Build clang-tblgen for cross compiling; build libclang for arm64 (#190)

This should make it possible to use an Apple M1 mac to work on WebAssembly.

The trick is that for cross-compiling `libclang` we need a host `clang-tblgen` not just a host `llvm-tblgen`.

3 files changed, 17 insertions, 5 deletions

diff --git a/.gitignore b/.gitignore
index 1c8d4b15925d..603c1c1c942f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -61,3 +61,6 @@ autoconf/autom4te.cache
 /clang/utils/analyzer/projects/*/PatchedSource
 /clang/utils/analyzer/projects/*/ScanBuildResults
 /clang/utils/analyzer/projects/*/RefScanBuildResults
+
+/artifacts
+/.packages
diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index f8228a2e09d2..79dcd549e514 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -38,6 +38,7 @@ stages:
               rootfs: 
               archflag: --arch x64
               LLVMTableGenArg: 
+              ClangTableGenArg: 
             arm64:
               assetManifestOS: linux
               assetManifestPlatform: arm64
@@ -45,6 +46,7 @@ stages:
               rootfs: /crossrootfs/arm64
               archflag: --arch arm64
               LLVMTableGenArg: /p:LLVMTableGenPath=$(Build.SourcesDirectory)/artifacts/obj/BuildRoot-x64/bin/llvm-tblgen
+              ClangTableGenArg: /p:ClangTableGenPath=$(Build.SourcesDirectory)/artifacts/obj/BuildRoot-x64/bin/clang-tblgen
             arm:
               assetManifestOS: linux
               assetManifestPlatform: arm
@@ -52,6 +54,7 @@ stages:
               rootfs: /crossrootfs/arm
               archflag: --arch arm
               LLVMTableGenArg: /p:LLVMTableGenPath=$(Build.SourcesDirectory)/artifacts/obj/BuildRoot-x64/bin/llvm-tblgen
+              ClangTableGenArg: /p:ClangTableGenPath=$(Build.SourcesDirectory)/artifacts/obj/BuildRoot-x64/bin/clang-tblgen
         pool:
           ${{ if eq(variables['System.TeamProject'], 'public') }}:
             vmImage: ubuntu-20.04
@@ -73,7 +76,7 @@ stages:
           condition: and(succeeded(), ne(variables['assetManifestPlatform'], 'x64'))
 
         - bash: |
-            ./build.sh --ci --restore --build --pack $(archflag) --configuration $(_BuildConfig) $(_InternalBuildArgs) $(LLVMTableGenArg)
+            ./build.sh --ci --restore --build --pack $(archflag) --configuration $(_BuildConfig) $(_InternalBuildArgs) $(LLVMTableGenArg) $(ClangTableGenArg)
           displayName: 'Build and package'
           env:
             ROOTFS_DIR: $(rootfs)
@@ -94,11 +97,13 @@ stages:
               assetManifestPlatform: x64
               archflag: --arch x64
               LLVMTableGenArg: 
+              ClangTableGenArg: 
             arm64:
               assetManifestOS: osx
               assetManifestPlatform: arm64
               archflag: --arch arm64
               LLVMTableGenArg: /p:LLVMTableGenPath=$(Build.SourcesDirectory)/artifacts/obj/BuildRoot-x64/bin/llvm-tblgen
+              ClangTableGenArg: /p:ClangTableGenPath=$(Build.SourcesDirectory)/artifacts/obj/BuildRoot-x64/bin/clang-tblgen
         pool:
           vmImage: macOS-10.15
         steps:
@@ -114,7 +119,7 @@ stages:
           condition: and(succeeded(), ne(variables['assetManifestPlatform'], 'x64'))
 
         - bash: |
-            ./build.sh --ci --restore --build --pack $(archflag) --configuration $(_BuildConfig) $(_InternalBuildArgs) $(LLVMTableGenArg)
+            ./build.sh --ci --restore --build --pack $(archflag) --configuration $(_BuildConfig) $(_InternalBuildArgs) $(LLVMTableGenArg) $(ClangTableGenArg)
           displayName: 'Build and package'
 
         - bash: 
@@ -133,16 +138,19 @@ stages:
               assetManifestPlatform: x64
               archflag: -arch x64
               LLVMTableGenArg:
+              ClangTableGenArg:
             arm64:
               assetManifestOS: win
               assetManifestPlatform: arm64
               archflag: -arch arm64
               LLVMTableGenArg: /p:LLVMTableGenPath=$(Build.SourcesDirectory)\artifacts\obj\BuildRoot-x64\bin\llvm-tblgen.exe
+              ClangTableGenArg: /p:ClangTableGenPath=$(Build.SourcesDirectory)\artifacts\obj\BuildRoot-x64\bin\clang-tblgen.exe
             arm:
               assetManifestOS: win
               assetManifestPlatform: arm
               archflag: -arch arm
               LLVMTableGenArg: /p:LLVMTableGenPath=$(Build.SourcesDirectory)\artifacts\obj\BuildRoot-x64\bin\llvm-tblgen.exe
+              ClangTableGenArg: /p:ClangTableGenPath=$(Build.SourcesDirectory)\artifacts\obj\BuildRoot-x64\bin\clang-tblgen.exe
         pool:
           ${{ if eq(variables['System.TeamProject'], 'public') }}:
             vmImage: windows-2019
@@ -159,7 +167,7 @@ stages:
           displayName: 'Build host llvm-tblgen for cross-compiling'
           condition: and(succeeded(), ne(variables['assetManifestPlatform'], 'x64'))
 
