Commit Graph

18 Commits

Author SHA1 Message Date
Fangrui Song 6b3351792c [test] Add {{.*}} to make tests immune to dso_local/dso_preemptable/(none) differences
For a definition (of most linkage types), dso_local is set for ELF -fno-pic/-fpie
and COFF, but not for Mach-O.  This nuance causes unneeded binary format differences.

This patch replaces (function) `define ` with `define{{.*}} `,
(variable/constant/alias) `= ` with `={{.*}} `, or inserts appropriate `{{.*}} `
if there is an explicit linkage.

* Clang will set dso_local for Mach-O, which is currently implied by TargetMachine.cpp. This will make COFF/Mach-O and executable ELF similar.
* Eventually I hope we can make dso_local the textual LLVM IR default (write explicit "dso_preemptable" when applicable) and -fpic ELF will be similar to everything else. This patch helps move toward that goal.
2020-12-30 20:52:01 -08:00
CJ Johnson 69cd776e1e [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
2020-11-16 17:39:17 -08:00
Sean Fertile d900dd0c23 Revert "[CodeGenCXX] Treat 'this' as noalias in constructors"
This reverts commit https://reviews.llvm.org/rL344150 which causes
MachineOutliner related failures on the ppc64le multistage buildbot.

llvm-svn: 344526
2018-10-15 15:43:00 +00:00
Anton Bikineev cc7e74753a [CodeGenCXX] Treat 'this' as noalias in constructors
This is currently a clang extension and a resolution
of the defect report in the C++ Standard.

Differential Revision: https://reviews.llvm.org/D46441

llvm-svn: 344150
2018-10-10 16:14:51 +00:00
Piotr Padlewski 0705829e40 [CodeGenCXX] Emit strip.invariant.group with -fstrict-vtable-pointers
Summary:
Emmiting new intrinsic that strips invariant.groups to make
devirtulization sound, as described in RFC: Devirtualization v2.

Reviewers: rjmccall, rsmith, amharc, kuhar

Subscribers: llvm-commits, cfe-commits

Differential Revision: https://reviews.llvm.org/D47299

Co-authored-by: Krzysztof Pszeniczny <krzysztof.pszeniczny@gmail.com>
llvm-svn: 336137
2018-07-02 19:21:36 +00:00
Piotr Padlewski 5dde809404 Rename invariant.group.barrier to launder.invariant.group
Summary:
This is one of the initial commit of "RFC: Devirtualization v2" proposal:
https://docs.google.com/document/d/16GVtCpzK8sIHNc2qZz6RN8amICNBtvjWUod2SujZVEo/edit?usp=sharing

Reviewers: rsmith, amharc, kuhar, sanjoy

Subscribers: arsenm, nhaehnle, javed.absar, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D45111

llvm-svn: 331448
2018-05-03 11:03:01 +00:00
Yaxun Liu abf5b27f7a Update tests for llvm.invariant.group.barrier becoming mangled
Differential Revision: https://reviews.llvm.org/D40062

llvm-svn: 318414
2017-11-16 16:33:04 +00:00
Piotr Padlewski 4446e508ed Fixed broken test (strict-vtable-pointers)
llvm-svn: 304455
2017-06-01 19:08:05 +00:00
Piotr Padlewski c1d26062f7 Emit invariant.group.barrier when using union field
Summary:
We need to emit barrier if the union field
is CXXRecordDecl because it might have vptrs. The testcode
was wrongly devirtualized. It also proves that having different
groups for different dynamic types is not sufficient.

Reviewers: rjmccall, rsmith, mehdi_amini

Subscribers: amharc, cfe-commits

Differential Revision: https://reviews.llvm.org/D31830

llvm-svn: 304448
2017-06-01 18:39:34 +00:00
Matthias Braun a451953224 CodeGenModule: Always output wchar_size, check LLVM assumptions.
Re-commit r303463 now that LLVM is fixed and adjust some lit tests.

llvm::TargetLibraryInfo needs to know the size of wchar_t to work on
functions like `wcslen`. This patch changes clang to always emit the
wchar_size module flag (it would only do so for ARM previously).
This also adds an `assert()` to ensure the LLVM defaults based on the
target triple are in sync with clang.

Differential Revision: https://reviews.llvm.org/D32982

llvm-svn: 303478
2017-05-20 01:29:55 +00:00
Chandler Carruth 93786da2cb Make '-disable-llvm-optzns' an alias for '-disable-llvm-passes'.
Much to my surprise, '-disable-llvm-optzns' which I thought was the
magical flag I wanted to get at the raw LLVM IR coming out of Clang
deosn't do that. It still runs some passes over the IR. I don't want
that, I really want the *raw* IR coming out of Clang and I strongly
suspect everyone else using it is in the same camp.

There is actually a flag that does what I want that I didn't know about
called '-disable-llvm-passes'. I suspect many others don't know about it
either. It both does what I want and is much simpler.

This removes the confusing version and makes that spelling of the flag
an alias for '-disable-llvm-passes'. I've also moved everything in Clang
to use the 'passes' spelling as it seems both more accurate (*all* LLVM
passes are disabled, not just optimizations) and much easier to remember
and spell correctly.

This is part of simplifying how Clang drives LLVM to make it cleaner to
wire up to the new pass manager.

Differential Revision: https://reviews.llvm.org/D28047

llvm-svn: 290392
2016-12-23 00:23:01 +00:00
Peter Collingbourne 25a2b70cd0 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
2016-12-13 20:50:44 +00:00
Peter Collingbourne 2849c4e841 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
2016-12-13 20:40:39 +00:00
Peter Collingbourne 4e6a540024 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
2016-03-14 19:07:10 +00:00
NAKAMURA Takumi b470942f2a Fix clang/test/CodeGenCXX/strict-vtable-pointers.cpp for -Asserts. It missed something. :)
llvm-svn: 249223
2015-10-03 00:50:12 +00:00
Piotr Padlewski 276a78d860 Emiting invariant.group.barrier for ctors bugfix
Ensure that the vptr store in the most-derived constructor is not behind
an invariant group barrier. Previously, the base-most vptr store would
be the one behind no barrier, and that could result in the creator of
the object thinking it had the base-most vtable.
This bug caused clang call pure virtual functions when called from
constructor body.

http://reviews.llvm.org/D13373

llvm-svn: 249197
2015-10-02 22:12:40 +00:00
Piotr Padlewski 9d0ecf27a7 Added llvm.module flag for strict vtable pointers
It is dangerous to do LTO on code with strict-vtable-pointers, because
one module has invariant.group.barriers, and the other one not.

In the future I want to just strip all invariant.group metadata from
vptrs loads/stores and get rid of invariant.group.barrier calls.

http://reviews.llvm.org/D12580

llvm-svn: 247724
2015-09-15 21:46:50 +00:00
Piotr Padlewski 338c9d0ade Emiting llvm.invariant.group.barrier when dynamic type changes
For more goto:
http://lists.llvm.org/pipermail/cfe-dev/2015-July/044227.html

http://reviews.llvm.org/D12312

llvm-svn: 247723
2015-09-15 21:46:47 +00:00