utils/bazel/llvm-project-overlay/libc/libc_build_rules.bzl - llvm-project - Git at Google

 # 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

 """LLVM libc starlark rules for building individual functions."""

 load("@bazel_skylib//lib:paths.bzl", "paths")
 load("@bazel_skylib//lib:selects.bzl", "selects")
 load(":libc_configure_options.bzl", "LIBC_CONFIGURE_OPTIONS")
 load(":libc_namespace.bzl", "LIBC_NAMESPACE")
 load(":platforms.bzl", "PLATFORM_CPU_X86_64")

 def libc_common_copts():
     root_label = Label(":libc")
     libc_include_path = paths.join(root_label.workspace_root, root_label.package)
     return [
         "-I" + libc_include_path,
         "-I" + paths.join(libc_include_path, "include"),
         "-DLIBC_NAMESPACE=" + LIBC_NAMESPACE,
     ]

 def libc_release_copts():
     copts = [
         "-DLIBC_COPT_PUBLIC_PACKAGING",
         # This is used to explicitly give public symbols "default" visibility.
         # See src/__support/common.h for more information.
         "-DLLVM_LIBC_FUNCTION_ATTR='[[gnu::visibility(\"default\")]]'",
         # All other libc sources need to be compiled with "hidden" visibility.
         "-fvisibility=hidden",
         "-O3",
         "-fno-builtin",
         "-fno-lax-vector-conversions",
         "-ftrivial-auto-var-init=pattern",
         "-fno-omit-frame-pointer",
         "-fstack-protector-strong",
     ]

     platform_copts = selects.with_or({
         PLATFORM_CPU_X86_64: ["-mno-omit-leaf-frame-pointer"],
         "//conditions:default": [],
     })
     return copts + platform_copts

 def _libc_library(name, **kwargs):
     """Internal macro to serve as a base for all other libc library rules.

     Args:
       name: Target name.
       **kwargs: All other attributes relevant for the cc_library rule.
     """

     for attr in ["copts", "local_defines"]:
         if attr in kwargs:
             fail("disallowed attribute: '{}' in rule: '{}'".format(attr, name))
     native.cc_library(
         name = name,
         copts = libc_common_copts(),
         local_defines = LIBC_CONFIGURE_OPTIONS,
         linkstatic = 1,
         **kwargs
     )

 # A convenience function which should be used to list all libc support libraries.
 # Any library which does not define a public function should be listed with
 # libc_support_library.
 def libc_support_library(name, **kwargs):
     _libc_library(name = name, **kwargs)

 def libc_function(name, **kwargs):
     """Add target for a libc function.

     This macro creates an internal cc_library that can be used to test this
     function.

     Args:
       name: Target name. Typically the name of the function this target is for.
       **kwargs: Other attributes relevant for a cc_library. For example, deps.
     """

     # Builds "internal" library with a function, exposed as a C++ function in
     # the "LIBC_NAMESPACE" namespace. This allows us to test the function in the
     # presence of another libc.
     _libc_library(name = name, **kwargs)

 LibcLibraryInfo = provider(
     "All source files and textual headers for building a particular library.",
     fields = ["srcs", "textual_hdrs"],
 )

 def _get_libc_info_aspect_impl(
         target,  # @unused
         ctx):
     maybe_srcs = getattr(ctx.rule.attr, "srcs", [])
     maybe_hdrs = getattr(ctx.rule.attr, "hdrs", [])
     maybe_textual_hdrs = getattr(ctx.rule.attr, "textual_hdrs", [])
     maybe_deps = getattr(ctx.rule.attr, "deps", [])
     return LibcLibraryInfo(
         srcs = depset(
             transitive = [
                 dep[LibcLibraryInfo].srcs
                 for dep in maybe_deps
                 if LibcLibraryInfo in dep
             ] + [
                 src.files
                 for src in maybe_srcs + maybe_hdrs
             ],
         ),
         textual_hdrs = depset(
             transitive = [
                 dep[LibcLibraryInfo].textual_hdrs
                 for dep in maybe_deps
                 if LibcLibraryInfo in dep
             ] + [
                 hdr.files
                 for hdr in maybe_textual_hdrs
             ],
         ),
     )

 _get_libc_info_aspect = aspect(
     implementation = _get_libc_info_aspect_impl,
     attr_aspects = ["deps"],
 )

 def _libc_srcs_filegroup_impl(ctx):
     srcs = depset(transitive = [
         fn[LibcLibraryInfo].srcs
         for fn in ctx.attr.libs
     ])
     if ctx.attr.enforce_headers_only:
         paths = [f.short_path for f in srcs.to_list() if f.extension != "h"]
         if paths:
             fail("Unexpected non-header files: {}".format(paths))
     return DefaultInfo(files = srcs)

