Turn on mips16 pseudo op when compiling for mips16.
Expand test case for this.

Patch by Reed Kotler.

llvm-svn: 157410
diff --git a/llvm/lib/Target/Mips/MipsAsmPrinter.cpp b/llvm/lib/Target/Mips/MipsAsmPrinter.cpp
index d62df4d..dfeae9a 100644
--- a/llvm/lib/Target/Mips/MipsAsmPrinter.cpp
+++ b/llvm/lib/Target/Mips/MipsAsmPrinter.cpp
@@ -274,8 +274,14 @@
 }
 
 void MipsAsmPrinter::EmitFunctionEntryLabel() {
-  if (OutStreamer.hasRawTextSupport())
+  if (OutStreamer.hasRawTextSupport()) {
+    if (Subtarget->inMips16Mode())
+      OutStreamer.EmitRawText(StringRef("\t.set\tmips16"));
+    else
+      OutStreamer.EmitRawText(StringRef("\t.set\tnomips16"));
+    OutStreamer.EmitRawText(StringRef("\t.set\tnomicromips"));
     OutStreamer.EmitRawText("\t.ent\t" + Twine(CurrentFnSym->getName()));
+  }
   OutStreamer.EmitLabel(CurrentFnSym);
 }
 
diff --git a/llvm/test/CodeGen/Mips/null.ll b/llvm/test/CodeGen/Mips/null.ll
index a5e2c06..f34f6a4 100644
--- a/llvm/test/CodeGen/Mips/null.ll
+++ b/llvm/test/CodeGen/Mips/null.ll
@@ -5,6 +5,9 @@
 entry:
   ret i32 0
 
+; 16: 	.set	mips16                  # @main
+; 16:	.set	nomicromips
+
 ; 16:	jr	$ra
 
 }