Summary:
Sometimes, bitsets could get really large (>300k entries) and
we might want to drop a check, as it would have a too much cost.

Adding a flag to control how much penalty are we willing to pay
for bitsets.

Reviewers: kcc

Differential Revision: https://reviews.llvm.org/D23088

llvm-svn: 277556

Added ability to estimate the entry count of the extracted function and
the branch probabilities of the exit branches.

Patch by River Riddle!

Differential Revision: https://reviews.llvm.org/D22744

llvm-svn: 277411

[ADT] NFC: Generalize GraphTraits requirement of "NodeType *" in interfaces to "NodeRef", and migrate SCCIterator.h to use NodeRef

Summary: By generalize the interface, users are able to inject more flexible Node token into the algorithm, for example, a pair of vector<Node>* and index integer. Currently I only migrated SCCIterator to use NodeRef, but more is coming. It's a NFC.

Reviewers: dblaikie, chandlerc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D22937

llvm-svn: 277399

Summary: This patch implements CFI for WebAssembly. It modifies the
LowerTypeTest pass to pre-assign table indexes to functions that are
called indirectly, and lowers type checks to test against the
appropriate table indexes. It also modifies the WebAssembly backend to
support a special ".indidx" assembly directive that propagates the table
index assignments out to the linker.

Patch by Dominic Chen

Differential Revision: https://reviews.llvm.org/D21768

llvm-svn: 277398

They seem to trigger an LSan failure:
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/15140/steps/check-llvm%20asan/logs/stdio

Revert "Add the tests for r277313"

This reverts commit r277314.

Revert "CodeExtractor : Add ability to preserve profile data."

This reverts commit r277313.

llvm-svn: 277317

Added ability to estimate the entry count of the extracted function and
the branch probabilities of the exit branches.

Patch by River Riddle!

Differential Revision: https://reviews.llvm.org/D22744

llvm-svn: 277313

A ConstantVector can have ConstantExpr operands and vice versa.
However, the folder had no ability to fold ConstantVectors which, in
some cases, was an optimization barrier.

Instead, rephrase the folder in terms of Constants instead of
ConstantExprs and teach callers how to deal with failure.

llvm-svn: 277099

Summary:
copypasta doc of ImportedFunctionsInliningStatistics class
 \brief Calculate and dump ThinLTO specific inliner stats.
 The main statistics are:
 (1) Number of inlined imported functions,
 (2) Number of imported functions inlined into importing module (indirect),
 (3) Number of non imported functions inlined into importing module
 (indirect).
 The difference between first and the second is that first stat counts
 all performed inlines on imported functions, but the second one only the
 functions that have been eventually inlined to a function in the importing
 module (by a chain of inlines). Because llvm uses bottom-up inliner, it is
 possible to e.g. import function `A`, `B` and then inline `B` to `A`,
 and after this `A` might be too big to be inlined into some other function
 that calls it. It calculates this statistic by building graph, where
 the nodes are functions, and edges are performed inlines and then by marking
 the edges starting from not imported function.

 If `Verbose` is set to true, then it also dumps statistics
 per each inlined function, sorted by the greatest inlines count like
 - number of performed inlines
 - number of performed inlines to importing module

Reviewers: eraman, tejohnson, mehdi_amini

Subscribers: mehdi_amini, llvm-commits

Differential Revision: https://reviews.llvm.org/D22491

llvm-svn: 277089

The EP_CGSCCOptimizerLate extension point allows adding CallGraphSCC
passes at the end of the main CallGraphSCC passes and before any
function simplification passes run by CGPassManager.

Patch by Gor Nishanov!

Differential Revision: https://reviews.llvm.org/D22897

llvm-svn: 276953

Modify the variable names and code style to be that of modern LLVM.

Patch by River Riddle!

Differential Revision: https://reviews.llvm.org/D22743

llvm-svn: 276610

The public InlineFunction utility assumes that the passed in
InlineFunctionInfo has a valid AssumptionCacheTracker.

Patch by River Riddle!

