constants in commented-out part of LLVMAttribute enum. Add tests that verify
that the safestack attribute is only allowed as a function attribute.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239772 91177308-0d34-0410-b5e6-96231b3b80d8
This patch adds the safe stack instrumentation pass to LLVM, which separates
the program stack into a safe stack, which stores return addresses, register
spills, and local variables that are statically verified to be accessed
in a safe way, and the unsafe stack, which stores everything else. Such
separation makes it much harder for an attacker to corrupt objects on the
safe stack, including function pointers stored in spilled registers and
return addresses. You can find more information about the safe stack, as
well as other parts of or control-flow hijack protection technique in our
OSDI paper on code-pointer integrity (http://dslab.epfl.ch/pubs/cpi.pdf)
and our project website (http://levee.epfl.ch).
The overhead of our implementation of the safe stack is very close to zero
(0.01% on the Phoronix benchmarks). This is lower than the overhead of
stack cookies, which are supported by LLVM and are commonly used today,
yet the security guarantees of the safe stack are strictly stronger than
stack cookies. In some cases, the safe stack improves performance due to
better cache locality.
Our current implementation of the safe stack is stable and robust, we
used it to recompile multiple projects on Linux including Chromium, and
we also recompiled the entire FreeBSD user-space system and more than 100
packages. We ran unit tests on the FreeBSD system and many of the packages
and observed no errors caused by the safe stack. The safe stack is also fully
binary compatible with non-instrumented code and can be applied to parts of
a program selectively.
This patch is our implementation of the safe stack on top of LLVM. The
patches make the following changes:
- Add the safestack function attribute, similar to the ssp, sspstrong and
sspreq attributes.
- Add the SafeStack instrumentation pass that applies the safe stack to all
functions that have the safestack attribute. This pass moves all unsafe local
variables to the unsafe stack with a separate stack pointer, whereas all
safe variables remain on the regular stack that is managed by LLVM as usual.
- Invoke the pass as the last stage before code generation (at the same time
the existing cookie-based stack protector pass is invoked).
- Add unit tests for the safe stack.
Original patch by Volodymyr Kuznetsov and others at the Dependable Systems
Lab at EPFL; updates and upstreaming by myself.
Differential Revision: http://reviews.llvm.org/D6094
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239761 91177308-0d34-0410-b5e6-96231b3b80d8
This commit connects the machine function analysis pass (which creates machine
functions) to the MIR parser, which will initialize the machine functions
with the state from the MIR file and reconstruct the machine IR.
This commit introduces a new interface called 'MachineFunctionInitializer',
which can be used to provide custom initialization for the machine functions.
This commit also introduces a new diagnostic class called
'DiagnosticInfoMIRParser' which is used for MIR parsing errors.
This commit modifies the default diagnostic handling in LLVMContext - now the
the diagnostics are printed directly into llvm::errs() so that the MIR parsing
errors can be printed with colours.
Reviewers: Justin Bogner
Differential Revision: http://reviews.llvm.org/D9928
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239753 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
NFC: no one uses AnalyzeBranchPredicate yet.
Add TargetInstrInfo::AnalyzeBranchPredicate and implement for x86. A
later change adding support for page-fault based implicit null checks
depends on this.
Reviewers: reames, ab, atrick
Reviewed By: atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10200
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239742 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
TargetInstrInfo::getLdStBaseRegImmOfs to
TargetInstrInfo::getMemOpBaseRegImmOfs and implement for x86. The
implementation only handles a few easy cases now and will be made more
sophisticated in the future.
This is NFCI: the only user of `getLdStBaseRegImmOfs` (now
`getmemOpBaseRegImmOfs`) is `LoadClusterMotion` and `LoadClusterMotion`
is disabled for x86.
Reviewers: reames, ab, MatzeB, atrick
Reviewed By: MatzeB, atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10199
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239741 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This instruction encodes a loading operation that may fault, and a label
to branch to if the load page-faults. The locations of potentially
faulting loads and their "handler" destinations are recorded in a
FaultMap section, meant to be consumed by LLVM's clients.
Nothing generates FAULTING_LOAD_OP instructions yet, but they will be
used in a future change.
The documentation (FaultMaps.rst) needs improvement and I will update
this diff with a more expanded version shortly.
Depends on D10196
Reviewers: rnk, reames, AndyAyers, ab, atrick, pgavlin
Reviewed By: atrick, pgavlin
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10197
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239740 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This affects other tools so the previous C++ API has been retained as a
deprecated function for the moment. Clang has been updated with a trivial
patch (not covered by the pre-commit review) to avoid breaking -Werror builds.
Other in-tree tools will be fixed with similar trivial patches.
This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.
Reviewers: rengolin
Reviewed By: rengolin
Subscribers: llvm-commits, rengolin
Differential Revision: http://reviews.llvm.org/D10366
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239721 91177308-0d34-0410-b5e6-96231b3b80d8
StringSaver now always saves to a BumpPtrAllocator.
