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; RUN: opt < %s -passes=loop-interchange -cache-line-size=64 \
; RUN: -pass-remarks-output=%t -disable-output
; RUN: FileCheck -input-file %t --check-prefix=PROFIT-CACHE %s
; RUN: opt < %s -passes=loop-interchange -cache-line-size=64 \
; RUN: -pass-remarks-output=%t -disable-output -loop-interchange-profitabilities=vectorize,cache,instorder
; RUN: FileCheck -input-file %t --check-prefix=PROFIT-VEC %s
@A = dso_local global [256 x [256 x float]] zeroinitializer
@B = dso_local global [256 x [256 x float]] zeroinitializer
@C = dso_local global [256 x [256 x float]] zeroinitializer
@D = dso_local global [256 x [256 x float]] zeroinitializer
@E = dso_local global [256 x [256 x float]] zeroinitializer
@F = dso_local global [256 x [256 x float]] zeroinitializer
; Check the behavior of the LoopInterchange cost-model. In the below code,
; exchanging the loops is not profitable in terms of cache, but it is necessary
; to vectorize the innermost loop.
;
; for (int i = 0; i < 256; i++)
; for (int j = 1; j < 256; j++)
; A[j][i] = A[j-1][i] + B[j][i] + C[i][j] + D[i][j] + E[i][j] + F[i][j];
;
; PROFIT-CACHE: --- !Missed
; PROFIT-CACHE-NEXT: Pass: loop-interchange
; PROFIT-CACHE-NEXT: Name: InterchangeNotProfitable
; PROFIT-CACHE-NEXT: Function: f
; PROFIT-CACHE-NEXT: Args:
; PROFIT-CACHE-NEXT: - String: Interchanging loops is not considered to improve cache locality nor vectorization.
; PROFIT-CACHE-NEXT: ...
; PROFIT-VEC: --- !Passed
; PROFIT-VEC-NEXT: Pass: loop-interchange
; PROFIT-VEC-NEXT: Name: Interchanged
; PROFIT-VEC-NEXT: Function: f
; PROFIT-VEC-NEXT: Args:
; PROFIT-VEC-NEXT: - String: Loop interchanged with enclosing loop.
; PROFIT-VEC-NEXT: ...
define void @f() {
entry:
br label %for.i.header
for.i.header:
%i = phi i64 [ 0, %entry ], [ %i.next, %for.i.inc ]
br label %for.j.body
for.j.body:
%j = phi i64 [ 1, %for.i.header ], [ %j.next, %for.j.body ]
%j.dec = add nsw i64 %j, -1
%a.0.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @A, i64 0, i64 %j.dec, i64 %i
%b.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @B, i64 0, i64 %j, i64 %i
%c.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @C, i64 0, i64 %i, i64 %j
%d.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @D, i64 0, i64 %i, i64 %j
%e.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @E, i64 0, i64 %i, i64 %j
%f.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @F, i64 0, i64 %i, i64 %j
%a.0 = load float, ptr %a.0.index, align 4
%b = load float, ptr %b.index, align 4
%c = load float, ptr %c.index, align 4
%d = load float, ptr %d.index, align 4
%e = load float, ptr %e.index, align 4
%f = load float, ptr %f.index, align 4
%add.0 = fadd float %a.0, %b
%add.1 = fadd float %add.0, %c
%add.2 = fadd float %add.1, %d
%add.3 = fadd float %add.2, %e
%add.4 = fadd float %add.3, %f
%a.1.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @A, i64 %j, i64 %i
store float %add.4, ptr %a.1.index, align 4
%j.next = add nuw nsw i64 %j, 1
%cmp.j = icmp eq i64 %j.next, 256
br i1 %cmp.j, label %for.i.inc, label %for.j.body
for.i.inc:
%i.next = add nuw nsw i64 %i, 1
%cmp.i = icmp eq i64 %i.next, 256
br i1 %cmp.i, label %exit, label %for.i.header
exit:
ret void
}
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