reference-edge SCCs.
This essentially builds a more normal call graph as a subgraph of the
"reference graph" that was the old model. This allows both to exist and
the different use cases to use the aspect which addresses their needs.
Specifically, the pass manager and other *ordering* constrained logic
can use the reference graph to achieve conservative order of visit,
while analyses reasoning about attributes and other properties derived
from reachability can reason about the direct call graph.
Note that this isn't necessarily complete: it doesn't model edges to
declarations or indirect calls. Those can be found by scanning the
instructions of the function if desirable, and in fact every user
currently does this in order to handle things like calls to instrinsics.
If useful, we could consider caching this information in the call graph
to save the instruction scans, but currently that doesn't seem to be
important.
An important realization for why the representation chosen here works is
that the call graph is a formal subset of the reference graph and thus
both can live within the same data structure. All SCCs of the call graph
are necessarily contained within an SCC of the reference graph, etc.
The design is to build 'RefSCC's to model SCCs of the reference graph,
and then within them more literal SCCs for the call graph.
The formation of actual call edge SCCs is not done lazily, unlike
reference edge 'RefSCC's. Instead, once a reference SCC is formed, it
directly builds the call SCCs within it and stores them in a post-order
sequence. This is used to provide a consistent platform for mutation and
update of the graph. The post-order also allows for very efficient
updates in common cases by bounding the number of nodes (and thus edges)
considered.
There is considerable common code that I'm still looking for the best
way to factor out between the various DFS implementations here. So far,
my attempts have made the code harder to read and understand despite
reducing the duplication, which seems a poor tradeoff. I've not given up
on figuring out the right way to do this, but I wanted to wait until
I at least had the system working and tested to continue attempting to
factor it differently.
This also requires introducing several new algorithms in order to handle
all of the incremental update scenarios for the more complex structure
involving two edge colorings. I've tried to comment the algorithms
sufficiently to make it clear how this is expected to work, but they may
still need more extensive documentation.
I know that there are some changes which are not strictly necessarily
coupled here. The process of developing this started out with a very
focused set of changes for the new structure of the graph and
algorithms, but subsequent changes to bring the APIs and code into
consistent and understandable patterns also ended up touching on other
aspects. There was no good way to separate these out without causing
*massive* merge conflicts. Ultimately, to a large degree this is
a rewrite of most of the core algorithms in the LCG class and so I don't
think it really matters much.
Many thanks to the careful review by Sanjoy Das!
Differential Revision: http://reviews.llvm.org/D16802
llvm-svn: 261040
Add support for trimming a single kind of character from a StringRef.
This makes the common case of trimming null bytes much neater. It's also
probably a bit speedier too, since it avoids creating a std::bitset in
find_{first,last}_not_of.
llvm-svn: 260925
Summary:
Export the CloneDebugInfoMetadata utility, which clones all debug info
associated with a function into the first module. Also use this function
in CloneModule on each function we clone (the CloneFunction entrypoint
already does this).
Without this, cloning a module will lead to DI quality regressions,
especially since r252219 reversed the Function <-> DISubprogram edge
(before we could get lucky and have this edge preserved if the
DISubprogram itself was, e.g. due to location metadata).
This was verified to fix missing debug information in julia and
a unittest to verify the new behavior is included.
Patch by Yichao Yu! Thanks!
Reviewers: loladiro, pcc
Differential Revision: http://reviews.llvm.org/D17165
llvm-svn: 260791
As support expands to more runtimes, we'll need to
distinguish between more than just HSA and unknown.
This also lets us stop using unknown everywhere.
llvm-svn: 260790
Add another interface to function annotateValueSite() which directly uses the
VauleData array.
Differential Revision: http://reviews.llvm.org/D17108
llvm-svn: 260741
The patch adds a parameter in annotateValueSite() to control the max number
of records written to the value profile meta data for each value site. The
default is kept as the current value of 3.
Differential Revision: http://reviews.llvm.org/D17084
llvm-svn: 260450
Patch by Rong Xu
The problem is exposed by intra-module indirect call promotion where
prof symtab is created from module which does not contain all symbols
from the program. With partial symtab, the result needs to be checked
more strictly.
llvm-svn: 260361
This patch adds a new class, OrcI386, which contains the hooks needed to
support lazy-JITing on i386 (currently only for Pentium 2 or above, as the JIT
re-entry code uses the FXSAVE/FXRSTOR instructions).
Support for i386 is enabled in the LLI lazy JIT and the Orc C API, and
regression and unit tests are enabled for this architecture.
llvm-svn: 260338
This pass implements whole program optimization of virtual calls in cases
where we know (via bitset information) that the list of callees is fixed. This
includes the following:
- Single implementation devirtualization: if a virtual call has a single
possible callee, replace all calls with a direct call to that callee.