The only reason for having the virtual saveImpl is so lld can have a
thread safe version.
The reason for the distinct BumpPtrStringSaver class is to avoid the
virtual destructor.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239669 91177308-0d34-0410-b5e6-96231b3b80d8
r213101 changed the behaviour of this method to not only affect the
PostMachineScheduler scheduler but also the PostRAScheduler scheduler,
renaming should make this fact clear. Also document that the preferred
way is to specify this in the scheduling model instead of overriding
this method.
Differential Revision: http://reviews.llvm.org/D10427
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239659 91177308-0d34-0410-b5e6-96231b3b80d8
into partitions. Also, add an option to clone stub definitions (not just decls)
into partitions: these definitions could be inlined in some places to avoid the
overhead of calling via the stub.
Found by inspection - no test case yet, although I plan to add a unit test for
this once the CompileOnDemand layer refactoring settles down.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239640 91177308-0d34-0410-b5e6-96231b3b80d8
Based on ArchType, Clang's driver can select a non-Clang compiler.
String parsing in Clang would have sufficed if it were only that,
however this change anticipates true llvm support.
Differential Revision: http://reviews.llvm.org/D10413
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239631 91177308-0d34-0410-b5e6-96231b3b80d8
MCSymbol.h already forwards declares MCExpr and only uses MCExpr* so doesn't
need to include the header.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239626 91177308-0d34-0410-b5e6-96231b3b80d8
For hung off uses, we need a Use* to tell use where the operands are.
This was User::OperandList but we want to remove that to save space
of all subclasses which aren't making use of 'hung off uses'.
Hung off uses now allocate their own 'OperandList' Use* in the
User::new which they call.
getOperandList() now uses the hung off uses bit to work out where the
Use* for the OperandList lives. If a User has hung off uses, then this
bit tells them to go back a single Use* from the User* and use that
value as the OperandList.
If a User has no hung off uses, then we get the first operand by
subtracting (NumOperands * sizeof(Use)) from the User this pointer.
This saves a pointer from User and all subclasses. Given the average
size of a subclass of User is 112 or 128 bytes, this saves around 7% of space
With malloc tending to align to 16-bytes the real saving is typically more like 3.5%.
On 'opt -O2 verify-uselistorder.lto.bc', peak memory usage prior to this change
is 149MB and after is 143MB so the savings are around 2.5% of peak.
Looking at some passes which allocate many Instructions and Values, parseIR drops
from 54.25MB to 52.21MB while the Inliner calls to Instruction::clone() drops
from 28.20MB to 27.05MB.
Reviewed by Duncan Exon Smith.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239623 91177308-0d34-0410-b5e6-96231b3b80d8
There are now 2 versions of User::new. The first takes a size_t and is the current
implementation for subclasses which need 0 or more Use's allocated for their operands.
The new version takes no extra arguments to say that this subclass needs 'hung off uses'.
The HungOffUses bool is now set in this version of User::new and we can assert in
allocHungOffUses that we are allowed to have hung off uses.
This ensures we call the correct version of User::new for subclasses which need hung off uses.
A future commit will then allocate space for a single Use* which will be used
in place of User::OperandList once that field has been removed.
Reviewed by Duncan Exon Smith.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239622 91177308-0d34-0410-b5e6-96231b3b80d8
This is to try make it very clear that subclasses shouldn't be changing
the value directly. Now that OperandList for normal instructions is computed
using the NumOperands, its critical that the NumOperands is accurate or we
could compute the wrong offset to the first operand.
I looked over all places which update NumOperands and they are all safe.
Hung off use User's don't use NumOperands to compute the OperandList so they
are safe to continue to manipulate it. The only other User which changed it
was GlobalVariable which has an optional init list but always allocated space
for a single Use. It was correctly setting NumOperands to 1 before setting an
initializer, and setting it to 0 after clearing the init list, so the order was safe.
Added some comments to that code to make sure that this isn't changed in future
without being aware of this constraint.
Reviewed by Duncan Exon Smith.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239621 91177308-0d34-0410-b5e6-96231b3b80d8
We don't want anyone to access OperandList directly as its going to be removed
and computed instead. This uses getter's and setter's instead in which we
can later change the underlying implementation of OperandList.
Reviewed by Duncan Exon Smith.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239620 91177308-0d34-0410-b5e6-96231b3b80d8
The underlaying issues is that this code can't really know if an OS specific or
processor specific section number should return true or false.
One option would be to assert or return an error, but that looks like over
engineering since extensions are not that common.
It seems better to have these be direct implementation of the ELF spec so that
they are natural for someone familiar with ELF reading the code.
