This relands https://github.com/llvm/llvm-project/pull/135119, after
fixing crashes seen in LLDB CI reported here:
https://github.com/llvm/llvm-project/pull/135119#issuecomment-2794910840
Fixes https://github.com/llvm/llvm-project/pull/135119
This changes the TemplateArgument representation to hold a flag
indicating whether a tempalte argument of expression type is supposed to
be canonical or not.
This gets one step closer to solving
https://github.com/llvm/llvm-project/issues/92292
This still doesn't try to unique as-written TSTs. While this would
increase the amount of memory savings and make code dealing with the AST
more well-behaved, profiling template argument lists is still too
expensive for this to be worthwhile, at least for now.
This also fixes the context creation of TSTs, so that they don't in some
cases get incorrectly flagged as sugar over their own canonical form.
This is captured in the test expectation change of some AST dumps.
This fixes some places which were unnecessarily canonicalizing these
TSTs.
One was "unsafe use of bool" and the other was "sign comparision
mismatch", and both were because we're treating a bool object as if it
were an unsigned int. Add a cast to make that more explicit.
This changes the TemplateArgument representation to hold a flag
indicating whether a template argument of expression type is supposed to
be canonical or not.
This gets one step closer to solving
https://github.com/llvm/llvm-project/issues/92292
This still doesn't try to unique as-written TSTs. While this would
increase the amount of memory savings and make code dealing with the AST
more well-behaved, profiling template argument lists is still too
expensive for this to be worthwhile, at least for now. Without this
uniquing, this patch stands neutral in terms of performance impact.
This also fixes the context creation of TSTs, so that they don't in some
cases get incorrectly flagged as sugar over their own canonical form.
This is captured in the test expectation change of some AST dumps.
This fixes some places which were unnecessarily canonicalizing these
TSTs.
Currently when printing a template argument of expression type, the
expression is converted immediately into a string to be sent to the
diagnostic engine, unsing a fake LangOpts.
This makes the expression printing look incorrect for the current
language, besides being inneficient, as we don't actually need to print
the expression if the diagnostic would be ignored.
This fixes a nastiness with the TemplateArgument constructor for
expressions being implicit, and all current users just passing an
expression to a diagnostic were implicitly going through the template
argument path.
The expressions are also being printed unquoted. This will be fixed in a
subsequent patch, as the test churn is much larger.
This fixes partial ordering of pack expansions of NTTPs, by procedding
with the check using the pattern of the NTTP through the rules of the
non-pack case.
This also unifies almost all of the different versions of
FinishTemplateArgumentDeduction (except the function template case).
This makes sure they all follow the rules consistently, instantiating
the parameters and comparing those with the argument.
Fixes#132562
Fix#134356.
We accidentally skipped checking derived-to-base conversions because
deduction did not strip sugar in the relevant code. This caused
deduction failures when a parameter type had an attribute.
This introduces a new class 'UnsignedOrNone', which models a lite
version of `std::optional<unsigned>`, but has the same size as
'unsigned'.
This replaces most uses of `std::optional<unsigned>`, and similar
schemes utilizing 'int' and '-1' as sentinel.
Besides the smaller size advantage, this is simpler to serialize, as its
internal representation is a single unsigned int as well.
This reverts an earlier attempt
(adb0d8ddceb143749c519d14b8b31b481071da77 and
50e5411e4247421fd606f0a206682fcdf0303ae3) to support these expansions,
which was limited to type arguments and which subverted the purpose
of SubstTemplateTypeParmType.
This propagates the ArgumentPackSubstitutionIndex along with the
AssociatedConstraint, so that the pack expansion works, without
needing any new transforms or otherwise any changes to the template
instantiation process.
This keeps the tests from the reverted commits, and adds a few more
showing the new solution also works for NTTPs.
Fixes https://github.com/llvm/llvm-project/issues/131798
It turns out that TemplateParamsReferencedInTemplateArgumentList() and
MarkUsedTemplateParameters() have the similar goal, so let's drop the
hand-written ASTVisitor.
Original PR: #130537
Originally reverted due to revert of dependent commit. Relanding with no
changes.
This changes the MemberPointerType representation to use a
NestedNameSpecifier instead of a Type to represent the base class.
Since the qualifiers are always parsed as nested names, there was an
impedance mismatch when converting these back and forth into types, and
this led to issues in preserving sugar.
The nested names are indeed a better match for these, as the differences
which a QualType can represent cannot be expressed syntatically, and
they represent the use case more exactly, being either dependent or
referring to a CXXRecord, unqualified.
This patch also makes the MemberPointerType able to represent sugar for
a {up/downcast}cast conversion of the base class, although for now the
underlying type is canonical, as preserving the sugar up to that point
requires further work.
As usual, includes a few drive-by fixes in order to make use of the
improvements.
Original PR: #130537
Reland after updating lldb too.
This changes the MemberPointerType representation to use a
NestedNameSpecifier instead of a Type to represent the base class.
Since the qualifiers are always parsed as nested names, there was an
impedance mismatch when converting these back and forth into types, and
this led to issues in preserving sugar.
