loop-simplify-dep.ll 1.2 KB
; RUN: opt -loop-load-elim -S < %s | FileCheck %s

; Make sure we create a preheader if we dont' have one.

target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"

define void @f(i32* noalias nocapture %A, i32* noalias nocapture readonly %B, i64 %N, i1 %C) {
entry:
  br i1 %C, label %for.body, label %for.end

; CHECK: for.body.preheader:
; CHECK-NEXT: %load_initial = load i32, i32* %A
; CHECK-NEXT: br label %for.body

; CHECK: for.body:
for.body:
; CHECK-NEXT: %store_forwarded = phi i32 [ %load_initial, %for.body.preheader ], [ %add, %for.body ]
  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
  %arrayidx = getelementptr inbounds i32, i32* %A, i64 %indvars.iv
  %load = load i32, i32* %arrayidx, align 4
  %arrayidx2 = getelementptr inbounds i32, i32* %B, i64 %indvars.iv
  %load_1 = load i32, i32* %arrayidx2, align 4
; CHECK: %add = add i32 %load_1, %store_forwarded
  %add = add i32 %load_1, %load
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %arrayidx_next = getelementptr inbounds i32, i32* %A, i64 %indvars.iv.next
  store i32 %add, i32* %arrayidx_next, align 4
  %exitcond = icmp eq i64 %indvars.iv.next, %N
  br i1 %exitcond, label %for.end, label %for.body

for.end:
  ret void
}