Code that does have to handle OS/Architecture specific values can do it at
a higher level.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239618 91177308-0d34-0410-b5e6-96231b3b80d8
This intrinsic is like framerecover plus a load. It recovers the EH
registration stack allocation from the parent frame and loads the
exception information field out of it, giving back a pointer to an
EXCEPTION_POINTERS struct. It's designed for clang to use in SEH filter
expressions instead of accessing the EXCEPTION_POINTERS parameter that
is available on x64.
This required a minor change to MC to allow defining a label variable to
another absolute framerecover label variable.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239567 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
For the moment, TargetMachine::getTargetTriple() still returns a StringRef.
This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.
Reviewers: rengolin
Reviewed By: rengolin
Subscribers: ted, llvm-commits, rengolin, jholewinski
Differential Revision: http://reviews.llvm.org/D10362
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239554 91177308-0d34-0410-b5e6-96231b3b80d8
This makes emitAbsoluteSymbolDiff always succeed and moves logic from the asm
printer to it.
The object one now also works on ELF. If two symbols are in the same fragment,
we will never move them apart.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239552 91177308-0d34-0410-b5e6-96231b3b80d8
It hasn't been used since r130964.
This also removes MachineModuleInfo::isUsedFunction and
MachineModuleInfo::AnalyzeModule, both of which were only
there to support UsedFunctions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239501 91177308-0d34-0410-b5e6-96231b3b80d8
This always just set the User::OperandList which is now set
in that method instead of being returned.
Reviewed by Duncan Exon Smith.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239493 91177308-0d34-0410-b5e6-96231b3b80d8
PhiNode, SwitchInst, LandingPad and IndirectBr all had virtually identical
logic for growing the hung off uses.
Move it to User so that they can all call a single shared implementation.
Their destructors were all empty after this change and were deleted. They all
have virtual clone_impl methods which can be used as vtable anchors.
Reviewed by Duncan Exon Smith.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239492 91177308-0d34-0410-b5e6-96231b3b80d8
Now that the subclasses which care about hung off uses let ~User clean it up,
there's no need for a separate method. Just inline it to ~User and delete it.
Reviewed by Duncan Exon Smith.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239491 91177308-0d34-0410-b5e6-96231b3b80d8
Currently all of the logic for deleting hung off uses, which PHI/switch/etc use,
is in their classes.
This adds a bit to Value which tracks whether that user had hung off uses,
then User can be responsible for clearing them instead of the sub classes.
Note, the bit used here was taken from NumOperands which was 30-bits.
Given the reduction to 29 bits, and the average User being just over 100 bytes,
a single User with 29-bits of num operands would need 50GB of RAM for itself
so its reasonable to assume that 29-bits is enough for now.
This is a step towards hiding all the hung off uses logic in the User.
Reviewed by Duncan Exon Smith.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239490 91177308-0d34-0410-b5e6-96231b3b80d8
PhiNode's need to allocate space for an array of Use[N] and then BasicBlock*[N].
They had their own allocHungOffUses to handle all of this. This moves the logic
in to User::allocHungOffUses and PhiNode passes in a bool to say to allocate
the BB* space too.
Reviewed by Duncan Exon Smith.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239489 91177308-0d34-0410-b5e6-96231b3b80d8
O2 compiles just before GlobalDCE, unless we are preparing for LTO.
This pass eliminates available externally globals (turning them into
declarations), regardless of whether they are dead/unreferenced, since
we are guaranteed to have a copy available elsewhere at link time.
This enables additional opportunities for GlobalDCE.
If we are preparing for LTO (e.g. a -flto -c compile), the pass is not
included as we want to preserve available externally functions for possible
link time inlining. The FE indicates whether we are doing an -flto compile
via the new PrepareForLTO flag on the PassManagerBuilder.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239480 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.
Reviewers: rafael
Reviewed By: rafael
Subscribers: rafael, ted, jfb, llvm-commits, rengolin, jholewinski
Differential Revision: http://reviews.llvm.org/D10311
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239467 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.
Reviewers: rafael
Reviewed By: rafael
Subscribers: rafael, llvm-commits, rengolin
Differential Revision: http://reviews.llvm.org/D10307
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239465 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.
Reviewers: echristo, rafael
Reviewed By: rafael
Subscribers: rafael, llvm-commits, rengolin
Differential Revision: http://reviews.llvm.org/D10243
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239464 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit 2e449ec5bcdf67b52b315b16c2128aaf25d5b73c.
This was svn r239440. Its currently failing an ARM test so reverting while I work out
what to do next.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239441 91177308-0d34-0410-b5e6-96231b3b80d8
It wasn't possible to have a variable Symbol with offset or 'isCommon' so
this just enables better packing of the MCSymbol class.
Reviewed by Rafael Espindola.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239440 91177308-0d34-0410-b5e6-96231b3b80d8
This gets all the handler info through to the asm printer and we can
look at the .xdata tables now. I've convinced one small catch-all test
case to work, but other than that, it would be a stretch to say this is
functional.
