Commit Graph

23 Commits

Author SHA1 Message Date
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
Reid Kleckner fb93154bf1 [MS] Don't escape MS C++ names with \01
It is not needed after LLVM r327734. Now it will be easier to copy-paste
IR symbol names from Clang.

llvm-svn: 327738
2018-03-16 20:36:49 +00:00
Rafael Espindola 922f2aa9b2 Bring r325915 back.
The tests that failed on a windows host have been fixed.

Original message:

Start setting dso_local for COFF.

With this there are still some GVs where we don't set dso_local
because setGVProperties is never called. I intend to fix that in
followup commits. This is just the bare minimum to teach
shouldAssumeDSOLocal what it should do for COFF.

llvm-svn: 325940
2018-02-23 19:30:48 +00:00
Rafael Espindola 43ce3a3a4d Revert "Start setting dso_local for COFF."
This reverts commit r325915.

It will take some time to fix the failures on a windows host.

llvm-svn: 325929
2018-02-23 18:09:29 +00:00
Rafael Espindola 004d240b6a Start setting dso_local for COFF.
With this there are still some GVs where we don't set dso_local
because setGVProperties is never called. I intend to fix that in
followup commits. This is just the bare minimum to teach
shouldAssumeDSOLocal what it should do for COFF.

llvm-svn: 325915
2018-02-23 15:32:32 +00:00
Peter Collingbourne ea21100272 IRGen: Move vtable load after argument evaluation.
This change reduces the live range of the loaded function pointer,
resulting in a slight code size decrease (~10KB in clang), and also
improves the security of CFI for virtual calls by making it less
likely that the function pointer will be spilled, and ensuring that
it is not spilled across a function call boundary.

Fixes PR35353.

Differential Revision: https://reviews.llvm.org/D42725

llvm-svn: 324286
2018-02-05 23:09:13 +00:00
Volodymyr Sapsai 17ebdb239f Reland "[CodeGen] Fix crash when a function taking transparent union is redeclared."
When a function taking transparent union is declared as taking one of
union members earlier in the translation unit, clang would hit an
"Invalid cast" assertion during EmitFunctionProlog. This case
corresponds to function f1 in test/CodeGen/transparent-union-redecl.c.
We decided to cast i32 to union because after merging function
declarations function parameter type becomes int,
CGFunctionInfo::ArgInfo type matches with ABIArgInfo type, so we decide
it is a trivial case. But these types should also be castable to
parameter declaration type which is not the case here.

Now the fix is in converting from ABIArgInfo type to VarDecl type and using
argument demotion when necessary.

Additional tests in Sema/transparent-union.c capture current behavior and make
sure there are no regressions.

rdar://problem/34949329

Reviewers: rjmccall, rafael

Reviewed By: rjmccall

Subscribers: aemerson, cfe-commits, kristof.beyls, ahatanak

Differential Revision: https://reviews.llvm.org/D41311

llvm-svn: 323156
2018-01-22 22:29:24 +00:00
Volodymyr Sapsai 22b00ec42e Revert "[CodeGen] Fix crash when a function taking transparent union is redeclared."
This reverts commit r321296. It caused performance regressions
FAIL: imp.execution_time
FAIL: 2007-01-04-KNR-Args.execution_time
FAIL: sse_expandfft.execution_time
FAIL: sse_stepfft.execution_time

llvm-svn: 321306
2017-12-21 20:52:59 +00:00
Volodymyr Sapsai 614f3702d9 [CodeGen] Fix crash when a function taking transparent union is redeclared.
When a function taking transparent union is declared as taking one of
union members earlier in the translation unit, clang would hit an
"Invalid cast" assertion during EmitFunctionProlog. This case
corresponds to function f1 in test/CodeGen/transparent-union-redecl.c.
We decided to cast i32 to union because after merging function
declarations function parameter type becomes int,
CGFunctionInfo::ArgInfo type matches with ABIArgInfo type, so we decide
it is a trivial case. But these types should also be castable to
parameter declaration type which is not the case here.

The fix is in checking for the trivial case if ABIArgInfo type matches with
parameter declaration type. It exposed inconsistency that we check
hasScalarEvaluationKind for different types in EmitParmDecl and
EmitFunctionProlog, and comment says they should match.

