1; PR23524 2; The test is to check redundency produced by loop unroll pass 3; should be cleaned up by later pass. 4; RUN: opt < %s -O2 -S | FileCheck %s 5 6; After loop unroll: 7; %niter.nsub = add nsw i32 %niter, -1 8; ... 9; %niter.nsub.1 = add nsw i32 %niter.nsub, -1 10; should be merged to: 11; %dec18.1 = add nsw i32 %niter, -2 12; 13; CHECK-LABEL: @_Z3fn1v( 14; CHECK: %niter.nsub.1 = add i32 %niter, -2 15 16; ModuleID = '<stdin>' 17target triple = "x86_64-unknown-linux-gnu" 18 19@b = global i32 0, align 4 20@c = global i32 0, align 4 21 22; Function Attrs: nounwind uwtable 23define void @_Z3fn1v() #0 { 24entry: 25 %tmp = load i32, i32* @b, align 4 26 %tobool20 = icmp eq i32 %tmp, 0 27 br i1 %tobool20, label %for.end6, label %for.body.lr.ph 28 29for.body.lr.ph: ; preds = %entry 30 br label %for.body 31 32for.cond1.for.cond.loopexit_crit_edge: ; preds = %for.inc 33 %add.ptr.lcssa = phi i16* [ %add.ptr, %for.inc ] 34 %incdec.ptr.lcssa = phi i8* [ %incdec.ptr, %for.inc ] 35 br label %for.cond.loopexit 36 37for.cond.loopexit: ; preds = %for.body, %for.cond1.for.cond.loopexit_crit_edge 38 %r.1.lcssa = phi i16* [ %add.ptr.lcssa, %for.cond1.for.cond.loopexit_crit_edge ], [ %r.022, %for.body ] 39 %a.1.lcssa = phi i8* [ %incdec.ptr.lcssa, %for.cond1.for.cond.loopexit_crit_edge ], [ %a.021, %for.body ] 40 %tmp1 = load i32, i32* @b, align 4 41 %tobool = icmp eq i32 %tmp1, 0 42 br i1 %tobool, label %for.cond.for.end6_crit_edge, label %for.body 43 44for.body: ; preds = %for.cond.loopexit, %for.body.lr.ph 45 %r.022 = phi i16* [ undef, %for.body.lr.ph ], [ %r.1.lcssa, %for.cond.loopexit ] 46 %a.021 = phi i8* [ undef, %for.body.lr.ph ], [ %a.1.lcssa, %for.cond.loopexit ] 47 %tmp2 = load i32, i32* @c, align 4 48 %tobool215 = icmp eq i32 %tmp2, 0 49 br i1 %tobool215, label %for.cond.loopexit, label %for.body3.lr.ph 50 51for.body3.lr.ph: ; preds = %for.body 52 br label %for.body3 53 54for.body3: ; preds = %for.inc, %for.body3.lr.ph 55 %dec18.in = phi i32 [ %tmp2, %for.body3.lr.ph ], [ %dec18, %for.inc ] 56 %r.117 = phi i16* [ %r.022, %for.body3.lr.ph ], [ %add.ptr, %for.inc ] 57 %a.116 = phi i8* [ %a.021, %for.body3.lr.ph ], [ %incdec.ptr, %for.inc ] 58 %dec18 = add nsw i32 %dec18.in, -1 59 %tmp3 = load i8, i8* %a.116, align 1 60 %cmp = icmp eq i8 %tmp3, 0 61 br i1 %cmp, label %if.then, label %for.inc 62 63if.then: ; preds = %for.body3 64 %arrayidx = getelementptr inbounds i16, i16* %r.117, i64 1 65 store i16 0, i16* %arrayidx, align 2 66 store i16 0, i16* %r.117, align 2 67 %arrayidx5 = getelementptr inbounds i16, i16* %r.117, i64 2 68 store i16 0, i16* %arrayidx5, align 2 69 br label %for.inc 70 71for.inc: ; preds = %if.then, %for.body3 72 %incdec.ptr = getelementptr inbounds i8, i8* %a.116, i64 1 73 %add.ptr = getelementptr inbounds i16, i16* %r.117, i64 3 74 %tobool2 = icmp eq i32 %dec18, 0 75 br i1 %tobool2, label %for.cond1.for.cond.loopexit_crit_edge, label %for.body3, !llvm.loop !0 76 77for.cond.for.end6_crit_edge: ; preds = %for.cond.loopexit 78 br label %for.end6 79 80for.end6: ; preds = %for.cond.for.end6_crit_edge, %entry 81 ret void 82} 83 84!0 = !{!0, !1} 85!1 = !{!"llvm.loop.unroll.count", i32 2} 86