Haiku: support for secondary arch

[kallisti5]

Summary

Enables Haiku to build llvm for secondary architectures.

[kallisti5]

Original author is "Jerome Duval <[e-mail]>" I don't have permission to modify this, can author be updated? (I don't have permission to)

[joerg]

This is absolutely not how the clang driver is supposed to work. No conditional compilation.

[kallisti5]

No worries. I was wondering if this one would match llvm's goals.
Do you see any iteration of these changes that would be accepted? (not using define's, etc)

We currently support "hybrid" operating system builds where we compile a secondary toolchain / abi.

A current functional example of this is we offer a gcc2 compiler + support libraries, and then also offer a gcc7 compiler + support libraries.

$ getarch
x86_gcc2
$ gcc --version
~gcc 2.95
$ gcc test.c -o test
$ ./test

test is a functional binary generated by gcc2 and run using the gcc2 ABI + libraries.


$ setarch x86
$ getarch
x86
$ gcc --version
~gcc 7.3
$ gcc test.c -o test
$ ./test

test is now a functional binary generated by gcc7 and run using the gcc7 ABI's + libraries

CMakeLists.txt

   message(FATAL_ERROR "Cannot disable static analyzer while enabling ARCMT or Z3")
 endif()
 
+if(DEFINED HAIKU_HYBRID_SECONDARY)
+  add_definitions(-DHAIKU_HYBRID_SECONDARY=${HAIKU_HYBRID_SECONDARY})
+endif()
+
 if(CLANG_ANALYZER_BUILD_Z3)
   find_package(Z3 4.5)
   if(Z3_FOUND)

lib/Driver/ToolChains/Haiku.cpp

 Haiku::Haiku(const Driver &D, const llvm::Triple& Triple, const ArgList &Args)
   : Generic_ELF(D, Triple, Args) {
 
+#ifdef HAIKU_HYBRID_SECONDARY
+  getProgramPaths().insert(getProgramPaths().begin(), getDriver().SysRoot
+                           + "/system/bin/" HAIKU_HYBRID_SECONDARY);
+  getFilePaths().clear();
+  getFilePaths().push_back(getDriver().SysRoot + "/system/lib/"
+                           HAIKU_HYBRID_SECONDARY);
+#endif
 }
 
 void Haiku::addLibCxxIncludePaths(const llvm::opt::ArgList &DriverArgs,

 
 void Haiku::addLibStdCxxIncludePaths(const llvm::opt::ArgList &DriverArgs,
                                      llvm::opt::ArgStringList &CC1Args) const {
+
+#ifdef HAIKU_HYBRID_SECONDARY
+  addLibStdCXXIncludePaths(getDriver().SysRoot, "/system/develop/headers"
+                     HAIKU_HYBRID_SECONDARY "/c++", getTriple().str(), "", "", "",
+                     DriverArgs, CC1Args);
+#else
   addLibStdCXXIncludePaths(getDriver().SysRoot, "/system/develop/headers/c++",
                            getTriple().str(), "", "", "", DriverArgs, CC1Args);
+#endif
 }

lib/Frontend/InitHeaderSearch.cpp

   if (HSOpts.UseBuiltinIncludes) {
     // Ignore the sys root, we *always* look for clang headers relative to
     // supplied path.
+#ifdef HAIKU_HYBRID_SECONDARY
+    // Remove version from foo/lib/clang/version
+    StringRef Ver = llvm::sys::path::filename(HSOpts.ResourceDir);
+    StringRef NoVer = llvm::sys::path::parent_path(HSOpts.ResourceDir);
+    // Remove clang from foo/lib/clang
+    StringRef Clang = llvm::sys::path::filename(NoVer);
+    SmallString<128> P = llvm::sys::path::parent_path(NoVer);
+
+    // Get foo/include/c++/v1
+    llvm::sys::path::append(P, HAIKU_HYBRID_SECONDARY, Clang, Ver);
+#else
     SmallString<128> P = StringRef(HSOpts.ResourceDir);
+#endif
     llvm::sys::path::append(P, "include");
     AddUnmappedPath(P, ExternCSystem, false);
   }

   }
 
   case llvm::Triple::Haiku:
+#ifdef HAIKU_HYBRID_SECONDARY
+    AddPath("/boot/system/non-packaged/develop/headers/" HAIKU_HYBRID_SECONDARY,
+            System, false);
+#else
     AddPath("/boot/system/non-packaged/develop/headers", System, false);
+#endif
     AddPath("/boot/system/develop/headers/os", System, false);
     AddPath("/boot/system/develop/headers/os/app", System, false);
     AddPath("/boot/system/develop/headers/os/arch", System, false);

     AddPath("/boot/system/develop/headers/bsd", System, false);
     AddPath("/boot/system/develop/headers/glibc", System, false);
     AddPath("/boot/system/develop/headers/posix", System, false);
+#ifdef HAIKU_HYBRID_SECONDARY
+    AddPath("/boot/system/develop/headers/" HAIKU_HYBRID_SECONDARY, System, false);
+    AddPath("/boot/system/develop/headers/" HAIKU_HYBRID_SECONDARY "/os", System,
+            false);
+    AddPath("/boot/system/develop/headers/" HAIKU_HYBRID_SECONDARY "/os/opengl",
+            System, false);
+#endif
     AddPath("/boot/system/develop/headers",  System, false);
     break;
   case llvm::Triple::RTEMS: