llvm-project/polly/test/DependenceInfo/reduction_only_reduction_like_access.ll

; RUN: opt %loadPolly -polly-dependences -analyze < %s | FileCheck %s
;
; FIXME: Change the comment once we allow different pointers
; The statement is "almost" reduction like but should not yield any reduction dependences
;
; We are limited to binary reductions at the moment and this is not one.
; There are never at least two iterations which read __and__ write to the same
; location, thus we won't find the RAW and WAW dependences of a reduction,
; thus we should not find Reduction dependences.
;
; CHECK:  Reduction dependences:
; CHECK:    {  }
;
; void f(int *sum) {
;   for (int i = 0; i < 100; i++)
;     sum[i] = sum[99-i] + i;
; }
target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-n32-S64"

define void @f(i32* %sum) {
entry:
  br label %for.cond

for.cond:                                         ; preds = %for.inc, %entry
  %i.0 = phi i32 [ 0, %entry ], [ %inc, %for.inc ]
  %exitcond = icmp ne i32 %i.0, 100
  br i1 %exitcond, label %for.body, label %for.end

for.body:                                         ; preds = %for.cond
  %sub = sub nsw i32 99, %i.0
  %arrayidx = getelementptr inbounds i32, i32* %sum, i32 %sub
  %tmp = load i32, i32* %arrayidx, align 4
  %add = add nsw i32 %tmp, %i.0
  %arrayidx1 = getelementptr inbounds i32, i32* %sum, i32 %i.0
  store i32 %add, i32* %arrayidx1, align 4
  br label %for.inc

for.inc:                                          ; preds = %for.body
  %inc = add nsw i32 %i.0, 1
  br label %for.cond

for.end:                                          ; preds = %for.cond
  ret void
}