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|
; RUN: opt < %s -passes=loop-interchange -cache-line-size=64 \
; RUN: -pass-remarks-output=%t -disable-output -loop-interchange-profitabilities=vectorize
; RUN: FileCheck -input-file %t %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 = global [256 x [256 x [256 x float]]] zeroinitializer
@E = global [256 x [256 x [256 x float]]] zeroinitializer
; Check that the below loops are exchanged for vectorization.
;
; for (int i = 0; i < 256; i++) {
; for (int j = 1; j < 256; j++) {
; A[i][j] = A[i][j-1] + B[i][j];
; C[i][j] += 1;
; }
; }
;
; CHECK: --- !Passed
; CHECK-NEXT: Pass: loop-interchange
; CHECK-NEXT: Name: Interchanged
; CHECK-NEXT: Function: interchange_necessary_for_vectorization
; CHECK-NEXT: Args:
; CHECK-NEXT: - String: Loop interchanged with enclosing loop.
define void @interchange_necessary_for_vectorization() {
entry:
br label %for.i.header
for.i.header:
%i = phi i64 [ 1, %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.load.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @A, i64 0, i64 %i, i64 %j.dec
%b.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @B, i64 0, i64 %i, i64 %j
%c.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @C, i64 0, i64 %i, i64 %j
%a = load float, ptr %a.load.index, align 4
%b = load float, ptr %b.index, align 4
%c = load float, ptr %c.index, align 4
%add.0 = fadd float %a, %b
%a.store.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @A, i64 0, i64 %i, i64 %j
store float %add.0, ptr %a.store.index, align 4
%add.1 = fadd float %c, 1.0
store float %add.1, ptr %c.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
}
; Check that the following innermost loop can be vectorized so that
; interchanging is unnecessary.
;
; for (int i = 0; i < 256; i++)
; for (int j = 1; j < 256; j++)
; A[i][j-1] = A[i][j] + B[i][j];
;
; CHECK: --- !Missed
; CHECK-NEXT: Pass: loop-interchange
; CHECK-NEXT: Name: InterchangeNotProfitable
; CHECK-NEXT: Function: interchange_unnecesasry_for_vectorization
; CHECK-NEXT: Args:
; CHECK-NEXT: - String: Insufficient information to calculate the cost of loop for interchange.
define void @interchange_unnecesasry_for_vectorization() {
entry:
br label %for.i.header
for.i.header:
%i = phi i64 [ 1, %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.load.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @A, i64 0, i64 %i, i64 %j
%b.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @B, i64 0, i64 %i, i64 %j
%a = load float, ptr %a.load.index, align 4
%b = load float, ptr %b.index, align 4
%add = fadd float %a, %b
%a.store.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @A, i64 0, i64 %i, i64 %j.dec
store float %add, ptr %a.store.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
}
; Check that the below loops are exchanged to allow innermost loop
; vectorization. We cannot vectorize the j-loop because it has a lexically
; backward dependency, but the i-loop can be vectorized because all the
; loop-carried dependencies are lexically forward. LoopVectorize currently only
; vectorizes innermost loop, hence move the i-loop to that position.
;
; for (int i = 0; i < 255; i++) {
; for (int j = 1; j < 256; j++) {
; A[i][j] = A[i][j-1] + B[i][j];
; C[i][j] += C[i+1][j];
; }
; }
;
; CHECK: --- !Passed
; CHECK-NEXT: Pass: loop-interchange
; CHECK-NEXT: Name: Interchanged
; CHECK-NEXT: Function: interchange_necessary_for_vectorization2
; CHECK-NEXT: Args:
; CHECK-NEXT: - String: Loop interchanged with enclosing loop.
