1 files changed, 38 insertions, 0 deletions
diff --git a/test/Transforms/InstCombine/trunc-mask-ext.ll b/test/Transforms/InstCombine/trunc-mask-ext.ll
new file mode 100644
index 000000000000..7e3d8446acff
--- /dev/null
+++ b/test/Transforms/InstCombine/trunc-mask-ext.ll
@@ -0,0 +1,38 @@
+; RUN: llvm-as < %s | opt -instcombine | llvm-dis > %t
+; RUN: not grep zext %t
+; RUN: not grep sext %t
+
+; Instcombine should be able to eliminate all of these ext casts.
+
+declare void @use(i32)
+
+define i64 @foo(i64 %a) {
+  %b = trunc i64 %a to i32
+  %c = and i32 %b, 15
+  %d = zext i32 %c to i64
+  call void @use(i32 %b)
+  ret i64 %d
+}
+define i64 @bar(i64 %a) {
+  %b = trunc i64 %a to i32
+  %c = shl i32 %b, 4
+  %q = ashr i32 %c, 4
+  %d = sext i32 %q to i64
+  call void @use(i32 %b)
+  ret i64 %d
+}
+define i64 @goo(i64 %a) {
+  %b = trunc i64 %a to i32
+  %c = and i32 %b, 8
+  %d = zext i32 %c to i64
+  call void @use(i32 %b)
+  ret i64 %d
+}
+define i64 @hoo(i64 %a) {
+  %b = trunc i64 %a to i32
+  %c = and i32 %b, 8
+  %x = xor i32 %c, 8
+  %d = zext i32 %x to i64
+  call void @use(i32 %b)
+  ret i64 %d
+}