mod was tested, but other examples have failed to build as they are currently
being thrashed with the const qualifier removal change.
llvm-svn: 134985
type system. However most of these modifications were due to IRBuilder
(IRBuilderBase), not having been modified to NOT return such const qualified
free types. If IRBuilder does not change, as can also be seen in its
instruction creation methods, to use const free types, it may be useful to have
ExceptionDemo drop IRBuilder usage. Modifying builder.getInt32Ty() to
llvm::Type::getInt32Ty(builder.getContext()) is pretty ugly.
llvm-svn: 134901
x86 and x86_64 on UNIX systems. Only OS X 10.6.2 (x86_64) and 32bit CentOS 5.2
with gcc 4.1.2 were tested. ARM UNIX build triggered failure motivating this
modification, as it seems that the ARM ABI does not support _Unwind_GetIP(...),
_Unwind_SetGR(...), and _Unwind_SetIP(...). From doing a quick browse of:
http://infocenter.arm.com/help/topic/com.arm.doc.ihi0038a/IHI0038A_ehabi.pdf,
it seems as if all other exception related apis are supported. Looks like
the port can be done to ARM. Thanks to Xerxes Rånby <xerxes@zafena.se> for
pointing out this error.
llvm-svn: 96949
work anyway (Interpreter::getPointerToFunction doesn't return a
callable pointer), and improve the error message when an
ExecutionEngine can't be created.
llvm-svn: 95896
Both zero cost example domain specific, and C++ foreign exception handling are
shown. The example's documentation fully explains how to run the example.
Notes:
1) The code uses an extremely simple type info model.
2) Only a single landing pad is used per unwind edge
(one call to llvm.eh.selector)
3) llvm.eh.selector support for filter arguments is not given.
4) llvm.eh.typeid.for is not used.
5) Forced unwind behavior is not supported.
6) Very little if any error handling is given.
7) __attribute__((__aligned__)) is used.
8) The code uses parts from the llvm compiler-rt project and
the llvm Kaleidoscope example.
9) The code has not been ported or tested on WINDOWS.
10) The code was not tested with a cmake build.
11) The code was tested for a debug build on 32bit X86 CentOS LINUX,
and both a debug and release build on OS X 10.6.2 (64bit).
llvm-svn: 95723
Modules and ModuleProviders. Because the "ModuleProvider" simply materializes
GlobalValues now, and doesn't provide modules, it's renamed to
"GVMaterializer". Code that used to need a ModuleProvider to materialize
Functions can now materialize the Functions directly. Functions no longer use a
magic linkage to record that they're materializable; they simply ask the
GVMaterializer.
Because the C ABI must never change, we can't remove LLVMModuleProviderRef or
the functions that refer to it. Instead, because Module now exposes the same
functionality ModuleProvider used to, we store a Module* in any
LLVMModuleProviderRef and translate in the wrapper methods. The bindings to
other languages still use the ModuleProvider concept. It would probably be
worth some time to update them to follow the C++ more closely, but I don't
intend to do it.
Fixes http://llvm.org/PR5737 and http://llvm.org/PR5735.
llvm-svn: 94686
Here is the original commit message:
This commit updates malloc optimizations to operate on malloc calls that have constant int size arguments.
Update CreateMalloc so that its callers specify the size to allocate:
MallocInst-autoupgrade users use non-TargetData-computed allocation sizes.
Optimization uses use TargetData to compute the allocation size.
Now that malloc calls can have constant sizes, update isArrayMallocHelper() to use TargetData to determine the size of the malloced type and the size of malloced arrays.
Extend getMallocType() to support malloc calls that have non-bitcast uses.
Update OptimizeGlobalAddressOfMalloc() to optimize malloc calls that have non-bitcast uses. The bitcast use of a malloc call has to be treated specially here because the uses of the bitcast need to be replaced and the bitcast needs to be erased (just like the malloc call) for OptimizeGlobalAddressOfMalloc() to work correctly.
Update PerformHeapAllocSRoA() to optimize malloc calls that have non-bitcast uses. The bitcast use of the malloc is not handled specially here because ReplaceUsesOfMallocWithGlobal replaces through the bitcast use.
Update OptimizeOnceStoredGlobal() to not care about the malloc calls' bitcast use.
Update all globalopt malloc tests to not rely on autoupgraded-MallocInsts, but instead use explicit malloc calls with correct allocation sizes.
llvm-svn: 86311
MallocInst-autoupgrade users use non-TargetData-computed allocation sizes.
Optimization uses use TargetData to compute the allocation size.
Now that malloc calls can have constant sizes, update isArrayMallocHelper() to use TargetData to determine the size of the malloced type and the size of malloced arrays.
Extend getMallocType() to support malloc calls that have non-bitcast uses.
Update OptimizeGlobalAddressOfMalloc() to optimize malloc calls that have non-bitcast uses. The bitcast use of a malloc call has to be treated specially here because the uses of the bitcast need to be replaced and the bitcast needs to be erased (just like the malloc call) for OptimizeGlobalAddressOfMalloc() to work correctly.
Update PerformHeapAllocSRoA() to optimize malloc calls that have non-bitcast uses. The bitcast use of the malloc is not handled specially here because ReplaceUsesOfMallocWithGlobal replaces through the bitcast use.
Update OptimizeOnceStoredGlobal() to not care about the malloc calls' bitcast use.
Update all globalopt malloc tests to not rely on autoupgraded-MallocInsts, but instead use explicit malloc calls with correct allocation sizes.
llvm-svn: 86077
Update testcases that rely on malloc insts being present.
Also prematurely remove MallocInst handling from IndMemRemoval and RaiseAllocations to help pass tests in this incremental step.
llvm-svn: 84292
This is conventional command-line tool behavior. -f now just means
"enable binary output on terminals".
Add a -f option to llvm-extract and llvm-link, for consistency.
Remove F_Force from raw_fd_ostream and enable overwriting and
truncating by default. Introduce an F_Excl flag to permit users to
enable a failure when the file already exists. This flag is
currently unused.
Update Makefiles and documentation accordingly.
llvm-svn: 79990
This involves temporarily hard wiring some parts to use the global context. This isn't ideal, but it's
the only way I could figure out to make this process vaguely incremental.
llvm-svn: 75445