Compilation for Intel MCU (Part 1/3)

Add -miamcu option which:
  * Sets IAMCU triple
  * Sets IAMCU ABI
  * Enforces static compilation

Differential Revision: http://reviews.llvm.org/D18398

llvm-svn: 266972
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index 91f7306..e1d0ffb 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -2137,6 +2137,13 @@
           << A->getOption().getName() << Value;
     }
   }
+
+  // Set flags to support MCU ABI.
+  if (Args.hasArg(options::OPT_miamcu)) {
+    CmdArgs.push_back("-mfloat-abi");
+    CmdArgs.push_back("soft");
+    CmdArgs.push_back("-mstack-alignment=4");
+  }
 }
 
 void Clang::AddHexagonTargetArgs(const ArgList &Args,