The state numbering algorithm avoids doing any scope reconstruction as
we do for C++ to simplify the implementation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239433 91177308-0d34-0410-b5e6-96231b3b80d8
Based on feedback to r239428 by David Blaikie, use const_cast to reduce
duplication of the const and non-const versions of getNameEntryPtr.
Also have that method return the pointer to the name directly instead
of users having to then get the name from the union.
Finally, add a FIXME that we should use a static_assert once available in
the new operator.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239429 91177308-0d34-0410-b5e6-96231b3b80d8
This should hopefully fix the 32-bit bots which were allocating space for a pointer
but needed to be aligned to 64-bits.
Now we allocate enough space for a uint64_t and a pointer and cast to the appropriate storage
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239428 91177308-0d34-0410-b5e6-96231b3b80d8
that was resetting it.
Remove the uses of DisableTailCalls in subclasses of TargetLowering and use
the value of function attribute "disable-tail-calls" instead. Also,
unconditionally add pass TailCallElim to the pipeline and check the function
attribute at the start of runOnFunction to disable the pass on a per-function
basis.
This is part of the work to remove TargetMachine::resetTargetOptions, and since
DisableTailCalls was the last non-fast-math option that was being reset in that
function, we should be able to remove the function entirely after the work to
propagate IR-level fast-math flags to DAG nodes is completed.
Out-of-tree users should remove the uses of DisableTailCalls and make changes
to attach attribute "disable-tail-calls"="true" or "false" to the functions in
the IR.
rdar://problem/13752163
Differential Revision: http://reviews.llvm.org/D10099
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239427 91177308-0d34-0410-b5e6-96231b3b80d8
Similarly to User which allocates a number of Use's prior to the this pointer,
allocate space for the Name* for MCSymbol only when we need a name.
Given that an MCSymbol is 48-bytes on 64-bit systems, this saves a decent % of space.
Given the verify_uselistorder test case with debug info and llc, 50k symbols have names
out of 700k so this optimises for the common case of temporary unnamed symbols.
Reviewed by David Blaikie.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239423 91177308-0d34-0410-b5e6-96231b3b80d8
make_error_code(object_error) is slow because object::object_category()
uses a ManagedStatic variable. But the real problem is that the function is
called too frequently. This patch uses std::error_code() instead of
object_error::success. In most cases, we return "success", so this patch
reduces number of function calls to that function.
http://reviews.llvm.org/D10333
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239409 91177308-0d34-0410-b5e6-96231b3b80d8
Specified the llvm namespace for the 2 calls to make_unique() which caused
compilation errors in Visual Studio 2013.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239405 91177308-0d34-0410-b5e6-96231b3b80d8
Fixes most of the test suite on Windows with clang-cl.
I'm not sure why the test suite was passing with MSVC 2013. Maybe they
changed their behavior and we are emulating their old sign extension
behavior. I think this deserves more investigation, but I want to green
the bot first.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239357 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This was a longstanding FIXME and is a necessary precursor to cases
where foldOperandImpl may have to create more than one instruction
(e.g. to constrain a register class). This is the split out NFC changes from
D6262.
Reviewers: pete, ributzka, uweigand, mcrosier
Reviewed By: mcrosier
Subscribers: mcrosier, ted, llvm-commits
Differential Revision: http://reviews.llvm.org/D10174
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239336 91177308-0d34-0410-b5e6-96231b3b80d8
on a per-function basis.
Previously some of the passes were conditionally added to ARM's pass pipeline
based on the target machine's subtarget. This patch makes changes to add those
passes unconditionally and execute them conditonally based on the predicate
functor passed to the pass constructors. This enables running different sets of
passes for different functions in the module.
rdar://problem/20542263
Differential Revision: http://reviews.llvm.org/D8717
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239325 91177308-0d34-0410-b5e6-96231b3b80d8
The Fragment and Section, and a bool for HasFragment were all used to create
a PointerUnion. Just use a pointer union instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239324 91177308-0d34-0410-b5e6-96231b3b80d8
All of ELF, COFF and MachO now manipulate the flags in helpers so we don't need
anyone to read the flags directly, but instead via those helpers.
Reviewed by Rafael Espíndola.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239317 91177308-0d34-0410-b5e6-96231b3b80d8
Also delete the now unused MCMachOSymbolFlags.h header as the only enum in there was moved to MCSymbolMachO.
Similarly to ELF and COFF, manipulating the flags is now done via helpers instead of spread
throughout the codebase.
Reviewed by Rafael Espíndola.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239316 91177308-0d34-0410-b5e6-96231b3b80d8
All flags setting/getting is now done in the class with helper methods instead
of users having to get the bits in the correct order.
Reviewed by Rafael Espíndola.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239314 91177308-0d34-0410-b5e6-96231b3b80d8
The flags field in MCSymbol only needs to be 16-bits on ELF and MachO.
This moves the 16-bit Type out of there so that it can be reduced in size in a future commit.
