llvm/llvm/test/CodeGen/ARM/code-placement.ll

; RUN: llc < %s -mtriple=armv7-apple-darwin | FileCheck %s
; PHI elimination shouldn't break backedge.

%struct.list_data_s = type { i16, i16 }
%struct.list_head = type { ptr, ptr }

define arm_apcscc ptr @t1(ptr %list) nounwind {
entry:
; CHECK-LABEL: t1:
  %0 = icmp eq ptr %list, null
  br i1 %0, label %bb2, label %bb

bb:
; CHECK: LBB0_[[LABEL:[0-9]]]:
; CHECK: bne LBB0_[[LABEL]]
; CHECK-NOT: b LBB0_[[LABEL]]
; CHECK: bx lr
  %list_addr.05 = phi ptr [ %2, %bb ], [ %list, %entry ]
  %next.04 = phi ptr [ %list_addr.05, %bb ], [ null, %entry ]
  %1 = getelementptr inbounds %struct.list_head, ptr %list_addr.05, i32 0, i32 0
  %2 = load ptr, ptr %1, align 4
  store ptr %next.04, ptr %1, align 4
  %3 = icmp eq ptr %2, null
  br i1 %3, label %bb2, label %bb

bb2:
  %next.0.lcssa = phi ptr [ null, %entry ], [ %list_addr.05, %bb ]
  ret ptr %next.0.lcssa
}

; Optimize loop entry, eliminate intra loop branches
define i32 @t2(i32 %passes, ptr nocapture %src, i32 %size) nounwind readonly {
entry:
; CHECK-LABEL: t2:
  %0 = icmp eq i32 %passes, 0                     ; <i1> [#uses=1]
  br i1 %0, label %bb5, label %bb.nph15

bb1:                                              ; preds = %bb2.preheader, %bb1
; CHECK: LBB1_[[BB3:.]]: @ %bb3
; CHECK: LBB1_[[PREHDR:.]]: @ %bb2.preheader
; CHECK: bmi LBB1_[[BB3]]
  %indvar = phi i32 [ %indvar.next, %bb1 ], [ 0, %bb2.preheader ] ; <i32> [#uses=2]
  %sum.08 = phi i32 [ %2, %bb1 ], [ %sum.110, %bb2.preheader ] ; <i32> [#uses=1]
  %tmp17 = sub i32 %i.07, %indvar                 ; <i32> [#uses=1]
  %scevgep = getelementptr i32, ptr %src, i32 %tmp17  ; <i32*> [#uses=1]
  %1 = load i32, ptr %scevgep, align 4                ; <i32> [#uses=1]
  %2 = add nsw i32 %1, %sum.08                    ; <i32> [#uses=2]
  %indvar.next = add i32 %indvar, 1               ; <i32> [#uses=2]
  %exitcond = icmp eq i32 %indvar.next, %size     ; <i1> [#uses=1]
  br i1 %exitcond, label %bb3, label %bb1

bb3:                                              ; preds = %bb1, %bb2.preheader
; CHECK: LBB1_[[BB1:.]]: @ %bb1
; CHECK: bne LBB1_[[BB1]]
  %sum.0.lcssa = phi i32 [ %sum.110, %bb2.preheader ], [ %2, %bb1 ] ; <i32> [#uses=2]
  %3 = add i32 %pass.011, 1                       ; <i32> [#uses=2]
  %exitcond18 = icmp eq i32 %3, %passes           ; <i1> [#uses=1]
  br i1 %exitcond18, label %bb5, label %bb2.preheader

bb.nph15:                                         ; preds = %entry
  %i.07 = add i32 %size, -1                       ; <i32> [#uses=2]
  %4 = icmp sgt i32 %i.07, -1                     ; <i1> [#uses=1]
  br label %bb2.preheader

bb2.preheader:                                    ; preds = %bb3, %bb.nph15
  %pass.011 = phi i32 [ 0, %bb.nph15 ], [ %3, %bb3 ] ; <i32> [#uses=1]
  %sum.110 = phi i32 [ 0, %bb.nph15 ], [ %sum.0.lcssa, %bb3 ] ; <i32> [#uses=2]
  br i1 %4, label %bb1, label %bb3

bb5:                                              ; preds = %bb3, %entry
  %sum.1.lcssa = phi i32 [ 0, %entry ], [ %sum.0.lcssa, %bb3 ] ; <i32> [#uses=1]
  ret i32 %sum.1.lcssa
}