Reapply "Frontend support for Nios2 target"

Summary:
- Implements TargetInfo class for Nios2 target.
- Enables handling of -march and -mcpu options for Nios2 target.
- Definition of Nios2 builtin functions.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D33356

Author: belickim <mateusz.belicki@intel.com>
llvm-svn: 306383

1 files changed, 19 insertions, 0 deletions

diff --git a/clang/lib/Driver/ToolChains/CommonArgs.cpp b/clang/lib/Driver/ToolChains/CommonArgs.cpp
index 5e360f62e21..1991b2ecd8f 100644
--- a/clang/lib/Driver/ToolChains/CommonArgs.cpp
+++ b/clang/lib/Driver/ToolChains/CommonArgs.cpp
@@ -215,6 +215,21 @@ static std::string getR600TargetGPU(const ArgList &Args) {
   return "";
 }
 
+static std::string getNios2TargetCPU(const ArgList &Args) {
+  Arg *A = Args.getLastArg(options::OPT_mcpu_EQ);
+  if (!A)
+    A = Args.getLastArg(options::OPT_march_EQ);
+
+  if (!A)
+    return "";
+
+  const char *name = A->getValue();
+  return llvm::StringSwitch<const char *>(name)
+      .Case("r1", "nios2r1")
+      .Case("r2", "nios2r2")
+      .Default(name);
+}
+
 static std::string getLanaiTargetCPU(const ArgList &Args) {
   if (Arg *A = Args.getLastArg(options::OPT_mcpu_EQ)) {
     return A->getValue();
@@ -267,6 +282,10 @@ std::string tools::getCPUName(const ArgList &Args, const llvm::Triple &T,
       return A->getValue();
     return "";
 
+  case llvm::Triple::nios2: {
+    return getNios2TargetCPU(Args);
+  }
+
   case llvm::Triple::mips:
   case llvm::Triple::mipsel:
   case llvm::Triple::mips64: