Summary:
Improve SaturatingAdd()/SaturatingMultiply() to use bool * to optionally return overflow result.
This should make it clearer that the value is returned at callsites and reduces the size of the implementation.
Reviewers: davidxl, silvas
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15219
llvm-svn: 255128
Summary:
Available_externally global variable with initializer were considered "hasInitializer()",
while obviously it can't match the description:
Whether the global variable has an initializer, and any changes made to the
initializer will turn up in the final executable.
since modifying the initializer of an externally available variable does not make sense.
Reviewers: pcc, rafael
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15351
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 255123
ScalarEvolution.h, in order to avoid cyclic dependencies between the Transform
and Analysis modules:
[LV][LAA] Add a layer over SCEV to apply run-time checked knowledge on SCEV expressions
Summary:
This change creates a layer over ScalarEvolution for LAA and LV, and centralizes the
usage of SCEV predicates. The SCEVPredicatedLayer takes the statically deduced knowledge
by ScalarEvolution and applies the knowledge from the SCEV predicates. The end goal is
that both LAA and LV should use this interface everywhere.
This also solves a problem involving the result of SCEV expression rewritting when
the predicate changes. Suppose we have the expression (sext {a,+,b}) and two predicates
P1: {a,+,b} has nsw
P2: b = 1.
Applying P1 and then P2 gives us {a,+,1}, while applying P2 and the P1 gives us
sext({a,+,1}) (the AddRec expression was changed by P2 so P1 no longer applies).
The SCEVPredicatedLayer maintains the order of transformations by feeding back
the results of previous transformations into new transformations, and therefore
avoiding this issue.
The SCEVPredicatedLayer maintains a cache to remember the results of previous
SCEV rewritting results. This also has the benefit of reducing the overall number
of expression rewrites.
Reviewers: mzolotukhin, anemet
Subscribers: jmolloy, sanjoy, llvm-commits
Differential Revision: http://reviews.llvm.org/D14296
llvm-svn: 255122
Summary:
This change creates a layer over ScalarEvolution for LAA and LV, and centralizes the
usage of SCEV predicates. The SCEVPredicatedLayer takes the statically deduced knowledge
by ScalarEvolution and applies the knowledge from the SCEV predicates. The end goal is
that both LAA and LV should use this interface everywhere.
This also solves a problem involving the result of SCEV expression rewritting when
the predicate changes. Suppose we have the expression (sext {a,+,b}) and two predicates
P1: {a,+,b} has nsw
P2: b = 1.
Applying P1 and then P2 gives us {a,+,1}, while applying P2 and the P1 gives us
sext({a,+,1}) (the AddRec expression was changed by P2 so P1 no longer applies).
The SCEVPredicatedLayer maintains the order of transformations by feeding back
the results of previous transformations into new transformations, and therefore
avoiding this issue.
The SCEVPredicatedLayer maintains a cache to remember the results of previous
SCEV rewritting results. This also has the benefit of reducing the overall number
of expression rewrites.
Reviewers: mzolotukhin, anemet
Subscribers: jmolloy, sanjoy, llvm-commits
Differential Revision: http://reviews.llvm.org/D14296
llvm-svn: 255115
Summary:
The order of destructors in LTOCodeGenerator gets changed in r254696.
It is possible for LTOCodeGenerator to have a MergedModule created in
the OwnedContext, in which case the module must be destructed before
the context.
Reviewers: rafael, dexonsmith
Subscribers: llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D15346
llvm-svn: 255092
Per LangRef: "Globals with available_externally linkage are
allowed to be discarded at will, and are otherwise the same
as linkonce_odr", since linkonce_odr is in this list it makes
sense to have available_externally there as well.
Reviewers: rafael
Differential Revision: http://reviews.llvm.org/D15323
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 255043
The StringRef constructor is unnecessary (since we're converting to
std::string anyway), and having it requires an explicit call to
StringRef's or std::string's constructor.
llvm-svn: 255000
Summary:
Also add a stricter post-condition for IndVarSimplify.
Fixes PR25578. Test case by Michael Zolotukhin.
Reviewers: hfinkel, atrick, mzolotukhin
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15059
llvm-svn: 254977
Summary:
(Note: the problematic invocation of hoistIVInc that caused PR24804 came
from IndVarSimplify, not from SCEVExpander itself)
Fixes PR24804. Test case by David Majnemer.
Reviewers: hfinkel, majnemer, atrick, mzolotukhin
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15058
llvm-svn: 254976
We were using unneccessarily large initial sizes for these SmallVectors. This was wasting around 50kb of memory for the O3 pipeline, even after the uniquing changes. We're still using around 20kb which is a bit much, but it's definitely better. This is about a 6% improvement in total O3 memory usage.
Note: The raw data on structure size which were used to pick these thresholds can be found in the review thread.
Differential Revision: http://reviews.llvm.org/D15244
llvm-svn: 254974
This is supposed to force-link the Interpreter, by inserting a dead
call to LLVMLinkInInterpreter().
Since it is actually an empty function, there is no reason for the
call to be dead.
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 254956
Summary:
Add a field on the PassManagerBuilder that clang or gold can use to pass
down a pointer to the function index in memory to use for importing when
the ThinLTO backend is triggered. Add support to supply this to the
function import pass.
