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[DA] Replace delinearization for fixed size array #161822

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aa3e203
[DA] Replace delinearization for fixed size array
kasuga-fj Oct 3, 2025
66cfa34
Merge branch 'main' into da-replace-delinearize
kasuga-fj Oct 14, 2025
e89cb44
update tests
kasuga-fj Oct 14, 2025
c7dc3af
remove remarks outputs
kasuga-fj Oct 14, 2025
795f2f8
address review comments
kasuga-fj Oct 15, 2025
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34 changes: 16 additions & 18 deletions llvm/lib/Analysis/DependenceAnalysis.cpp
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Expand Up @@ -3504,12 +3504,13 @@ bool DependenceInfo::tryDelinearizeFixedSize(
"expected src and dst scev unknowns to be equal");
});

SmallVector<int, 4> SrcSizes;
SmallVector<int, 4> DstSizes;
if (!tryDelinearizeFixedSizeImpl(SE, Src, SrcAccessFn, SrcSubscripts,
SrcSizes) ||
!tryDelinearizeFixedSizeImpl(SE, Dst, DstAccessFn, DstSubscripts,
DstSizes))
const SCEV *ElemSize = SE->getElementSize(Src);
assert(ElemSize == SE->getElementSize(Dst) && "Different element sizes");
SmallVector<const SCEV *, 4> SrcSizes, DstSizes;
if (!delinearizeFixedSizeArray(*SE, SE->removePointerBase(SrcAccessFn),
SrcSubscripts, SrcSizes, ElemSize) ||
!delinearizeFixedSizeArray(*SE, SE->removePointerBase(DstAccessFn),
DstSubscripts, DstSizes, ElemSize))
return false;

// Check that the two size arrays are non-empty and equal in length and
Expand All @@ -3535,7 +3536,7 @@ bool DependenceInfo::tryDelinearizeFixedSize(
// iff the subscripts are positive and are less than the range of the
// dimension.
if (!DisableDelinearizationChecks) {
auto AllIndicesInRange = [&](SmallVector<int, 4> &DimensionSizes,
auto AllIndicesInRange = [&](ArrayRef<const SCEV *> DimensionSizes,
SmallVectorImpl<const SCEV *> &Subscripts,
Value *Ptr) {
size_t SSize = Subscripts.size();
Expand All @@ -3548,17 +3549,14 @@ bool DependenceInfo::tryDelinearizeFixedSize(
});
return false;
}
if (auto *SType = dyn_cast<IntegerType>(S->getType())) {
const SCEV *Range = SE->getConstant(
ConstantInt::get(SType, DimensionSizes[I - 1], false));
if (!isKnownLessThan(S, Range)) {
LLVM_DEBUG({
dbgs() << "Check failed: !isKnownLessThan(S, Range)\n";
dbgs() << " S: " << *S << "\n"
<< " Range: " << *Range << "\n";
});
return false;
}
const SCEV *Range = DimensionSizes[I - 1];
if (!isKnownLessThan(S, Range)) {
LLVM_DEBUG({
dbgs() << "Check failed: !isKnownLessThan(S, Range)\n";
dbgs() << " S: " << *S << "\n"
<< " Range: " << *Range << "\n";
});
return false;
}
}
return true;
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4 changes: 2 additions & 2 deletions llvm/test/Analysis/DependenceAnalysis/Banerjee.ll
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Expand Up @@ -660,7 +660,7 @@ define void @banerjee7(ptr %A, ptr %B, i64 %m, i64 %n) nounwind uwtable ssp {
; DELIN-NEXT: Src: store i64 0, ptr %arrayidx, align 8 --> Dst: store i64 0, ptr %arrayidx, align 8
; DELIN-NEXT: da analyze - none!
; DELIN-NEXT: Src: store i64 0, ptr %arrayidx, align 8 --> Dst: %0 = load i64, ptr %arrayidx7, align 8
; DELIN-NEXT: da analyze - flow [> <=]!
; DELIN-NEXT: da analyze - consistent flow [-1 0]!
; DELIN-NEXT: Src: store i64 0, ptr %arrayidx, align 8 --> Dst: store i64 %0, ptr %B.addr.11, align 8
; DELIN-NEXT: da analyze - confused!
; DELIN-NEXT: Src: %0 = load i64, ptr %arrayidx7, align 8 --> Dst: %0 = load i64, ptr %arrayidx7, align 8
Expand Down Expand Up @@ -916,7 +916,7 @@ define void @banerjee10(ptr %A, ptr %B, i64 %m, i64 %n) nounwind uwtable ssp {
; DELIN-NEXT: Src: store i64 0, ptr %arrayidx, align 8 --> Dst: store i64 0, ptr %arrayidx, align 8
; DELIN-NEXT: da analyze - none!
; DELIN-NEXT: Src: store i64 0, ptr %arrayidx, align 8 --> Dst: %1 = load i64, ptr %arrayidx6, align 8
; DELIN-NEXT: da analyze - flow [<> 0]!
; DELIN-NEXT: da analyze - flow [-11 0]!
; DELIN-NEXT: Src: store i64 0, ptr %arrayidx, align 8 --> Dst: store i64 %1, ptr %B.addr.11, align 8
; DELIN-NEXT: da analyze - confused!
; DELIN-NEXT: Src: %1 = load i64, ptr %arrayidx6, align 8 --> Dst: %1 = load i64, ptr %arrayidx6, align 8
Expand Down
6 changes: 2 additions & 4 deletions llvm/test/Analysis/DependenceAnalysis/Coupled.ll
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I believe this test will be removed in #160924.

