Note from the llvm-dev list

src/codegen/entry.cpp

@@ -27,6 +27,7 @@
 #include "llvm/IR/Module.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/DynamicLibrary.h"
+#include "llvm/Support/Host.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/TargetSelect.h"
@@ -205,6 +206,9 @@ void initCodegen() {
     // target_options.EnableFastISel = true;
     eb.setTargetOptions(target_options);
 
+    // TODO enable this?  should let us get better code:
+    // eb.setMCPU(llvm::sys::getHostCPUName());
+
     g.tm = eb.selectTarget();
     assert(g.tm && "failed to get a target machine");
     g.engine = eb.create(g.tm);