Additional tests in Sema/transparent-union.c capture current behavior and make
sure there are no regressions.

rdar://problem/34949329

Reviewers: rjmccall, rafael

Reviewed By: rjmccall

Subscribers: aemerson, cfe-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D41311

llvm-svn: 321296
2017-12-21 19:42:37 +00:00
Reid Kleckner 06239e42c6 [MS] Apply adjustments after storing 'this'
Summary:
The MS ABI convention is that the 'this' pointer on entry is the address
of the vfptr that was used to make the virtual method call. In other
words, the pointer on entry always points to the base subobject that
introduced the virtual method. Consider this hierarchy:

  struct A { virtual void f() = 0; };
  struct B { virtual void g() = 0; };
  struct C : A, B {
    void f() override;
    void g() override;
  };

On entry to C::g, [ER]CX will contain the address of C's B subobject,
and C::g will have to subtract sizeof(A) to recover a pointer to C.

Before this change, we applied this adjustment in the prologue and
stored the new value into the "this" local variable alloca used for
debug info. However, MSVC does not do this, presumably because it is
often profitable to fold the adjustment into later field accesses. This
creates a problem, because the debugger expects the variable to be
unadjusted. Unfortunately, CodeView doesn't have anything like DWARF
expressions for computing variables that aren't in the program anymore,
so we have to declare 'this' to be the unadjusted value if we want the
debugger to see the right value.

This has the side benefit that, in optimized builds, the 'this' pointer
will usually be available on function entry because it doesn't require
any adjustment.

Reviewers: hans

Subscribers: aprantl, cfe-commits

Differential Revision: https://reviews.llvm.org/D40109

llvm-svn: 318440
2017-11-16 19:09:36 +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
David Blaikie a953f2825b Update Clang tests to handle explicitly typed load changes in LLVM.
llvm-svn: 230795
2015-02-27 21:19:58 +00:00
David Blaikie 218b783192 Update Clang tests to handle explicitly typed gep changes in LLVM.
llvm-svn: 230783
2015-02-27 19:18:17 +00:00
Reid Kleckner 8d58513da4 Cast vtable address points to i32 (...)** to enable more globalopt
We currently use i32 (...)** as the type of the vptr field in the LLVM
struct type. LLVM's GlobalOpt prefers any bitcasts to be on the side of
the data being stored rather than on the pointer being stored to.

Reviewers: majnemer

Differential Revision: http://reviews.llvm.org/D5916

llvm-svn: 223267
2014-12-03 21:00:21 +00:00
Hans Wennborg c9bd88e681 Remove the -cxx-abi command-line flag.
This makes the C++ ABI depend entirely on the target: MS ABI for -win32 triples,
Itanium otherwise. It's no longer possible to do weird combinations.

To be able to run a test with a specific ABI without constraining it to a
specific triple, new substitutions are added to lit: %itanium_abi_triple and
%ms_abi_triple can be used to get the current target triple adjusted to the
desired ABI. For example, if the test suite is running with the i686-pc-win32
target, %itanium_abi_triple will expand to i686-pc-mingw32.

Differential Revision: http://llvm-reviews.chandlerc.com/D2545

llvm-svn: 199250
2014-01-14 19:35:09 +00:00
Rafael Espindola 442ecd22ca Add -mconstructor aliases to some tests.
clang-cl adds these, so this makes the tests a bit more realistic. These are the
tests where it would make a difference if the windows specific handling were
removed.

llvm-svn: 194336
2013-11-09 23:05:07 +00:00
Timur Iskhodzhanov 827365ea8f Use GEPs correctly when adjusting this in MicrosoftCXXABI
Reviewed at http://llvm-reviews.chandlerc.com/D1977

llvm-svn: 193176
2013-10-22 18:15:24 +00:00
Timur Iskhodzhanov 62082b7e0b [-cxx-abi microsoft] Fix this argument/parameter offsets for virtual destructors in the presence of virtual bases
Reviewed at http://llvm-reviews.chandlerc.com/D1939

llvm-svn: 192822
2013-10-16 18:24:06 +00:00
Timur Iskhodzhanov 428d042828 Quick-fix the test for no-asserts build
llvm-svn: 191534
2013-09-27 17:07:56 +00:00
Timur Iskhodzhanov 8b5987eba5 Abstract out the emission of vtables, add basic support for vtable emission when using -cxx-abi microsoft
Reviewed at http://llvm-reviews.chandlerc.com/D1532

llvm-svn: 191523
2013-09-27 14:48:01 +00:00
Timur Iskhodzhanov 88fd439a24 Abstract out virtual calls and virtual function prologue code generation; implement them for -cxx-abi microsoft
llvm-svn: 188870
2013-08-21 06:25:03 +00:00