[gn build] Support compiler-rt/profile on Windows

[aeubanks]

create and use stage2 toolchain

[thakis]

Nice :) lg with comment addresed.

llvm/utils/gn/secondary/BUILD.gn

16–17

I guess this can go now? Either just add current_os == "win" here for now instead of adding the dep above, or remove this if here

[aeubanks]

remove redundant //compiler-rt

llvm/utils/gn/build/toolchain/BUILD.gn

if (host_os == "mac") {
   stage2_unix_toolchain("stage2_iossim_x64") {
     toolchain_args = {
       current_os = "ios"
       current_cpu = "x64"
     }
   }
 }
 
-toolchain("win") {
+template("win_toolchain") {
+  toolchain(target_name) {
+    # https://groups.google.com/a/chromium.org/d/msg/gn-dev/F_lv5T-tNDM
+    forward_variables_from(invoker.toolchain_args, "*")
+    not_needed("*")
+
+    forward_variables_from(invoker, "*")
+
     cl = "cl"
     link = "link"
 
     if (clang_base_path != "") {
       cl = rebase_path(clang_base_path, root_build_dir) + "/bin/clang-cl"
       if (use_lld) {
         link = rebase_path(clang_base_path, root_build_dir) + "/bin/lld-link"
       }
     }
 
     if (use_goma) {
       cl = "$goma_dir/gomacc $cl"
     }
 
     tool("cc") {
       command = "$cl /nologo /showIncludes /Fo{{output}} /c {{source}} {{defines}} {{include_dirs}} {{cflags}} {{cflags_c}}"
       depsformat = "msvc"
       description = "CC {{output}}"
       outputs = [ "{{source_out_dir}}/{{label_name}}.{{source_name_part}}.obj" ]
     }
 
     tool("cxx") {
       command = "$cl /nologo /showIncludes /Fo{{output}} /c {{source}} {{defines}} {{include_dirs}} {{cflags}} {{cflags_cc}}"
       depsformat = "msvc"
       description = "CXX {{output}}"
       outputs = [ "{{source_out_dir}}/{{label_name}}.{{source_name_part}}.obj" ]
     }
 
     tool("alink") {
       command = "$link /lib /nologo {{arflags}} /out:{{output}} {{inputs}}"
       description = "LIB {{output}}"
       outputs = [ "{{output_dir}}/{{target_output_name}}.lib" ]
       default_output_dir = "{{root_out_dir}}/lib"
     }
 
     tool("solink") {
       outprefix = "{{output_dir}}/{{target_output_name}}"
       dllfile = "$outprefix{{output_extension}}"
       libfile = "$outprefix.lib"
       pdbfile = "$outprefix.pdb"
       command = "$link /nologo /dll {{ldflags}} /out:$dllfile /implib:$libfile /pdb:$pdbfile {{inputs}} {{libs}} "
       description = "LINK $dllfile"
       link_output = libfile
       depend_output = libfile
       runtime_outputs = [ dllfile ]
       outputs = [
         dllfile,
         libfile,
       ]
       lib_switch = ""
       default_output_extension = ".dll"
       restat = true
 
       # Put dlls next to the executables in bin/ on Windows, since Windows
       # doesn't have a configurable rpath. This matches initialization of
       # module_dir to bin/ in AddLLVM.cmake's set_output_directory().
       default_output_dir = "{{root_out_dir}}/bin"
     }
 
     # Plugins for opt and clang and so on don't work in LLVM's Windows build
     # since the code doesn't have export annotations, but there are a few
     # standalone loadable modules used for unit-testing LLVM's dynamic library
     # loading code.
     tool("solink_module") {
       outprefix = "{{output_dir}}/{{target_output_name}}"
       dllfile = "$outprefix{{output_extension}}"
       pdbfile = "$outprefix.pdb"
       command = "$link /nologo /dll {{ldflags}} /out:$dllfile /pdb:$pdbfile {{inputs}} {{libs}} "
       description = "LINK_MODULE $dllfile"
       outputs = [ dllfile ]
       lib_switch = ""
       runtime_outputs = outputs
       default_output_extension = ".dll"
 
