[BOLT] Combine two clang-bolt builders into one

[Amir]

Summary

Use BOLT.cmake and BOLT-PGO.cmake to run comprehensive
BOLT testing with Clang:

• clang-bolt instruments and optimizes 1st stage Clang built

with host GCC.

• stage2-clang-bolt uses optimized Clang to build 2nd stage

Clang (with PGO+LTO), then instruments/optimizes that binary.

This flow provides testing coverage of both clang-bolt-gcc
and clang-bolt-lto-pgo. BOLT is applied to GCC- and Clang-built
clang binary. Additionally, this extends BOLT testing by running
BOLT-optimized Clang to build 2nd stage Clang.

[Amir]

Tested http://157.230.108.44:8011/#/builders/54/builds/45

[Amir]

Remove extra diff context

[Amir]

Rebase

[gkistanova]

LGTM with a nit pick.

buildbot/osuosl/master/config/builders.py

2513

Do you need bolt twice in the name, at the beginning and at the end?

[Amir]

buildbot/osuosl/master/config/builders.py

2513

Yeah, maybe not. I used clang-bolt as a name for this usecase (Clang optimized by BOLT using CMake). Leaving it as -clang might make an impression it's just BOLT built with Clang. But since I'm the only one who looks at it, I'll drop -bolt at the end to remove the apparent redundancy.

buildbot/osuosl/master/config/builders.py

'factory' : BOLTBuilder.getBOLTCmakeBuildFactory(
                         "-DLLVM_APPEND_VC_REV=OFF",
                         "-DLLVM_CCACHE_BUILD=ON",
                         "-DLLVM_ENABLE_PROJECTS=clang;lld;bolt",
                         "-DLLVM_TARGETS_TO_BUILD=X86;AArch64",
                         ],
                     is_nfc=True,
                     )},
 
-    {'name': "bolt-x86_64-ubuntu-clang-bolt-gcc",
+    {'name': "bolt-x86_64-ubuntu-clang",
     'tags': ["bolt"],
     'workernames':["bolt-worker"],
-    'builddir': "bolt-x86_64-ubuntu-clang-bolt-gcc",
+    'builddir': "bolt-x86_64-ubuntu-clang",
     'factory' : BOLTBuilder.getBOLTCmakeBuildFactory(
                     bolttests=False,
                     clean=True,
-                    depends_on_projects=['bolt', 'clang', 'llvm'],
-                    cache='clang/cmake/caches/BOLT.cmake',
+                    depends_on_projects=['bolt', 'clang', 'lld', 'llvm'],
+                    caches=[
+                        'clang/cmake/caches/BOLT.cmake',
+                        'clang/cmake/caches/BOLT-PGO.cmake',
+                    ],
                     targets=['clang-bolt'],
+                    checks=['stage2-clang-bolt'],
                     extra_configure_args=[
                         "-DCMAKE_C_COMPILER=gcc",
                         "-DCMAKE_CXX_COMPILER=g++",
                         "-DLLVM_APPEND_VC_REV=OFF",
                         "-DLLVM_CCACHE_BUILD=ON",
-                        "-DBOLT_LLD_EXE=/usr/bin/ld.lld",
-                        ],
-                    )},
-
-
-    {'name': "bolt-x86_64-ubuntu-clang-bolt-lto-pgo",
-    'tags': ["bolt"],
-    'workernames':["bolt-worker"],
-    'builddir': "bolt-x86_64-ubuntu-clang-bolt-lto-pgo",
-    'factory' : BOLTBuilder.getBOLTCmakeBuildFactory(
-                    bolttests=False,
-                    clean=True,
-                    depends_on_projects=['bolt', 'clang', 'lld', 'llvm'],
-                    cache='clang/cmake/caches/BOLT-PGO.cmake',
-                    targets=['stage2-clang-bolt'],
-                    extra_configure_args=[
-                        "-DLLVM_APPEND_VC_REV=OFF",
                         "-DLLVM_ENABLE_LLD=ON",
                         "-DBOOTSTRAP_LLVM_ENABLE_LLD=ON",
                         "-DBOOTSTRAP_BOOTSTRAP_LLVM_ENABLE_LLD=ON",
-                        "-DLLVM_CCACHE_BUILD=ON",
                         "-DBOOTSTRAP_LLVM_CCACHE_BUILD=ON",
                         "-DPGO_INSTRUMENT_LTO=Thin",
                         ],
                     )},
 
     {'name': "bolt-x86_64-ubuntu-dylib",
     'tags': ["bolt"],
     'workernames':["bolt-worker"],

zorg/buildbot/builders/BOLTBuilder.py

 from buildbot.plugins import steps
 from buildbot.steps.shell import ShellCommand
 from zorg.buildbot.builders.UnifiedTreeBuilder import getLLVMBuildFactoryAndSourcecodeSteps, addCmakeSteps, addNinjaSteps
 from zorg.buildbot.commands.LitTestCommand import LitTestCommand
 from zorg.buildbot.commands.CmakeCommand import CmakeCommand
 from zorg.buildbot.conditions.FileConditions import FileExists
 from zorg.buildbot.process.factory import LLVMBuildFactory
 
 def getBOLTCmakeBuildFactory(
            clean = False,
            bolttests = False,
            is_nfc = False,
            targets = None,
            checks = None,
-           cache = None,
+           caches = None,
            extra_configure_args = None,
            env = None,
            depends_on_projects = None,
            **kwargs):
 
     if env is None:
         env = dict()
 
if bolttests:
                 alwaysUseLatest=True),
             ])
 
     # Some options are required for this build no matter what.
     CmakeCommand.applyRequiredOptions(extra_configure_args, [
         ('-G',                      'Ninja'),
         ])
 
-    if cache:
-        CmakeCommand.applyRequiredOptions(extra_configure_args, [
-            ("-C", f"../{f.monorepo_dir}/{cache}"),
-            ])
+    if caches:
+        for cache in caches:
+            extra_configure_args += [f"-C../{f.monorepo_dir}/{cache}"]
 
     addCmakeSteps(
         f,
         cleanBuildRequested=cleanBuildRequested,
         extra_configure_args=extra_configure_args,
         obj_dir=None,
         env=env,
         **kwargs)