Commit Graph

11 Commits

Author SHA1 Message Date
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
John McCall 7f416cc426 Compute and preserve alignment more faithfully in IR-generation.
Introduce an Address type to bundle a pointer value with an
alignment.  Introduce APIs on CGBuilderTy to work with Address
values.  Change core APIs on CGF/CGM to traffic in Address where
appropriate.  Require alignments to be non-zero.  Update a ton
of code to compute and propagate alignment information.

As part of this, I've promoted CGBuiltin's EmitPointerWithAlignment
helper function to CGF and made use of it in a number of places in
the expression emitter.

The end result is that we should now be significantly more correct
when performing operations on objects that are locally known to
be under-aligned.  Since alignment is not reliably tracked in the
type system, there are inherent limits to this, but at least we
are no longer confused by standard operations like derived-to-base
conversions and array-to-pointer decay.  I've also fixed a large
number of bugs where we were applying the complete-object alignment
to a pointer instead of the non-virtual alignment, although most of
these were hidden by the very conservative approach we took with
member alignment.

Also, because IRGen now reliably asserts on zero alignments, we
should no longer be subject to an absurd but frustrating recurring
bug where an incomplete type would report a zero alignment and then
we'd naively do a alignmentAtOffset on it and emit code using an
alignment equal to the largest power-of-two factor of the offset.

We should also now be emitting much more aggressive alignment
attributes in the presence of over-alignment.  In particular,
field access now uses alignmentAtOffset instead of min.

Several times in this patch, I had to change the existing
code-generation pattern in order to more effectively use
the Address APIs.  For the most part, this seems to be a strict
improvement, like doing pointer arithmetic with GEPs instead of
ptrtoint.  That said, I've tried very hard to not change semantics,
but it is likely that I've failed in a few places, for which I
apologize.

ABIArgInfo now always carries the assumed alignment of indirect and
indirect byval arguments.  In order to cut down on what was already
a dauntingly large patch, I changed the code to never set align
attributes in the IR on non-byval indirect arguments.  That is,
we still generate code which assumes that indirect arguments have
the given alignment, but we don't express this information to the
backend except where it's semantically required (i.e. on byvals).
This is likely a minor regression for those targets that did provide
this information, but it'll be trivial to add it back in a later
patch.

I partially punted on applying this work to CGBuiltin.  Please
do not add more uses of the CreateDefaultAligned{Load,Store}
APIs; they will be going away eventually.

llvm-svn: 246985
2015-09-08 08:05:57 +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
John McCall 5fb5df9c83 Restructure how the driver communicates information about the
target Objective-C runtime down to the frontend:  break this
down into a single target runtime kind and version, and compute
all the relevant information from that.  This makes it
relatively painless to add support for new runtimes to the
compiler.  Make the new -cc1 flag, -fobjc-runtime=blah-x.y.z,
available at the driver level as a better and more general
alternative to -fgnu-runtime and -fnext-runtime.  This new
concept of an Objective-C runtime also encompasses what we
were previously separating out as the "Objective-C ABI", so
fragile vs. non-fragile runtimes are now really modelled as
different kinds of runtime, paving the way for better overall
differentiation.

As a sort of special case, continue to accept the -cc1 flag
-fobjc-runtime-has-weak, as a sop to PLCompatibilityWeak.

I won't go so far as to say "no functionality change", even
ignoring the new driver flag, but subtle changes in driver
semantics are almost certainly not intended.

llvm-svn: 158793
2012-06-20 06:18:46 +00:00
John McCall 9b0a7cea0f Make -fobjc-nonfragile-abi the -cc1 default, since it's the
increasingly prevailing case to the point that new features
like ARC don't even support the fragile ABI anymore.

This required a little bit of reshuffling with exceptions
because a check was assuming that ObjCNonFragileABI was
only being set in ObjC mode, and that's actually a bit
obnoxious to do.

Most, though, it involved a perl script to translate a ton
of test cases.

Mostly no functionality change for driver users, although
there are corner cases with disabling language-specific
exceptions that we should handle more correctly now.

llvm-svn: 140957
2011-10-02 01:16:38 +00:00
Chris Lattner a5f58b05e8 clang side to match the LLVM IR type system rewrite patch.
llvm-svn: 134831
2011-07-09 17:41:47 +00:00
Eli Friedman af9b325d23 For calls returning first-class aggregates, store by element instead of creating aggregate stores in common cases. This is more friendly to fast-isel.
llvm-svn: 131490
2011-05-17 21:08:01 +00:00
Fariborz Jahanian 557c1ed522 Revert r126678.
llvm-svn: 126685
2011-02-28 21:19:34 +00:00
Fariborz Jahanian 79246322a6 objc IRGen for Next runtime message API.
The prototype for objc_msgSend() is technically variadic - 
`id objc_msgSend(id, SEL, ...)`. 
But all method calls should use a prototype that matches the method, 
not the prototype for objc_msgSend itself().
// rdar://9048030

llvm-svn: 126678
2011-02-28 19:55:59 +00:00
Fariborz Jahanian 30e8d58dbd Copying result of object property reference expression
into a temporary is elidable as well.
(Finishes up radar 8291337).

llvm-svn: 114845
2010-09-27 17:30:38 +00:00
Fariborz Jahanian c60da031c5 Fix a NYI in IRGen which was due to incorrect AST
for property reference expression (of c++ object type)
in the conditional expression. Fixes // rdar://8291337

llvm-svn: 114783
2010-09-25 01:08:05 +00:00