Adds the following switches:
1. --sample-profile-inline-replay-fallback/--cgscc-inline-replay-fallback: controls what the replay advisor does for inline sites that are not present in the replay. Options are:
1. Original: defers to original advisor
2. AlwaysInline: inline all sites not in replay
3. NeverInline: inline no sites not in replay
2. --sample-profile-inline-replay-format/--cgscc-inline-replay-format: controls what format should be generated to match against the replay remarks. Options are:
1. Line
2. LineColumn
3. LineDiscriminator
4. LineColumnDiscriminator
Adds support for negative inlining decisions. These are denoted by "will not be inlined into" as compared to the positive "inlined into" in the remarks.
All of these together with the previous `--sample-profile-inline-replay-scope/--cgscc-inline-replay-scope` allow tweaking in how to apply replay. In my testing, I'm using:
1. --sample-profile-inline-replay-scope/--cgscc-inline-replay-scope = Function to only replay on a function
2. --sample-profile-inline-replay-fallback/--cgscc-inline-replay-fallback = NeverInline since I'm feeding in only positive remarks to the replay system
3. --sample-profile-inline-replay-format/--cgscc-inline-replay-format = Line since I'm generating the remarks from DWARF information from GCC which can conflict quite heavily in column number compared to Clang
An alternative configuration could be to do Function, AlwaysInline, Line fallback with negative remarks which closer matches the final call-sites. Note that this can lead to unbounded inlining if a negative remark doesn't match/exist for one reason or another.
Updated various tests to cover the new switches and negative remarks
Testing:
ninja check-all
Reviewed By: wenlei, mtrofin
Differential Revision: https://reviews.llvm.org/D112040
The goal is to allow grafting an inline tree from Clang or GCC into a new compilation without affecting other functions. For GCC, we're doing this by extracting the inline tree from dwarf information and generating the equivalent remarks.
This allows easier side-by-side asm analysis and a trial way to see if a particular inlining setup provides benefits by itself.
Testing:
ninja check-all
Reviewed By: wenlei, mtrofin
Differential Revision: https://reviews.llvm.org/D110658
If another inlining session came after a ModuleInlinerWrapperPass, the
advisor alanysis would still be cached, but its Result would be cleared.
We need to clear both.
This addresses PR52118
Differential Revision: https://reviews.llvm.org/D111586
This also removes the need to disable the mandatory inlining phase in
tests.
In a departure from the previous remark, we don't output a 'cost' in
this case, because there's no such thing. We just report that inlining
happened because of the attribute.
Differential Revision: https://reviews.llvm.org/D110891
Bisecting and reducing opt pipelines that includes the
ModuleInlinerWrapperPass has turned out to be a bit problematic.
This is far from perfect (it still lacks information about inline
advisor params etc.), but it should give some kind of hint to what
the wrapped pipeline looks like when using -print-pipeline-passes.
Reviewed By: aeubanks, mtrofin
Differential Revision: https://reviews.llvm.org/D109878
In default pipelines the ModuleInlinerWrapperPass is adding the
InlinerPass to the pipeline twice, once due to MandatoryFirst (passing
true in the ctor) and then a second time with false as argument.
To make it possible to bisect and reduce opt test cases for this
part of the pipeline we need to be able to choose between the two
different variants of the InlinerPass when running opt. This patch is
changing 'inline' to a CGSCC_PASS_WITH_PARAMS in the PassRegistry,
making it possible run opt with both -passes=cgscc(inline) and
-passes=cgscc(inline<only-mandatory>).
Reviewed By: aeubanks, mtrofin
Differential Revision: https://reviews.llvm.org/D109877
In weird cases, the inliner will inline internal recursive functions,
sometimes causing them to have no more uses, in which case the
inliner will mark the function to be deleted. The function is
actually deleted after the call to
updateCGAndAnalysisManagerForCGSCCPass(). In
updateCGAndAnalysisManagerForCGSCCPass(), UR.UpdatedC may be set to
the SCC containing the function to be deleted. Then the inliner calls
CG.removeDeadFunction() which can cause that SCC to be deleted, even
though it's still stored in UR.UpdatedC.
We could potentially check in the wrappers/pass managers if UR.UpdatedC
is in UR.InvalidatedSCCs before doing anything with it, but it's safer
to do this as close to possible to the call to CG.removeDeadFunction()
to avoid issues with allocating a new SCC in the same address as
the deleted one.
It's hard to find a small test case since we need to have recursive
internal functions be reachable from non-internal functions, yet they
need to become non-recursive and not referenced by other functions when
inlined.
Similar to https://reviews.llvm.org/D106306.
Fixes PR50788.
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D106405
Just like intrinsics are not tracked for IFI.InlinedCalls, they should not be tracked for IFI.InlinedCallSites.
In the current top-of-tree this change is a NFC, but the full restrict patches (D68484) potentially trigger an read-after-free
if intrinsics are also added to the InlindeCallSites, due to a late optimization potentially removing some of the inlined intrinsics.
Also see https://lists.llvm.org/pipermail/llvm-dev/2021-July/151722.html for a discussion about the problem.
