[RISCV] Add the RISCV target and compiler driver

As RV64 codegen has not yet been upstreamed into LLVM, we focus on RV32 driver 
support (RV64 to follow).

Differential Revision: https://reviews.llvm.org/D39963

llvm-svn: 322276

1 files changed, 23 insertions, 0 deletions

diff --git a/clang/lib/Driver/ToolChains/Linux.cpp b/clang/lib/Driver/ToolChains/Linux.cpp
index 1301cdf114a..9ce2407d991 100644
--- a/clang/lib/Driver/ToolChains/Linux.cpp
+++ b/clang/lib/Driver/ToolChains/Linux.cpp
@@ -11,6 +11,7 @@
 #include "Arch/ARM.h"
 #include "Arch/Mips.h"
 #include "Arch/PPC.h"
+#include "Arch/RISCV.h"
 #include "CommonArgs.h"
 #include "clang/Basic/VirtualFileSystem.h"
 #include "clang/Config/config.h"
@@ -176,6 +177,9 @@ static StringRef getOSLibDir(const llvm::Triple &Triple, const ArgList &Args) {
       Triple.getEnvironment() == llvm::Triple::GNUX32)
     return "libx32";
 
+  if (Triple.getArch() == llvm::Triple::riscv32)
+    return "lib32";
+
   return Triple.isArch32Bit() ? "lib" : "lib64";
 }
 
@@ -226,6 +230,8 @@ Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
   const bool IsAndroid = Triple.isAndroid();
   const bool IsMips = tools::isMipsArch(Arch);
   const bool IsHexagon = Arch == llvm::Triple::hexagon;
+  const bool IsRISCV =
+      Arch == llvm::Triple::riscv32 || Arch == llvm::Triple::riscv64;
 
   if (IsMips && !SysRoot.empty())
     ExtraOpts.push_back("--sysroot=" + SysRoot);
@@ -333,6 +339,11 @@ Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
   addPathIfExists(D, SysRoot + "/lib/../" + OSLibDir, Paths);
   addPathIfExists(D, SysRoot + "/usr/lib/" + MultiarchTriple, Paths);
   addPathIfExists(D, SysRoot + "/usr/lib/../" + OSLibDir, Paths);
+  if (IsRISCV) {
+    StringRef ABIName = tools::riscv::getRISCVABI(Args, Triple);
+    addPathIfExists(D, SysRoot + "/" + OSLibDir + "/" + ABIName, Paths);
+    addPathIfExists(D, SysRoot + "/usr/" + OSLibDir + "/" + ABIName, Paths);
+  }
 
   // Try walking via the GCC triple path in case of biarch or multiarch GCC
   // installations with strange symlinks.
@@ -511,6 +522,18 @@ std::string Linux::getDynamicLinker(const ArgList &Args) const {
     Loader =
         (tools::ppc::hasPPCAbiArg(Args, "elfv1")) ? "ld64.so.1" : "ld64.so.2";
     break;
+  case llvm::Triple::riscv32: {
+    StringRef ABIName = tools::riscv::getRISCVABI(Args, Triple);
+    LibDir = "lib";
+    Loader = ("ld-linux-riscv32-" + ABIName + ".so.1").str();
+    break;
+  }
+  case llvm::Triple::riscv64: {
+    StringRef ABIName = tools::riscv::getRISCVABI(Args, Triple);
+    LibDir = "lib";
+    Loader = ("ld-linux-riscv64-" + ABIName + ".so.1").str();
+    break;
+  }
   case llvm::Triple::sparc:
   case llvm::Triple::sparcel:
     LibDir = "lib";