The nested names are indeed a better match for these, as the differences
which a QualType can represent cannot be expressed syntatically, and
they represent the use case more exactly, being either dependent or
referring to a CXXRecord, unqualified.
This patch also makes the MemberPointerType able to represent sugar for
a {up/downcast}cast conversion of the base class, although for now the
underlying type is canonical, as preserving the sugar up to that point
requires further work.
As usual, includes a few drive-by fixes in order to make use of the
improvements.
This changes the MemberPointerType representation to use a
NestedNameSpecifier instead of a Type to represent the class.
Since the qualifiers are always parsed as nested names, there was an
impedance mismatch when converting these back and forth into types, and
this led to issues in preserving sugar.
The nested names are indeed a better match for these, as the differences
which a QualType can represent cannot be expressed syntactically, and it
also represents the use case more exactly, being either dependent or
referring to a CXXRecord, unqualified.
This patch also makes the MemberPointerType able to represent sugar for
a {up/downcast}cast conversion of the base class, although for now the
underlying type is canonical, as preserving the sugar up to that point
requires further work.
As usual, includes a few drive-by fixes in order to make use of the
improvements, and removing some duplications, for example
CheckBaseClassAccess is deduplicated from across SemaAccess and
SemaCast.
When checking the template template parameters of template template
parameters, the PartialOrdering context was not correctly propagated.
This also has a few drive-by fixes, such as checking the template
parameter lists of template template parameters, which was previously
missing and would have been it's own bug, but we need to fix it in order
to prevent crashes in error recovery in a simple way.
Fixes#130362
Instead of manually adding a note pointing to the relevant template
parameter to every relevant error, which is very easy to miss, this
patch adds a new instantiation context note, so that this can work using
RAII magic.
This fixes a bunch of places where these notes were missing, and is more
future-proof.
Some diagnostics are reworked to make better use of this note:
- Errors about missing template arguments now refer to the parameter
which is missing an argument.
- Template Template parameter mismatches now refer to template
parameters as parameters instead of arguments.
It's likely this will add the note to some diagnostics where the
parameter is not super relevant, but this can be reworked with time and
the decrease in maintenance burden makes up for it.
This bypasses the templight dumper for the new context entry, as the
tests are very hard to update.
This depends on #125453, which is needed to avoid losing the context
note for errors occuring during template argument deduction.
This skips the provisional resolution of CWG1432 just when ordering the
candidates for function call code completion, as otherwise this breaks
some assumptions the implementation makes about how closely related the
candidates are.
As a drive-by, deduplicate the implementation with the one used for
class template partial ordering, and strenghten an assertion which was
previosuly dependent on the order of candidates.
Also add a test for the fix for CWG1432 when partial ordering function
templates, which was otherwise untested.
Fixes#125500
Sometimes number of expressions in InitListExpr is used for template
argument deduction. So, in these cases we need to pay attention to real
number of expressions including expanded #embed data.
Fixes https://github.com/llvm/llvm-project/issues/122306
Class templates might be only instantiated when they are required to be
complete, but checking the template args against the primary template is
immediate.
This result is cached so that later when the class is instantiated,
checking against the primary template is not repeated.
The 'MatchedPackOnParmToNonPackOnArg' flag is also produced upon
checking against the primary template, so it needs to be cached in the
specialziation as well.
This fixes a bug which has not been in any release, so there are no
release notes.
Fixes#125290
This fixes instantiation of definition for friend function templates,
when the declaration found and the one containing the definition have
different template contexts.
In these cases, the the function declaration corresponding to the
definition is not available; it may not even be instantiated at all.
So this patch adds a bit which tracks which function template
declaration was instantiated from the member template. It's used to find
which primary template serves as a context for the purpose of
obtainining the template arguments needed to instantiate the definition.
Fixes#55509
Relanding patch, with no changes, after it was reverted due to revert of
commit this patch depended on.
In deduction, when comparing template arguments of value kind, we should
check if the value matches. Values of different types can still match.
For example, `short(0)` matches `int(0)`.
Values of nullptr kind always match each other, since there is only one
such possible value. Similarly to integrals, the type does not matter.
This fixes the core issue described in P3579, following the design
intent of P0522 to not introduce any new cases where a template template
parameter match is allowed for a template which is not valid for all
possible uses.
With this patch, narrowing conversions are disallowed for TTP matching.
This reuses the existing machinery for diagnosing narrowing in a
converted constant expression.
Since P0522 is a DR and we apply it all the way back to C++98, this
brings that machinery to use in older standards, in this very narrow
scope of TTP matching.
This still doesn't solve the ambiguity when partial ordering NTTPs of
different integral types, this is blocked by a different bug which will
be fixed in a subsequent patch (but the test cases are added).
This patch relands the following PRs:
* #111711
* #107350
* #111457
All of these patches were reverted due to an issue reported in
https://github.com/llvm/llvm-project/pull/111711#issuecomment-2406491485,
due to interdependencies.
---
[clang] Finish implementation of P0522
This finishes the clang implementation of P0522, getting rid
of the fallback to the old, pre-P0522 rules.