Reviewed By: aeubanks
Differential Revision: https://reviews.llvm.org/D105805
The patch templatize PriorityInlinerOrder so that it can accept any type priority metric.
Reviewed By: kazu
Differential Revision: https://reviews.llvm.org/D104972
This patch makes PriorityInlineOrder lazily updated.
The PriorityInlineOrder would lazily update the desirability of a call site if it's decreasing.
Reviewed By: kazu
Differential Revision: https://reviews.llvm.org/D104654
This patch adds an optional PriorityInlineOrder, which uses the heap to order inlining.
The callsite which size is smaller would have a higher priority.
Reviewed By: mtrofin
Differential Revision: https://reviews.llvm.org/D104028
This patch adds an optional PriorityInlineOrder, which uses the heap to order inlining.
The callsite which size is smaller would have a higher priority.
Reviewed By: mtrofin
Differential Revision: https://reviews.llvm.org/D104028
This patch abstract Calls in Inliner:run() to InlineOrder.
With this patch, it's possible to customize the inlining order,
e.g. use queue or priority queue.
Reviewed By: kazu
Differential Revision: https://reviews.llvm.org/D103315
This patch abstract Calls in Inliner:run() to InlineOrder.
With this patch, it's possible to customize the inlining order, i.e. use queue or priority queue.
Reviewed By: kazu
Differential Revision: https://reviews.llvm.org/D103315
Printing pass manager invocations is fairly verbose and not super
useful.
This allows us to remove DebugLogging from pass managers and PassBuilder
since all logging (aside from analysis managers) goes through
instrumentation now.
This has the downside of never being able to print the top level pass
manager via instrumentation, but that seems like a minor downside.
Reviewed By: ychen
Differential Revision: https://reviews.llvm.org/D101797
The ModulePassManager should already have taken care of all analysis
invalidation. Without this change, upcoming changes will cause more
invalidation than necessary.
Reviewed By: mtrofin
Differential Revision: https://reviews.llvm.org/D101320
This change leverages the work done in D83743 to replay in the SampleProfile inliner to also be used in the CGSCC inliner. NOTE: currently restricted to non-ML advisors only.
The added switch `-cgscc-inline-replay=<remarks file>` will replay the inlining decisions in that file where the remarks file is generated via `-Rpass=inline`. The aim here is to make it easier to analyze changes that would modify inlining heuristics to be separated from this behavior. Doing so allows easier examination of assembly and runtime behavior compared to the baseline rather than trying to dig through the large churn caused by inlining.
In LTO compilation, since inlining is done twice you can separately specify replay by passing the flag to the FE (`-cgscc-inline-replay=`) and to the linker (`-Wl,cgscc-inline-replay=`) with the remarks generated from their respective places.
Testing on mysqld by comparing the inline decisions between base (generates remarks.txt) and diff (replay using identical input/tools with remarks.txt) and examining the inlining sites with `diff` shows 14,000 mismatches out of 247,341 for a ~94% replay accuracy. I believe this gap can be narrowed further though for the general case we may never achieve full accuracy. For my personal use, this is close enough to be representative: I set the baseline as the one generated by the replay on identical input/toolset and compare that to my modified input/toolset using the same replay.
Testing:
ninja check-llvm
newly added test correctly replays CGSCC inlining decisions
Reviewed By: mtrofin, wenlei
Differential Revision: https://reviews.llvm.org/D94334
This reverts commit d97f776be5.
The original problem was due to build failures in shared lib builds. D95079
moved ImportedFunctionsInliningStatistics under Analysis, unblocking
this.
This is related to D94982. We want to call these APIs from the Analysis
component, so we can't leave them under Transforms.
Differential Revision: https://reviews.llvm.org/D95079
When using 2 InlinePass instances in the same CGSCC - one for other
mandatory inlinings, the other for the heuristic-driven ones - the order
in which the ImportedFunctionStats would be output-ed would depend on
the destruction order of the inline passes, which is not deterministic.
This patch moves the ImportedFunctionStats responsibility to the
InlineAdvisor to address this problem.
Differential Revision: https://reviews.llvm.org/D94982
Expanding from D94808 - we ensure the same InlineAdvisor is used by both
InlinerPass instances. The notion of mandatory inlining is moved into
the core InlineAdvisor: advisors anyway have to handle that case, so
this change also factors out that a bit better.
Differential Revision: https://reviews.llvm.org/D94825
Enable performing mandatory inlinings upfront, by reusing the same logic
as the full inliner, instead of the AlwaysInliner. This has the
following benefits:
- reduce code duplication - one inliner codebase
- open the opportunity to help the full inliner by performing additional
function passes after the mandatory inlinings, but before th full
inliner. Performing the mandatory inlinings first simplifies the problem
the full inliner needs to solve: less call sites, more contextualization, and,
depending on the additional function optimization passes run between the
2 inliners, higher accuracy of cost models / decision policies.
Note that this patch does not yet enable much in terms of post-always
inline function optimization.
Differential Revision: https://reviews.llvm.org/D91567
Previously the inliner did a bit of a hack by adding ref edges for all
new edges introduced by performing an inline before calling
updateCGAndAnalysisManagerForPass(). This was because
updateCGAndAnalysisManagerForPass() didn't handle new non-trivial call
edges.
