llvm/test/Transforms/HardwareLoops/ARM/structure.ll

; RUN: opt -mtriple=thumbv8.1m.main-arm-none-eabi -hardware-loops -disable-arm-loloops=false %s -S -o - | FileCheck %s

; CHECK-LABEL: early_exit
; CHECK-NOT: llvm.set.loop.iterations
; CHECK-NOT: llvm.loop.decrement
define i32 @early_exit(i32* nocapture readonly %a, i32 %max, i32 %n) {
entry:
  br label %do.body

do.body:
  %i.0 = phi i32 [ 0, %entry ], [ %inc, %if.end ]
  %arrayidx = getelementptr inbounds i32, i32* %a, i32 %i.0
  %0 = load i32, i32* %arrayidx, align 4
  %cmp = icmp sgt i32 %0, %max
  br i1 %cmp, label %do.end, label %if.end

if.end:
  %inc = add nuw i32 %i.0, 1
  %cmp1 = icmp ult i32 %inc, %n
  br i1 %cmp1, label %do.body, label %if.end.do.end_crit_edge

if.end.do.end_crit_edge:
  %arrayidx2.phi.trans.insert = getelementptr inbounds i32, i32* %a, i32 %inc
  %.pre = load i32, i32* %arrayidx2.phi.trans.insert, align 4
  br label %do.end

do.end:
  %1 = phi i32 [ %.pre, %if.end.do.end_crit_edge ], [ %0, %do.body ]
  ret i32 %1
}

; CHECK-LABEL: nested
; CHECK-NOT: call void @llvm.set.loop.iterations.i32(i32 %N)
; CHECK: br i1 %cmp20, label %while.end7, label %while.cond1.preheader.us

; CHECK: call void @llvm.set.loop.iterations.i32(i32 %N)
; CHECK: br label %while.body3.us

; CHECK: [[REM:%[^ ]+]] = phi i32 [ %N, %while.cond1.preheader.us ], [ [[LOOP_DEC:%[^ ]+]], %while.body3.us ]
; CHECK: [[LOOP_DEC]] = call i32 @llvm.loop.decrement.reg.i32.i32.i32(i32 [[REM]], i32 1)
; CHECK: [[CMP:%[^ ]+]] = icmp ne i32 [[LOOP_DEC]], 0
; CHECK: br i1 [[CMP]], label %while.body3.us, label %while.cond1.while.end_crit_edge.us

; CHECK-NOT: [[LOOP_DEC1:%[^ ]+]] = call i1 @llvm.loop.decrement.i32(i32 1)
; CHECK-NOT: br i1 [[LOOP_DEC1]], label %while.cond1.preheader.us, label %while.end7
define void @nested(i32* nocapture %A, i32 %N) {
entry:
  %cmp20 = icmp eq i32 %N, 0
  br i1 %cmp20, label %while.end7, label %while.cond1.preheader.us

while.cond1.preheader.us:
  %i.021.us = phi i32 [ %inc6.us, %while.cond1.while.end_crit_edge.us ], [ 0, %entry ]
  %mul.us = mul i32 %i.021.us, %N
  br label %while.body3.us

while.body3.us:
  %j.019.us = phi i32 [ 0, %while.cond1.preheader.us ], [ %inc.us, %while.body3.us ]
  %add.us = add i32 %j.019.us, %mul.us
  %arrayidx.us = getelementptr inbounds i32, i32* %A, i32 %add.us
  store i32 %add.us, i32* %arrayidx.us, align 4
  %inc.us = add nuw i32 %j.019.us, 1
  %exitcond = icmp eq i32 %inc.us, %N
  br i1 %exitcond, label %while.cond1.while.end_crit_edge.us, label %while.body3.us

while.cond1.while.end_crit_edge.us:
  %inc6.us = add nuw i32 %i.021.us, 1
  %exitcond23 = icmp eq i32 %inc6.us, %N
  br i1 %exitcond23, label %while.end7, label %while.cond1.preheader.us

while.end7:
  ret void
}