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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: llvm-as < %s | opt -sccp -simplifycfg -indvars -loop-deletion -dce -simplifycfg | llvm-dis | 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
}
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