llvm-project/utils/bazel/llvm-project-overlay/llvm/tblgen.bzl

82 lines
3.2 KiB
Python

# This file is licensed under the Apache License v2.0 with LLVM Exceptions.
# See https://llvm.org/LICENSE.txt for license information.
# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
"""This file contains BUILD extensions for generating source code from LLVM's
table definition files using the TableGen tool.
See http://llvm.org/cmds/tblgen.html for more information on the TableGen
tool.
TODO(chandlerc): Currently this expresses include-based dependencies as
"sources", and has no transitive understanding due to these files not being
correctly understood by the build system.
"""
def gentbl(
name,
tblgen,
td_file,
td_srcs,
tbl_outs,
library = True,
tblgen_args = "",
**kwargs):
"""gentbl() generates tabular code from a table definition file.
Args:
name: The name of the build rule for use in dependencies.
tblgen: The binary used to produce the output.
td_file: The primary table definitions file.
td_srcs: A list of table definition files included transitively.
tbl_outs: A list of tuples (opts, out), where each opts is a string of
options passed to tblgen, and the out is the corresponding output file
produced.
library: Whether to bundle the generated files into a library.
tblgen_args: Extra arguments string to pass to the tblgen binary.
**kwargs: Keyword arguments to pass to subsidiary cc_library() rule.
"""
llvm_project_execroot_path = Label("//llvm:tblgen.bzl").workspace_root
if td_file not in td_srcs:
td_srcs += [td_file]
for (opts, out) in tbl_outs:
rule_suffix = "_".join(opts.replace("-", "_").replace("=", "_").split(" "))
native.genrule(
name = "%s_%s_genrule" % (name, rule_suffix),
srcs = td_srcs,
outs = [out],
tools = [tblgen],
message = "Generating code from table: %s" % td_file,
cmd = (("$(location %s) -I %s/llvm/include " +
"-I %s/clang/include " +
"-I $$(dirname $(location %s)) " +
"%s $(location %s) %s -o $@") % (
tblgen,
llvm_project_execroot_path,
llvm_project_execroot_path,
td_file,
opts,
td_file,
tblgen_args,
)),
)
# For now, all generated files can be assumed to comprise public interfaces.
# If this is not true, you should specify library = False
# and list the generated '.inc' files in "srcs".
if library:
native.cc_library(
name = name,
# FIXME: This should be `textual_hdrs` instead of `hdrs`, but
# unfortunately that doesn't work with `strip_include_prefix`:
# https://github.com/bazelbuild/bazel/issues/12424
#
# Once that issue is fixed and released, we can switch this to
# `textual_hdrs` and remove the feature disabling the various Bazel
# features (both current and under-development) that motivated the
# distinction between these two.
hdrs = [f for (_, f) in tbl_outs],
features = ["-parse_headers", "-header_modules"],
**kwargs
)