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; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py UTC_ARGS: --version 5
; RUN: opt -passes="print<access-info>" %s 2>&1 | FileCheck %s
@a = dso_local local_unnamed_addr global [65536 x float] zeroinitializer, align 16
; Generated from the following C code:
; #define LEN 256 * 256
; float a[LEN];
;
; void different_strides() {
; for (int i = 0; i < LEN - 1024 - 255; i++) {
; #pragma clang loop interleave(disable)
; #pragma clang loop unroll(disable)
; for (int j = 0; j < 256; j++)
; a[i + j + 1024] += a[j * 4 + i];
; }
; }
; The load and store have different strides(4 and 16 bytes respectively) but the store
; is always at safe positive distance away from the load, thus BackwardVectorizable
define void @different_strides_backward_vectorizable() {
; CHECK-LABEL: 'different_strides_backward_vectorizable'
; CHECK-NEXT: inner.body:
; CHECK-NEXT: Memory dependences are safe
; CHECK-NEXT: Dependences:
; CHECK-NEXT: Forward:
; CHECK-NEXT: %5 = load float, ptr %arrayidx8, align 4 ->
; CHECK-NEXT: store float %add9, ptr %arrayidx8, align 4
; CHECK-EMPTY:
; CHECK-NEXT: Run-time memory checks:
; CHECK-NEXT: Grouped accesses:
; CHECK-EMPTY:
; CHECK-NEXT: Non vectorizable stores to invariant address were not found in loop.
; CHECK-NEXT: SCEV assumptions:
; CHECK-EMPTY:
; CHECK-NEXT: Expressions re-written:
; CHECK-NEXT: outer.header:
; CHECK-NEXT: Report: loop is not the innermost loop
; CHECK-NEXT: Dependences:
; CHECK-NEXT: Run-time memory checks:
; CHECK-NEXT: Grouped accesses:
; CHECK-EMPTY:
; CHECK-NEXT: Non vectorizable stores to invariant address were not found in loop.
; CHECK-NEXT: SCEV assumptions:
; CHECK-EMPTY:
; CHECK-NEXT: Expressions re-written:
;
entry:
br label %outer.header
outer.header:
%i = phi i64 [ 0, %entry ], [ %i.next, %outer.latch ]
%0 = add nuw nsw i64 %i, 1024
br label %inner.body
inner.body:
%j = phi i64 [ 0, %outer.header ], [ %j.next, %inner.body ]
%1 = shl nuw nsw i64 %j, 2
%2 = add nuw nsw i64 %1, %i
%arrayidx = getelementptr inbounds [65536 x float], ptr @a, i64 0, i64 %2
%3 = load float, ptr %arrayidx, align 4
%4 = add nuw nsw i64 %0, %j
%arrayidx8 = getelementptr inbounds [65536 x float], ptr @a, i64 0, i64 %4
%5 = load float, ptr %arrayidx8, align 4
%add9 = fadd fast float %5, %3
store float %add9, ptr %arrayidx8, align 4
%j.next = add nuw nsw i64 %j, 1
%exitcond.not = icmp eq i64 %j.next, 256
br i1 %exitcond.not, label %outer.latch, label %inner.body
outer.latch:
%i.next = add nuw nsw i64 %i, 1
%outerexitcond.not = icmp eq i64 %i.next, 64257
br i1 %outerexitcond.not, label %exit, label %outer.header
exit:
ret void
}
; Generated from following C code:
; void different_stride_and_not_vectorizable(){
; for(int i = 0; i < LEN2; i++){
; for(int j = 0 ; j < LEN; j++){
; a[i + j + LEN] += a[i + 4*j];
; }
; }
; }
; The load and store have different strides, but the store and load are not at a
; safe distance away from each other, thus not safe for vectorization.
define void @different_stride_and_not_vectorizable() {
; CHECK-LABEL: 'different_stride_and_not_vectorizable'
; CHECK-NEXT: inner.body:
; CHECK-NEXT: Report: unsafe dependent memory operations in loop. Use #pragma clang loop distribute(enable) to allow loop distribution to attempt to isolate the offending operations into a separate loop
; CHECK-NEXT: Unknown data dependence.
; CHECK-NEXT: Dependences:
; CHECK-NEXT: Unknown:
; CHECK-NEXT: %3 = load float, ptr %arrayidx, align 4 ->
; CHECK-NEXT: store float %add9, ptr %arrayidx8, align 4
; CHECK-EMPTY:
; CHECK-NEXT: Forward:
; CHECK-NEXT: %5 = load float, ptr %arrayidx8, align 4 ->
; CHECK-NEXT: store float %add9, ptr %arrayidx8, align 4
; CHECK-EMPTY:
; CHECK-NEXT: Run-time memory checks:
; CHECK-NEXT: Grouped accesses:
; CHECK-EMPTY:
; CHECK-NEXT: Non vectorizable stores to invariant address were not found in loop.
; CHECK-NEXT: SCEV assumptions:
; CHECK-EMPTY:
; CHECK-NEXT: Expressions re-written:
; CHECK-NEXT: outer.header:
; CHECK-NEXT: Report: loop is not the innermost loop
; CHECK-NEXT: Dependences:
; CHECK-NEXT: Run-time memory checks:
; CHECK-NEXT: Grouped accesses:
; CHECK-EMPTY:
; CHECK-NEXT: Non vectorizable stores to invariant address were not found in loop.
; CHECK-NEXT: SCEV assumptions:
; CHECK-EMPTY:
; CHECK-NEXT: Expressions re-written:
;
entry:
br label %outer.header
outer.header:
%i = phi i64 [ 0, %entry ], [ %i.next, %outer.latch ]
%0 = add nuw nsw i64 %i, 256
br label %inner.body
inner.body:
%j = phi i64 [ 0, %outer.header ], [ %j.next, %inner.body ]
%1 = shl nuw nsw i64 %j, 2
%2 = add nuw nsw i64 %1, %i
%arrayidx = getelementptr inbounds [65536 x float], ptr @a, i64 0, i64 %2
%3 = load float, ptr %arrayidx, align 4
%4 = add nuw nsw i64 %0, %j
%arrayidx8 = getelementptr inbounds [65536 x float], ptr @a, i64 0, i64 %4
%5 = load float, ptr %arrayidx8, align 4
%add9 = fadd fast float %5, %3
store float %add9, ptr %arrayidx8, align 4
%j.next = add nuw nsw i64 %j, 1
%exitcond.not = icmp eq i64 %j.next, 256
br i1 %exitcond.not, label %outer.latch, label %inner.body
outer.latch:
%i.next = add nuw nsw i64 %i, 1
%exitcond29.not = icmp eq i64 %i.next, 65536
br i1 %exitcond29.not, label %exit, label %outer.header
exit:
ret void
}
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