Original file line number Diff line number Diff line change
Expand Up @@ -503,8 +503,7 @@ define void @couple11(ptr %A, ptr %B, i32 %n) nounwind uwtable ssp {
; CHECK-NEXT: Src: store i32 %conv, ptr %arrayidx2, align 4 --> Dst: store i32 %conv, ptr %arrayidx2, align 4
; CHECK-NEXT: da analyze - none!
; CHECK-NEXT: Src: store i32 %conv, ptr %arrayidx2, align 4 --> Dst: %0 = load i32, ptr %arrayidx4, align 4
; CHECK-NEXT: da analyze - flow [0|<] splitable!
; CHECK-NEXT: da analyze - split level = 1, iteration = 9!
; CHECK-NEXT: da analyze - flow [0|<]!
; CHECK-NEXT: Src: store i32 %conv, ptr %arrayidx2, align 4 --> Dst: store i32 %0, ptr %B.addr.01, align 4
; CHECK-NEXT: da analyze - confused!
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx4, align 4 --> Dst: %0 = load i32, ptr %arrayidx4, align 4
Expand Down Expand Up @@ -548,8 +547,7 @@ define void @couple12(ptr %A, ptr %B, i32 %n) nounwind uwtable ssp {
; CHECK-NEXT: Src: store i32 %conv, ptr %arrayidx2, align 4 --> Dst: store i32 %conv, ptr %arrayidx2, align 4
; CHECK-NEXT: da analyze - none!
; CHECK-NEXT: Src: store i32 %conv, ptr %arrayidx2, align 4 --> Dst: %0 = load i32, ptr %arrayidx4, align 4
; CHECK-NEXT: da analyze - flow [<] splitable!
; CHECK-NEXT: da analyze - split level = 1, iteration = 11!
; CHECK-NEXT: da analyze - flow [<]!
; CHECK-NEXT: Src: store i32 %conv, ptr %arrayidx2, align 4 --> Dst: store i32 %0, ptr %B.addr.01, align 4
; CHECK-NEXT: da analyze - confused!
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx4, align 4 --> Dst: %0 = load i32, ptr %arrayidx4, align 4
Expand Down
3 changes: 1 addition & 2 deletions llvm/test/Analysis/DependenceAnalysis/DifferentOffsets.ll
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Expand Up @@ -149,11 +149,10 @@ define void @multidim_accesses(ptr %A) {
; CHECK-NEXT: Src: store i32 1, ptr %idx0, align 4 --> Dst: store i32 1, ptr %idx0, align 4
; CHECK-NEXT: da analyze - none!
; CHECK-NEXT: Src: store i32 1, ptr %idx0, align 4 --> Dst: store i32 1, ptr %idx1, align 4
; CHECK-NEXT: da analyze - consistent output [0 0 0|<]!
; CHECK-NEXT: da analyze - output [<= * *|<]!
; CHECK-NEXT: Src: store i32 1, ptr %idx1, align 4 --> Dst: store i32 1, ptr %idx1, align 4
; CHECK-NEXT: da analyze - none!
;
; FIXME: the dependence distance is not constant. Distance vector should be [* * *|<]!
Comment on lines -152 to -156
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This change means fixing a known issue.

