llvm/polly/test/MaximalStaticExpansion/read_from_original.ll

; RUN: opt %loadNPMPolly "-passes=scop(print<polly-mse>)" -disable-output < %s | FileCheck %s
; RUN: opt %loadNPMPolly "-passes=scop(print<polly-mse>)" -pass-remarks-analysis="polly-mse" -disable-output < %s 2>&1 | FileCheck %s --check-prefix=MSE
;
; Verify that Polly detects problems and does not expand the array
;
; Original source code :
;
; #define Ni 2000
; #define Nj 3000
;
; double mse(double A[Ni], double B[Nj]) {
;   int i;
;   double tmp = 6;
;   for (i = 0; i < Ni; i++) {
;     for (int j = 2; j<Nj; j++) {
;       B[j-1] = j;
;     }
;     A[i] = B[i];
;   }
;   return tmp;
; }
;
; Check that the pass detects the problem of read from original array after expansion.
;
; MSE: The expansion of MemRef_B would lead to a read from the original array.
;
; CHECK-NOT: double MemRef_B2_expanded[2000][3000]; // Element size 8
;
; Check that the  memory accesses are not modified
;
; CHECK-NOT: new: { Stmt_for_body3[i0, i1] -> MemRef_B_Stmt_for_body3_expanded[i0, i1] };
; CHECK-NOT: new: { Stmt_for_end[i0] -> MemRef_B_Stmt_for_body3_expanded
;
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"

define double @mse(ptr %A, ptr %B) {
entry:
  br label %entry.split

entry.split:                                      ; preds = %entry
  br label %for.body

for.body:                                         ; preds = %entry.split, %for.end
  %indvars.iv4 = phi i64 [ 0, %entry.split ], [ %indvars.iv.next5, %for.end ]
  br label %for.body3

for.body3:                                        ; preds = %for.body, %for.body3
  %indvars.iv = phi i64 [ 2, %for.body ], [ %indvars.iv.next, %for.body3 ]
  %0 = trunc i64 %indvars.iv to i32
  %conv = sitofp i32 %0 to double
  %1 = add nsw i64 %indvars.iv, -1
  %arrayidx = getelementptr inbounds double, ptr %B, i64 %1
  store double %conv, ptr %arrayidx, align 8
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %exitcond = icmp ne i64 %indvars.iv.next, 3000
  br i1 %exitcond, label %for.body3, label %for.end

for.end:                                          ; preds = %for.body3
  %arrayidx5 = getelementptr inbounds double, ptr %B, i64 %indvars.iv4
  %2 = load i64, ptr %arrayidx5, align 8
  %arrayidx7 = getelementptr inbounds double, ptr %A, i64 %indvars.iv4
  store i64 %2, ptr %arrayidx7, align 8
  %indvars.iv.next5 = add nuw nsw i64 %indvars.iv4, 1
  %exitcond6 = icmp ne i64 %indvars.iv.next5, 2000
  br i1 %exitcond6, label %for.body, label %for.end10

for.end10:                                        ; preds = %for.end
  ret double 6.000000e+00
}