## Motivation and context
A TIRx pointer carries two pieces of information that later lowering
needs: the pointee element type and the storage scope. Both must survive
when a pointer-producing expression is assigned to a Python name and
then used as the backing storage of a buffer.
A concrete example is accessing an mbarrier in another CTA through
distributed shared memory:
```python
ptr_ty = PointerType(PrimType("uint64"), "shared")
remote_ptr = T.reinterpret(
ptr_ty,
T.ptx.map_shared_rank(mbar.ptr_to([0]), T.int32(0)),
)
remote_mbar = T.decl_buffer(
[1], "uint64", data=remote_ptr, scope="shared"
)
```
`map_shared_rank` returns the raw `uint64` address produced by PTX
`mapa`, and `reinterpret` gives that address the intended
`PointerType(uint64, shared)`. Because `decl_buffer(data=...)` requires
a pointer `Var`, assigning the expression to `remote_ptr` should create
an immutable typed pointer binding.
Before this PR, an unannotated assignment such as `remote_ptr = <pointer
expression>` followed the same parser path as a numeric assignment. That
path allocates a mutable local scalar and therefore cannot represent a
`PointerType`. The pointer expression could not be carried as a
correctly typed `Var` into `decl_buffer` and CUDA lowering.
This PR makes an unannotated pointer-valued assignment emit a TIRx
`Bind`. The bound `Var` has exactly the type of the right-hand side,
including its element type and storage scope. Pointer bindings are
immutable, so reassignment in the same scope is diagnosed; shadowing a
name supplied through `extra_vars` remains valid. Numeric assignments
keep their existing mutable-local behavior.
## Type propagation fixes
The parser fix exposed several other boundaries where pointer type
information must remain consistent:
| Boundary | Previous behavior | Behavior after this PR |
| --- | --- | --- |
| Unannotated pointer assignment | Tried to materialize the value as a
local scalar | Emits an immutable `Bind` with the RHS `PointerType` |
| `address_of(buffer)` / `buffer.ptr_to(...)` | Reused the raw backing
pointer type | Returns a pointer to `buffer.dtype` while preserving the
backing pointer storage scope |
| `tvm_access_ptr` / `ptr_byte_offset` | Accepted strings or annotation
expressions, but not a `PrimType` object directly | Accepts `PrimType`
and produces the corresponding typed pointer |
| Printed `T.ptx.mapa` call | The printer emits all intrinsic attributes
positionally, but the Python helper required keyword-only arguments |
Accepts the canonical printed form so pointer code round-trips through
TVMScript |
The `address_of` distinction matters for typed views over byte-addressed
storage. For example, if a `float32` buffer is backed by a `uint8*`
allocation in `shared.dyn`, the address of a buffer element must be
`PointerType(float32, shared.dyn)`, not `PointerType(uint8,
shared.dyn)`.
With these changes, the DSMEM example above round-trips through
TVMScript and CUDA codegen declares the remote buffer pointer as
`uint64_t*`.
## TMA dtype normalization
This PR also contains a small, separate type-representation fix in TMA
descriptor construction. `TmaPlan.elem_dtype` is a string consumed by
the host-side `runtime.cuTensorMapEncodeTiled` packed call, but
`_assemble_plan` stored `g_buf.dtype`, which is a `PrimType`. Converting
it with `str(g_buf.dtype)` ensures that the generated packed-call
argument is `StringImm("float16")` rather than an IR type object. This
does not change the pointer-binding semantics described above.
## Testing
- Verify that an unannotated pointer expression creates a `Bind` whose
`Var` type matches the RHS type.
- Verify that pointer reassignment is rejected while shadowing an
`extra_vars` name is allowed.
- Verify parser/printer structural round-tripping for the pointer
binding and canonical `T.ptx.mapa` call.
- Verify that `address_of` uses the logical buffer element type and
preserves the storage scope for byte-backed buffer views.
- Verify that `tvm_access_ptr` and `ptr_byte_offset` accept `PrimType`
inputs.
- Compile the DSMEM `map_shared_rank` example through the CUDA TIRx
pipeline and check for a typed `uint64_t*` remote buffer pointer.
- Verify that the TMA host initialization passes the descriptor dtype as
a `StringImm`.
This PR removes the suite-wide TIRx compute-capability gate and
localizes hardware skips to CUDA codegen and tile-primitive tests. It
keeps the original test parameterization unchanged, allowing parser,
printer, IR, transform, and other non-hardware TIRx tests to run in
regular CI while device-dependent cases are skipped when SM100 hardware
is unavailable. CUDA codegen helpers use explicit target architectures
where needed, and the run-only benchmark utility tests retain a local
SM100 gate.
This intentionally avoids adding separate compile/run parameter cases. A
follow-up PR can audit slow frontend execution tests and define a
focused runtime regression budget for real TIRx kernels.
Local validation:
- `pytest -n auto -m "not gpu" tests/python/tirx`: 486 passed, 79
skipped.
- `pytest -n auto -m gpu tests/python/tirx` without matching hardware:
1509 skipped.
- Pre-commit passed on all changed files.
## Summary
- Make `PrimExpr` a typed C++ view over `Expr` values whose
`ExprNode::ty` is `PrimType`, instead of using a separate runtime node
class as the proof of primitive-ness.
