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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118337 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/README.txt b/lib/Target/README.txt
index e63df536ae076c78a1288a77606060f68a50b74a..55c08173d200ba2fe67ddd372bb8c64fd463e441 100644 (file)
--- a/lib/Target/README.txt
+++ b/lib/Target/README.txt
@@ -1963,3 +1963,15 @@ bb3:            ; preds = %entry
         ret i32 %b
 }
 //===---------------------------------------------------------------------===//
+We should fold this code into "ret i1 false" since neither %zero nor %one can
+ever be null pointers.
+
+define i1 @foo(i1 %cond) {
+  %zero = alloca i32
+  %one = alloca i32
+
+  %ptr = select i1 %cond, i32* %zero, i32* %one
+  %isnull = icmp eq i32* %ptr, null
+  ret i1 %isnull
+}
+//===---------------------------------------------------------------------===//