ARM64: initial clang support commit.

This adds Clang support for the ARM64 backend. There are definitely
still some rough edges, so please bring up any issues you see with
this patch.

As with the LLVM commit though, we think it'll be more useful for
merging with AArch64 from within the tree.

llvm-svn: 205100

1 files changed, 66 insertions, 4 deletions

diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index 0c397584d93..f354d7c4070 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -471,6 +471,7 @@ static bool isSignedCharDefault(const llvm::Triple &Triple) {
 
   case llvm::Triple::aarch64:
   case llvm::Triple::aarch64_be:
+  case llvm::Triple::arm64:
   case llvm::Triple::arm:
   case llvm::Triple::armeb:
   case llvm::Triple::ppc:
@@ -846,6 +847,59 @@ void Clang::AddARMTargetArgs(const ArgList &Args,
     }
 }
 
+/// getARM64TargetCPU - Get the (LLVM) name of the ARM64 cpu we are targeting.
+static std::string getARM64TargetCPU(const ArgList &Args) {
+  // If we have -mcpu=, use that.
+  if (Arg *A = Args.getLastArg(options::OPT_mcpu_EQ)) {
+    StringRef MCPU = A->getValue();
+    // Handle -mcpu=native.
+    if (MCPU == "native")
+      return llvm::sys::getHostCPUName();
+    else
+      return MCPU;
+  }
+
+  // At some point, we may need to check -march here, but for now we only
+  // one arm64 architecture.
+
+  // Default to "cyclone" CPU.
+  return "cyclone";
+}
+
+void Clang::AddARM64TargetArgs(const ArgList &Args,
+                               ArgStringList &CmdArgs) const {
+  std::string TripleStr = getToolChain().ComputeEffectiveClangTriple(Args);
+  llvm::Triple Triple(TripleStr);
+
+  if (!Args.hasFlag(options::OPT_mred_zone, options::OPT_mno_red_zone, true) ||
+      Args.hasArg(options::OPT_mkernel) ||
+      Args.hasArg(options::OPT_fapple_kext))
+    CmdArgs.push_back("-disable-red-zone");
+
+  if (!Args.hasFlag(options::OPT_mimplicit_float,
+                    options::OPT_mno_implicit_float, true))
+    CmdArgs.push_back("-no-implicit-float");
+
+  const char *ABIName = 0;
+  if (Arg *A = Args.getLastArg(options::OPT_mabi_EQ))
+    ABIName = A->getValue();
+  else if (Triple.isOSDarwin())
+    ABIName = "darwinpcs";
+  else
+    ABIName = "aapcs";
+
+  CmdArgs.push_back("-target-abi");
+  CmdArgs.push_back(ABIName);
+
+  CmdArgs.push_back("-target-cpu");
+  CmdArgs.push_back(Args.MakeArgString(getARM64TargetCPU(Args)));
+
+  if (Args.hasArg(options::OPT_mstrict_align)) {
+    CmdArgs.push_back("-backend-option");
+    CmdArgs.push_back("-arm64-strict-align");
+  }
+}
+
 // Get CPU and ABI names. They are not independent
 // so we have to calculate them together.
 static void getMipsCPUAndABI(const ArgList &Args,
@@ -2325,8 +2379,8 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   // Note that these flags are trump-cards. Regardless of the order w.r.t. the
   // PIC or PIE options above, if these show up, PIC is disabled.
   llvm::Triple Triple(TripleStr);
-  if (KernelOrKext &&
-      (!Triple.isiOS() || Triple.isOSVersionLT(6)))
+  if (KernelOrKext && (!Triple.isiOS() || Triple.isOSVersionLT(6) ||
+                       Triple.getArch() == llvm::Triple::arm64))
     PIC = PIE = false;
   if (Args.hasArg(options::OPT_static))
     PIC = PIE = false;
@@ -2649,6 +2703,10 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
     AddARMTargetArgs(Args, CmdArgs, KernelOrKext);
     break;
 
+  case llvm::Triple::arm64:
+    AddARM64TargetArgs(Args, CmdArgs);
+    break;
+
   case llvm::Triple::mips:
   case llvm::Triple::mipsel:
   case llvm::Triple::mips64:
@@ -4876,6 +4934,7 @@ const char *arm::getLLVMArchSuffixForARM(StringRef CPU) {
     .Case("cortex-m3", "v7m")
     .Case("cortex-m4", "v7em")
     .Case("swift", "v7s")
+    .Case("cyclone", "v8")
     .Cases("cortex-a53", "cortex-a57", "v8")
     .Default("");
 }
@@ -4910,6 +4969,7 @@ llvm::Triple::ArchType darwin::getArchTypeForMachOArchName(StringRef Str) {
     .Cases("arm", "armv4t", "armv5", "armv6", "armv6m", llvm::Triple::arm)
     .Cases("armv7", "armv7em", "armv7k", "armv7m", llvm::Triple::arm)
     .Cases("armv7s", "xscale", llvm::Triple::arm)
+    .Case("arm64", llvm::Triple::arm64)
     .Case("r600", llvm::Triple::r600)
     .Case("nvptx", llvm::Triple::nvptx)
     .Case("nvptx64", llvm::Triple::nvptx64)
@@ -6711,7 +6771,8 @@ static StringRef getLinuxDynamicLinker(const ArgList &Args,
   } else if (ToolChain.getArch() == llvm::Triple::x86 ||
              ToolChain.getArch() == llvm::Triple::sparc)
     return "/lib/ld-linux.so.2";
-  else if (ToolChain.getArch() == llvm::Triple::aarch64)
+  else if (ToolChain.getArch() == llvm::Triple::aarch64 ||
+           ToolChain.getArch() == llvm::Triple::arm64)
     return "/lib/ld-linux-aarch64.so.1";
   else if (ToolChain.getArch() == llvm::Triple::aarch64_be)
     return "/lib/ld-linux-aarch64_be.so.1";
@@ -6811,7 +6872,8 @@ void gnutools::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)
+  else if (ToolChain.getArch() == llvm::Triple::aarch64 ||
+           ToolChain.getArch() == llvm::Triple::arm64)
     CmdArgs.push_back("aarch64linux");
   else if (ToolChain.getArch() == llvm::Triple::aarch64_be)
     CmdArgs.push_back("aarch64_be_linux");