18 Commits

Author SHA1 Message Date
Hari Limaye
94473f4db6
[IRBuilder] Generate nuw GEPs for struct member accesses (#99538)
Generate nuw GEPs for struct member accesses, as inbounds + non-negative
implies nuw.

Regression tests are updated using update scripts where possible, and by
find + replace where not.
2024-08-09 13:25:04 +01:00
Nikita Popov
cc2dc0916a Reapply [ConstantFold] Drop gep of gep fold entirely (#95126)
Reapplying without changes. The flang+openmp buildbot failure
should be addressed by https://github.com/llvm/llvm-project/pull/94541.

-----

This is a followup to https://github.com/llvm/llvm-project/pull/93823
and drops the DataLayout-unaware GEP of GEP fold entirely. All cases are
now left to the DataLayout-aware constant folder, which will fold
everything to a single i8 GEP.

We didn't have any test coverage for this fold in LLVM, but some Clang
tests change.
2024-06-13 17:03:35 +02:00
Nikita Popov
cece0a105b Revert "[ConstantFold] Drop gep of gep fold entirely (#95126)"
This reverts commit 3b3b839c66dc49674fd6646650525a2173030690.

This broke the flang+openmp+offload buildbot, as reported in
https://github.com/llvm/llvm-project/pull/95126#issuecomment-2162424019.
2024-06-12 11:52:12 +02:00
Nikita Popov
3b3b839c66
[ConstantFold] Drop gep of gep fold entirely (#95126)
This is a followup to https://github.com/llvm/llvm-project/pull/93823
and drops the DataLayout-unaware GEP of GEP fold entirely. All cases are
now left to the DataLayout-aware constant folder, which will fold
everything to a single i8 GEP.

We didn't have any test coverage for this fold in LLVM, but some Clang
tests change.
2024-06-12 09:50:14 +02:00
Nikita Popov
51e459a561 Revert "[ConstantFold] Remove non-trivial gep-of-gep fold (#93823)"
This reverts commit e1cc9e4eaddcc295b4e775512e33b947b1514c17.

This causes some non-trivial text size increases in unoptimized
builds for Bullet. Revert while I investigate.
2024-05-31 10:37:32 +02:00
Nikita Popov
e1cc9e4ead
[ConstantFold] Remove non-trivial gep-of-gep fold (#93823)
This fold is subtly incorrect, because DL-unaware constant folding does
not know the correct index type to use, and just performs the addition
in the type that happens to already be there. This is incorrect, since
sext(X)+sext(Y) is generally not the same as sext(X+Y). See the
`@constexpr_gep_of_gep_with_narrow_type()` for a miscompile with the
current implementation.

One could try to restrict the fold to cases where no overflow occurs,
but I'm not bothering with that here, because the DL-aware constant
folding will take care of this anyway. I've only kept the
straightforward zero-index case, where we just concatenate two GEPs.
2024-05-31 09:25:38 +02:00
Nikita Popov
d10b76552f
[ConstantFold] Remove notional over-indexing fold (#93697)
The data-layout independent constant folding currently has some rather
gnarly code for canonicalizing GEP indices to reduce "notional
overindexing", and then infers inbounds based on that canonicalization.

Now that we canonicalize to i8 GEPs, this canonicalization is
essentially useless, as we'll discard it as soon as the GEP hits the
data-layout aware constant folder anyway. As such, I'd like to remove
this code entirely.

This shouldn't have any impact on optimization capabilities.
2024-05-30 08:36:44 +02:00
Nikita Popov
d3d5cdbfa8 [Clang] Convert some tests to opaque pointers (NFC) 2023-06-08 10:01:28 +02:00
Nikita Popov
532dc62b90 [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
2022-04-07 12:09:47 +02:00
Fangrui Song
fd739804e0 [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 `{{.*}} `.
2020-12-31 00:27:11 -08:00
David Blaikie
bdf40a62a7 Test case updates for explicit type parameter to the gep operator
llvm-svn: 232187
2015-03-13 18:21:46 +00:00
David Majnemer
c9a9c7a673 CodeGen: static constexpr data members should have a linkonce_odr init
Classes can be defined in multiple translation units.  This means that
the static constexpr data members should have identical initializers in
all translation units.  Implement this by giving the reference temporary
linkonce_odr linkage.

llvm-svn: 229900
2015-02-19 19:25:17 +00:00
David Majnemer
3b3bdb5169 AST: Update reference temporary mangling
Summary:
Update our mangling to match the discussion on cxx-abi-dev.

This involves using a seq-id instead of an optional number.

Reviewers: rsmith

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D3631

llvm-svn: 208140
2014-05-06 22:49:16 +00:00
David Majnemer
daff37013c AST: Mangle reference temporaries reliably
Summary:
Previously, we would generate a single name for all reference
temporaries and allow LLVM to rename them for us.  Instead, number the
reference temporaries as we build them in Sema.

Reviewers: rsmith

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D3554

llvm-svn: 207776
2014-05-01 17:50:17 +00:00
Nico Rieck
e6a1582595 Fix broken CHECK lines
llvm-svn: 201477
2014-02-16 07:29:41 +00:00
Richard Smith
a509f2fdfa Emit initializers for static-storage-duration temporaries as constants where
possible.

llvm-svn: 183967
2013-06-14 03:07:01 +00:00
Richard Smith
cc1b96d356 PR12086, PR15117
Introduce CXXStdInitializerListExpr node, representing the implicit
construction of a std::initializer_list<T> object from its underlying array.
The AST representation of such an expression goes from an InitListExpr with a
flag set, to a CXXStdInitializerListExpr containing a MaterializeTemporaryExpr
containing an InitListExpr (possibly wrapped in a CXXBindTemporaryExpr).

This more detailed representation has several advantages, the most important of
which is that the new MaterializeTemporaryExpr allows us to directly model
lifetime extension of the underlying temporary array. Using that, this patch
*drastically* simplifies the IR generation of this construct, provides IR
generation support for nested global initializer_list objects, fixes several
bugs where the destructors for the underlying array would accidentally not get
invoked, and provides constant expression evaluation support for
std::initializer_list objects.

llvm-svn: 183872
2013-06-12 22:31:48 +00:00
Sebastian Redl
a235e2d8ad Hack in a loud error for PR12086. Better than a silent miscompile.
llvm-svn: 151586
2012-02-27 23:20:01 +00:00