[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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[LegacyPM] Remove WholeProgramDevirt

Unused after LTO removal from legacy optimization passline.

[NFC] Switch a few uses of undef to poison as placeholders for unreachble code

Remove unneeded cl::ZeroOrMore for cl::opt/cl::list options

Remove unneeded cl::ZeroOrMore for cl::list options

Remove unneeded cl::ZeroOrMore for cl::opt options

Similar to 557efc9a8b68628c2c944678c6471dac30ed9e8e.
This commit handles options where cl::ZeroOrMore is more than one line below
cl::opt.

[llvm] Remove unneeded cl::ZeroOrMore for cl::opt options. NFC

Some cl::ZeroOrMore were added to avoid the `may only occur zero or one times!`
error. More were added due to cargo cult. Since the err

[llvm] Remove unneeded cl::ZeroOrMore for cl::opt options. NFC

Some cl::ZeroOrMore were added to avoid the `may only occur zero or one times!`
error. More were added due to cargo cult. Since the error has been removed,
cl::ZeroOrMore is unneeded.

Also remove cl::init(false) while touching the lines.

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[NFC] Rename Instrinsic to Intrinsic

[WPD] Add statistics

Add statistics to count overall devirtualized targets as well as the
various types of devirtualizations applied at callsites.

Differential Revision: https://reviews.llvm.org/D1

[WPD] Add statistics

Add statistics to count overall devirtualized targets as well as the
various types of devirtualizations applied at callsites.

Differential Revision: https://reviews.llvm.org/D123152

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[FunctionAttrs] Replace MemoryAccessKind with FMRB.

Update FunctionAttrs to use FunctionModRefBehavior instead
MemoryAccessKind.

This allows for adding support for inferring argmemonly and others,

[FunctionAttrs] Replace MemoryAccessKind with FMRB.

Update FunctionAttrs to use FunctionModRefBehavior instead
MemoryAccessKind.

This allows for adding support for inferring argmemonly and others,
see D121415.

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D121460

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[WPD] Extend checking mode to support fallback to indirect call

Extend -wholeprogramdevirt-check to support both the existing
trapping mode on an incorrect devirtualization, as well as a new
mode to

[WPD] Extend checking mode to support fallback to indirect call

Extend -wholeprogramdevirt-check to support both the existing
trapping mode on an incorrect devirtualization, as well as a new
mode to fallback to an indirect call on a mismatch. The new mode is

The new mode is useful in cases where we want to enable
devirtualization but cannot fully guarantee whole program visibility
(e.g in the case where LTO has been disabled for a small set of objects
that could potentially override virtual methods without having a symbol
reference to anything in the base class including the vtable).

Remove !prof and !callees metadata (which are used by indirect call
promotion) from both the new direct call and the fallback indirect call
(so that we don't perform another round of promotion on the latter).
Also remove it from the direct call in the non-fallback cases, which
was an oversight, although it didn't seem to cause any issues. Add tests
for the metadata removal covering the various cases.

Differential Revision: https://reviews.llvm.org/D121419

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[ThinLTO][WPD] LICM set lookup (NFC)

Minor efficiency fix. There is no reason to perform the same set lookup
repeatedly in the inner loop as it is invariant there.

Differential Revision: https://re

[ThinLTO][WPD] LICM set lookup (NFC)

Minor efficiency fix. There is no reason to perform the same set lookup
repeatedly in the inner loop as it is invariant there.

Differential Revision: https://reviews.llvm.org/D119474

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[BitcodeWriter] Fix cases of some functions

`WriteIndexToFile` is used by external projects so I do not touch it.

[LTO][WPD] Ignore unreachable function by analyzing IR.

In regular LTO, analyze IR and discard unreachable functions when finding virtual call targets.

Differential Revision: https://reviews.llvm.o

[LTO][WPD] Ignore unreachable function by analyzing IR.

In regular LTO, analyze IR and discard unreachable functions when finding virtual call targets.

Differential Revision: https://reviews.llvm.org/D116056

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[ThinLTO] Ignore unreachable virtual functions in WPD in thin LTO.

Differential Revision: https://reviews.llvm.org/D115648

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

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

[NFC] Replace some deprecated getAlignment() calls with getAlign()

Reviewed By: gchatelet

Differential Revision: https://reviews.llvm.org/D115370

[Transforms] Use make_early_inc_range (NFC)

[NFC] Replace Function handling of attributes with less confusing calls

To avoid magic constants and confusing indexes.

[NFC] Rename AttributeList::getParam/Ret/FnAttributes() -> get*Attributes()

This is more consistent with similar methods.

[WPD] Don't optimize calls more than once

WPD currently assumes that there is a one to one correspondence between
type test assume sequences and virtual calls. However, with
-fstrict-vtable-pointers

[WPD] Don't optimize calls more than once

WPD currently assumes that there is a one to one correspondence between
type test assume sequences and virtual calls. However, with
-fstrict-vtable-pointers this may not be true. This ends up causing
crashes when we try to optimize a virtual call more than once (
applyUniformRetValOpt()/applyUniqueRetValOpt()/applyVirtualConstProp()/applySingleImplDevirt()).

applySingleImplDevirt() actually didn't previous crash because it would
replace the devirtualized call with the same direct call. Adding an
assert that the call is indirect causes the corresponding test to crash
with the rest of the patch.

