test: Make a start on a test suite for libLTO.

[pcc]

Summary

This works in a similar way to the gold plugin tests. We search for a compatible
linker on $PATH and use it to run tests against our just-built libLTO. To start
with, test the just added opt level functionality.

llvm/trunk/cmake/config-ix.cmake

 endif()
 
 find_program(GOLD_EXECUTABLE NAMES ld.gold ld DOC "The gold linker")
 if(GOLD_EXECUTABLE)
   set(LLVM_BINUTILS_INCDIR "" CACHE PATH
     "PATH to binutils/include containing plugin-api.h for gold plugin.")
 endif()
 
+if(APPLE)
+  find_program(LD64_EXECUTABLE NAMES ld DOC "The ld64 linker")
+endif()
+
 include(FindOCaml)
 include(AddOCaml)
 if(WIN32)
   message(STATUS "OCaml bindings disabled.")
 else()
   find_package(OCaml)
   if( NOT OCAML_FOUND )
     message(STATUS "OCaml bindings disabled.")

llvm/trunk/test/CMakeLists.txt

 if(TARGET LLVMgold)
   set(LLVM_TEST_DEPENDS ${LLVM_TEST_DEPENDS} LLVMgold)
 endif()
 
 if(TARGET llvm-go)
   set(LLVM_TEST_DEPENDS ${LLVM_TEST_DEPENDS} llvm-go)
 endif()
 
+if(APPLE)
+  set(LLVM_TEST_DEPENDS ${LLVM_TEST_DEPENDS} LTO)
+endif()
+
 if(TARGET ocaml_llvm)
   set(LLVM_TEST_DEPENDS ${LLVM_TEST_DEPENDS}
           ocaml_llvm
           ocaml_llvm_all_backends
           ocaml_llvm_analysis
           ocaml_llvm_bitreader
           ocaml_llvm_bitwriter
           ocaml_llvm_executionengine

llvm/trunk/test/Makefile

lit.site.cfg: FORCE
   @$(ECHOPATH) s=@LLVM_BINARY_DIR@=$(LLVM_OBJ_ROOT)=g >> lit.tmp
   @$(ECHOPATH) s=@LLVM_TOOLS_DIR@=$(ToolDir)=g >> lit.tmp
   @$(ECHOPATH) s=@LLVM_LIBRARY_DIR@=$(LibDir)=g >> lit.tmp
   @$(ECHOPATH) s=@SHLIBDIR@=$(SharedLibDir)=g >> lit.tmp
   @$(ECHOPATH) s=@SHLIBEXT@=$(SHLIBEXT)=g >> lit.tmp
   @$(ECHOPATH) s=@EXEEXT@=$(EXEEXT)=g >> lit.tmp
   @$(ECHOPATH) s=@PYTHON_EXECUTABLE@=$(PYTHON)=g >> lit.tmp
   @$(ECHOPATH) s=@GOLD_EXECUTABLE@=ld=g >> lit.tmp
+  @$(ECHOPATH) s=@LD64_EXECUTABLE@=ld=g >> lit.tmp
   @$(ECHOPATH) s=@OCAMLFIND@=$(OCAMLFIND)=g >> lit.tmp
   @$(ECHOPATH) s!@OCAMLFLAGS@!$(addprefix -cclib ,$(LDFLAGS))!g >> lit.tmp
   @$(ECHOPATH) s=@HAVE_OCAMLOPT@=$(HAVE_OCAMLOPT)=g >> lit.tmp
   @$(ECHOPATH) s=@HAVE_OCAML_OUNIT@=$(HAVE_OCAML_OUNIT)=g >> lit.tmp
   @$(ECHOPATH) s=@GO_EXECUTABLE@=$(GO)=g >> lit.tmp
   @$(ECHOPATH) s!@HOST_CC@!$(CC)!g >> lit.tmp
   @$(ECHOPATH) s!@HOST_CXX@!$(CXX)!g >> lit.tmp
   @$(ECHOPATH) s!@HOST_LDFLAGS@!$(LDFLAGS)!g >> lit.tmp

llvm/trunk/test/lit.cfg

 # Similarly, have a macro to use llc with DWARF even when the host is win32.
 llc_dwarf = 'llc'
 if re.search(r'win32', config.target_triple):
   llc_dwarf += ' -mtriple='+config.target_triple.replace('-win32', '-mingw32')
 config.substitutions.append( ('%llc_dwarf', llc_dwarf) )
 
