Test case noticed by Sheng that fails because negative values that are

greater than 64-bits don't have the sign bits extended on construction of
the APInt.

llvm-svn: 35178

llvm/test/Assembler/2007-03-19-NegValue.ll

@@ -0,0 +1,7 @@
+; Test whether negative values > 64 bits retain their negativeness.
+; RUN: llvm-as < %s | llvm-dis | grep 'add i65.*, -1'
+
+define i65 @testConsts(i65 %N) {
+  %a = add i65 %N, -1
+  ret i65 %a
+}