Before this patch, when partial ordering template template parameters,
we would perform, in order:
* If the old rules would match, we would accept it. Otherwise, don't
generate diagnostics yet.
* If the new rules would match, just accept it. Otherwise, don't
generate any diagnostics yet again.
* Apply the old rules again, this time with diagnostics.
This situation was far from ideal, as we would sometimes:
* Accept some things we shouldn't.
* Reject some things we shouldn't.
* Only diagnose rejection in terms of the old rules.
With this patch, we apply the P0522 rules throughout.
This needed to extend template argument deduction in order
to accept the historial rule for TTP matching pack parameter to non-pack
arguments.
This change also makes us accept some combinations of historical and P0522
allowances we wouldn't before.
It also fixes a bunch of bugs that were documented in the test suite,
which I am not sure there are issues already created for them.
This causes a lot of changes to the way these failures are diagnosed,
with related test suite churn.
The problem here is that the old rules were very simple and
non-recursive, making it easy to provide customized diagnostics,
and to keep them consistent with each other.
The new rules are a lot more complex and rely on template argument
deduction, substitutions, and they are recursive.
The approach taken here is to mostly rely on existing diagnostics,
and create a new instantiation context that keeps track of this context.
So for example when a substitution failure occurs, we use the error
produced there unmodified, and just attach notes to it explaining
that it occurred in the context of partial ordering this template
argument against that template parameter.
This diverges from the old diagnostics, which would lead with an
error pointing to the template argument, explain the problem
in subsequent notes, and produce a final note pointing to the parameter.
---
[clang] CWG2398: improve overload resolution backwards compat
With this change, we discriminate if the primary template and which partial
specializations would have participated in overload resolution prior to
P0522 changes.
We collect those in an initial set. If this set is not empty, or the
primary template would have matched, we proceed with this set as the
candidates for overload resolution.
Otherwise, we build a new overload set with everything else, and proceed
as usual.
---
[clang] Implement TTP 'reversed' pack matching for deduced function template calls.
Clang previously missed implementing P0522 pack matching
for deduced function template calls.
This patch partially implements CWG2369 for non-lambda-constrained
functions.
Lambdas are left intact at this point because we need extra work to
correctly instantiate captures before the function instantiation.
As a premise of CWG2369, this patch also implements CWG2770 to ensure
the function parameters are instantiated on demand.
Closes https://github.com/llvm/llvm-project/issues/54440
In the case where a type-constraint on an NTTP contains a pack, we form
a PackExpansionType to model it. However, there are a few places
expecting it to be a non-pack expansion, and luckily only small changes
could make them work.
Fixes https://github.com/llvm/llvm-project/issues/88866
Summary:
Address spaces are used in several embedded and GPU targets to describe
accesses to different types of memory. Currently we use the address
space enumerations to control which address spaces are considered
supersets of eachother, however this is also a target level property as
described by the C standard's passing mentions. This patch allows the
address space checks to use the target information to decide if a
pointer conversion is legal. For AMDGPU and NVPTX, all supported address
spaces can be converted to the default address space.
More semantic checks can be added on top of this, for now I'm mainly
looking to get more standard semantics working for C/C++. Right now the
address space conversions must all be done explicitly in C/C++ unlike
the offloading languages which define their own custom address spaces
that just map to the same target specific ones anyway. The main question
is if this behavior is a function of the target or the language.
Currently, we store injected template arguments in
`RedeclarableTemplateDecl::CommonBase`. This approach has a couple
problems:
1. We can only access the injected template arguments of
`RedeclarableTemplateDecl` derived types, but other `Decl` kinds still
make use of the injected arguments (e.g.
`ClassTemplatePartialSpecializationDecl`,
`VarTemplatePartialSpecializationDecl`, and `TemplateTemplateParmDecl`).
2. Accessing the injected template arguments requires the common data
structure to be allocated. This may occur before we determine whether a
previous declaration exists (e.g. when comparing constraints), so if the
template _is_ a redeclaration, we end up discarding the common data
structure.
This patch moves the storage and access of injected template arguments
from `RedeclarableTemplateDecl` to `TemplateParameterList`.
Translates `RWBuffer` and `StructuredBuffer` resources buffer types to
DirectX target types `dx.TypedBuffer` and `dx.RawBuffer`.
Includes a change of `HLSLAttributesResourceType` from 'sugar' type to
full canonical type. This is required for codegen and other clang
infrastructure to work property on HLSL resource types.
Fixes#95952 (part 2/2)
This patch reapplies #111173, fixing a bug when instantiating dependent
expressions that name a member template that is later explicitly
specialized for a class specialization that is implicitly instantiated.
The bug is addressed by adding the `hasMemberSpecialization` function,
which return `true` if _any_ redeclaration is a member specialization.
This is then used when determining the instantiation pattern for a
specialization of a template, and when collecting template arguments for
a specialization of a template.
With this change, we discriminate if the primary template and which
partial specializations would have participated in overload resolution
prior to P0522 changes.
We collect those in an initial set. If this set is not empty, or the
primary template would have matched, we proceed with this set as the
candidates for overload resolution.
Otherwise, we build a new overload set with everything else, and proceed
as usual.
