1; RUN: llc < %s -mtriple=armv7-apple-darwin | FileCheck %s 2; PHI elimination shouldn't break backedge. 3 4%struct.list_data_s = type { i16, i16 } 5%struct.list_head = type { %struct.list_head*, %struct.list_data_s* } 6 7define arm_apcscc %struct.list_head* @t1(%struct.list_head* %list) nounwind { 8entry: 9; CHECK-LABEL: t1: 10 %0 = icmp eq %struct.list_head* %list, null 11 br i1 %0, label %bb2, label %bb 12 13bb: 14; CHECK: LBB0_1: 15; CHECK: LBB0_[[LABEL:[0-9]]]: 16; CHECK: bne LBB0_[[LABEL]] 17; CHECK-NOT: b LBB0_[[LABEL]] 18; CHECK: bx lr 19 %list_addr.05 = phi %struct.list_head* [ %2, %bb ], [ %list, %entry ] 20 %next.04 = phi %struct.list_head* [ %list_addr.05, %bb ], [ null, %entry ] 21 %1 = getelementptr inbounds %struct.list_head, %struct.list_head* %list_addr.05, i32 0, i32 0 22 %2 = load %struct.list_head*, %struct.list_head** %1, align 4 23 store %struct.list_head* %next.04, %struct.list_head** %1, align 4 24 %3 = icmp eq %struct.list_head* %2, null 25 br i1 %3, label %bb2, label %bb 26 27bb2: 28 %next.0.lcssa = phi %struct.list_head* [ null, %entry ], [ %list_addr.05, %bb ] 29 ret %struct.list_head* %next.0.lcssa 30} 31 32; Optimize loop entry, eliminate intra loop branches 33define i32 @t2(i32 %passes, i32* nocapture %src, i32 %size) nounwind readonly { 34entry: 35; CHECK-LABEL: t2: 36 %0 = icmp eq i32 %passes, 0 ; <i1> [#uses=1] 37 br i1 %0, label %bb5, label %bb.nph15 38 39bb1: ; preds = %bb2.preheader, %bb1 40; CHECK: LBB1_[[BB3:.]]: @ %bb3 41; CHECK: LBB1_[[PREHDR:.]]: @ %bb2.preheader 42; CHECK: bmi LBB1_[[BB3]] 43 %indvar = phi i32 [ %indvar.next, %bb1 ], [ 0, %bb2.preheader ] ; <i32> [#uses=2] 44 %sum.08 = phi i32 [ %2, %bb1 ], [ %sum.110, %bb2.preheader ] ; <i32> [#uses=1] 45 %tmp17 = sub i32 %i.07, %indvar ; <i32> [#uses=1] 46 %scevgep = getelementptr i32, i32* %src, i32 %tmp17 ; <i32*> [#uses=1] 47 %1 = load i32, i32* %scevgep, align 4 ; <i32> [#uses=1] 48 %2 = add nsw i32 %1, %sum.08 ; <i32> [#uses=2] 49 %indvar.next = add i32 %indvar, 1 ; <i32> [#uses=2] 50 %exitcond = icmp eq i32 %indvar.next, %size ; <i1> [#uses=1] 51 br i1 %exitcond, label %bb3, label %bb1 52 53bb3: ; preds = %bb1, %bb2.preheader 54; CHECK: LBB1_[[BB1:.]]: @ %bb1 55; CHECK: bne LBB1_[[BB1]] 56 %sum.0.lcssa = phi i32 [ %sum.110, %bb2.preheader ], [ %2, %bb1 ] ; <i32> [#uses=2] 57 %3 = add i32 %pass.011, 1 ; <i32> [#uses=2] 58 %exitcond18 = icmp eq i32 %3, %passes ; <i1> [#uses=1] 59 br i1 %exitcond18, label %bb5, label %bb2.preheader 60 61bb.nph15: ; preds = %entry 62 %i.07 = add i32 %size, -1 ; <i32> [#uses=2] 63 %4 = icmp sgt i32 %i.07, -1 ; <i1> [#uses=1] 64 br label %bb2.preheader 65 66bb2.preheader: ; preds = %bb3, %bb.nph15 67 %pass.011 = phi i32 [ 0, %bb.nph15 ], [ %3, %bb3 ] ; <i32> [#uses=1] 68 %sum.110 = phi i32 [ 0, %bb.nph15 ], [ %sum.0.lcssa, %bb3 ] ; <i32> [#uses=2] 69 br i1 %4, label %bb1, label %bb3 70 71bb5: ; preds = %bb3, %entry 72 %sum.1.lcssa = phi i32 [ 0, %entry ], [ %sum.0.lcssa, %bb3 ] ; <i32> [#uses=1] 73 ret i32 %sum.1.lcssa 74} 75