define void @interchange_necessary_for_vectorization2() {
entry:
br label %for.i.header
for.i.header:
%i = phi i64 [ 1, %entry ], [ %i.next, %for.i.inc ]
%i.inc = add i64 %i, 1
br label %for.j.body
for.j.body:
%j = phi i64 [ 1, %for.i.header ], [ %j.next, %for.j.body ]
%j.dec = add i64 %j, -1
%a.load.index = getelementptr [256 x [256 x float]], ptr @A, i64 0, i64 %i, i64 %j.dec
%b.index = getelementptr [256 x [256 x float]], ptr @B, i64 0, i64 %i, i64 %j
%c.load.index = getelementptr [256 x [256 x float]], ptr @C, i64 0, i64 %i.inc, i64 %j
%c.store.index = getelementptr [256 x [256 x float]], ptr @C, i64 0, i64 %i, i64 %j
%a = load float, ptr %a.load.index
%b = load float, ptr %b.index
%c0 = load float, ptr %c.load.index
%c1 = load float, ptr %c.store.index
%add.0 = fadd float %a, %b
%a.store.index = getelementptr [256 x [256 x float]], ptr @A, i64 0, i64 %i, i64 %j
store float %add.0, ptr %a.store.index
%add.1 = fadd float %c0, %c1
store float %add.1, ptr %c.store.index
%j.next = add 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 i64 %i, 1
%cmp.i = icmp eq i64 %i.next, 255
br i1 %cmp.i, label %exit, label %for.i.header
exit:
ret void
}
; Check that no interchange is performed for the following loop. Interchanging
; the j-loop and k-loop makes the innermost loop vectorizble, since the j-loop
; has only forward dependencies. However, at the moment, a loop body consisting
; of multiple BBs is handled pesimistically. Hence the j-loop isn't moved to
; the innermost place.
;
; for (int i = 0; i < 255; i++) {
; for (int j = 0; j < 255; j++) {
; for (int k = 0; k < 128; k++) {
; E[i][j][k] = D[i+1][j+1][2*k];
; if (cond)
; D[i][j][k+1] = 1.0;
; }
; }
; CHECK: --- !Missed
; CHECK-NEXT: Pass: loop-interchange
; CHECK-NEXT: Name: InterchangeNotProfitable
; CHECK-NEXT: Function: multiple_BBs_in_loop
; CHECK-NEXT: Args:
; CHECK-NEXT: - String: Interchanging loops is not considered to improve cache locality nor vectorization.
; CHECK: --- !Missed
; CHECK-NEXT: Pass: loop-interchange
; CHECK-NEXT: Name: InterchangeNotProfitable
; CHECK-NEXT: Function: multiple_BBs_in_loop
; CHECK-NEXT: Args:
; CHECK-NEXT: - String: Interchanging loops is not considered to improve cache locality nor vectorization.
define void @multiple_BBs_in_loop() {
entry:
br label %for.i.header
for.i.header:
%i = phi i64 [ 0, %entry ], [ %i.inc, %for.i.inc ]
%i.inc = add i64 %i, 1
br label %for.j.header
for.j.header:
%j = phi i64 [ 0, %for.i.header ], [ %j.inc, %for.j.inc ]
%j.inc = add i64 %j, 1
br label %for.k.body
for.k.body:
%k = phi i64 [ 0, %for.j.header ], [ %k.inc, %for.k.inc ]
%k.inc = add i64 %k, 1
%k.2 = mul i64 %k, 2
%d.index = getelementptr [256 x [256 x [256 x float]]], ptr @D, i64 0, i64 %i.inc, i64 %j.inc, i64 %k.2
%e.index = getelementptr [256 x [256 x [256 x float]]], ptr @E, i64 0, i64 %i, i64 %j, i64 %k
%d.load = load float, ptr %d.index
store float %d.load, ptr %e.index
%cond = freeze i1 undef
br i1 %cond, label %if.then, label %for.k.inc
if.then:
%d.index2 = getelementptr [256 x [256 x [256 x float]]], ptr @D, i64 0, i64 %i, i64 %j, i64 %k.inc
store float 1.0, ptr %d.index2
br label %for.k.inc
for.k.inc:
%cmp.k = icmp eq i64 %k.inc, 128
br i1 %cmp.k, label %for.j.inc, label %for.k.body
for.j.inc:
%cmp.j = icmp eq i64 %j.inc, 255
br i1 %cmp.j, label %for.i.inc, label %for.j.header
for.i.inc:
%cmp.i = icmp eq i64 %i.inc, 255
br i1 %cmp.i, label %exit, label %for.i.header
exit:
ret void
}
|