Reviewers: joker.eph, dexonsmith
Subscribers: davidxl, llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D15024
llvm-svn: 254926
This is needed to support linking of module-level metadata as a
postpass after function importing, where we will be leaving temporary
metadata on imported instructions until the postpass metadata import.
Also added unittest. Split from D14838.
llvm-svn: 254914
This removes the code path that generate "synchronous" (only correct at call site) CFA.
We will probably want to re-introduce it once we are capable of emitting different
.eh_frame and .debug_frame sections.
Differential Revision: http://reviews.llvm.org/D14948
llvm-svn: 254874
Summary:
There are `SelectPatternFlavor`s that don't represent min or max idioms,
and we should not be passing those to `getCmpPredicateForMinMax`.
Fixes PR25745.
Reviewers: majnemer
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15249
llvm-svn: 254869
Different version of indexed format may use different
name uniquing schemes for static functions. Pass the
version info to the name interface so that different
schmes can be picked (for profile lookup).
llvm-svn: 254838
The indexList's nodes are all allocated on a BumpPtrAllocator, so it's
more efficient to let them be freed when it goes away, rather than
deleting them directly. This is a follow up to r254794.
llvm-svn: 254808
When the notion of target specific memory intrinsics was introduced to EarlyCSE, the commit confused the notions of volatile and simple memory access. Since I'm about to start working on this area, cleanup the naming so that patches aren't horribly confusing. Note that the actual implementation was always bailing if the load or store wasn't simple.
Reminder:
- "volatile" - C++ volatile, can't remove any memory operations, but in principal unordered
- "ordered" - imposes ordering constraints on other nearby memory operations
- "atomic" - can't be split or sheared. In LLVM terms, all "ordered" operations are also atomic so the predicate "isAtomic" is often used.
- "simple" - a load which is none of the above. These are normal loads and what most of the optimizer works with.
llvm-svn: 254805
In 254760, I introduced the usage of a BumpPtrAllocator for the AnalysisUsage instances held by the PassManger. This turns out to have been incorrect since a BumpPtrAllocator does not run the destructors of objects when deallocating memory. Since a few of our SmallVector's had grown beyond their small size, we end up with some leaked memory. We need to use a SpecificBumpPtrAllocator instead.
llvm-svn: 254803
The issue appears to have been that the copy constructor of the SmallVector was being invoked and this was somehow leading to leaked memory. This patch avoids the symptom, but likely doesn't address the underlying problem. I'm still investigating the root cause, but wanted to avoid the memory leak in the mean time. Even with the underlying fix, avoiding the redundant allocation is worthwhile.
llvm-svn: 254795
When a `SlotIndexes` is destroyed, `ileAllocator` will currently be
destructed before `IndexList`, but all of `IndexList`'s storage has
been allocated by `ileAllocator`. This means we'll call destructors on
garbage data, which is very bad. This can be avoided by putting the
BumpPtrAllocator earlier in the class than anything it allocates.
Unfortunately, I don't know how to test this. It depends very much on
memory layout, and the only evidence I have that this is actually
happening in practice are backtraces that might be explained by this.
By inspection though, the code is obviously dangerous/wrong, and this
is the right thing to do.
I'll follow up later with a patch that calls clearAndLeakNodesUnsafely
on the list, since there isn't much point in destructing them when
they're allocated in a BPA anyway, but I figured it makes sense to
commit the correctness fix separately from that optimization.
llvm-svn: 254794
Before this patch the diagnostic handler was optional. If it was not
passed, the one in the LLVMContext was used.
That is probably not a pattern we want to follow. If each area has an
optional callback, there is a sea of callbacks and it is hard to follow
which one is called.
Doing this also found cases where the callback is a nice addition, like
testing that no errors or warnings are reported.
The other option is to always use the diagnostic handler in the
LLVMContext. That has a few problems
* To implement the C API we would have to set the diag handler and then
set it back to the original value.
* Code that creates the context might be far away from code that wants
the diagnostics.
I do have a patch that implements the second option and will send that as
an RFC.
llvm-svn: 254777
Currently `OperandBundleUse::operandsHaveAttr` computes its result
without being given a specific operand. This is problematic because it
forces us to say that, e.g., even non-pointer operands in `"deopt"`
operand bundles are `readonly`, which doesn't make sense.
This commit changes `operandsHaveAttr` to work in the context of a
specific operand, so that we can give the operand attributes that make
sense for the operands's `llvm::Type`.
llvm-svn: 254764
The LegacyPassManager was storing an instance of AnalysisUsage for each instance of each pass. In practice, most instances of a single pass class share the same dependencies. We can't rely on this because passes can (and some do) have dynamic dependencies based on instance options.
We can exploit the likely commonality by uniqueing the usage information after querying the pass, but before storing it into the pass manager. This greatly reduces memory consumption by the AnalysisUsage objects. For a long pass pipeline, I measured a decrease in memory consumption for this storage of about 50%. I have not measured on the default O3 pipeline, but I suspect it will see some benefit as well since many passes are repeated (e.g. InstCombine).
Differential Revision: http://reviews.llvm.org/D14677
llvm-svn: 254760
Nathan Slingerland