This implements the minimum amout of support for this feature
to get the test/AST/ms-constexpr.cpp test working. More has to
be added to get SemaCXX tests to work.
Add an `EvaluationResult` class. This contains the result either as a
`Pointer` or as a `APValue`.
This way, we can inspect the result of the evaluation and diagnose
problems with it (e.g. uninitialized fields in global initializers or
pointers pointing to things they shouldn't point to).
Static lambdas cannot have captures. They may still end up in the
constant evaluator though. They've been diagnosted appropriately before,
so just reject them here.
This is similar to #74661, but for the new constant expression
interpreter.
This patch replaces endianness::native with llvm::endianness::native.
Note that endianness::native would rely on:
using endianness = llvm::endianness;
in llvm/include/llvm/Support/Endian.h.
The Floating class wraps a APFloat, which might heap allocate memory to
represent large floating values. When writing those to bytecode, we
would free() the heap allocation after writing, when destroying the
actual APFloat we wrote.
Fix this by seralizing a Floating as Semantics + APInt.
This will be neccessary in more cases later, when we support
arbitrary-precision integers or _BitInt.
Differential Revision: https://reviews.llvm.org/D155165
We pass these as pointers, so we need to be careful not to emit pointers
to pointers when we emit visit DeclRefExprs pointing to parameters.
Differential Revision: https://reviews.llvm.org/D153695
Make our Function class keep a list of parameter offsets so we can
simply get a parameter by index when evaluating builtin functions.
Differential Revision: https://reviews.llvm.org/D149816
'Params' is a member of the ByteCodeEmitter. We only added the
parameters the first time we saw the function, so subsequent visits
didn't work if they had (and used) parameters.
Just do the work everytime we see a function.
Differential Revision: https://reviews.llvm.org/D141681
Since we now handle functions without a body as well, we can't just use
getHasBody() anymore. Funtions that haven't been defined yet are those
that don't have a body *and* aren't valid.
Also, just pass the information about whether the Function has a body or
not along from the FunctionDecl.
Differential Revision: https://reviews.llvm.org/D141591
This reverts commit aaf73ae266db44fce107a0b73fcb33527bfb52eb.
This breaks sanitized builds because the constructor is called with an
unaligned address.
This way we're invoking the copy constructor, which might be necessary
if the argument is not trivially constructible.
Differential Revision: https://reviews.llvm.org/D138554
Implement passing the this pointer to member functions and constructors.
The this pointer is passed via the stack. This changes the functions to
explicitly track whether they have a RVO pointer and a this pointer.
Differential Revision: https://reviews.llvm.org/D134699
This is illegal in a constexpr context. We can already figure that out,
but we'd still run into an assertion later on when trying to visit the
missing initializer or run the invalid function.
Differential Revision: https://reviews.llvm.org/D132832
The Clang interpreter's bytecode uses a packed stream of bytes
representation, but also wants to have some opcodes take pointers as
arguments, which are currently embedded in the bytecode directly.
However, CHERI, and thus Arm's upcoming experimental Morello prototype,
provide spatial memory safety for C/C++ by implementing language-level
(and sub-language-level) pointers as capabilities, which track bounds,
permissions and validity in hardware. This uses tagged memory with a
single tag bit at every capability-aligned address, and so storing
pointers to unaligned addresses results in the tag being stripped,
leading to a tag fault when the pointer is ultimately dereferenced at a
later point.
In order to support a stricter C/C++ implementation like CHERI, we no
longer store pointers directly in the bytecode, instead storing them in
a table and embedding the index in the bytecode.
Reviewed By: nand
Differential Revision: https://reviews.llvm.org/D97606
Summary:
This patch introduces the skeleton of the constexpr interpreter,
capable of evaluating a simple constexpr functions consisting of
if statements. The interpreter is described in more detail in the
RFC. Further patches will add more features.
Reviewers: Bigcheese, jfb, rsmith
Subscribers: bruno, uenoku, ldionne, Tyker, thegameg, tschuett, dexonsmith, mgorny, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D64146
llvm-svn: 371834
Breaks BUILD_SHARED_LIBS build, introduces cycles in library dependency
graphs. (clangInterp depends on clangAST which depends on clangInterp)
This reverts r370839, which is an yet another recommit of D64146.
llvm-svn: 370874
Summary:
This patch introduces the skeleton of the constexpr interpreter,
capable of evaluating a simple constexpr functions consisting of
if statements. The interpreter is described in more detail in the
RFC. Further patches will add more features.
Reviewers: Bigcheese, jfb, rsmith
Subscribers: bruno, uenoku, ldionne, Tyker, thegameg, tschuett, dexonsmith, mgorny, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D64146
llvm-svn: 370839
Summary:
This patch introduces the skeleton of the constexpr interpreter,
capable of evaluating a simple constexpr functions consisting of
if statements. The interpreter is described in more detail in the
RFC. Further patches will add more features.
Reviewers: Bigcheese, jfb, rsmith
Subscribers: bruno, uenoku, ldionne, Tyker, thegameg, tschuett, dexonsmith, mgorny, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D64146
llvm-svn: 370636
