[IR] Change representation of getelementptr inrange (#84341)

As part of the migration to ptradd
(https://discourse.llvm.org/t/rfc-replacing-getelementptr-with-ptradd/68699),
we need to change the

[IR] Change representation of getelementptr inrange (#84341)

As part of the migration to ptradd
(https://discourse.llvm.org/t/rfc-replacing-getelementptr-with-ptradd/68699),
we need to change the representation of the `inrange` attribute, which
is used for vtable splitting.

Currently, inrange is specified as follows:

```
getelementptr inbounds ({ [4 x ptr], [4 x ptr] }, ptr @vt, i64 0, inrange i32 1, i64 2)
```

The `inrange` is placed on a GEP index, and all accesses must be "in
range" of that index. The new representation is as follows:

```
getelementptr inbounds inrange(-16, 16) ({ [4 x ptr], [4 x ptr] }, ptr @vt, i64 0, i32 1, i64 2)
```

This specifies which offsets are "in range" of the GEP result. The new
representation will continue working when canonicalizing to ptradd
representation:

```
getelementptr inbounds inrange(-16, 16) (i8, ptr @vt, i64 48)
```

The inrange offsets are relative to the return value of the GEP. An
alternative design could make them relative to the source pointer
instead. The result-relative format was chosen on the off-chance that we
want to extend support to non-constant GEPs in the future, in which case
this variant is more expressive.

This implementation "upgrades" the old inrange representation in bitcode
by simply dropping it. This is a very niche feature, and I don't think
trying to upgrade it is worthwhile. Let me know if you disagree.

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[CGExprConstant] stop calling into ConstExprEmitter for Reference type destinations (#70366)

Fixes a bug introduced by
commit b54294e2c959 ("[clang][ConstantEmitter] have
tryEmitPrivate[ForVarInit]

[CGExprConstant] stop calling into ConstExprEmitter for Reference type destinations (#70366)

Fixes a bug introduced by
commit b54294e2c959 ("[clang][ConstantEmitter] have
tryEmitPrivate[ForVarInit] try ConstExprEmitter fast-path first")

In the added test case, the QualType is a LValueReferenceType.

LValueReferenceType 0x558412998d90 'const char (&)[41]'
`-ParenType 0x558412998d30 'const char[41]' sugar
`-ConstantArrayType 0x558412998cf0 'const char[41]' 41
`-QualType 0x55841294c271 'const char' const
`-BuiltinType 0x55841294c270 'char'

Fixes: #69979

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[clang][ConstantEmitter] have tryEmitPrivate[ForVarInit] try ConstExprEmitter fast-path first

As suggested by @efriedma in:
https://reviews.llvm.org/D76096#4370369

This should speed up evaluating w

[clang][ConstantEmitter] have tryEmitPrivate[ForVarInit] try ConstExprEmitter fast-path first

As suggested by @efriedma in:
https://reviews.llvm.org/D76096#4370369

This should speed up evaluating whether an expression is constant or
not, but due to the complexity of these two different implementations,
we may start getting different answers for edge cases for which we do
not yet have test cases in-tree (or perhaps even performance regressions
for some cases). As such, contributors have carte blanche to revert if
necessary.

For additional historical context about ExprConstant vs CGExprConstant,
here's snippets from a private conversation on discord:

ndesaulniers:
why do we have clang/lib/AST/ExprConstant.cpp and
clang/lib/CodeGen/CGExprConstant.cpp? Does clang constant fold during
ast walking/creation AND during LLVM codegen?
efriedma:
originally, clang needed to handle two things: integer constant
expressions (the "5" in "int x[5];"), and constant global initializers
(the "5" in "int x = 5;"). pre-C++11, the two could be handled mostly
separately; so we had the code for integer constants in AST/, and the
code for globals in CodeGen/. C++11 constexpr sort of destroyed that
separation, though. so now we do both kinds of constant evaluation on
the AST, then CGExprConstant translates the result of that evaluation
to LLVM IR. but we kept around some bits of the old cgexprconstant to
avoid performance/memory usage regressions on large arrays.

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D151587

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[clang] Convert a few tests to opaque pointers

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D150887

Emit const globals with constexpr destructor as constant LLVM values

This follows 2b4fa53 which made Clang not emit destructor calls for such
objects. However, they would still not get emitted as co

Emit const globals with constexpr destructor as constant LLVM values

This follows 2b4fa53 which made Clang not emit destructor calls for such
objects. However, they would still not get emitted as constants since
CodeGenModule::isTypeConstant() returns false if the destructor is
constexpr. This change adds a param to make isTypeConstant() ignore the
dtor, allowing the caller to check it instead.

Fixes Issue #61212

Differential revision: https://reviews.llvm.org/D145369

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[OpaquePtrs][Clang] Add -no-opaque-pointers to tests (NFC)

This adds -no-opaque-pointers to clang tests whose output will
change when opaque pointers are enabled by default. This is
intended to be p

[OpaquePtrs][Clang] Add -no-opaque-pointers to tests (NFC)

This adds -no-opaque-pointers to clang tests whose output will
change when opaque pointers are enabled by default. This is
intended to be part of the migration approach described in
https://discourse.llvm.org/t/enabling-opaque-pointers-by-default/61322/9.

The patch has been produced by replacing %clang_cc1 with
%clang_cc1 -no-opaque-pointers for tests that fail with opaque
pointers enabled. Worth noting that this doesn't cover all tests,
there's a remaining ~40 tests not using %clang_cc1 that will need
a followup change.

Differential Revision: https://reviews.llvm.org/D123115

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[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default

Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I

[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default

Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I modified clang by renaming `enable_noundef_analysis` flag to `disable-noundef-analysis` and turning it off by default.

Test updates are made as a separate patch: D108453

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D105169

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Revert "[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default"

This reverts commit aacfbb953eb705af2ecfeb95a6262818fa85dd92.

Revert "Fix lit test failu

Revert "[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default"

This reverts commit aacfbb953eb705af2ecfeb95a6262818fa85dd92.

Revert "Fix lit test failures in CodeGenCoroutines"

This reverts commit 63fff0f5bffe20fa2c84a45a41161afa0043cb34.

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[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default

Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I

[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default

Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I modified clang by renaming `enable_noundef_analysis` flag to `disable-noundef-analysis` and turning it off by default.

Test updates are made as a separate patch: D108453

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D105169

[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default (2)

This patch updates test files after D105169.
Autogenerated test codes are changed by `utils/update_cc_test_checks.py,` and non-autogenerated test codes are changed as follows:

(1) I wrote a python script that (partially) updates the tests using regex: {F18594904} The script is not perfect, but I believe it gives hints about which patterns are updated to have `noundef` attached.

(2) The remaining tests are updated manually.

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D108453

Resolve lit failures in clang after 8ca4b3e's land

Fix lit test failures in clang-ppc* and clang-x64-windows-msvc

Fix missing failures in clang-ppc64be* and retry fixing clang-x64-windows-msvc

Fix internal_clone(aarch64) inline assembly

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Revert "[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default"

This reverts commit 7584ef766a7219b6ee5a400637206d26e0fa98ac.

[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default

Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I

[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default

Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I modified clang by renaming `enable_noundef_analysis` flag to `disable-noundef-analysis` and turning it off by default.

Test updates are made as a separate patch: D108453

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D105169

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Revert D105169 due to the two-stage failure in ASAN

This reverts the following commits:
37ca7a795b277c20c02a218bf44052278c03344b
9aa6c72b92b6c89cc6d23b693257df9af7de2d15
705387c5074bcca36d626882462e

Revert D105169 due to the two-stage failure in ASAN

This reverts the following commits:
37ca7a795b277c20c02a218bf44052278c03344b
9aa6c72b92b6c89cc6d23b693257df9af7de2d15
705387c5074bcca36d626882462ebbc2bcc3bed4
8ca4b3ef19fe82d7ad6a6e1515317dcc01b41515
80dba72a669b5416e97a42fd2c2a7bc5a6d3f44a

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[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default (2)

This patch updates test files after D105169.
Autogenerated test codes are changed by `utils/up

[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default (2)

This patch updates test files after D105169.
Autogenerated test codes are changed by `utils/update_cc_test_checks.py,` and non-autogenerated test codes are changed as follows:

(1) I wrote a python script that (partially) updates the tests using regex: {F18594904} The script is not perfect, but I believe it gives hints about which patterns are updated to have `noundef` attached.

