1 ; RUN: opt -S -indvars -loop-vectorize -force-vector-width=2 < %s | FileCheck %s 2 3 target 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 8 6 @x = common global i32 0, align 4 7 8 ; We used to assert on this loop because we could not find an induction 9 ; variable but assumed there must be one. Scalar evolution returned a exit 10 ; count for the loop below and from there on we assumed that there must be an 11 ; induction variable. This is not a valid assumption: 12 ; // getExitCount - Get the expression for the number of loop iterations for 13 ; // which this loop is *guaranteed not to exit* via ExitingBlock. Otherwise 14 ; // return SCEVCouldNotCompute. 15 ; For an infinite loop SE can return any number. 16 17 ; CHECK-LABEL: @fn1( 18 define void @fn1() { 19 entry: 20 store i64 0, i64* @a, align 8 21 br label %for.body 22 23 for.body: ; preds = %for.body, %entry 24 %inc1 = phi i64 [ 0, %entry ], [ %inc, %for.body ] 25 store volatile i32 0, i32* @x, align 4 26 %inc = add nsw i64 %inc1, 1 27 %cmp = icmp sgt i64 %inc1, -2 28 br i1 %cmp, label %for.body, label %for.end 29 30 for.end: ; preds = %for.body 31 %inc.lcssa = phi i64 [ %inc, %for.body ] 32 store i64 %inc.lcssa, i64* @a, align 8 33 ret void 34 } 35