 _libc_srcs_filegroup = rule(
     doc = "Returns all sources for building the specified libraries.",
     implementation = _libc_srcs_filegroup_impl,
     attrs = {
         "libs": attr.label_list(
             mandatory = True,
             aspects = [_get_libc_info_aspect],
         ),
         "enforce_headers_only": attr.bool(default = False),
     },
 )

 def _libc_textual_hdrs_filegroup_impl(ctx):
     return DefaultInfo(
         files = depset(transitive = [
             fn[LibcLibraryInfo].textual_hdrs
             for fn in ctx.attr.libs
         ]),
     )

 _libc_textual_hdrs_filegroup = rule(
     doc = "Returns all textual headers for compiling the specified libraries.",
     implementation = _libc_textual_hdrs_filegroup_impl,
     attrs = {
         "libs": attr.label_list(
             mandatory = True,
             aspects = [_get_libc_info_aspect],
         ),
     },
 )

 def libc_release_library(
         name,
         libc_functions,
         weak_symbols = [],
         **kwargs):
     """Create the release version of a libc library.

     Args:
         name: Name of the cc_library target.
         libc_functions: List of functions to include in the library. They should be
             created by libc_function macro.
         weak_symbols: List of function names that should be marked as weak symbols.
         **kwargs: Other arguments relevant to cc_library.
     """

     _libc_srcs_filegroup(
         name = name + "_srcs",
         libs = libc_functions,
     )

     _libc_textual_hdrs_filegroup(
         name = name + "_textual_hdrs",
         libs = libc_functions,
     )
     native.cc_library(
         name = name + "_textual_hdr_library",
         textual_hdrs = [":" + name + "_textual_hdrs"],
     )

     weak_attributes = [
         "LLVM_LIBC_FUNCTION_ATTR_" + name + "='LLVM_LIBC_EMPTY, [[gnu::weak]]'"
         for name in weak_symbols
     ]

     native.cc_library(
         name = name,
         srcs = [":" + name + "_srcs"],
         copts = libc_common_copts() + libc_release_copts(),
         local_defines = weak_attributes + LIBC_CONFIGURE_OPTIONS,
         deps = [
             ":" + name + "_textual_hdr_library",
         ],
         **kwargs
     )

 def libc_header_library(name, hdrs, deps = [], **kwargs):
     """Creates a header-only library to share libc functionality.

     Args:
       name: Name of the cc_library target.
       hdrs: List of headers to be shared.
       deps: The list of libc_support_library dependencies if any.
       **kwargs: All other attributes relevant for the cc_library rule.
     """

     _libc_srcs_filegroup(
         name = name + "_hdr_deps",
         libs = deps,
         enforce_headers_only = True,
     )

     _libc_textual_hdrs_filegroup(
         name = name + "_textual_hdrs",
         libs = deps,
     )
     native.cc_library(
         name = name + "_textual_hdr_library",
         textual_hdrs = [":" + name + "_textual_hdrs"],
     )

     native.cc_library(
         name = name,
         hdrs = hdrs,
         # We put _hdr_deps in srcs, as they are not a part of this cc_library
         # interface, but instead are used to implement shared headers.
         srcs = [":" + name + "_hdr_deps"],
         deps = [":" + name + "_textual_hdr_library"],
         # copts don't really matter, since it's a header-only library, but we
         # need proper -I flags for header validation, which are specified in
         # libc_common_copts().
         copts = libc_common_copts(),
         **kwargs
     )

 def libc_math_function(
         name,
         additional_deps = None):
     """Add a target for a math function.

     Args:
       name: The name of the function.
       additional_deps: Other deps like helper cc_library targets used by the
                        math function.
     """
     additional_deps = additional_deps or []

     #TODO(michaelrj): Fix the floating point dependencies
     OLD_FPUTIL_DEPS = [
         ":__support_fputil_basic_operations",
         ":__support_fputil_division_and_remainder_operations",
         ":__support_fputil_fenv_impl",
         ":__support_fputil_fp_bits",
         ":__support_fputil_hypot",
         ":__support_fputil_manipulation_functions",
         ":__support_fputil_nearest_integer_operations",
         ":__support_fputil_normal_float",
         ":__support_math_extras",
         ":__support_fputil_except_value_utils",
     ]
     libc_function(
         name = name,
         srcs = ["src/math/generic/" + name + ".cpp"],
         hdrs = ["src/math/" + name + ".h"],
         deps = [":__support_common"] + OLD_FPUTIL_DEPS + additional_deps,
     )
	# 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

	"""LLVM libc starlark rules for building individual functions."""

	load("@bazel_skylib//lib:paths.bzl", "paths")
	load("@bazel_skylib//lib:selects.bzl", "selects")
	load(":libc_configure_options.bzl", "LIBC_CONFIGURE_OPTIONS")
	load(":libc_namespace.bzl", "LIBC_NAMESPACE")
	load(":platforms.bzl", "PLATFORM_CPU_X86_64")

	def libc_common_copts():
	root_label = Label(":libc")
	libc_include_path = paths.join(root_label.workspace_root, root_label.package)
	return [
	"-I" + libc_include_path,
	"-I" + paths.join(libc_include_path, "include"),
	"-DLIBC_NAMESPACE=" + LIBC_NAMESPACE,
	]

	def libc_release_copts():
	copts = [
	"-DLIBC_COPT_PUBLIC_PACKAGING",
	# This is used to explicitly give public symbols "default" visibility.
	# See src/__support/common.h for more information.
	"-DLLVM_LIBC_FUNCTION_ATTR='[[gnu::visibility(\"default\")]]'",
	# All other libc sources need to be compiled with "hidden" visibility.
	"-fvisibility=hidden",
	"-O3",
	"-fno-builtin",
	"-fno-lax-vector-conversions",
	"-ftrivial-auto-var-init=pattern",
	"-fno-omit-frame-pointer",
	"-fstack-protector-strong",
	]

	platform_copts = selects.with_or({
	PLATFORM_CPU_X86_64: ["-mno-omit-leaf-frame-pointer"],
	"//conditions:default": [],
	})
	return copts + platform_copts

	def _libc_library(name, **kwargs):
	"""Internal macro to serve as a base for all other libc library rules.

	Args:
	name: Target name.
	**kwargs: All other attributes relevant for the cc_library rule.
	"""

	for attr in ["copts", "local_defines"]:
	if attr in kwargs:
	fail("disallowed attribute: '{}' in rule: '{}'".format(attr, name))
	native.cc_library(
	name = name,
	copts = libc_common_copts(),
	local_defines = LIBC_CONFIGURE_OPTIONS,
	linkstatic = 1,
	**kwargs
	)

	# A convenience function which should be used to list all libc support libraries.
	# Any library which does not define a public function should be listed with
	# libc_support_library.
	def libc_support_library(name, **kwargs):
	_libc_library(name = name, **kwargs)

	def libc_function(name, **kwargs):
	"""Add target for a libc function.

	This macro creates an internal cc_library that can be used to test this
	function.

	Args:
	name: Target name. Typically the name of the function this target is for.
	**kwargs: Other attributes relevant for a cc_library. For example, deps.
	"""

	# Builds "internal" library with a function, exposed as a C++ function in
	# the "LIBC_NAMESPACE" namespace. This allows us to test the function in the
	# presence of another libc.
	_libc_library(name = name, **kwargs)

	LibcLibraryInfo = provider(
	"All source files and textual headers for building a particular library.",
	fields = ["srcs", "textual_hdrs"],
	)

	def _get_libc_info_aspect_impl(
	target, # @unused
	ctx):
	maybe_srcs = getattr(ctx.rule.attr, "srcs", [])
	maybe_hdrs = getattr(ctx.rule.attr, "hdrs", [])
	maybe_textual_hdrs = getattr(ctx.rule.attr, "textual_hdrs", [])
	maybe_deps = getattr(ctx.rule.attr, "deps", [])
	return LibcLibraryInfo(
	srcs = depset(
	transitive = [
	dep[LibcLibraryInfo].srcs
	for dep in maybe_deps
	if LibcLibraryInfo in dep
	] + [
	src.files
	for src in maybe_srcs + maybe_hdrs
	],
	),
	textual_hdrs = depset(
	transitive = [
	dep[LibcLibraryInfo].textual_hdrs
	for dep in maybe_deps
	if LibcLibraryInfo in dep
	] + [
	hdr.files
	for hdr in maybe_textual_hdrs
	],
	),
	)

	_get_libc_info_aspect = aspect(
	implementation = _get_libc_info_aspect_impl,
	attr_aspects = ["deps"],
	)

	def _libc_srcs_filegroup_impl(ctx):
	srcs = depset(transitive = [
	fn[LibcLibraryInfo].srcs
	for fn in ctx.attr.libs
	])
	if ctx.attr.enforce_headers_only:
	paths = [f.short_path for f in srcs.to_list() if f.extension != "h"]
	if paths:
	fail("Unexpected non-header files: {}".format(paths))
	return DefaultInfo(files = srcs)