 # Add site-specific substitutions.
 config.substitutions.append( ('%gold', config.gold_executable) )
+config.substitutions.append( ('%ld64', config.ld64_executable) )
 config.substitutions.append( ('%go', config.go_executable) )
 config.substitutions.append( ('%llvmshlibdir', config.llvm_shlib_dir) )
 config.substitutions.append( ('%shlibext', config.llvm_shlib_ext) )
 config.substitutions.append( ('%exeext', config.llvm_exe_ext) )
 config.substitutions.append( ('%python', config.python_executable) )
 
 # OCaml substitutions.
 # Support tests for both native and bytecode builds.
if not 'GNU gold' in ld_version.stdout.read().decode():
         return False
     ld_version.wait()
 
     return True
 
 if have_ld_plugin_support():
     config.available_features.add('ld_plugin')
 
+def have_ld64_plugin_support():
+    if config.ld64_executable == '':
+        return False
+
+    ld_cmd = subprocess.Popen([config.ld64_executable, '-v'], stderr = subprocess.PIPE)
+    ld_out = ld_cmd.stderr.read().decode()
+    ld_cmd.wait()
+
+    if 'ld64' not in ld_out or 'LTO' not in ld_out:
+        return False
+
+    return True
+
+if have_ld64_plugin_support():
+    config.available_features.add('ld64_plugin')
+
 # Ask llvm-config about assertion mode.
 try:
     llvm_config_cmd = subprocess.Popen(
         [os.path.join(llvm_tools_dir, 'llvm-config'), '--assertion-mode'],
         stdout = subprocess.PIPE,
         env=config.environment)
 except OSError:
     print("Could not find llvm-config in " + llvm_tools_dir)

llvm/trunk/test/lit.site.cfg.in

 import sys
 
 ## Autogenerated by LLVM/Clang configuration.
 # Do not edit!
 config.host_triple = "@LLVM_HOST_TRIPLE@"
 config.target_triple = "@TARGET_TRIPLE@"
 config.llvm_src_root = "@LLVM_SOURCE_DIR@"
 config.llvm_obj_root = "@LLVM_BINARY_DIR@"
 config.llvm_tools_dir = "@LLVM_TOOLS_DIR@"
 config.llvm_lib_dir = "@LLVM_LIBRARY_DIR@"
 config.llvm_shlib_dir = "@SHLIBDIR@"
 config.llvm_shlib_ext = "@SHLIBEXT@"
 config.llvm_exe_ext = "@EXEEXT@"
 config.lit_tools_dir = "@LLVM_LIT_TOOLS_DIR@"
 config.python_executable = "@PYTHON_EXECUTABLE@"
 config.gold_executable = "@GOLD_EXECUTABLE@"
+config.ld64_executable = "@LD64_EXECUTABLE@"
 config.ocamlfind_executable = "@OCAMLFIND@"
 config.have_ocamlopt = "@HAVE_OCAMLOPT@"
 config.have_ocaml_ounit = "@HAVE_OCAML_OUNIT@"
 config.ocaml_flags = "@OCAMLFLAGS@"
 config.go_executable = "@GO_EXECUTABLE@"
 config.enable_shared = @ENABLE_SHARED@
 config.enable_assertions = @ENABLE_ASSERTIONS@
 config.targets_to_build = "@TARGETS_TO_BUILD@"

llvm/trunk/test/tools/lto/lit.local.cfg

+if not 'ld64_plugin' in config.available_features:
+   config.unsupported = True

llvm/trunk/test/tools/lto/opt-level.ll

+; RUN: llvm-as %s -o %t.o
+; RUN: env DYLD_LIBRARY_PATH=%llvmshlibdir %ld64 -arch x86_64 -dylib -mllvm -O0 -o %t.dylib %t.o
+; RUN: llvm-nm -no-llvm-bc %t.dylib | FileCheck --check-prefix=CHECK-O0 %s
+; RUN: env DYLD_LIBRARY_PATH=%llvmshlibdir %ld64 -arch x86_64 -dylib -mllvm -O2 -o %t.dylib %t.o
+; RUN: llvm-nm -no-llvm-bc %t.dylib | FileCheck --check-prefix=CHECK-O2 %s
+
+target triple = "x86_64-apple-macosx10.8.0"
+
+; CHECK-O0: t _f1
+; CHECK-O2-NOT: _f1
+define internal void @f1() {
+  ret void
+}
+
+; CHECK-O0: T _f2
+; CHECK-O2: T _f2
+define void @f2() {
+  call void @f1()
+  ret void
+}