This classof() is effectively saying that a MachineCodeEmitter "is-a"
JITEmitter, but JITEmitter is in fact a descendant of
MachineCodeEmitter, so this is not semantically correct. Consequently,
none of the assertions that rely on these classof() actualy check
anything.
Remove the RTTI (which didn't actually check anything) and use
static_cast<> instead.
Post-Mortem Bug Analysis
========================
Cause of the bug
----------------
r55022 appears to be the source of the classof() and assertions removed
by this commit. It aimed at removing some dynamic_cast<> that were
solely in the assertions. A typical diff hunk from that commit looked
like:
- assert(dynamic_cast<JITEmitter*>(MCE) && "Unexpected MCE?");
- JITEmitter *JE = static_cast<JITEmitter*>(getCodeEmitter());
+ assert(isa<JITEmitter>(MCE) && "Unexpected MCE?");
+ JITEmitter *JE = cast<JITEmitter>(getCodeEmitter());
Hence, the source of the bug then seems to be an attempt to replace
dynamic_cast<> with LLVM-style RTTI without properly setting up the
class hierarchy for LLVM-style RTTI. The bug therefore appears to be
simply a "thinko".
What initially indicated the presence of the bug
------------------------------------------------
After implementing automatic upcasting for isa<>, classof() functions of
the form
static bool classof(const Foo *) { return true; }
were removed, since they only serve the purpose of optimizing
statically-OK upcasts. A subsequent recompilation triggered a build
failure on the isa<> tests within the removed asserts, since the
automatic upcasting (correctly) failed to substitute this classof().
Key to pinning down the root cause of the bug
---------------------------------------------
After being alerted to the presence of the bug, some thought about the
semantics which were being asserted by the buggy classof() revealed that
it was incorrect.
How the bug could have been prevented
-------------------------------------
This bug could have been prevented by better documentation for how to
set up LLVM-style RTTI. This should be solved by the recently added
documentation HowToSetUpLLVMStyleRTTI. However, this bug suggests that
the documentation should clearly explain the contract that classof()
must fulfill. The HowToSetUpLLVMStyleRTTI already explains this
contract, but it is a little tucked away. A future patch will expand
that explanation and make it more prominent.
There does not appear to be a simple way to have the compiler prevent
this bug, since fundamentally it boiled down to a spurious classof()
where the programmer made an erroneous statement about the conversion.
This suggests that perhaps the interface to LLVM-style RTTI of classof()
is not the best. There is already some evidence for this, since in a
number of places Clang has classof() forward to classofKind(Kind K)
which evaluates the cast in terms of just the Kind. This could probably
be generalized to simply a `static const Kind MyKind;` field in leaf
classes and `static const Kind firstMyKind, lastMyKind;` for non-leaf
classes, and have the rest of the work be done inside Casting.h,
assuming that the Kind enum is laid out in a preorder traversal of the
inheritance tree.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165764 91177308-0d34-0410-b5e6-96231b3b80d8
allocations of executable memory would not be padded
to account for the size of the allocation header.
This resulted in undersized allocations, meaning that
when the allocation was written to later the next
allocation's header would be corrupted.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161984 91177308-0d34-0410-b5e6-96231b3b80d8
include/llvm/Analysis/DebugInfo.h to include/llvm/DebugInfo.h.
The reasoning is because the DebugInfo module is simply an interface to the
debug info MDNodes and has nothing to do with analysis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159312 91177308-0d34-0410-b5e6-96231b3b80d8
(and hopefully on Windows). The bots have been down most of the day
because of this, and it's not clear to me what all will be required to
fix it.
The commits started with r153205, then r153207, r153208, and r153221.
The first commit seems to be the real culprit, but I couldn't revert
a smaller number of patches.
When resubmitting, r153207 and r153208 should be folded into r153205,
they were simple build fixes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153241 91177308-0d34-0410-b5e6-96231b3b80d8
1. Declare a virtual function getPointerToNamedFunction() in JITMemoryManager
2. Move the implementation of getPointerToNamedFunction() form JIT/MCJIT to DefaultJITMemoryManager.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153205 91177308-0d34-0410-b5e6-96231b3b80d8
Also refactor the existing OProfile profiling code to reuse the same interfaces with the VTune profiling code.
In addition, unit tests for the profiling interfaces were added.
This patch was prepared by Andrew Kaylor and Daniel Malea, and reviewed in the llvm-commits list by Jim Grosbach
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152620 91177308-0d34-0410-b5e6-96231b3b80d8
needed to emit a 64-bit gp-relative relocation entry. Make changes necessary
for emitting jump tables which have entries with directive .gpdword. This patch
does not implement the parts needed for direct object emission or JIT.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149668 91177308-0d34-0410-b5e6-96231b3b80d8
Move to a by-section allocation and relocation scheme. This allows
better support for sections which do not contain externally visible
symbols.
