d80d3a358f
This revision refactors ElementsAttr into an Attribute Interface.
This enables a common interface with which to interact with
element attributes, without needing to modify the builtin
dialect. It also removes a majority (if not all?) of the need for
the current OpaqueElementsAttr, which was originally intended as
a way to opaquely represent data that was not representable by
the other builtin constructs.
The new ElementsAttr interface not only allows for users to
natively represent their data in the way that best suits them,
it also allows for efficient opaque access and iteration of the
underlying data. Attributes using the ElementsAttr interface
can directly expose support for interacting with the held
elements using any C++ data type they claim to support. For
example, DenseIntOrFpElementsAttr supports iteration using
various native C++ integer/float data types, as well as
APInt/APFloat, and more. ElementsAttr instances that refer to
DenseIntOrFpElementsAttr can use all of these data types for
iteration:
```c++
DenseIntOrFpElementsAttr intElementsAttr = ...;
ElementsAttr attr = intElementsAttr;
for (uint64_t value : attr.getValues<uint64_t>())
...;
for (APInt value : attr.getValues<APInt>())
...;
for (IntegerAttr value : attr.getValues<IntegerAttr>())
...;
```
ElementsAttr also supports failable range/iterator access,
allowing for selective code paths depending on data type
support:
```c++
ElementsAttr attr = ...;
if (auto range = attr.tryGetValues<uint64_t>()) {
for (uint64_t value : *range)
...;
}
```
Differential Revision: https://reviews.llvm.org/D109190
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|---|---|---|
| .. | ||
| deps_impl | ||
| examples | ||
| llvm-project-overlay | ||
| llvm_configs | ||
| third_party_build | ||
| .bazelignore | ||
| .bazelrc | ||
| .bazelversion | ||
| .gitignore | ||
| BUILD.bazel | ||
| README.md | ||
| WORKSPACE | ||
| configure.bzl | ||
| overlay_directories.py | ||
| terminfo.bzl | ||
| vulkan_sdk.bzl | ||
| zlib.bzl | ||
README.md
Introduction
Warning The Bazel build is experimental and best-effort, supported in line with the policy for LLVM's peripheral support tier. LLVM's official build system is CMake. If in doubt use that. If you make changes to LLVM, you're expected to update the CMake build but you don't need to update Bazel build files. Reviewers should not ask authors to update Bazel build files unless the author has opted in to support Bazel. Keeping the Bazel build files up-to-date is on the people who use the Bazel build.
Bazel is a multi-language build system focused on reproducible builds to enable dependency analysis and caching for fast incremental builds.
The main motivation behind the existence of an LLVM Bazel build is that a number of projects that depend on LLVM use Bazel, and Bazel works best when it knows about the whole source tree (as opposed to installing artifacts coming from another build system). Community members are also welcome to use Bazel for their own development as long as they continue to maintain the official CMake build system. See also, the proposal for adding this configuration.
Quick Start
git clone https://github.com/llvm/llvm-project.git; cd llvm-projectif you don't have a checkout yet.- Install Bazel at the version indicated by .bazelversion, following the official instructions, if you don't have it installed yet: https://docs.bazel.build/versions/master/install.html.
cd utils/bazelbazel build --config=generic_clang @llvm-project//...(if building on Unix with Clang).--config=generic_gccand--config=msvcare also available.
Configuration
The repository .bazelrc will import user-specific settings from a
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build --config=generic_clang
You can enable disk caching, which will cache build results
build --disk_cache=~/.cache/bazel-disk-cache
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build --sandbox_base=/dev/shm
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Usage
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