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[DA] Add test cases where base ptr is not loop-invariant #148240

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102 changes: 102 additions & 0 deletions llvm/test/Analysis/DependenceAnalysis/FlipFlopBaseAddress.ll
Original file line number Diff line number Diff line change
Expand Up @@ -157,3 +157,105 @@ for.inc: ; preds = %cond.end5
for.end: ; preds = %for.cond.cleanup
ret void
}

; Pseudo-code for the following IR:
;
; void f(int A[][42]) {
; for (int i = 0; i < 100; i++)
; for (int j = 0; j < 41; j++)
; (j % 2 == 0 ? A[i][j] : A[i][j+1]) = 1;
; }
;
; FIXME: There are loop-carried dependencies between the store instruction. For
; example, the value of %ptr0 when (i, j) = (0, 1) is %A+8, which is the same
; as when (i, j) = (0, 2).

define void @non_invariant_baseptr_with_identical_obj(ptr %A) {
; CHECK-LABEL: 'non_invariant_baseptr_with_identical_obj'
; CHECK-NEXT: Src: store i32 1, ptr %idx, align 4 --> Dst: store i32 1, ptr %idx, align 4
; CHECK-NEXT: da analyze - none!
;
entry:
br label %loop.i.header

loop.i.header:
%i = phi i32 [ 0, %entry ], [ %i.inc, %loop.i.latch ]
%A1 = getelementptr i32, ptr %A, i32 1
br label %loop.j

loop.j:
%j = phi i32 [ 0, %loop.i.header ], [ %j.inc, %loop.j ]
%ptr0 = phi ptr [ %A, %loop.i.header ], [ %ptr1, %loop.j ]
%ptr1 = phi ptr [ %A1, %loop.i.header ], [ %ptr0, %loop.j ]
%idx = getelementptr [42 x i32], ptr %ptr0, i32 %i, i32 %j
store i32 1, ptr %idx
%j.inc = add i32 %j, 1
%cmp.j = icmp slt i32 %j.inc, 41
br i1 %cmp.j, label %loop.j, label %loop.i.latch

loop.i.latch:
%i.inc = add i32 %i, 1
%cmp.i = icmp slt i32 %i.inc, 100
br i1 %cmp.i, label %loop.i.header, label %exit

exit:
ret void
}

; Pseudo-code for the following IR:
;
; void f(int A[][42][42]) {
; for (int i = 0; i < 100; i++)
; for (int j = 0; j < 41; j++) {
; int *ptr0 = (j % 2 == 0 ? A[i][j] : A[i][j+1]);
; for (int k = 0; k < 42; k++)
; ptr0[k] = 1;
; }
; }
;
; Similar to the above case, but ptr0 is loop-invariant with respsect to the
; k-loop.
;
; FIXME: Same as the above case, there are loop-carried dependencies between
; the store.

define void @non_invariant_baseptr_with_identical_obj2(ptr %A) {
; CHECK-LABEL: 'non_invariant_baseptr_with_identical_obj2'
; CHECK-NEXT: Src: store i32 1, ptr %idx, align 4 --> Dst: store i32 1, ptr %idx, align 4
; CHECK-NEXT: da analyze - none!
;
entry:
br label %loop.i.header

loop.i.header:
%i = phi i32 [ 0, %entry ], [ %i.inc, %loop.i.latch ]
%A1 = getelementptr i32, ptr %A, i32 1
br label %loop.j.header

loop.j.header:
%j = phi i32 [ 0, %loop.i.header ], [ %j.inc, %loop.j.latch ]
%ptr0 = phi ptr [ %A, %loop.i.header ], [ %ptr1, %loop.j.latch ]
%ptr1 = phi ptr [ %A1, %loop.i.header ], [ %ptr0, %loop.j.latch ]
br label %loop.k

loop.k:
%k = phi i32 [ 0, %loop.j.header ], [ %k.inc, %loop.k ]
%idx = getelementptr [42 x [42 x i32]], ptr %ptr0, i32 %i, i32 %k, i32 %j
store i32 1, ptr %idx
%k.inc = add i32 %k, 1
%cmp.k = icmp slt i32 %k.inc, 42
br i1 %cmp.k, label %loop.k, label %loop.j.latch

loop.j.latch:
%j.inc = add i32 %j, 1
%cmp.j = icmp slt i32 %j.inc, 41
br i1 %cmp.j, label %loop.j.header, label %loop.i.latch

loop.i.latch:
%i.inc = add i32 %i, 1
%cmp.i = icmp slt i32 %i.inc, 100
br i1 %cmp.i, label %loop.i.header, label %exit

exit:
ret void
}
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