       # No default_output_dir, all clients set output_dir.
     }
 
     tool("link") {
       outprefix = "{{output_dir}}/{{target_output_name}}"
       outfile = "$outprefix{{output_extension}}"
       pdbfile = "$outprefix.pdb"
       command = "$link /nologo {{ldflags}} /out:$outfile /pdb:$pdbfile {{inputs}} {{libs}}"
       description = "LINK $outfile"
       outputs = [ outfile ]
       lib_switch = ""
       default_output_extension = ".exe"
 
       # Setting this allows targets to override the default executable output by
       # setting output_dir.
       default_output_dir = "{{root_out_dir}}/bin"
     }
 
     tool("copy") {
       # GN hands out slash-using paths, but cmd's copy needs backslashes.
       # Use cmd's %foo:a=b% substitution feature to convert.
       command = "cmd /c set source=\"{{source}}\" & set output=\"{{output}}\" & call copy /Y %source:/=\% %output:\=/% > nul"
       description = "COPY {{source}} {{output}}"
     }
 
     tool("stamp") {
       command = "cmd /c type nul > {{output}}"
       description = "STAMP {{output}}"
     }
+  }
+}
 
+win_toolchain("win") {
   toolchain_args = {
     current_os = "win"
     current_cpu = host_cpu
   }
 }
+
+win_toolchain("stage2_win") {
+  toolchain_args = {
+    current_os = host_os
+    current_cpu = host_cpu
+
+    clang_base_path = root_build_dir
+    use_goma = false
+  }
+  deps = [
+    "//:clang($host_toolchain)",
+    "//:lld($host_toolchain)",
+  ]
+}

llvm/utils/gn/secondary/BUILD.gn

 import("//clang/lib/ARCMigrate/enable.gni")
 import("//clang/lib/StaticAnalyzer/Frontend/enable.gni")
 import("//llvm/utils/gn/build/toolchain/compiler.gni")
 
 group("default") {
   deps = [
     "//clang-tools-extra/clangd/test",
     "//clang-tools-extra/test",
     "//clang/test",
     "//clang/tools/scan-build",
+    "//compiler-rt",
     "//compiler-rt/include",
     "//compiler-rt/lib/scudo",
     "//lld/test",
     "//llvm/test",
   ]
-  if (current_os == "linux" || current_os == "mac") {
-    deps += [ "//compiler-rt" ]
-  }
   if (current_os == "linux") {
     deps += [
       "//libcxx",
       "//libcxxabi",
       "//libunwind",
     ]
   }
   if (current_os == "linux" || current_os == "android") {
     deps += [ "//compiler-rt/test/hwasan" ]

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

 import("//llvm/lib/Target/targets.gni")
 import("//llvm/utils/gn/build/mac_sdk.gni")
 import("//llvm/utils/gn/build/toolchain/compiler.gni")
 
 # In the GN build, compiler-rt is always built by just-built clang and lld.
 # FIXME: For macOS and iOS builds, depend on lib in all needed target arch
 # toolchains and then lipo them together for the final output.
+if (current_os == "win") {
+  supported_toolchains = [ "//llvm/utils/gn/build/toolchain:stage2_win" ]
+} else {
   supported_toolchains = [ "//llvm/utils/gn/build/toolchain:stage2_unix" ]
+}
 if (android_ndk_path != "") {
   supported_toolchains += [
     "//llvm/utils/gn/build/toolchain:stage2_android_aarch64",
     "//llvm/utils/gn/build/toolchain:stage2_android_arm",
   ]
 }
 group("compiler-rt") {
   deps = []

llvm/utils/gn/secondary/compiler-rt/lib/BUILD.gn

 group("lib") {
-  deps = [
+  deps = [ "//compiler-rt/lib/profile" ]
+  if (current_os != "win") {
+    deps += [
       "//compiler-rt/lib/asan",
       "//compiler-rt/lib/builtins",
-    "//compiler-rt/lib/profile",
       "//compiler-rt/lib/tsan",
     ]
   }
+}

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"
+} 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)
 }