-        - powershell: eng\build.ps1 -ci -restore -build -pack $(archflag) -configuration $(_BuildConfig) $(_InternalBuildArgs) $(LLVMTableGenArg)
+        - powershell: eng\build.ps1 -ci -restore -build -pack $(archflag) -configuration $(_BuildConfig) $(_InternalBuildArgs) $(LLVMTableGenArg) $(ClangTableGenArg)
           displayName: 'Build and package'
 
         - powershell: eng\common\build.ps1 -ci -restore -publish -configuration $(_BuildConfig) $(_InternalBuildArgs) /p:AssetManifestOS=$(assetManifestOS) /p:PlatformName=$(assetManifestPlatform) -projects $(Build.SourcesDirectory)\llvm.proj
diff --git a/llvm.proj b/llvm.proj
index 47cf4dedffa9..0be19a1d217b 100644
--- a/llvm.proj
+++ b/llvm.proj
@@ -27,7 +27,7 @@
 
     </_SetupEnvironment>
     <_CMakeConfigureCommand>$(_SetupEnvironment) cmake $(_LLVMSourceDir) -G "$(CMakeGenerator)" @(_LLVMBuildArgs->'%(Identity)',' ')</_CMakeConfigureCommand>
-    <_BuildSubset Condition="'$(BuildLLVMTableGenOnly)' == 'true'">llvm-tblgen</_BuildSubset>
+    <_BuildSubset Condition="'$(BuildLLVMTableGenOnly)' == 'true'">llvm-tblgen clang-tblgen</_BuildSubset>
     <_BuildCommand Condition="'$(CMakeGenerator)' == 'Unix Makefiles'">$(_SetupEnvironment) make $(_BuildSubset) -j$([System.Environment]::ProcessorCount)</_BuildCommand>
     <_BuildCommand Condition="'$(CMakeGenerator)' == 'Ninja'">$(_SetupEnvironment) ninja $(_BuildSubset)</_BuildCommand>
     <_CMakeInstallCommand>$(_SetupEnvironment) cmake -DCMAKE_INSTALL_DO_STRIP=1 -DCMAKE_INSTALL_PREFIX=$(_LLVMInstallDir) -P cmake_install.cmake</_CMakeInstallCommand>
@@ -50,6 +50,7 @@
     <_LLVMBuildArgs Condition="'$(TargetArchitecture)' == 'arm64' and '$(BuildOS)' == 'OSX'" Include="-DCMAKE_OSX_ARCHITECTURES=arm64"/>
     <_LLVMBuildArgs Condition="'$(TargetArchitecture)' == 'arm' or '$(TargetArchitecture)' == 'arm64'" Include="-DCMAKE_CROSSCOMPILING:BOOL=ON" />
     <_LLVMBuildArgs Condition="'$(LLVMTableGenPath)' != ''" Include='-DLLVM_TABLEGEN="$(LLVMTableGenPath)"' />
+    <_LLVMBuildArgs Condition="'$(ClangTableGenPath)' != ''" Include='-DCLANG_TABLEGEN="$(ClangTableGenPath)"' />
     <_LLVMBuildArgs Include="-DCMAKE_BUILD_TYPE=$(Configuration)" />
     <_LLVMBuildArgs Include="-DLLVM_BUILD_LLVM_C_DYLIB:BOOL=OFF" />
     <_LLVMBuildArgs Include="-DLLVM_ENABLE_DIA_SDK:BOOL=OFF" />
@@ -70,7 +71,7 @@
     <_LLVMBuildArgs Condition="'$(BuildOS)' == 'Windows_NT'" Include='-DLLVM_USE_CRT_RELEASE=MT' />
   </ItemGroup>
 
-  <ItemGroup Condition="'$(TargetArchitecture)' != 'arm' and '$(TargetArchitecture)' != 'arm64'">
+  <ItemGroup Condition="'$(BuildOS)' == 'OSX' or ('$(TargetArchitecture)' != 'arm' and '$(TargetArchitecture)' != 'arm64')">
     <_LLVMBuildArgs Include='-DLLVM_ENABLE_PROJECTS=clang' />
     <_LLVMBuildArgs Include='-DCLANG_BUILD_TOOLS:BOOL=OFF' />
     <_LLVMBuildArgs Include='-DCLANG_INCLUDE_TESTS:BOOL=OFF' />