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1; RUN: opt -S -passes='loop(indvars),loop-vectorize' -force-vector-width=2 < %s | FileCheck %s2 3target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:32:32-n8:16:32-S128"4 5@a = common global i64 0, align 86@x = common global i32 0, align 47 8; We used to assert on this loop because we could not find an induction9; variable but assumed there must be one. Scalar evolution returned a exit10; count for the loop below and from there on we assumed that there must be an11; induction variable. This is not a valid assumption:12; // getExitCount - Get the expression for the number of loop iterations for13; // which this loop is *guaranteed not to exit* via ExitingBlock. Otherwise14; // return SCEVCouldNotCompute.15; For an infinite loop SE can return any number.16 17; CHECK-LABEL: @fn1(18define void @fn1() {19entry:20 store i64 0, ptr @a, align 821 br label %for.body22 23for.body: ; preds = %for.body, %entry24 %inc1 = phi i64 [ 0, %entry ], [ %inc, %for.body ]25 store volatile i32 0, ptr @x, align 426 %inc = add nsw i64 %inc1, 127 %cmp = icmp sgt i64 %inc1, -228 br i1 %cmp, label %for.body, label %for.end29 30for.end: ; preds = %for.body31 %inc.lcssa = phi i64 [ %inc, %for.body ]32 store i64 %inc.lcssa, ptr @a, align 833 ret void34}35