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authorShih-wei Liao <sliao@google.com>2010-02-10 11:10:31 -0800
committerShih-wei Liao <sliao@google.com>2010-02-10 11:10:31 -0800
commite264f62ca09a8f65c87a46d562a4d0f9ec5d457e (patch)
tree59e3d57ef656cef79afa708ae0a3daf25cd91fcf /test/Transforms/LoopDeletion/dcetest.ll
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Check in LLVM r95781.
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diff --git a/test/Transforms/LoopDeletion/dcetest.ll b/test/Transforms/LoopDeletion/dcetest.ll
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+; This is the test case taken from Appel's book that illustrates a hard case
+; that SCCP gets right, and when followed by ADCE, is completely eliminated
+;
+; RUN: opt < %s -sccp -simplifycfg -indvars -loop-deletion -dce -simplifycfg -S | not grep br
+
+define i32 @"test function"(i32 %i0, i32 %j0) {
+BB1:
+ br label %BB2
+
+BB2: ; preds = %BB7, %BB1
+ %j2 = phi i32 [ %j4, %BB7 ], [ 1, %BB1 ] ; <i32> [#uses=2]
+ %k2 = phi i32 [ %k4, %BB7 ], [ 0, %BB1 ] ; <i32> [#uses=4]
+ %kcond = icmp slt i32 %k2, 100 ; <i1> [#uses=1]
+ br i1 %kcond, label %BB3, label %BB4
+
+BB3: ; preds = %BB2
+ %jcond = icmp slt i32 %j2, 20 ; <i1> [#uses=1]
+ br i1 %jcond, label %BB5, label %BB6
+
+BB4: ; preds = %BB2
+ ret i32 %j2
+
+BB5: ; preds = %BB3
+ %k3 = add i32 %k2, 1 ; <i32> [#uses=1]
+ br label %BB7
+
+BB6: ; preds = %BB3
+ %k5 = add i32 %k2, 1 ; <i32> [#uses=1]
+ br label %BB7
+
+BB7: ; preds = %BB6, %BB5
+ %j4 = phi i32 [ 1, %BB5 ], [ %k2, %BB6 ] ; <i32> [#uses=1]
+ %k4 = phi i32 [ %k3, %BB5 ], [ %k5, %BB6 ] ; <i32> [#uses=1]
+ br label %BB2
+}
+