[WPD] Use new llvm.public.type.test intrinsic for potentially publicly visible classes

Turning on opaque pointers has uncovered an issue with WPD where we currently pattern match away `assume(type.t

[WPD] Use new llvm.public.type.test intrinsic for potentially publicly visible classes

Turning on opaque pointers has uncovered an issue with WPD where we currently pattern match away `assume(type.test)` in WPD so that a later LTT doesn't resolve the type test to undef and introduce an `assume(false)`. The pattern matching can fail in cases where we transform two `assume(type.test)`s into `assume(phi(type.test.1, type.test.2))`.

Currently we create `assume(type.test)` for all virtual calls that might be devirtualized. This is to support `-Wl,--lto-whole-program-visibility`.

To prevent this, all virtual calls that may not be in the same LTO module instead use a new `llvm.public.type.test` intrinsic in place of the `llvm.type.test`. Then when we know if `-Wl,--lto-whole-program-visibility` is passed or not, we can either replace all `llvm.public.type.test` with `llvm.type.test`, or replace all `llvm.public.type.test` with `true`. This prevents WPD from trying to pattern match away `assume(type.test)` for public virtual calls when failing the pattern matching will result in miscompiles.

Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D128955

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[ThinLTO] Support aliased GlobalIFunc

Fixes https://github.com/llvm/llvm-project/issues/56290: when an ifunc is
aliased in LTO, clang will attempt to create an alias summary; however, as ifunc
is no

[ThinLTO] Support aliased GlobalIFunc

Fixes https://github.com/llvm/llvm-project/issues/56290: when an ifunc is
aliased in LTO, clang will attempt to create an alias summary; however, as ifunc
is not included in the module summary, doing so will lead to crash.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D129009

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[Analysis] Qualify auto variables in for loops (NFC)

[llvm] Don't use Optional::getValue (NFC)

[LTO] Initialize canAutoHide() using canBeOmittedFromSymbolTable()

Per discussion on
https://reviews.llvm.org/D59709#inline-1148734, this seems like the
right course of action. `canBeOmittedFromSymb

[LTO] Initialize canAutoHide() using canBeOmittedFromSymbolTable()

Per discussion on
https://reviews.llvm.org/D59709#inline-1148734, this seems like the
right course of action. `canBeOmittedFromSymbolTable()` subsumes and
generalizes the previous logic. In addition to handling `linkonce_odr`
`unnamed_addr` globals, we now also internalize `linkonce_odr` +
`local_unnamed_addr` constants.

Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D120173

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Cleanup includes: LLVMAnalysis

Number of lines output by preprocessor:
before: 1065940348
after: 1065307662

Discourse thread: https://discourse.llvm.org/t/include-what-you-use-include-cleanup
Diff

Cleanup includes: LLVMAnalysis

Number of lines output by preprocessor:
before: 1065940348
after: 1065307662

Discourse thread: https://discourse.llvm.org/t/include-what-you-use-include-cleanup
Differential Revision: https://reviews.llvm.org/D120659

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[LTO][WPD] Simplify mustBeUnreachableFunction and test after D115492

An well-formed IR function definition must have an entry basic block and
a well-formed IR basic block must have one terminator so

[LTO][WPD] Simplify mustBeUnreachableFunction and test after D115492

An well-formed IR function definition must have an entry basic block and
a well-formed IR basic block must have one terminator so the emptiness
check can be simplified.
Also simplify the test a bit.

Reviewed By: luna

Differential Revision: https://reviews.llvm.org/D115780

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[LTO] Ignore unreachable virtual functions in WPD in hybrid LTO.

Differential Revision: https://reviews.llvm.org/D115492

[IR][NFC] Rename getBaseObject to getAliaseeObject

To better reflect the meaning of the now-disambiguated {GlobalValue,
GlobalAlias}::getBaseObject after breaking off GlobalIFunc::getResolverFunctio

[IR][NFC] Rename getBaseObject to getAliaseeObject

To better reflect the meaning of the now-disambiguated {GlobalValue,
GlobalAlias}::getBaseObject after breaking off GlobalIFunc::getResolverFunction
(D109792), the function is renamed to getAliaseeObject.