This makes Chrome successfully build with -fstrict-vtable-pointers + WPD.

Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D104798

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Internalize some cl::opt global variables or move them under namespace llvm

[SystemZ][z/OS][Windows] Add new OF_TextWithCRLF flag and use this flag instead of OF_Text

Problem:
On SystemZ we need to open text files in text mode. On Windows, files opened in text mode adds a C

[SystemZ][z/OS][Windows] Add new OF_TextWithCRLF flag and use this flag instead of OF_Text

Problem:
On SystemZ we need to open text files in text mode. On Windows, files opened in text mode adds a CRLF '\r\n' which may not be desirable.

Solution:
This patch adds two new flags

- OF_CRLF which indicates that CRLF translation is used.
- OF_TextWithCRLF = OF_Text | OF_CRLF indicates that the file is text and uses CRLF translation.

Developers should now use either the OF_Text or OF_TextWithCRLF for text files and OF_None for binary files. If the developer doesn't want carriage returns on Windows, they should use OF_Text, if they do want carriage returns on Windows, they should use OF_TextWithCRLF.

So this is the behaviour per platform with my patch:

z/OS:
OF_None: open in binary mode
OF_Text : open in text mode
OF_TextWithCRLF: open in text mode

Windows:
OF_None: open file with no carriage return
OF_Text: open file with no carriage return
OF_TextWithCRLF: open file with carriage return

The Major change is in llvm/lib/Support/Windows/Path.inc to only set text mode if the OF_CRLF is set.
```
if (Flags & OF_CRLF)
CrtOpenFlags |= _O_TEXT;
```

These following files are the ones that still use OF_Text which I left unchanged. I modified all these except raw_ostream.cpp in recent patches so I know these were previously in Binary mode on Windows.
./llvm/lib/Support/raw_ostream.cpp
./llvm/lib/TableGen/Main.cpp
./llvm/tools/dsymutil/DwarfLinkerForBinary.cpp
./llvm/unittests/Support/Path.cpp
./clang/lib/StaticAnalyzer/Core/HTMLDiagnostics.cpp
./clang/lib/Frontend/CompilerInstance.cpp
./clang/lib/Driver/Driver.cpp
./clang/lib/Driver/ToolChains/Clang.cpp

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D99426

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Don't use $ as suffix for symbol names in ThinLTOBitcodeWriter and other places

Using $ breaks demangling of the symbols. For example,

$ c++filt _Z3foov\$123
_Z3foov$123

This causes problems for d

Don't use $ as suffix for symbol names in ThinLTOBitcodeWriter and other places

Using $ breaks demangling of the symbols. For example,

$ c++filt _Z3foov\$123
_Z3foov$123

This causes problems for developers who would like to see nice stack traces
etc., but also for automatic crash tracking systems which try to organize
crashes based on the stack traces.

Instead, use the period as suffix separator, since Itanium demanglers normally
ignore such suffixes:

$ c++filt _Z3foov.123
foo() [clone .123]

This is already done in some places; try to do it everywhere.

Differential revision: https://reviews.llvm.org/D97484

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[WPD] Fix handling of pure virtual base class

The fix in 3c4c205060c9398da705eb71b63ddd8a04999de9 caused an assert in
the case of a pure virtual base class. In that case, the vTableFuncs
list on the

[WPD] Fix handling of pure virtual base class

The fix in 3c4c205060c9398da705eb71b63ddd8a04999de9 caused an assert in
the case of a pure virtual base class. In that case, the vTableFuncs
list on the summary will be empty, so we were hitting the new assert
that the linkage type was not available_externally.

In the case of pure virtual, we do not want to assert, and additionally
need to set VS so that we don't treat it conservatively and quit the
analysis of the type id early.

This exposed a pre-existing issue where we were not updating the vcall
visibility on pure virtual functions when whole program visibility was
specified. We were skipping updating the visibility on any global vars
that didn't have any vTableFuncs, which meant all pure virtual were not
updated, and the later analysis would block any devirtualization of
calls that had a type id used on those pure virtual vtables (see the
handling in the other code modified in this patch). Simply remove that
check. It will mean that we may update the vcall visibility on global
vars that aren't vtables, but that setting is ignored for any global
vars that didn't have type metadata anyway.

Added a new test case that asserted without removing the assert, and
that requires the other fixes in this patch (updateVCallVisibilityInIndex
and not skipping all vtables without virtual funcs) to get a successful
devirtualization with index-only WPD. I added cases to test hybrid and
regular LTO for completeness, although those already worked without the
fixes here.

With this final fix, a clang multistage bootstrap with WPD builds and
runs all tests successfully.

Differential Revision: https://reviews.llvm.org/D97126

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