(2) The remaining tests are updated manually.

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D108453

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[test] Add {{.*}} to make ELF tests immune to dso_local/dso_preemptable/(none) differences

For a default visibility external linkage definition, dso_local is set for ELF
-fno-pic/-fpie and COFF and

[test] Add {{.*}} to make ELF tests immune to dso_local/dso_preemptable/(none) differences

For a default visibility external linkage definition, dso_local is set for ELF
-fno-pic/-fpie and COFF and Mach-O. Since default clang -cc1 for ELF is similar
to -fpic ("PIC Level" is not set), this nuance causes unneeded binary format differences.

To make emitted IR similar, ELF -cc1 -fpic will default to -fno-semantic-interposition,
which sets dso_local for default visibility external linkage definitions.

To make this flip smooth and enable future (dso_local as definition default),
this patch replaces (function) `define ` with `define{{.*}} `,
(variable/constant/alias) `= ` with `={{.*}} `, or inserts appropriate `{{.*}} `.

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[CodeGen] Apply 'nonnull' and 'dereferenceable(N)' to 'this' pointer
arguments.

* Adds 'nonnull' and 'dereferenceable(N)' to 'this' pointer arguments
* Gates 'nonnull' on -f(no-)delete-null-pointer-

[CodeGen] Apply 'nonnull' and 'dereferenceable(N)' to 'this' pointer
arguments.

* Adds 'nonnull' and 'dereferenceable(N)' to 'this' pointer arguments
* Gates 'nonnull' on -f(no-)delete-null-pointer-checks
* Introduces this-nonnull.cpp and microsoft-abi-this-nullable.cpp tests to
explicitly test the behavior of this change
* Refactors hundreds of over-constrained clang tests to permit these
attributes, where needed
* Updates Clang12 patch notes mentioning this change

Reviewed-by: rsmith, jdoerfert

Differential Revision: https://reviews.llvm.org/D17993

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PR47954 / DR2126: permit temporary objects that are lifetime-extended by
variables that are usable in constant expressions to themselves be
usable in constant expressions.

[CGCall] Annotate references with "align" attribute.

If we're going to assume references are dereferenceable, we should also
assume they're aligned: otherwise, we can't actually dereference them.

S

[CGCall] Annotate references with "align" attribute.

If we're going to assume references are dereferenceable, we should also
assume they're aligned: otherwise, we can't actually dereference them.

See also D80072.

Differential Revision: https://reviews.llvm.org/D80166

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Revert "[CodeGenModule] Assume dso_local for -fpic -fno-semantic-interposition"

This reverts commit 789a46f2d742e11edaade28cb59a0f4d2a1d770e.

Accidentally committed.

[CodeGenModule] Assume dso_local for -fpic -fno-semantic-interposition

Summary:
Clang -fpic defaults to -fno-semantic-interposition (GCC -fpic defaults
to -fsemantic-interposition).
Users need to sp

[CodeGenModule] Assume dso_local for -fpic -fno-semantic-interposition

Summary:
Clang -fpic defaults to -fno-semantic-interposition (GCC -fpic defaults
to -fsemantic-interposition).
Users need to specify -fsemantic-interposition to get semantic
interposition behavior.

Semantic interposition is currently a best-effort feature. There may
still be some cases where it is not handled well.

Reviewers: peter.smith, rnk, serge-sans-paille, sfertile, jfb, jdoerfert

Subscribers: dschuff, jyknight, dylanmckay, nemanjai, jvesely, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, arphaman, PkmX, jocewei, jsji, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D73865

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[opaque pointer types] Cleanup CGBuilder's Create*GEP.