Reviewed by Rafael Espíndola.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239313 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
We need to add a runtime memcheck for pair of accesses (x,y) where at least one of x and y
are writes.
Assuming we have w writes and r reads, currently this number is estimated as being
w* (w+r-1). This estimation will count (write,write) pairs twice and will overestimate
the number of checks required.
This change adds a getNumberOfChecks method to RuntimePointerCheck, which
will count the number of runtime checks needed (similar in implementation to
needsAnyChecking) and uses it to produce the correct number of runtime checks.
Test Plan:
llvm test suite
spec2k
spec2k6
Performance results: no changes observed (not surprising since the formula for 1 writer is basically the same, which would covers most cases - at least with the current check limit).
Reviewers: anemet
Reviewed By: anemet
Subscribers: mzolotukhin, llvm-commits
Differential Revision: http://reviews.llvm.org/D10217
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239295 91177308-0d34-0410-b5e6-96231b3b80d8
Interleaved memory accesses are grouped and vectorized into vector load/store and shufflevector.
E.g. for (i = 0; i < N; i+=2) {
a = A[i]; // load of even element
b = A[i+1]; // load of odd element
... // operations on a, b, c, d
A[i] = c; // store of even element
A[i+1] = d; // store of odd element
}
The loads of even and odd elements are identified as an interleave load group, which will be transfered into vectorized IRs like:
%wide.vec = load <8 x i32>, <8 x i32>* %ptr
%vec.even = shufflevector <8 x i32> %wide.vec, <8 x i32> undef, <4 x i32> <i32 0, i32 2, i32 4, i32 6>
%vec.odd = shufflevector <8 x i32> %wide.vec, <8 x i32> undef, <4 x i32> <i32 1, i32 3, i32 5, i32 7>
The stores of even and odd elements are identified as an interleave store group, which will be transfered into vectorized IRs like:
%interleaved.vec = shufflevector <4 x i32> %vec.even, %vec.odd, <8 x i32> <i32 0, i32 4, i32 1, i32 5, i32 2, i32 6, i32 3, i32 7>
store <8 x i32> %interleaved.vec, <8 x i32>* %ptr
This optimization is currently disabled by defaut. To try it by adding '-enable-interleaved-mem-accesses=true'.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239291 91177308-0d34-0410-b5e6-96231b3b80d8
These were, originally, in a different form in lld.
They can be reused for other tools, e.g. llvm-readobj.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239231 91177308-0d34-0410-b5e6-96231b3b80d8
The new naming is (to me) much easier to understand. Here is a summary
of the new state of the world:
- '*Threshold' is the threshold for full unrolling. It is measured
against the estimated unrolled cost as computed by getUserCost in TTI
(or CodeMetrics, etc). We will exceed this threshold when unrolling
loops where unrolling exposes a significant degree of simplification
of the logic within the loop.
- '*PercentDynamicCostSavedThreshold' is the percentage of the loop's
estimated dynamic execution cost which needs to be saved by unrolling
to apply a discount to the estimated unrolled cost.
- '*DynamicCostSavingsDiscount' is the discount applied to the estimated
unrolling cost when the dynamic savings are expected to be high.
When actually analyzing the loop, we now produce both an estimated
unrolled cost, and an estimated rolled cost. The rolled cost is notably
a dynamic estimate based on our analysis of the expected execution of
each iteration.
While we're still working to build up the infrastructure for making
these estimates, to me it is much more clear *how* to make them better
when they have reasonably descriptive names. For example, we may want to
apply estimated (from heuristics or profiles) dynamic execution weights
to the *dynamic* cost estimates. If we start doing that, we would also
need to track the static unrolled cost and the dynamic unrolled cost, as
only the latter could reasonably be weighted by profile information.
This patch is sadly not without functionality change for the new unroll
analysis logic. Buried in the heuristic management were several things
that surprised me. For example, we never subtracted the optimized
instruction count off when comparing against the unroll heursistics!
I don't know if this just got lost somewhere along the way or what, but
with the new accounting of things, this is much easier to keep track of
and we use the post-simplification cost estimate to compare to the
thresholds, and use the dynamic cost reduction ratio to select whether
we can exceed the baseline threshold.
The old values of these flags also don't necessarily make sense. My
impression is that none of these thresholds or discounts have been tuned
yet, and so they're just arbitrary placehold numbers. As such, I've not
bothered to adjust for the fact that this is now a discount and not
a tow-tier threshold model. We need to tune all these values once the
logic is ready to be enabled.
Differential Revision: http://reviews.llvm.org/D9966
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239164 91177308-0d34-0410-b5e6-96231b3b80d8
These are added mainly for the benefit of clang, but this also means that they
are now allowed in .fpu directives and we emit the correct .fpu directive when
single-precision-only is used.