- Use the shared `ir::Call` node for Relax, TIRX, and primitive-valued
calls, while keeping primitive-only APIs explicit at their semantic
boundaries.
- Keep Python on the general `Expr` surface for primitive-typed values
so `isinstance` behavior does not imply a nominal primitive-expression
subclass.
## Design Rationale
The main advantage of this change is that common expression nodes such
as `Call` can be unified without specializing each one to `PrimType`. A
single `ir::Call` can represent a Relax tensor call, a Relax scalar
call, or a primitive-valued intrinsic call; the result type stored in
`ExprNode::ty` determines whether that particular value can be viewed as
`PrimExpr`.
This keeps the IR node hierarchy focused on expression structure rather
than result-type categories. Nodes that are intrinsically primitive,
such as integer and floating-point literals or TIRX primitive operators,
still have strongly typed C++ APIs and data structures. General nodes
whose result type may vary, such as `Call`, remain general `Expr` nodes
and are narrowed to `PrimExpr` only where primitive-only semantics are
required.
The PR also keeps the compatibility surface practical: C++
primitive-only APIs continue to accept `PrimExpr`, Python exposes a
compatibility predicate for checking the primitive typed category, and
visitors/printers use one natural `Call` path rather than duplicating
Relax and primitive call handling. Missing expression types are
represented explicitly with `Type::Missing()` so constructors can leave
type inference to later analysis without relying on nullable `Type`
values.
## Summary
Follow-up work on top of the TIRx infrastructure bring-up (#19581). It
extends the TIRx operator-dispatch, codegen, and TVMScript surfaces with
the next batch of low-level programming features for Blackwell-class
GPUs, while keeping `s_tir` script support intact.
## Main Changes
- **op-dispatch**: warp `ldmatrix`/`stmatrix` copy dispatch; split CUDA
copy into register / gmem-smem / `ldgsts` paths; `tcgen05.ld/st`
`.16x{64,128,256}b` dispatch with a factory and M=128 layout;
element-wise broadcast at the layout level with a copy vec-alignment
fix.
- **gemm**: CUDA synchronous `mma.sync` tensor-core dispatch; accept a
Layout F C operand for M=64 MMAs.
- **op**: add the `permute_layout` primitive (replaces `permute_dims`).
- **tvmscript**: add the `Tx.jit` decorator, `Tx.constexpr` compile-time
params, and `Tx.wg_reg_tile`.
- **lower-tirx**: introduce the `Tx.device_entry()` marker (replacing
`ScopeKind::kKernel`); canonical thread filters that drop the
`Tx.filter` wrapper.
- **codegen**: add a typed-pointer byte-offset intrinsic; remove the
`entry_cluster_sync` codegen attribute.
## Validation
- `pre-commit run` (changed files) — clean
- `ninja -C build -j$(nproc)` — builds
- `pytest tests/python/tirx/ -n 16`
- `1997 passed, 39 skipped, 3 xpassed`
- `python -m pytest tests/python/all-platform-minimal-test`
- `37 passed, 105 skipped`
- `TVM_TEST_TARGETS=llvm pytest tests/python/tirx-analysis
tests/python/tirx-base tests/python/tirx-transform -n 16`
- `630 passed, 25 skipped, 8 xfailed, 1 xpassed`
## Local CI Notes
Several full CI-equivalent jobs are not locally reproducible because
this machine is missing parts of the Apache TVM CI environment (e.g.,
specific `llvm-config` versions, Vulkan, ROCm, ARM/QEMU cross-toolchain,
and web/wasm components). The Blackwell/Trainium kernel tests are
maintained downstream and are intentionally not part of this PR.
## Summary
This PR adds the initial TIRx support needed for low-level programming
of Blackwell-class GPU architectures. As part of the ongoing TIRx
refactor, it introduces TVMScript support for directly scripting
advanced hardware features without relying on scheduling as the primary
programming interface.
The change keeps existing `s_tir` script support intact while making
direct scripting a first-class path for TIRx programs.
## Main Changes
- Add TIRx operator dispatch and layout infrastructure.
- Add TVMScript support for new low-level TIRx operations.
- Add analysis, transform, and lowering support for TIRx IR nodes.
- Add CUDA/Blackwell-oriented codegen and intrinsic coverage.
- Add Python and C++ integration points for TIRx scripting and runtime
support.
## Validation
- `pre-commit run --all-files`
- `ninja -C build -j32`
- `CUDA_VISIBLE_DEVICES=2 pytest tests/python/tirx/ -n 16`
- `1723 passed, 47 skipped, 32 warnings`
- `CUDA_VISIBLE_DEVICES=2 python -m pytest -v
tests/python/all-platform-minimal-test`
- `37 passed, 105 skipped`
- `TVM_TEST_TARGETS=llvm python -m pytest -v tests/python/tirx-analysis
tests/python/tirx-base tests/python/tirx-transform -n 16`
- `664 passed, 25 skipped, 9 xfailed, 1 xpassed`
## Local CI Notes
Some full CI-equivalent jobs were not locally reproducible because this
machine is missing parts of the Apache TVM CI environment, including
`llvm-config-15/17`, Vulkan, ROCm, Maven, Sphinx, Doxygen, Emscripten,
and ARM/QEMU cross-toolchain components. Metal-specific tests were
skipped locally because no Metal runtime is available.
Hongyi Jin