1 ; RUN: opt < %s -S -indvars | grep {= icmp} | count 3 2 ; PR4914.ll 3 4 ; Indvars should be able to do range analysis and eliminate icmps. 5 ; There are two here which cannot be eliminated. 6 ; There's one that icmp which can be eliminated and which indvars currently 7 ; cannot eliminate, because it requires analyzing more than just the 8 ; range of the induction variable. 9 10 @0 = private constant [4 x i8] c"%d\0A\00", align 1 ; <[4 x i8]*> [#uses=1] 11 12 define i32 @main() nounwind { 13 bb: 14 br label %bb1 15 16 bb1: ; preds = %bb14, %bb 17 %t = phi i32 [ 0, %bb ], [ %t19, %bb14 ] ; <i32> [#uses=5] 18 %t2 = phi i32 [ 0, %bb ], [ %t18, %bb14 ] ; <i32> [#uses=1] 19 %t3 = icmp slt i32 %t, 0 ; <i1> [#uses=1] 20 br i1 %t3, label %bb7, label %bb4 21 22 bb4: ; preds = %bb1 23 %t5 = icmp sgt i32 %t, 255 ; <i1> [#uses=1] 24 %t6 = select i1 %t5, i32 255, i32 %t ; <i32> [#uses=1] 25 br label %bb7 26 27 bb7: ; preds = %bb4, %bb1 28 %t8 = phi i32 [ %t6, %bb4 ], [ 0, %bb1 ] ; <i32> [#uses=1] 29 %t9 = sub i32 0, %t ; <i32> [#uses=3] 30 %t10 = icmp slt i32 %t9, 0 ; <i1> [#uses=1] 31 br i1 %t10, label %bb14, label %bb11 32 33 bb11: ; preds = %bb7 34 %t12 = icmp sgt i32 %t9, 255 ; <i1> [#uses=1] 35 %t13 = select i1 %t12, i32 255, i32 %t9 ; <i32> [#uses=1] 36 br label %bb14 37 38 bb14: ; preds = %bb11, %bb7 39 %t15 = phi i32 [ %t13, %bb11 ], [ 0, %bb7 ] ; <i32> [#uses=1] 40 %t16 = add nsw i32 %t2, 255 ; <i32> [#uses=1] 41 %t17 = add nsw i32 %t16, %t8 ; <i32> [#uses=1] 42 %t18 = add nsw i32 %t17, %t15 ; <i32> [#uses=2] 43 %t19 = add nsw i32 %t, 1 ; <i32> [#uses=2] 44 %t20 = icmp slt i32 %t19, 1000000000 ; <i1> [#uses=1] 45 br i1 %t20, label %bb1, label %bb21 46 47 bb21: ; preds = %bb14 48 %t22 = call i32 (i8*, ...)* @printf(i8* noalias getelementptr inbounds ([4 x i8]* @0, i32 0, i32 0), i32 %t18) nounwind 49 ret i32 0 50 } 51 52 declare i32 @printf(i8* noalias nocapture, ...) nounwind 53