Differential Revision: http://reviews.llvm.org/D10238
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239151 91177308-0d34-0410-b5e6-96231b3b80d8
Add getFPUFeatures to TargetParser, which gets the list of subtarget features
that are enabled/disabled for each FPU, and use it when handling the .fpu
directive.
No functional change in this commit, though clang will start behaving
differently once it starts using this.
Differential Revision: http://reviews.llvm.org/D10237
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239150 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Only restoring AvailableFeatures is not enough and will lead to buggy behaviour.
For example, if we have a feature enabled and we ".set pop", the next time we try
to ".set" that feature nothing will happen because the "!(STI.getFeatureBits()[Feature])"
check will be false, because we didn't restore STI.FeatureBits.
In order to fix this, we need to make MipsAssemblerOptions remember the STI.FeatureBits
instead of the AvailableFeatures and then regenerate AvailableFeatures each time we ".set pop".
This is because, AFAIK, there is no way to convert from AvailableFeatures back to STI.FeatureBits,
but the reverse is possible by using ComputeAvailableFeatures(STI.FeatureBits).
I also moved the updating of AssemblerOptions inside the "if" statement in
setFeatureBits() and clearFeatureBits(), as there is no reason to update if
nothing changes.
Reviewers: dsanders, mkuper
Reviewed By: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9156
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239144 91177308-0d34-0410-b5e6-96231b3b80d8
When we generate coverage data, we explicitly set each coverage map's
alignment to 8 (See InstrProfiling::lowerCoverageData), but when we
read the coverage data, we assume consecutive maps are exactly
adjacent. When we're dealing with 32 bit, maps can end on a 4 byte
boundary, causing us to think the padding is part of the next record.
Fix this by adjusting the buffer to an appropriately aligned address
between records.
This is pretty awkward to test, as it requires a binary with multiple
coverage maps to hit, so we'd need to check in multiple source files
and a binary blob as inputs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239129 91177308-0d34-0410-b5e6-96231b3b80d8
Apparently this functionality isn't used in-tree (or I would go & make
the explicit unique_ptr constructions into implicit constructions to
make them more self documenting now that clone doesn't return a raw
owning pointer anymore) but only by the Julia frontend. This isn't
ideal.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239091 91177308-0d34-0410-b5e6-96231b3b80d8
Originally committed in r237975, GCC 4.7 gave a compilation error
regarding "looser throw specification" though it seemed to be pointing
to a virtual defaulted dtor in a base class and an override defaulted
dtor in a derived class - so I'm not quite sure why/how they could end
up with different throw specifications. To simplify and reduce the risk
of this, I've just removed the pointless override in the derived class,
the base class's should be sufficient. *fingers crossed*
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239088 91177308-0d34-0410-b5e6-96231b3b80d8
Now that we can look at users, we can trivially do this: when we would
have otherwise disabled GlobalMerge (currently -O<3), we can just run
it for minsize functions, as it's usually a codesize win.
Differential Revision: http://reviews.llvm.org/D10054
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239087 91177308-0d34-0410-b5e6-96231b3b80d8
Fix the FIXME and remove this old as(1) compat option. It was useful for
bringup of the integrated assembler to diff object files, but now it's
just causing more relocations than strictly necessary to be generated.
rdar://21201804
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239084 91177308-0d34-0410-b5e6-96231b3b80d8
I made a few changes here in a couple of commits - breaking them out
into smaller ones in case I hit the GCC oddities again.
I'm still not /entirely/ sure what the issues were, so apologies if any
of these experiments break things again. Feel free to revert
immediately.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239083 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Properly report the error in segment load commands from MachOObjectFile
constructor instead of crashing the program.
Adjust the test case accordingly.
Test Plan: regression test suite
Reviewers: rafael, filcab
Subscribers: llvm-commits
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239081 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Currently all load commands are parsed in MachOObjectFile constructor.
If the next load command cannot be parsed, or if command size is too
small, properly report it through the error code and fail to construct
the object, instead of crashing the program.
Test Plan: regression test suite
Reviewers: rafael, filcab
Subscribers: llvm-commits
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239080 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Avoid parsing object file each time MachOObjectFile::getHeader() is
called. Instead, cache the header in MachOObjectFile constructor, where
it's parsed anyway. In future, we must avoid constructing the object
at all if the header can't be parsed.
Test Plan: regression test suite.
Reviewers: rafael
Subscribers: llvm-commits
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239075 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
-march=bpf -> host endian
-march=bpf_le -> little endian
-match=bpf_be -> big endian
Test Plan:
v1 was tested by IBM s390 guys and appears to be working there.
It bit rots too fast here.
Reviewers: chandlerc, tstellarAMD
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10177
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239071 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This is the first of several patches to eliminate StringRef forms of GNU
triples from the internals of LLVM. After this is complete, GNU triples
will be replaced by a more authoratitive representation in the form of
an LLVM TargetTuple.