	_libc_srcs_filegroup = rule(
	doc = "Returns all sources for building the specified libraries.",
	implementation = _libc_srcs_filegroup_impl,
	attrs = {
	"libs": attr.label_list(
	mandatory = True,
	aspects = [_get_libc_info_aspect],
	),
	"enforce_headers_only": attr.bool(default = False),
	},
	)

	def _libc_textual_hdrs_filegroup_impl(ctx):
	return DefaultInfo(
	files = depset(transitive = [
	fn[LibcLibraryInfo].textual_hdrs
	for fn in ctx.attr.libs
	]),
	)

	_libc_textual_hdrs_filegroup = rule(
	doc = "Returns all textual headers for compiling the specified libraries.",
	implementation = _libc_textual_hdrs_filegroup_impl,
	attrs = {
	"libs": attr.label_list(
	mandatory = True,
	aspects = [_get_libc_info_aspect],
	),
	},
	)

	def libc_release_library(
	name,
	libc_functions,
	weak_symbols = [],
	**kwargs):
	"""Create the release version of a libc library.

	Args:
	name: Name of the cc_library target.
	libc_functions: List of functions to include in the library. They should be
	created by libc_function macro.
	weak_symbols: List of function names that should be marked as weak symbols.
	**kwargs: Other arguments relevant to cc_library.
	"""

	_libc_srcs_filegroup(
	name = name + "_srcs",
	libs = libc_functions,
	)

	_libc_textual_hdrs_filegroup(
	name = name + "_textual_hdrs",
	libs = libc_functions,
	)
	native.cc_library(
	name = name + "_textual_hdr_library",
	textual_hdrs = [":" + name + "_textual_hdrs"],
	)

	weak_attributes = [
	"LLVM_LIBC_FUNCTION_ATTR_" + name + "='LLVM_LIBC_EMPTY, [[gnu::weak]]'"
	for name in weak_symbols
	]

	native.cc_library(
	name = name,
	srcs = [":" + name + "_srcs"],
	copts = libc_common_copts() + libc_release_copts(),
	local_defines = weak_attributes + LIBC_CONFIGURE_OPTIONS,
	deps = [
	":" + name + "_textual_hdr_library",
	],
	**kwargs
	)

	def libc_header_library(name, hdrs, deps = [], **kwargs):
	"""Creates a header-only library to share libc functionality.

	Args:
	name: Name of the cc_library target.
	hdrs: List of headers to be shared.
	deps: The list of libc_support_library dependencies if any.
	**kwargs: All other attributes relevant for the cc_library rule.
	"""

	_libc_srcs_filegroup(
	name = name + "_hdr_deps",
	libs = deps,
	enforce_headers_only = True,
	)

	_libc_textual_hdrs_filegroup(
	name = name + "_textual_hdrs",
	libs = deps,
	)
	native.cc_library(
	name = name + "_textual_hdr_library",
	textual_hdrs = [":" + name + "_textual_hdrs"],
	)

	native.cc_library(
	name = name,
	hdrs = hdrs,
	# We put _hdr_deps in srcs, as they are not a part of this cc_library
	# interface, but instead are used to implement shared headers.
	srcs = [":" + name + "_hdr_deps"],
	deps = [":" + name + "_textual_hdr_library"],
	# copts don't really matter, since it's a header-only library, but we
	# need proper -I flags for header validation, which are specified in
	# libc_common_copts().
	copts = libc_common_copts(),
	**kwargs
	)

	def libc_math_function(
	name,
	additional_deps = None):
	"""Add a target for a math function.

	Args:
	name: The name of the function.
	additional_deps: Other deps like helper cc_library targets used by the
	math function.
	"""
	additional_deps = additional_deps or []

	#TODO(michaelrj): Fix the floating point dependencies
	OLD_FPUTIL_DEPS = [
	":__support_fputil_basic_operations",
	":__support_fputil_division_and_remainder_operations",
	":__support_fputil_fenv_impl",
	":__support_fputil_fp_bits",
	":__support_fputil_hypot",
	":__support_fputil_manipulation_functions",
	":__support_fputil_nearest_integer_operations",
	":__support_fputil_normal_float",
	":__support_math_extras",
	":__support_fputil_except_value_utils",
	]
	libc_function(
	name = name,
	srcs = ["src/math/generic/" + name + ".cpp"],
	hdrs = ["src/math/" + name + ".h"],
	deps = [":__support_common"] + OLD_FPUTIL_DEPS + additional_deps,
	)