Use the regular code paths for interpreting.
Add new instructions: `StartSpeculation` will reset the diagnostics
pointers to `nullptr`, which will keep us from reporting any diagnostics
during speculation. `EndSpeculation` will undo this.
The rest depends on what `Emitter` we use.
For `EvalEmitter`, we have no bytecode, so we implement `speculate()` by
simply visiting the first argument of `__builtin_constant_p`. If the
evaluation fails, we push a `0` on the stack, otherwise a `1`.
For `ByteCodeEmitter`, add another instrucion called `BCP`, that
interprets all the instructions following it until the next
`EndSpeculation` instruction. If any of those instructions fails, we
jump to the `EndLabel`, which brings us right before the
`EndSpeculation`. We then push the result on the stack.
This happens a lot with `if constexpr` with a condition based on a
template param. In those cases, the condition is a ConstantExpr with a
value already set, so we can use that and ignore the other branch.
…tExpr
If the ImplicitValueInitExpr is of incomplete array type, we ignore it
in its Visit function. This is a special case here, so pull out the
element type and zero the elements.
This used to cause certain std::range tests in libc++ to be diagnosed as
modifying a const-qualified field, because we set the IsConst flag to
true unconditionally. Check the type instead.
For `new A[N]{1,2,3}`, we need to allocate N elements of type A, and
initialize the first three with the given InitListExpr elements.
However, if N is larger than 3, we need to initialize the remaining
elements with the InitListExpr array filler.
Similarly, for `new A[N];`, we need to initilize all fields with the
constructor of A. The initializer type is a CXXConstructExpr of
IncompleteArrayType in this case, which we can't generally handle.
Make lifetime management more explicit. We're only using this for
CXXPseudoDestructorExprs for now but we need this to handle
std::construct_at/placement-new after destructor calls later anyway.
Call `EvaluateAsInitializer()` explicitly here, so we don't abort the
evaluation of the `DeflRefExpr` just because the initializer of that
global variable failed.
See the comment in Compiler<>::VisitCXXThisExpr.
We need to mark the InitList explicitly, so we later know what to refer
to when the init chain is active.
Add it as another kind of pointer, saving both a `Type*` for the result
of the typeid() expression as well as one for the type of the typeid
expression.
The attached test case from
https://github.com/llvm/llvm-project/issues/117294 used to cause an
assertion because we called classifPrim() on an array type.
The new result doesn't crash but isn't exactly perfect either. Since the
problem arises when evaluating an ImplicitValueInitExpr, we have no
proper source location to point to. Point to the caller instead.
Note that PointerUnion::{is,get} have been soft deprecated in
PointerUnion.h:
// FIXME: Replace the uses of is(), get() and dyn_cast() with
// isa<T>, cast<T> and the llvm::dyn_cast<T>
I'm not touching PointerUnion::dyn_cast for now because it's a bit
complicated; we could blindly migrate it to dyn_cast_if_present, but
we should probably use dyn_cast when the operand is known to be
non-null.