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[ThinLTO] Add noRecurse and noUnwind thinlink function attribute propagation

Thinlink provides an opportunity to propagate function attributes across modules, enabling additional propagation opportu

[ThinLTO] Add noRecurse and noUnwind thinlink function attribute propagation

Thinlink provides an opportunity to propagate function attributes across modules, enabling additional propagation opportunities.

This change propagates (currently default off, turn on with `disable-thinlto-funcattrs=1`) noRecurse and noUnwind based off of function summaries of the prevailing functions in bottom-up call-graph order. Testing on clang self-build:
1. There's a 35-40% increase in noUnwind functions due to the additional propagation opportunities.
2. Throughput is measured at 10-15% increase in thinlink time which itself is 1.5% of E2E link time.

Implementation-wise this adds the following summary function attributes:
1. noUnwind: function is noUnwind
2. mayThrow: function contains a non-call instruction that `Instruction::mayThrow` returns true on (e.g. windows SEH instructions)
3. hasUnknownCall: function contains calls that don't make it into the summary call-graph thus should not be propagated from (e.g. indirect for now, could add no-opt functions as well)

Testing:
Clang self-build passes and 2nd stage build passes check-all
ninja check-all with newly added tests passing

Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D36850

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[CSSPGO] Tweakes to lower pseudo probe runtime overhead

A couple tweaks to

1. allow more thinlto importing by excluding probe intrinsics from IR size in module summary

2. Allow general default att

[CSSPGO] Tweakes to lower pseudo probe runtime overhead

A couple tweaks to

1. allow more thinlto importing by excluding probe intrinsics from IR size in module summary

2. Allow general default attributes (nofree nosync nounwind) for pseudo probe intrinsic. Without those attributes, pseudo probes will be basically treated as unknown calls which will in turn block their containing functions from annotated with those attributes.

Reviewed By: wenlei

Differential Revision: https://reviews.llvm.org/D109976

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[NFC] Rename AttributeList::hasFnAttribute() -> hasFnAttr()

This is more consistent with similar methods.

[ThinLTO] Disallow importing for functions with indir branch to block address

We don't allowing inlining for functions with blockaddress with uses other than strictly callbr. This is because if the

[ThinLTO] Disallow importing for functions with indir branch to block address

We don't allowing inlining for functions with blockaddress with uses other than strictly callbr. This is because if the blockaddress escapes the function via a global variable, inlining may lead to an invalid cross-function reference.

We check against such cases during inlining, however the check can fail for ThinLTO post-link because CFG simplification can incorrectly removes blocks based on wrong block reachability.

When we import a function with blockaddress taken in a global variable but without importing that variable, we won't go through value mapping to reflect the real address-taken-ness of the cloned blocks. For the imported clone, this leads to blocks reachable from indirect branch through global variable being incorrectly treated as unreachable and removed by SimplifyCFG.

Since inlining for such cases shouldn't be allowed in the first place, I'm marking them as ineligible for importing during pre-link to save the problem of missing address-taken-ness of imported clone as well as bad DCE and inlining.

Differential Revision: https://reviews.llvm.org/D106930

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[Support] Don't include VirtualFileSystem.h in CommandLine.h

CommandLine.h is indirectly included in ~50% of TUs when building
clang, and VirtualFileSystem.h is large.

(Already remarked by jhenders

[Support] Don't include VirtualFileSystem.h in CommandLine.h

CommandLine.h is indirectly included in ~50% of TUs when building
clang, and VirtualFileSystem.h is large.

(Already remarked by jhenderson on D70769.)

No behavior change.

Differential Revision: https://reviews.llvm.org/D100957

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Use AssumeInst in a few more places [nfc]

Follow up to a6d2a8d6f5. These were found by simply grepping for "::assume", and are the subset of that result which looked cleaner to me using the isa/dyn

Use AssumeInst in a few more places [nfc]

Follow up to a6d2a8d6f5. These were found by simply grepping for "::assume", and are the subset of that result which looked cleaner to me using the isa/dyn_cast patterns.