Some of these functions take some extraneous arguments, e.g. EltSize,
Offset, which are computable from the Type and DataLayout.

Add some asse

[opaque pointer types] Cleanup CGBuilder's Create*GEP.

Some of these functions take some extraneous arguments, e.g. EltSize,
Offset, which are computable from the Type and DataLayout.

Add some asserts to ensure that the computed values are consistent
with the passed-in values, in preparation for eliminating the
extraneous arguments. This also asserts that the Type is an Array for
the calls named "Array" and a Struct for the calls named "Struct".

Then, correct a couple of errors:

1. Using CreateStructGEP on an array type. (this causes the majority
of the test differences, as struct GEPs are created with i32
indices, while array GEPs are created with i64 indices)

2. Passing the wrong Offset to CreateStructGEP in TargetInfo.cpp on
x86-64 NACL (which uses 32-bit pointers).

Differential Revision: https://reviews.llvm.org/D57766

llvm-svn: 353529

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CGDecl::emitStoresForConstant fix synthesized constant's name

Summary: The name of the synthesized constants for constant initialization was using mangling for statics, which isn't generally correct

CGDecl::emitStoresForConstant fix synthesized constant's name

Summary: The name of the synthesized constants for constant initialization was using mangling for statics, which isn't generally correct and (in a yet-uncommitted patch) causes the mangler to assert out because the static ends up trying to mangle function parameters and this makes no sense. Instead, mangle to `"__const." + FunctionName + "." + DeclName`.

Reviewers: rjmccall

Subscribers: dexonsmith, cfe-commits

Differential Revision: https://reviews.llvm.org/D54055

llvm-svn: 346915

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Disable -fmerge-all-constants as default.

Summary:
"-fmerge-all-constants" is a non-conforming optimization and should not
be the default. It is also causing miscompiles when building Linux
Kernel (

Disable -fmerge-all-constants as default.

Summary:
"-fmerge-all-constants" is a non-conforming optimization and should not
be the default. It is also causing miscompiles when building Linux
Kernel (https://lkml.org/lkml/2018/3/20/872).

Fixes PR18538.

Reviewers: rjmccall, rsmith, chandlerc

Reviewed By: rsmith, chandlerc

Subscribers: srhines, cfe-commits

Differential Revision: https://reviews.llvm.org/D45289

llvm-svn: 329300

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CodeGen: Start using inrange annotations on vtable getelementptr.

This annotation allows the optimizer to split vtable groups, as permitted by
a change to the Itanium ABI [1] that prevents compilers

CodeGen: Start using inrange annotations on vtable getelementptr.

This annotation allows the optimizer to split vtable groups, as permitted by
a change to the Itanium ABI [1] that prevents compilers from adjusting virtual
table pointers between virtual tables.

[1] https://github.com/MentorEmbedded/cxx-abi/pull/7

Differential Revision: https://reviews.llvm.org/D24431

llvm-svn: 289585

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CodeGen: New vtable group representation: struct of vtable arrays.

In a future change, this representation will allow us to use the new inrange
annotation on getelementptr to allow the optimizer to

CodeGen: New vtable group representation: struct of vtable arrays.

In a future change, this representation will allow us to use the new inrange
annotation on getelementptr to allow the optimizer to split vtable groups.

Differential Revision: https://reviews.llvm.org/D22296

llvm-svn: 289584

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CodeGen: Use 32-bit gep offsets to address vtable address points.

The relative vtable ABI will use a struct rather than an array as the type
of a vtable. LLVM only allows 32-bit integers as struct i

CodeGen: Use 32-bit gep offsets to address vtable address points.

The relative vtable ABI will use a struct rather than an array as the type
of a vtable. LLVM only allows 32-bit integers as struct indices, so we need
to use 32-bit integers to get addresses of address points. In order to keep
the code simple, we might as well do that unconditionally.

It's probably a reasonable implementation limit to support no more than 2
billion virtual functions per class.

This change causes quite a bit of churn in the test suite, so I'm making
it separately.

Differential Revision: http://reviews.llvm.org/D18113

llvm-svn: 263469

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