1 files changed, 18 insertions, 0 deletions
diff --git a/llvm/test/Transforms/InstCombine/narrow.ll b/llvm/test/Transforms/InstCombine/narrow.ll
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index 00000000000..bff2b88a5db
--- /dev/null
+++ b/llvm/test/Transforms/InstCombine/narrow.ll
@@ -0,0 +1,18 @@
+; This file contains various testcases that check to see that instcombine
+; is narrowing computations when possible.
+
+; RUN: llvm-upgrade < %s | llvm-as | opt -instcombine | llvm-dis | \
+; RUN:    grep 'ret i1 false'
+
+; test1 - Eliminating the casts in this testcase (by narrowing the AND
+; operation) allows instcombine to realize the function always returns false.
+;
+bool %test1(int %A, int %B) {
+        %C1 = setlt int %A, %B
+        %ELIM1 = zext bool %C1 to uint
+        %C2 = setgt int %A, %B
+        %ELIM2 = zext bool %C2 to uint
+        %C3 = and uint %ELIM1, %ELIM2
+        %ELIM3 = trunc uint %C3 to bool
+        ret bool %ELIM3
+}