Add support for AArch64 target.

In cooperation with the LLVM patch, this should implement all scalar front-end
parts of the C and C++ ABIs for AArch64.

This patch excludes the NEON support also reviewed due to an outbreak of
batshit insanity in our legal department. That will be committed soon bringing
the changes to precisely what has been approved.

Further reviews would be gratefully received.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@174055 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 32 insertions, 1 deletions

diff --git a/lib/Driver/ToolChains.cpp b/lib/Driver/ToolChains.cpp
index 6f68f1c577..39f0f06de8 100644
--- a/lib/Driver/ToolChains.cpp
+++ b/lib/Driver/ToolChains.cpp
@@ -1081,6 +1081,12 @@ Generic_GCC::GCCInstallationDetector::GCCInstallationDetector(
   // Declare a bunch of static data sets that we'll select between below. These
   // are specifically designed to always refer to string literals to avoid any
   // lifetime or initialization issues.
+  static const char *const AArch64LibDirs[] = { "/lib" };
+  static const char *const AArch64Triples[] = {
+    "aarch64-none-linux-gnu",
+    "aarch64-linux-gnu"
+  };
+
   static const char *const ARMLibDirs[] = { "/lib" };
   static const char *const ARMTriples[] = {
     "arm-linux-gnueabi",
@@ -1146,6 +1152,16 @@ Generic_GCC::GCCInstallationDetector::GCCInstallationDetector(
   };
 
   switch (TargetTriple.getArch()) {
+  case llvm::Triple::aarch64:
+    LibDirs.append(AArch64LibDirs, AArch64LibDirs 
+                   + llvm::array_lengthof(AArch64LibDirs));
+    TripleAliases.append(
+      AArch64Triples, AArch64Triples + llvm::array_lengthof(AArch64Triples));
+    MultiarchLibDirs.append(
+      AArch64LibDirs, AArch64LibDirs + llvm::array_lengthof(AArch64LibDirs));
+    MultiarchTripleAliases.append(
+      AArch64Triples, AArch64Triples + llvm::array_lengthof(AArch64Triples));
+    break;
   case llvm::Triple::arm:
   case llvm::Triple::thumb:
     LibDirs.append(ARMLibDirs, ARMLibDirs + llvm::array_lengthof(ARMLibDirs));
@@ -2218,6 +2234,9 @@ static std::string getMultiarchTriple(const llvm::Triple TargetTriple,
     if (llvm::sys::fs::exists(SysRoot + "/lib/x86_64-linux-gnu"))
       return "x86_64-linux-gnu";
     return TargetTriple.str();
+  case llvm::Triple::aarch64:
+    if (llvm::sys::fs::exists(SysRoot + "/lib/aarch64-linux-gnu"))
+      return "aarch64-linux-gnu";
   case llvm::Triple::mips:
     if (llvm::sys::fs::exists(SysRoot + "/lib/mips-linux-gnu"))
       return "mips-linux-gnu";
@@ -2444,6 +2463,7 @@ void Linux::addClangTargetOptions(const ArgList &DriverArgs,
   const Generic_GCC::GCCVersion &V = GCCInstallation.getVersion();
   bool UseInitArrayDefault
     = V >= Generic_GCC::GCCVersion::Parse("4.7.0") ||
+      getTriple().getArch() == llvm::Triple::aarch64 ||
       getTriple().getEnvironment() == llvm::Triple::Android;
   if (DriverArgs.hasFlag(options::OPT_fuse_init_array,
                          options::OPT_fno_use_init_array,
@@ -2506,6 +2526,9 @@ void Linux::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
     "/usr/include/i686-linux-gnu",
     "/usr/include/i486-linux-gnu"
   };
+  const StringRef AArch64MultiarchIncludeDirs[] = {
+    "/usr/include/aarch64-linux-gnu"
+  };
   const StringRef ARMMultiarchIncludeDirs[] = {
     "/usr/include/arm-linux-gnueabi"
   };
@@ -2529,6 +2552,8 @@ void Linux::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
     MultiarchIncludeDirs = X86_64MultiarchIncludeDirs;
   } else if (getTriple().getArch() == llvm::Triple::x86) {
     MultiarchIncludeDirs = X86MultiarchIncludeDirs;
+  } else if (getTriple().getArch() == llvm::Triple::aarch64) {
+    MultiarchIncludeDirs = AArch64MultiarchIncludeDirs;
   } else if (getTriple().getArch() == llvm::Triple::arm) {
     if (getTriple().getEnvironment() == llvm::Triple::GNUEABIHF)
       MultiarchIncludeDirs = ARMHFMultiarchIncludeDirs;
diff --git a/lib/Driver/ToolChains.h b/lib/Driver/ToolChains.h
index c0a9646c28..b313ab610c 100644
--- a/lib/Driver/ToolChains.h
+++ b/lib/Driver/ToolChains.h
@@ -388,7 +388,8 @@ public:
 
   virtual bool IsIntegratedAssemblerDefault() const {
     // Default integrated assembler to on for x86.
-    return (getTriple().getArch() == llvm::Triple::x86 ||
+    return (getTriple().getArch() == llvm::Triple::aarch64 ||
+            getTriple().getArch() == llvm::Triple::x86 ||
             getTriple().getArch() == llvm::Triple::x86_64);
   }
 };
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index f925f762e5..cb7cc2381d 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -549,6 +549,7 @@ static bool isSignedCharDefault(const llvm::Triple &Triple) {
   default:
     return true;
 
+  case llvm::Triple::aarch64:
   case llvm::Triple::arm:
   case llvm::Triple::ppc:
   case llvm::Triple::ppc64:
@@ -5578,6 +5579,8 @@ void linuxtools::Link::ConstructJob(Compilation &C, const JobAction &JA,
   CmdArgs.push_back("-m");
   if (ToolChain.getArch() == llvm::Triple::x86)
     CmdArgs.push_back("elf_i386");
+  else if (ToolChain.getArch() == llvm::Triple::aarch64)
+    CmdArgs.push_back("aarch64linux");
   else if (ToolChain.getArch() == llvm::Triple::arm
            ||  ToolChain.getArch() == llvm::Triple::thumb)
     CmdArgs.push_back("armelf_linux_eabi");
@@ -5626,6 +5629,8 @@ void linuxtools::Link::ConstructJob(Compilation &C, const JobAction &JA,
       CmdArgs.push_back("/system/bin/linker");
     else if (ToolChain.getArch() == llvm::Triple::x86)
       CmdArgs.push_back("/lib/ld-linux.so.2");
+    else if (ToolChain.getArch() == llvm::Triple::aarch64)
+      CmdArgs.push_back("/lib/ld-linux-aarch64.so.1");
     else if (ToolChain.getArch() == llvm::Triple::arm ||
              ToolChain.getArch() == llvm::Triple::thumb) {
       if (ToolChain.getTriple().getEnvironment() == llvm::Triple::GNUEABIHF)