Reviewers: rengolin
Reviewed By: rengolin
Subscribers: ted, llvm-commits, rengolin, jholewinski
Differential Revision: http://reviews.llvm.org/D10236
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239036 91177308-0d34-0410-b5e6-96231b3b80d8
The fix is just that getOther had not been updated for packing the st_other
values in fewer bits and could return spurious values:
- unsigned Other = (getFlags() & (0x3f << ELF_STO_Shift)) >> ELF_STO_Shift;
+ unsigned Other = (getFlags() & (0x7 << ELF_STO_Shift)) >> ELF_STO_Shift;
Original message:
Pack the MCSymbolELF bit fields into MCSymbol's Flags.
This reduces MCSymolfELF from 64 bytes to 56 bytes on x86_64.
While at it, also make getOther/setOther easier to use by accepting unshifted
STO_* values.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239012 91177308-0d34-0410-b5e6-96231b3b80d8
This reduces MCSymolfELF from 64 bytes to 56 bytes on x86_64.
While at it, also make getOther/setOther easier to use by accepting unshifted
STO_* values.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239006 91177308-0d34-0410-b5e6-96231b3b80d8
port it to the new pass manager.
All this does is extract the inner "location" class used by AA into its
own full fledged type. This seems *much* cleaner as MemoryDependence and
soon MemorySSA also use this heavily, and it doesn't make much sense
being inside the AA infrastructure.
This will also make it much easier to break apart the AA infrastructure
into something that stands on its own rather than using the analysis
group design.
There are a few places where this makes APIs not make sense -- they were
taking an AliasAnalysis pointer just to build locations. I'll try to
clean those up in follow-up commits.
Differential Revision: http://reviews.llvm.org/D10228
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239003 91177308-0d34-0410-b5e6-96231b3b80d8
The first try (r238051) to land this was reverted due to ExecutionEngine build failure;
that was hopefully addressed by r238788.
The second try (r238842) to land this was reverted due to BUILD_SHARED_LIBS failure;
that was hopefully addressed by r238953.
This patch adds a TargetRecip class for processing many recip codegen possibilities.
The class is intended to handle both command-line options to llc as well
as options passed in from a front-end such as clang with the -mrecip option.
The x86 backend is updated to use the new functionality.
Only -mcpu=btver2 with -ffast-math should see a functional change from this patch.
All other x86 CPUs continue to *not* use reciprocal estimates by default with -ffast-math.
Differential Revision: http://reviews.llvm.org/D8982
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239001 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Now users don't have to manually deal with getFirstLoadCommandInfo() /
getNextLoadCommandInfo(), calculate the number of load segments, etc.
No functionality change.
Test Plan: regression test suite
Reviewers: rafael, lhames, loladiro
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10144
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238983 91177308-0d34-0410-b5e6-96231b3b80d8
This avoids yet another last minute patching of the binding.
While at it, also simplify the weakref implementation a bit by not walking
past it in the expression evaluation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238982 91177308-0d34-0410-b5e6-96231b3b80d8
With this getBinging can now return the correct answer for all cases not
involving a .symver and the elf writer doesn't need to patch it last minute.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238980 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
But still handle them the same way since I don't know how they differ on
this target.
Of these, /U[qytnms]/ do not have backend tests but are accepted by clang.
No functional change intended.
Reviewers: t.p.northover
Reviewed By: t.p.northover
Subscribers: t.p.northover, aemerson, llvm-commits
Differential Revision: http://reviews.llvm.org/D8203
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238921 91177308-0d34-0410-b5e6-96231b3b80d8
The ELF spec is very clear:
-----------------------------------------------------------------------------
If the value is non-zero, it represents a string table index that gives the
symbol name. Otherwise, the symbol table entry has no name.
--------------------------------------------------------------------------
In particular, a st_name of 0 most certainly doesn't mean that the symbol has
the same name as the section.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238899 91177308-0d34-0410-b5e6-96231b3b80d8
Some temporary symbols are created by MC itself. These symbols are never used
for lookup and are never included in the object symbol table, so we can
avoid creating a name for them.
Other temporaries are created by CodeGen or by the user by explicitly asking
for a name starting with .L (or L on MachO).
These temporaries behave like regular symbols, we just try to avoid including
them in the object symbol table, but sometimes they end up there:
const char *foo() {
return "abc" + 3;
}
will have a relocation pointing to a .L symbol.
It just so happens that almost all MC created temporary has the AlwaysAddSuffix
option and CodeGen/user created ones don't.
One interesting future optimization would be to use unnamed symbols for
all temporaries, but that would require use an st_name of 0 or
having the object writer create the names if a symbol does end up in the
symbol table.
No testcase since this just avoid creating a few extra names for MC created
temporaries.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238887 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
A later change that has RewriteStatepointsForGC change function
attributes throughout the module depends on this.
Reviewers: reames, pgavlin
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10104
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238882 91177308-0d34-0410-b5e6-96231b3b80d8
Now that we have a dedicated type for ELF symbol, these helper functions can
become member function of MCSymbolELF.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238864 91177308-0d34-0410-b5e6-96231b3b80d8
The first try (r238051) to land this was reverted due to bot failures
that were hopefully addressed by r238788.
This patch adds a TargetRecip class for processing many recip codegen possibilities.
The class is intended to handle both command-line options to llc as well
as options passed in from a front-end such as clang with the -mrecip option.
The x86 backend is updated to use the new functionality.
Only -mcpu=btver2 with -ffast-math should see a functional change from this patch.
All other x86 CPUs continue to *not* use reciprocal estimates by default with -ffast-math.
Differential Revision: http://reviews.llvm.org/D8982
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238842 91177308-0d34-0410-b5e6-96231b3b80d8
This create a MCSymbolELF class and moves SymbolSize since only ELF
needs a size expression.
This reduces the size of MCSymbol from 56 to 48 bytes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238801 91177308-0d34-0410-b5e6-96231b3b80d8
This allows us to extract version numbers from the environment.
getOSVersion is currently overloaded for that purpose, this allows us to
clean it up.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238796 91177308-0d34-0410-b5e6-96231b3b80d8
LLVMContext. Production builds of clang do not set names on most
Value's, so this is wasted space on almost all subclasses of Value.
This reduces the size of all Value subclasses by 8 bytes on 64 bit
hosts.
The one tricky part of this change is averting compile time regression
by keeping Value::hasName() fast. This required stealing bits out of
NumOperands.
With this change, peak memory usage on verify-uselistorder-nodbg.lto.bc
is decreased by approximately 2.3% (~3MB absolute on my machine).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238791 91177308-0d34-0410-b5e6-96231b3b80d8
If a dead instruction we may not only have a last-use in the main live
range but also in a subregister range if subregisters are tracked. We
need to partially rebuild live ranges in both cases.
The testcase only broke when subregister liveness was enabled. I
commited it in the current form because there is currently no flag to
enable/disable subregister liveness.
This fixes PR23720.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238785 91177308-0d34-0410-b5e6-96231b3b80d8
Start using C++ types such as StringRef and MemoryBuffer in the C++ LTO
API. In doing so, clarify the ownership of the native object file: the caller
now owns it, not the LTOCodeGenerator. The C libLTO library has been modified
to use a derived class of LTOCodeGenerator that owns the object file.
Differential Revision: http://reviews.llvm.org/D10114
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238776 91177308-0d34-0410-b5e6-96231b3b80d8
According to the TBAA description struct-path tag node can have an optional IsConstant field. Add corresponding argument to MDBuilder::createTBAAStructTagNode.
Reviewed By: hfinkel
Differential Revision: http://reviews.llvm.org/D10160
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238749 91177308-0d34-0410-b5e6-96231b3b80d8
This is important because of different addressing modes
depending on the address space for GPU targets.
This only adds the argument, and does not update
any of the uses to provide the correct address space.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238723 91177308-0d34-0410-b5e6-96231b3b80d8
Alternatively, this type could be derived on-demand whenever
getResultElementType is called - if someone thinks that's the better
choice (simple time/space tradeoff), I'm happy to give it a go.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238716 91177308-0d34-0410-b5e6-96231b3b80d8
There is no MCSectionData, so the old name is now meaningless.
Also remove some asserts/checks that were there just because the information
they used was in MCSectionData.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238708 91177308-0d34-0410-b5e6-96231b3b80d8
Unreachable values may use themselves in strange ways due to their
dominance property. Attempting to translate through them can lead to
infinite recursion, crashing LLVM. Instead, claim that we weren't able
to translate the value.
This fixes PR23096.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238702 91177308-0d34-0410-b5e6-96231b3b80d8
This fixes a bug in the line info handling in the dwarf code, based on a
problem I when implementing RelocVisitor support for MachO.
Since addr+size will give the first address past the end of the function,
we need to back up one line table entry. Fix this by looking up the
end_addr-1, which is the last address in the range. Note that this also
removes a duplicate output from the llvm-rtdyld line table dump. The
relevant line is the end_sequence one in the line table and has an offset
of the first address part the end of the range and hence should not be
included.
Also factor out the common functionality into a separate function.
This comes up on MachO much more than on ELF, since MachO
doesn't store the symbol size separately, hence making
said situation always occur.
Differential Revision: http://reviews.llvm.org/D9925
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238699 91177308-0d34-0410-b5e6-96231b3b80d8
This commit adds partial support for MachO relocations to RelocVisitor.
A simple test case is added to show that relocations are indeed being
applied and that using llvm-dwarfdump on MachO files no longer errors.
Correctness is not yet tested, due to an unrelated bug in DebugInfo,
which will be fixed with appropriate testcase in a followup commit.
Differential Revision: http://reviews.llvm.org/D8148
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238663 91177308-0d34-0410-b5e6-96231b3b80d8