Flesh out the relocation address vs. local storage address separation a
bit more as well. Remote process JITs use this to tell the relocation
resolution code where the code will live when it executes.
The startFunctionBody/endFunctionBody interfaces to the JIT and the
memory manager are deprecated. They'll stick around for as long as the
old JIT does, but the MCJIT doesn't use them anymore.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148258 91177308-0d34-0410-b5e6-96231b3b80d8
The OptLevel is now redundant with the TargetMachine*.
And selectTarget() isn't really JIT-specific and could probably
get refactored into one of the lower level libraries.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146355 91177308-0d34-0410-b5e6-96231b3b80d8
generator to it. For non-bundle instructions, these behave exactly the same
as the MC layer API.
For properties like mayLoad / mayStore, look into the bundle and if any of the
bundled instructions has the property it would return true.
For properties like isPredicable, only return true if *all* of the bundled
instructions have the property.
For properties like canFoldAsLoad, isCompare, conservatively return false for
bundles.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146026 91177308-0d34-0410-b5e6-96231b3b80d8
change, now you need a TargetOptions object to create a TargetMachine. Clang
patch to follow.
One small functionality change in PTX. PTX had commented out the machine
verifier parts in their copy of printAndVerify. That now calls the version in
LLVMTargetMachine. Users of PTX who need verification disabled should rely on
not passing the command-line flag to enable it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145714 91177308-0d34-0410-b5e6-96231b3b80d8
It was getting ignored after r144788.
Also fix an accidental implicit cast from the OptLevel enum
to an optional bool argument. MSVC warned on this, but gcc
didn't.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145633 91177308-0d34-0410-b5e6-96231b3b80d8
specified in the same file that the library itself is created. This is
more idiomatic for CMake builds, and also allows us to correctly specify
dependencies that are missed due to bugs in the GenLibDeps perl script,
or change from compiler to compiler. On Linux, this returns CMake to
a place where it can relably rebuild several targets of LLVM.
I have tried not to change the dependencies from the ones in the current
auto-generated file. The only places I've really diverged are in places
where I was seeing link failures, and added a dependency. The goal of
this patch is not to start changing the dependencies, merely to move
them into the correct location, and an explicit form that we can control
and change when necessary.
This also removes a serialization point in the build because we don't
have to scan all the libraries before we begin building various tools.
We no longer have a step of the build that regenerates a file inside the
source tree. A few other associated cleanups fall out of this.
This isn't really finished yet though. After talking to dgregor he urged
switching to a single CMake macro to construct libraries with both
sources and dependencies in the arguments. Migrating from the two macros
to that style will be a follow-up patch.
Also, llvm-config is still generated with GenLibDeps.pl, which means it
still has slightly buggy dependencies. The internal CMake
'llvm-config-like' macro uses the correct explicitly specified
dependencies however. A future patch will switch llvm-config generation
(when using CMake) to be based on these deps as well.
This may well break Windows. I'm getting a machine set up now to dig
into any failures there. If anyone can chime in with problems they see
or ideas of how to solve them for Windows, much appreciated.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136433 91177308-0d34-0410-b5e6-96231b3b80d8
- Introduce JITDefault code model. This tells targets to set different default
code model for JIT. This eliminates the ugly hack in TargetMachine where
code model is changed after construction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135580 91177308-0d34-0410-b5e6-96231b3b80d8
(including compilation, assembly). Move relocation model Reloc::Model from
TargetMachine to MCCodeGenInfo so it's accessible even without TargetMachine.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135468 91177308-0d34-0410-b5e6-96231b3b80d8
As an ExecutionEngine class function, its definition
really belongs in ExecutionEngine.cpp, not JIT.cpp.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131320 91177308-0d34-0410-b5e6-96231b3b80d8
In particular, into EngineBuilder. This should only impact
the private API between the EE and EB classes, not external
clients, since JITCtor and MCJITCtor are both protected members.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131317 91177308-0d34-0410-b5e6-96231b3b80d8
This prepares for making JITCtor/MCJITCtor take a
TargetMachine* directly from clients like EngineBuilder.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131316 91177308-0d34-0410-b5e6-96231b3b80d8
As an ExecutionEngine class function, its definition
really belongs in ExecutionEngine.cpp, not JIT.cpp.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131027 91177308-0d34-0410-b5e6-96231b3b80d8
In particular, into EngineBuilder. This should only impact
the private API between the EE and EB classes, not external
clients, since JITCtor and MCJITCtor are both protected members.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131026 91177308-0d34-0410-b5e6-96231b3b80d8
This prepares for making JITCtor/MCJITCtor take a
TargetMachine* directly from clients like EngineBuilder.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131025 91177308-0d34-0410-b5e6-96231b3b80d8