Differential Revision: https://reviews.llvm.org/D22706

llvm-svn: 276609

Patch by Jake VanAdrighem

Differential Revision: http://reviews.llvm.org/D22607

llvm-svn: 276516

This unblocks the new PM part of River's patch in
https://reviews.llvm.org/D22706

Conveniently, this same change was needed for D21921 and so these
changes are just spun out from there.

llvm-svn: 276515

Summary:
Adding a flag to diable GVN Hoisting by default.
Note: The GVN Hoist Pass causes some Halide tests to hang. Halide will disable the pass while investigating.

Reviewers: llvm-commits, chandlerc, spop, dberlin

Subscribers: mehdi_amini

Differential Revision: https://reviews.llvm.org/D22639

llvm-svn: 276479

Just because we can constant fold the result of an instruction does not
imply that we can delete the instruction.  It may have side effects.

This fixes PR28655.

llvm-svn: 276389

llvm-svn: 276205

We skipped over ReturnInsts which didn't return an argument which would
lead us to incorrectly conclude that an argument returned by another
ReturnInst was 'returned'.

This reverts commit r275756.

This fixes PR28610.

llvm-svn: 276008

Summary: Port FunctionImport Pass to new PM.

Reviewers: mehdi_amini, davide

Subscribers: davidxl, llvm-commits

Differential Revision: https://reviews.llvm.org/D22475

llvm-svn: 275916

This reverts also r275029, "Update Clang tests after adding inference for the returned argument attribute"

It broke LTO build. Seems miscompilation.

llvm-svn: 275756

Summary:
To enable profile-guided indirect call promotion in ThinLTO mode, we
simply add call graph edges for each profitable target from the profile
to the summaries, then the summary-guided importing will consider the
callee for importing as usual.

Also we need to enable the indirect call promotion pass creation in the
PassManagerBuilder when PerformThinLTO=true (we are in the ThinLTO
backend), so that the newly imported functions are considered for
promotion in the backends.

The IC promotion profiles refer to callees by GUID, which required
adding GUIDs to the per-module VST in bitcode (and assigning them
valueIds similar to how they are assigned valueIds in the combined
index).

Reviewers: mehdi_amini, xur

Subscribers: mehdi_amini, davidxl, llvm-commits

Differential Revision: http://reviews.llvm.org/D21932

llvm-svn: 275707

This reverts commit r275042; the initial commit triggered self-hosting failures
on ARM/AArch64. James Molloy identified the problematic backend code, which has
been disabled in r275677. Trying again...

Original commit message:

Let FuncAttrs infer the 'returned' argument attribute

A function can have one argument with the 'returned' attribute, indicating that
the associated argument is always the return value of the function. Add
FuncAttrs inference logic.

llvm-svn: 275678

This patch adds a selected set of cleanup passes including a pre-inline pass
before LLVM IR PGO instrumentation. The inline is only intended to apply those
obvious/trivial ones before instrumentation so that much less instrumentation
is needed to get better profiling information. This will drastically improve
the instrumented code performance for large C++ applications. Another benefit
is the context sensitive counts that can potentially improve the PGO
optimization.

Differential Revision: http://reviews.llvm.org/D21405

llvm-svn: 275588

This pass hoists duplicated computations in the program. The primary goal of
gvn-hoist is to reduce the size of functions before inline heuristics to reduce
the total cost of function inlining.

Pass written by Sebastian Pop, Aditya Kumar, Xiaoyu Hu, and Brian Rzycki.
Important algorithmic contributions by Daniel Berlin under the form of reviews.

Differential Revision: http://reviews.llvm.org/D19338

llvm-svn: 275561

llvm-svn: 275420

This pass hoists duplicated computations in the program. The primary goal of
gvn-hoist is to reduce the size of functions before inline heuristics to reduce
the total cost of function inlining.

Pass written by Sebastian Pop, Aditya Kumar, Xiaoyu Hu, and Brian Rzycki.
Important algorithmic contributions by Daniel Berlin under the form of reviews.