This adds handling of non-trivial call edges to
updateCGAndAnalysisManagerForPass(). The inliner called
updateCGAndAnalysisManagerForFunctionPass() since it was handling adding
newly introduced edges (so updateCGAndAnalysisManagerForPass() would
only have to handle promotion), but now it needs to call
updateCGAndAnalysisManagerForCGSCCPass() since
updateCGAndAnalysisManagerForPass() is now handling the new call edges
and function passes cannot add new edges.
We follow the previous path of adding trivial ref edges then letting promotion
handle changing the ref edges to call edges and the CGSCC updates. So
this still does not allow adding call edges that result in an addition
of a non-trivial ref edge.
This is in preparation for better detecting devirtualization. Previously
since the inliner itself would add ref edges,
updateCGAndAnalysisManagerForPass() would think that promotion and thus
devirtualization had happened after any sort of inlining.
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D91046
An alwaysinline function may not get inlined in inliner-wrapper due to
the inlining order.
Previously for the following, the inliner would first inline @a() into @b(),
```
define void @a() {
entry:
call void @b()
ret void
}
define void @b() alwaysinline {
entry:
br label %for.cond
for.cond:
call void @a()
br label %for.cond
}
```
making @b() recursive and unable to be inlined into @a(), ending at
```
define void @a() {
entry:
call void @b()
ret void
}
define void @b() alwaysinline {
entry:
br label %for.cond
for.cond:
call void @b()
br label %for.cond
}
```
Running always-inliner first makes sure that we respect alwaysinline in more cases.
Fixes https://bugs.llvm.org/show_bug.cgi?id=46945.
Reviewed By: davidxl, rnk
Differential Revision: https://reviews.llvm.org/D86988
Previously the NPM inliner would skip all potential inlines in an
optnone function, but alwaysinline callees should be inlined regardless
of optnone.
Fixes inline-optnone.ll under NPM.
Reviewed By: kazu
Differential Revision: https://reviews.llvm.org/D83021
Summary:
This simplifies the interface by storing the function analysis manager
with the InlineAdvisor, and, thus, not requiring it be passed each time
we inquire for an advice.
Reviewers: davidxl, asbirlea
Subscribers: eraman, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D80405
Along the lines of D77454 and D79968. Unlike loads and stores, the
default alignment is getPrefTypeAlign, to match the existing handling in
various places, including SelectionDAG and InstCombine.
Differential Revision: https://reviews.llvm.org/D80044
This reverts commit 454de99a6f.
The problem was that one of the ctor arguments of CallAnalyzer was left
to be const std::function<>&. A function_ref was passed for it, and then
the ctor stored the value in a function_ref field. So a std::function<>
would be created as a temporary, and not survive past the ctor
invocation, while the field would.
Tested locally by following https://github.com/google/sanitizers/wiki/SanitizerBotReproduceBuild
Original Differential Revision: https://reviews.llvm.org/D79917
Summary:
Replacing uses of std::function pointers or refs, or Optional, to
function_ref, since the usage pattern allows that. If the function is
optional, using a default parameter value (nullptr). This led to a few
parameter reshufles, to push all optionals to the end of the parameter
list.
Reviewers: davidxl, dblaikie
Subscribers: arsenm, jvesely, nhaehnle, eraman, hiraditya, haicheng, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D79917
Summary:
This change introduces InliningAdvisor (and related APIs), the interface
that abstracts decision making away from the inlining pass. We will use
this interface to delegate decision making to a trained ML model,
subsequently (see referenced RFC).
RFC: http://lists.llvm.org/pipermail/llvm-dev/2020-April/140763.html
Reviewers: davidxl, eraman, dblaikie
Subscribers: mgorny, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D79042
Summary:
Analyses that are statefull should not be retrieved through a proxy from
an outer IR unit, as these analyses are only invalidated at the end of
the inner IR unit manager.
This patch disallows getting the outer manager and provides an API to
get a cached analysis through the proxy. If the analysis is not
stateless, the call to getCachedResult will assert.
Reviewers: chandlerc
Subscribers: mehdi_amini, eraman, hiraditya, zzheng, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D72893
Summary:
This patch teaches shouldBeDeferred to take into account the total
cost of inlining.
Suppose we have a call hierarchy {A1,A2,A3,...}->B->C. (Each of A1,
A2, A3, ... calls B, which in turn calls C.)
Without this patch, shouldBeDeferred essentially returns true if
TotalSecondaryCost < IC.getCost()
where TotalSecondaryCost is the total cost of inlining B into As.
This means that if B is a small wraper function, for example, it would
get inlined into all of As. In turn, C gets inlined into all of As.
In other words, shouldBeDeferred ignores the cost of inlining C into
each of As.
This patch adds an option, inline-deferral-scale, to replace the
expression above with:
TotalCost < Allowance
where
- TotalCost is TotalSecondaryCost + IC.getCost() * # of As, and
- Allowance is IC.getCost() * Scale
For now, the new option defaults to -1, disabling the new scheme.
Reviewers: davidxl
Subscribers: eraman, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D79138