Add tests for .seh_setframe and .seh_handlerdata parsing. Fix issues with

them.

I had to add a special SwitchSectionNoChange method to MCStreamer just for
.seh_handlerdata. If this isn't OK, please let me know, and I'll find some
other way to fix .seh_handlerdata streaming.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132084 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/MC/MCStreamer.h

@@ -195,6 +195,17 @@ namespace llvm {
       }
     }
 
+    /// SwitchSectionNoChange - Set the current section where code is being
+    /// emitted to @p Section.  This is required to update CurSection. This
+    /// version does not call ChangeSection.
+    void SwitchSectionNoChange(const MCSection *Section) {
+      assert(Section && "Cannot switch to a null section!");
+      const MCSection *curSection = SectionStack.back().first;
+      SectionStack.back().second = curSection;
+      if (Section != curSection)
+        SectionStack.back().first = Section;
+    }
+
     /// InitSections - Create the default sections and set the initial one.
     virtual void InitSections() = 0;