Differential Revision: http://reviews.llvm.org/D19338

llvm-svn: 275401

Summary:
It's useful to have some visibility about which call sites are devirtualized,
especially for debug purposes. Another use case is a regression test on the
application side (like, Chromium).

Reviewers: pcc

Differential Revision: http://reviews.llvm.org/D22252

llvm-svn: 275145

There's a little bit of churn in this patch because the initialization
mechanism is now shared between the old and the new PM. Other than
that, it's just a pretty mechanical translation.

llvm-svn: 275082

In preparation for porting this pass to the new PM (which has no
doInitialization()).

Differential Revision:  http://reviews.llvm.org/D22223

llvm-svn: 275074

Summary:
For sample-based PGO, using BFI to calculate callsite count is sometime not accurate. This is because with sampling based approach, if a callsite resides in a hot loop deeply nested in a bunch of cold branches, the callsite's BFI frequency would be inaccurately calculated due to lack of samples in the cold branch.

E.g.

if (A1 && A2 && A3 && ..... && A10) {
  for (i=0; i < 100000000; i++) {
    callsite();
  }
}

Assume that A1 to A100 are all 100% taken, and callsite has 1000 samples and thus is considerred hot. Because the loop's trip count is huge, it's normal that all branches outside the loop has no sample at all. As a result, we can only use static branch probability to derive the the frequency of the loop header. Assuming that static heuristic thinks each branch is 50% taken, then the count calculated from BFI will be 1/(2^10) of the actual value.

In order to get more accurate callsite count, we directly annotate the weight on the call instruction, and directly use it when checking callsite hotness.

Note that this mechanism can also be shared by instrumentation based callsite hotness analysis. The side benefit is that it breaks the dependency from Inliner to BFI as call count is embedded in the IR.

Reviewers: davidxl, eraman, dnovillo

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D22118

llvm-svn: 275073

Summary: Handle the case when there is only one incoming/outgoing edge for a visited basic block: use the block weight to adjust edge weight even when the edge has been visited before. This can help reduce inaccuracies introduced by incorrect basic block profile, as shown in the updated unittest.

Reviewers: davidxl, dnovillo

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D22180

llvm-svn: 275072

Reverting r275027 and r275033. These seem to cause miscompiles on the AArch64 buildbot.

llvm-svn: 275042

Suggested post-commit by David Majnemer on IRC (following-up on a pre-commit
review comment).

llvm-svn: 275033

A function can have one argument with the 'returned' attribute, indicating that
the associated argument is always the return value of the function. Add
FuncAttrs inference logic.

Differential Revision: http://reviews.llvm.org/D22202

llvm-svn: 275027

No functionality change intended.

llvm-svn: 274973

llvm-svn: 274962

Summary:
This way the metadata will be only generated when asserts enabled,
or when -enable-import-metadata specified

FIXED missing colon on requires.

Reviewers: tejohnson, eraman, mehdi_amini

Subscribers: mehdi_amini, llvm-commits

Differential Revision: http://reviews.llvm.org/D22167

llvm-svn: 274947

Reverting because of 17463
http://lab.llvm.org:8011/builders/clang-x86_64-linux-selfhost-modules/builds/17463

This reverts commit d20cb431bba2ba43b4c65a8556cff445bfefbb7c.

llvm-svn: 274946

Summary:
This way the metadata will be only generated when asserts enabled,
or when -enable-import-metadata specified

Reviewers: tejohnson, eraman, mehdi_amini

Subscribers: mehdi_amini, llvm-commits

Differential Revision: http://reviews.llvm.org/D22167

llvm-svn: 274938

Summary: As we will move to use uniformed hotness check in inliner, we do not need inline hints in SampleProfile pass any more.

Reviewers: dnovillo, davidxl

Subscribers: eraman, llvm-commits

Differential Revision: http://reviews.llvm.org/D19287

llvm-svn: 274918

Differential Revision:  http://reviews.llvm.org/D21357

llvm-svn: 274910