In the past we have been using `DataType` in PrimExpr.dtype field to
check type information for PrimExpr while still having BaseExpr.ty for
richer type information. DataType is also used both in runtime and
compiler. This PR streamlines the boundary:
- PrimExpr.ty now carries PrimType that replaces original use of
`DataType`
- Runtime use will now favor DLPack DLDataType, removing one layer of
indirection.
- Constants attributes where values are usually runtime values, will use
`DLDataType`
- DataType will be phased out after this PR
We also brings up helper functions in PrimType, but also limits them to
a more concise set so the functions do not grow with the data type codes
in DLPack.
This is a major refactor that changes the IR primitive. It helps to
bring possible future benefits:
- Unified type mechanism through Expr.ty
- Possibility of carry future Type nodes
Migration Guide:
- Use `PrimType` when code reasons about compiler expression types,
tensor element compiler types, or constructs a `PrimExpr`/compiler type.
- Use existing source types such as `expr.ty()`, `ExprOp.expr_ty()`, or
TE tensor element `dtype` where possible instead of rebuilding a type
from dtype text.
- Use raw `DLDataType` for runtime constants, ABI paths, dtype-valued
attrs, and storage/runtime helper logic.
- Prefer direct `PrimType` equality, `MatchesCode(...)`,
`MatchesElementType(...)`, and `WithCode(...)` over local wrappers or
string dtype checks.
Performance:
Using Object type instead of DLDataType would indeed bring some
performance impact to the IR. We have done the following performance
optimizations:
- Make sure most of the outputs reuse one of the PrimType from inputs
- Cache a thread local PrimType based on input so we don't repeatly
realloc
We did benchmarks show that rewrite simplify operation stays within
+-10% overhead of original one. Which merits the refactor given the
benefit the unfication brings
## 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.
This PR brings up the tirx namespace. We have been spliting out the
original tir namespace to include high-level component s_tir and this PR
updates the remaining low-level part as tirx namespace
## Summary
This PR introduces `AllocBufferNode`/`AllocBuffer` as a single TIR
statement that both allocates memory and declares a buffer into scope.
This replaces the previous pattern of `Allocate(var, dtype, shape, cond,
DeclBuffer(buf, body))` with the simpler `AllocBuffer(buf, body)`.
### Main changes
- **New IR node** `AllocBufferNode` with fields `{buffer, annotations,
body}` — same semantics as `DeclBuffer` but also allocates memory
- **TVMScript**: `T.alloc_buffer(shape, dtype, scope)` now emits
`AllocBuffer` directly (statement-level allocation).
`T.sblock_alloc_buffer(...)` for SBlock-level buffer allocation (full
parameter set)
- **All codegen backends** (C, CUDA, Metal, OpenCL, WebGPU, LLVM, NVPTX,
AMDGPU, SPIR-V) updated to handle `AllocBufferNode`
- **All TIR transforms** (storage_rewrite, flatten_buffer,
vectorize_loop, lower_warp_memory, etc.) updated
- **All S-TIR transforms** (compact_buffer_region, merge_shared_memory,
inject_double_buffer, etc.) updated
- **Removed `AllocateNode`** entirely — `AllocBuffer` is now the sole
allocation primitive
- **Removed `AllocDescriptor`** from merge_shared_memory_allocations —
uses `Buffer` objects directly
- **Added `AllocBuffer::ConstantAllocationSize()`** inline helper method
### Design rationale
The old `Allocate + DeclBuffer` pair was a historical artifact:
`AllocateNode` stored raw fields (`buffer_var`, `dtype`, `extents`,
`condition`) separate from the `Buffer` object, requiring pattern
matching (`IsAllocateDeclBufferPattern`) to reconstruct the buffer
association. `AllocBuffer` unifies this into a single node with a proper
`Buffer` reference, simplifying codegen backends and transform passes.
225 files changed, ~3500 insertions/deletions (net near-zero, mostly
mechanical migration).
## Test plan
- [x] All TIR base tests pass
- [x] All TIR transform tests pass
- [x] TVMScript roundtrip tests pass
- [x] S-TIR transform tests pass
- [x] Codegen tests pass
- [x] All-platform minimal tests pass
- [x] C++ functor tests pass
- [x] Pre-commit clean (clang-format, ruff, etc.)
This PR renames tir.Block to SBlock. This clearly indicate the
scheduable property of the block and is a prereq for followup stir
passes refactor.
Main changes:
- Data structure change from Block to SBlock
- Syntax change from T.block to T.sblock
The current unittest folder is too large and contains too many files and
too many components. This PR refactors the unittest folder by moving the
files to the corresponding folders.
Tianqi Chen