- Virtual constant propagation: if the virtual function's return type is an
integer <=64 bits and all possible callees are readnone, for each class and
each list of constant arguments: evaluate the function, store the return
value alongside the virtual table, and rewrite each virtual call as a load
from the virtual table.
- Uniform return value optimization: if the conditions for virtual constant
propagation hold and each function returns the same constant value, replace
each virtual call with that constant.
- Unique return value optimization for i1 return values: if the conditions
for virtual constant propagation hold and a single vtable's function
returns 0, or a single vtable's function returns 1, replace each virtual
call with a comparison of the vptr against that vtable's address.
Differential Revision: http://reviews.llvm.org/D16795
llvm-svn: 260312
compiler-specific issues. Instead, repeat an 'operator delete' definition in
each derived class that is actually deleted, and give up on the static type
safety of an error when sized delete is accidentally used on a type derived
from TrailingObjects.
llvm-svn: 260190
This fixes undefined behavior in C++14 due to the size of the object being
deleted being different from sizeof(dynamic type) when it is allocated with
trailing objects.
MSVC seems to have several bugs around using-declarations changing the access
of a member inherited from a base class, so use forwarding functions instead of
using-declarations to make TrailingObjects::operator delete accessible where
desired.
llvm-svn: 260180
Summary:
Unrolling Analyzer is already pretty complicated, and it becomes harder and harder to exercise it with usual IR tests, as with them we can only check the final decision: whether the loop is unrolled or not. This change factors this framework out from LoopUnrollPass to analyses, which allows to use unit tests.
The change itself is supposed to be NFC, except adding a couple of tests.
I plan to add more tests as I add new functionality and find/fix bugs.
Reviewers: chandlerc, hfinkel, sanjoy
Subscribers: zzheng, sanjoy, llvm-commits
Differential Revision: http://reviews.llvm.org/D16623
llvm-svn: 260169
The Windows bots have been failing for the last two days, with:
FAILED: C:\PROGRA~2\MICROS~1.0\VC\bin\amd64\cl.exe -c LLVMContextImpl.cpp
D:\buildslave\clang-x64-ninja-win7\llvm\lib\IR\LLVMContextImpl.cpp(137) :
error C2248: 'llvm::TrailingObjects<llvm::AttributeSetImpl,
llvm::IndexAttrPair>::operator delete' :
cannot access private member declared in class 'llvm::AttributeSetImpl'
TrailingObjects.h(298) : see declaration of
'llvm::TrailingObjects<llvm::AttributeSetImpl,
llvm::IndexAttrPair>::operator delete'
AttributeImpl.h(213) : see declaration of 'llvm::AttributeSetImpl'
llvm-svn: 260053
-fsized-deallocation. Disable sized deallocation for all objects derived from
TrailingObjects, as we expect the storage allocated for these objects to be
larger than the size of their dynamic type.
llvm-svn: 259942
Unfortunately, ProgramInfo::ProcessId is signed on Unix and unsigned on
Windows, breaking the standard fix of using '0U' in the gtest
expectation.
llvm-svn: 259704
With this patch, the profile summary data will be available in indexed
profile data file so that profiler reader/compiler optimizer can start
to make use of.
Differential Revision: http://reviews.llvm.org/D16258
llvm-svn: 259626
differentiate between indirect references to functions an direct calls.
This doesn't do a whole lot yet other than change the print out produced
by the analysis, but it lays the groundwork for a very major change I'm
working on next: teaching the call graph to actually be a call graph,
modeling *both* the indirect reference graph and the call graph
simultaneously. More details on that in the next patch though.
The rest of this is essentially a bunch of over-engineering that won't
be interesting until the next patch. But this also isolates essentially
all of the churn necessary to introduce the edge abstraction from the
very important behavior change necessary in order to separately model
the two graphs. So it should make review of the subsequent patch a bit
easier at the cost of making this patch seem poorly motivated. ;]
Differential Revision: http://reviews.llvm.org/D16038
llvm-svn: 259463
With poorly chosen custom parameters, the line table encoding logic would
sometimes end up generating a special opcode bigger than 255, which is wrong.
The set of default parameters that LLVM uses isn't subject to this bug.
When carefully chosing the line table parameters, it's impossible to fall into the
corner case that this patch fixes. The standard however doesn't require that these
parameters be carefully chosen. And even if it did, we shouldn't generate broken
encoding.
Add a unittest for this specific encoding bug, and while at it, create some unit
tests for the encoding logic using different sets of parameters.
llvm-svn: 259334
Add an option to llvm-profdata merge for writing out sparse indexed
profiles. These profiles omit InstrProfRecords for functions which are
never executed.
Differential Revision: http://reviews.llvm.org/D16727
llvm-svn: 259258