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[ModuleSummaryAnalysis] Avoid duplicate elements in Worklist. NFC

collectUsedGlobalVariables: migrate SmallPtrSetImpl overload to SmallVecImpl overload after D97128

And delete the SmallPtrSetImpl overload.

While here, decrease inline element counts from 8 to 4. S

collectUsedGlobalVariables: migrate SmallPtrSetImpl overload to SmallVecImpl overload after D97128

And delete the SmallPtrSetImpl overload.

While here, decrease inline element counts from 8 to 4. See D97128 for the choice.

Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D97257

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[Analysis] Use range-based for loops (NFC)

[ThinLTO] Add Visibility bits to GlobalValueSummary::GVFlags

Imported functions and variable get the visibility from the module supplying the
definition. However, non-imported definitions do not ge

[ThinLTO] Add Visibility bits to GlobalValueSummary::GVFlags

Imported functions and variable get the visibility from the module supplying the
definition. However, non-imported definitions do not get the visibility from
(ELF) the most constraining visibility among all modules (Mach-O) the visibility
of the prevailing definition.

This patch

* adds visibility bits to GlobalValueSummary::GVFlags
* computes the result visibility and propagates it to all definitions

Protected/hidden can imply dso_local which can enable some optimizations (this
is stronger than GVFlags::DSOLocal because the implied dso_local can be
leveraged for ELF -shared while default visibility dso_local has to be cleared
for ELF -shared).

Note: we don't have summaries for declarations, so for ELF if a declaration has
the most constraining visibility, the result visibility may not be that one.

Differential Revision: https://reviews.llvm.org/D92900

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[llvm] Use the default value of drop_begin (NFC)

[llvm] Use llvm::drop_begin (NFC)

[StackSafety] Use ValueInfo in ParamAccess::Call

This avoid GUID lookup in Index.findSummaryInModule.
Follow up for D81242.

Reviewed By: tejohnson

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

[StackSafety] Use ValueInfo in ParamAccess::Call

This avoid GUID lookup in Index.findSummaryInModule.
Follow up for D81242.

Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D85269

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[StackSafety] Pass summary into codegen

Summary:
The patch wraps ThinLTO index into immutable
pass which can be used by StackSafety analysis.

Reviewers: eugenis, pcc

Reviewed By: eugenis

Subscrib

[StackSafety] Pass summary into codegen

Summary:
The patch wraps ThinLTO index into immutable
pass which can be used by StackSafety analysis.

Reviewers: eugenis, pcc

Reviewed By: eugenis

Subscribers: hiraditya, steven_wu, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80985

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[StackSafety] Add info into function summary

Summary:
This patch adds optional field into function summary,
implements asm and bitcode serialization. YAML
serialization is omitted and can be added l

[StackSafety] Add info into function summary

Summary:
This patch adds optional field into function summary,
implements asm and bitcode serialization. YAML
serialization is omitted and can be added later if
needed.

This patch includes this information into summary only
if module contains at least one sanitize_memtag function.
In a near future MTE is the user of the analysis.
Later if needed we can provede more direct control
on when information is included into summary.

Reviewers: eugenis

Subscribers: hiraditya, steven_wu, dexonsmith, arphaman, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80908

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[ThinLTO] Compute the basic block count across modules.

Summary:
Count the per-module number of basic blocks when the module summary is computed
and sum them up during Thin LTO indexing.

This is us

[ThinLTO] Compute the basic block count across modules.

Summary:
Count the per-module number of basic blocks when the module summary is computed
and sum them up during Thin LTO indexing.

This is used to estimate the working set size under the partial sample PGO.

This is split off of D79831.

Reviewers: davidxl, espindola

Subscribers: emaste, inglorion, hiraditya, MaskRay, steven_wu, dexonsmith, arphaman, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80403

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