xref: /llvm-project/llvm/test/Transforms/LoopLoadElim/opt-size.ll (revision 055fb7795aa219a3d274d280ec9129784f169f56)

; RUN: opt -passes=loop-load-elim -S < %s | FileCheck %s
; RUN: opt -aa-pipeline=basic-aa -passes='require<profile-summary>,function(loop-load-elim)' -S < %s | FileCheck %s -check-prefix=PGSO
; RUN: opt -passes=loop-load-elim -pgso=false -S < %s | FileCheck %s -check-prefix=NPGSO

; When optimizing for size don't eliminate in this loop because the loop would
; have to be versioned first because A and C may alias.
;
;   for (unsigned i = 0; i < 100; i++) {
;     A[i+1] = B[i] + 2;
;     C[i] = A[i] * 2;
;   }

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

; CHECK-LABEL: @f(
define void @f(ptr %A, ptr %B, ptr %C, i64 %N) optsize {

entry:
  br label %for.body

for.body:                                         ; preds = %for.body, %entry
  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1

  %Aidx_next = getelementptr inbounds i32, ptr %A, i64 %indvars.iv.next
  %Bidx = getelementptr inbounds i32, ptr %B, i64 %indvars.iv
  %Cidx = getelementptr inbounds i32, ptr %C, i64 %indvars.iv
  %Aidx = getelementptr inbounds i32, ptr %A, i64 %indvars.iv

  %b = load i32, ptr %Bidx, align 4
  %a_p1 = add i32 %b, 2
  store i32 %a_p1, ptr %Aidx_next, align 4

  %a = load i32, ptr %Aidx, align 4
; CHECK: %c = mul i32 %a, 2
  %c = mul i32 %a, 2
  store i32 %c, ptr %Cidx, align 4

  %exitcond = icmp eq i64 %indvars.iv.next, %N
  br i1 %exitcond, label %for.end, label %for.body

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

; Same loop but with noalias on %A and %C.  In this case load-eliminate even
; with -Os.

; CHECK-LABEL: @g(
define void @g(ptr noalias %A, ptr %B, ptr noalias %C, i64 %N) optsize {

entry:
  br label %for.body

for.body:                                         ; preds = %for.body, %entry
  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1

  %Aidx_next = getelementptr inbounds i32, ptr %A, i64 %indvars.iv.next
  %Bidx = getelementptr inbounds i32, ptr %B, i64 %indvars.iv
  %Cidx = getelementptr inbounds i32, ptr %C, i64 %indvars.iv
  %Aidx = getelementptr inbounds i32, ptr %A, i64 %indvars.iv

  %b = load i32, ptr %Bidx, align 4
  %a_p1 = add i32 %b, 2
  store i32 %a_p1, ptr %Aidx_next, align 4

  %a = load i32, ptr %Aidx, align 4
; CHECK: %c = mul i32 %store_forwarded, 2
  %c = mul i32 %a, 2
  store i32 %c, ptr %Cidx, align 4

  %exitcond = icmp eq i64 %indvars.iv.next, %N
  br i1 %exitcond, label %for.end, label %for.body

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


; PGSO-LABEL: @f_pgso(
; NPGSO-LABEL: @f_pgso(
define void @f_pgso(ptr %A, ptr %B, ptr %C, i64 %N) !prof !14 {

entry:
  br label %for.body

for.body:                                         ; preds = %for.body, %entry
  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1

  %Aidx_next = getelementptr inbounds i32, ptr %A, i64 %indvars.iv.next
  %Bidx = getelementptr inbounds i32, ptr %B, i64 %indvars.iv
  %Cidx = getelementptr inbounds i32, ptr %C, i64 %indvars.iv
  %Aidx = getelementptr inbounds i32, ptr %A, i64 %indvars.iv

  %b = load i32, ptr %Bidx, align 4
  %a_p1 = add i32 %b, 2
  store i32 %a_p1, ptr %Aidx_next, align 4

  %a = load i32, ptr %Aidx, align 4
; PGSO: %c = mul i32 %a, 2
; NPGSO-NOT: %c = mul i32 %a, 2
  %c = mul i32 %a, 2
  store i32 %c, ptr %Cidx, align 4

  %exitcond = icmp eq i64 %indvars.iv.next, %N
  br i1 %exitcond, label %for.end, label %for.body

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

!llvm.module.flags = !{!0}
!0 = !{i32 1, !"ProfileSummary", !1}
!1 = !{!2, !3, !4, !5, !6, !7, !8, !9}
!2 = !{!"ProfileFormat", !"InstrProf"}
!3 = !{!"TotalCount", i64 10000}
!4 = !{!"MaxCount", i64 10}
!5 = !{!"MaxInternalCount", i64 1}
!6 = !{!"MaxFunctionCount", i64 1000}
!7 = !{!"NumCounts", i64 3}
!8 = !{!"NumFunctions", i64 3}
!9 = !{!"DetailedSummary", !10}
!10 = !{!11, !12, !13}
!11 = !{i32 10000, i64 100, i32 1}
!12 = !{i32 999000, i64 100, i32 1}
!13 = !{i32 999999, i64 1, i32 2}
!14 = !{!"function_entry_count", i64 0}