[gn] Add Mac support to check-asan target

[lgrey]

Summary

I semi don't know what I'm doing here, but this seems to do the trick

[aeubanks]

lg with comment addressed, keep an eye on http://45.33.8.238/ after submitting

llvm/utils/gn/secondary/compiler-rt/test/asan/BUILD.gn

50

for simplicity we should just add everything from here unconditionally

[lgrey]

Unconditional tool/util deps

llvm/utils/gn/secondary/BUILD.gn

deps = [
     "//llvm/test",
   ]
   if (current_os == "linux") {
     deps += [
       "//libcxx",
       "//libcxxabi",
     ]
   }
-  if (current_os == "linux" || current_os == "win") {
+  if (current_os == "linux" || current_os == "win" || current_os=="mac") {
     deps += [ "//compiler-rt/test/asan" ]
   }
   if (current_os == "linux" || current_os == "android") {
     deps += [ "//compiler-rt/test/hwasan" ]
   }
   if (current_os == "linux" || current_os == "mac") {
     deps += [ "//libunwind" ]
   }

llvm/utils/gn/secondary/compiler-rt/target.gni

if (clang_enable_per_target_runtime_dir) {
   crt_current_out_dir = "$clang_resource_dir/lib/linux"
 
   crt_current_target_suffix = "-$crt_current_target_arch"
   if (current_os == "android") {
     crt_current_target_suffix += "-android"
   }
 } else if (current_os == "ios" || current_os == "mac") {
   crt_current_out_dir = "$clang_resource_dir/lib/darwin"
+  crt_current_target_suffix = "-$crt_current_target_arch"
 } else if (current_os == "baremetal") {
   crt_current_out_dir = "$clang_resource_dir/lib/baremetal"
   crt_current_target_suffix = "-$crt_current_target_arch"
 } else if (current_os == "win") {
   crt_current_out_dir = "$clang_resource_dir/lib/windows"
   crt_current_target_suffix = "-$crt_current_target_arch"
 } else {
   assert(false, "unimplemented current_os " + current_os)
 }

llvm/utils/gn/secondary/compiler-rt/test/asan/BUILD.gn

write_cmake_config("lit_site_cfg") {
   values = [
     "ASAN_LIT_SOURCE_DIR=" + rebase_path("."),
     "ASAN_TEST_CONFIG_SUFFIX=$crt_current_target_suffix",
     "ASAN_TEST_TARGET_CFLAGS=$target_flags_string",
     "ASAN_TEST_TARGET_CC=",
     "ASAN_TEST_BITS=64",
     "ASAN_TEST_APPLE_PLATFORM=",
     "ASAN_TEST_MIN_DEPLOYMENT_TARGET_FLAG=",
-    "ASAN_TEST_DYNAMIC=0",
     "ASAN_TEST_TARGET_ARCH=$crt_current_target_arch",
     "COMPILER_RT_ARM_THUMB=",
     "COMPILER_RT_BINARY_DIR=" + rebase_path("$root_gen_dir/compiler-rt"),
     "LIT_SITE_CFG_IN_HEADER=## Autogenerated from $input, do not edit",
   ]
+  if (host_os == "mac") {
+    values += [ "ASAN_TEST_DYNAMIC=1" ]
+  } else {
+    values += [ "ASAN_TEST_DYNAMIC=0" ]
+  }
 }
 
 if (current_toolchain != host_toolchain) {
   group("asan_toolchain") {
     deps = [
       ":lit_site_cfg",
       "//compiler-rt/include($host_toolchain)",
       "//compiler-rt/lib/asan",
       "//compiler-rt/lib/asan:ignorelist($host_toolchain)",
       "//compiler-rt/lib/profile",
       "//compiler-rt/test:lit_common_configured",
       "//llvm/tools/llvm-readobj($host_toolchain)",
       "//llvm/tools/llvm-symbolizer($host_toolchain)",
       "//llvm/utils/FileCheck($host_toolchain)",
       "//llvm/utils/count($host_toolchain)",
       "//llvm/utils/llvm-lit($host_toolchain)",
       "//llvm/utils/not($host_toolchain)",
     ]
+    if (host_os == "mac") {
+      deps += [
+        "//llvm/tools/llvm-nm($host_toolchain)",
+        "//llvm/tools/llvm-objdump($host_toolchain)",
+      ]
+    }
   }
 }
 
 supported_toolchains = []
-if (host_os == "linux") {
+if (host_os == "linux" || host_os == "mac") {
   supported_toolchains += [ "//llvm/utils/gn/build/toolchain:stage2_unix" ]
 } else if (host_os == "win") {
   supported_toolchains += [ "//llvm/utils/gn/build/toolchain:stage2_win_x64" ]
 }
 
 group("asan") {
   deps = []
   foreach(toolchain, supported_toolchains) {