[bolt][bazel] Port e235fcb582.

utils/bazel/configure.bzl

@@ -172,10 +172,19 @@ def _llvm_configure_impl(repository_ctx):
     )
 
     # Create a starlark file with the requested LLVM targets.
-    targets = repository_ctx.attr.targets
+    llvm_targets = repository_ctx.attr.targets
     repository_ctx.file(
         "llvm/targets.bzl",
-        content = "llvm_targets = " + str(targets),
+        content = "llvm_targets = " + str(llvm_targets),
+        executable = False,
+    )
+
+    # Create a starlark file with the requested BOLT targets.
+    bolt_targets = ["AArch64","X86","RISCV"]  # Supported targets.
+    bolt_targets = [t for t in llvm_targets if t in bolt_targets]
+    repository_ctx.file(
+        "bolt/targets.bzl",
+        content = "bolt_targets = " + str(bolt_targets),
         executable = False,
     )
 

utils/bazel/llvm-project-overlay/bolt/BUILD.bazel

@@ -3,6 +3,7 @@
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
 load("@bazel_skylib//rules:expand_template.bzl", "expand_template")
+load(":targets.bzl", "bolt_targets")
 
 package(
     default_visibility = ["//visibility:public"],
@@ -16,6 +17,20 @@ genrule(
     cmd = "echo '#undef BOLT_REVISION' >> $@\n",
 )
 
+expand_template(
+    name = "target_config_def_gen",
+    out = "include/bolt/Core/TargetConfig.def",
+    substitutions = {"@BOLT_ENUM_TARGETS@": "\n".join(
+        ["BOLT_TARGET({})".format(target) for target in bolt_targets],
+    )},
+    template = "include/bolt/Core/TargetConfig.def.in",
+)
+
+cc_library(
+    name = "TargetConfig",
+    textual_hdrs = [":target_config_def_gen"],
+)
+
 cc_binary(
     name = "llvm-bolt-heatmap",
     srcs = glob([
@@ -24,6 +39,7 @@ cc_binary(
     deps = [
         ":Profile",
         ":Rewrite",
+        ":TargetConfig",
         ":Utils",
         "//llvm:AllTargetsAsmParsers",
         "//llvm:AllTargetsDisassemblers",
@@ -54,6 +70,7 @@ cc_binary(
         ":Profile",
         ":Rewrite",
         ":RuntimeLibs",
+        ":TargetConfig",
         ":TargetAArch64",
         ":TargetX86",
         ":Utils",