; for (i = 0; i < 256; i++)
; for (j = 0; j < 256; j++)
; for (k = 0; k < 256; k++) {
Expand Down
5 changes: 5 additions & 0 deletions llvm/test/Analysis/DependenceAnalysis/Invariant.ll
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Expand Up @@ -2,6 +2,11 @@
; RUN: opt < %s -disable-output "-passes=print<da>" -aa-pipeline=basic-aa 2>&1 \
; RUN: | FileCheck %s

; XFAIL: *
; Currently fails since delinearization doesn't work as expected, due to the
; inconsistency in the estimated array sizes between `rr[i][j]` and `rr[j][j]`.
; The latter is now regarded as an access to a 1D array.

; Test for a bug, which caused an assert when an invalid
; SCEVAddRecExpr is created in addToCoefficient.

Expand Down
4 changes: 3 additions & 1 deletion llvm/test/Analysis/DependenceAnalysis/NonCanonicalizedSubscript.ll
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Expand Up @@ -47,6 +47,8 @@ for.end:
; }
; }
; Extends the previous example to coupled MIV subscripts.
;
; FIXME: Currently delinearization does not work as expected.


@a = global [10004 x [10004 x i32]] zeroinitializer, align 16
Expand All @@ -57,7 +59,7 @@ define void @coupled_miv_type_mismatch(i32 %n) #0 {
; CHECK-NEXT: Src: %2 = load i32, ptr %arrayidx5, align 4 --> Dst: %2 = load i32, ptr %arrayidx5, align 4
; CHECK-NEXT: da analyze - none!
; CHECK-NEXT: Src: %2 = load i32, ptr %arrayidx5, align 4 --> Dst: store i32 %add6, ptr %arrayidx10, align 4
; CHECK-NEXT: da analyze - consistent anti [1 -2]!
; CHECK-NEXT: da analyze - anti [< >]!
; CHECK-NEXT: Src: store i32 %add6, ptr %arrayidx10, align 4 --> Dst: store i32 %add6, ptr %arrayidx10, align 4
; CHECK-NEXT: da analyze - none!
;
Expand Down
2 changes: 1 addition & 1 deletion llvm/test/Analysis/DependenceAnalysis/PR51512.ll
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Expand Up @@ -10,7 +10,7 @@ define void @foo() {
; CHECK-NEXT: Src: store i32 42, ptr %getelementptr, align 1 --> Dst: store i32 42, ptr %getelementptr, align 1
; CHECK-NEXT: da analyze - consistent output [0 S]!
; CHECK-NEXT: Src: store i32 42, ptr %getelementptr, align 1 --> Dst: store i32 0, ptr %getelementptr5, align 1
; CHECK-NEXT: da analyze - output [0 *|<]!
; CHECK-NEXT: da analyze - output [0 <=|<]!
; CHECK-NEXT: Src: store i32 0, ptr %getelementptr5, align 1 --> Dst: store i32 0, ptr %getelementptr5, align 1
; CHECK-NEXT: da analyze - none!
;
Expand Down
3 changes: 2 additions & 1 deletion llvm/test/Analysis/DependenceAnalysis/Propagating.ll
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Expand Up @@ -437,7 +437,8 @@ define void @prop7(ptr %A, ptr %B, i32 %n) nounwind uwtable ssp {
; CHECK-NEXT: Src: store i32 %conv, ptr %arrayidx7, align 4 --> Dst: store i32 %conv, ptr %arrayidx7, align 4
; CHECK-NEXT: da analyze - none!
; CHECK-NEXT: Src: store i32 %conv, ptr %arrayidx7, align 4 --> Dst: %0 = load i32, ptr %arrayidx13, align 4
; CHECK-NEXT: da analyze - flow [* <>]!
; CHECK-NEXT: da analyze - flow [* -38] splitable!
; CHECK-NEXT: da analyze - split level = 1, iteration = 4!
; CHECK-NEXT: Src: store i32 %conv, ptr %arrayidx7, align 4 --> Dst: store i32 %0, ptr %B.addr.11, align 4
; CHECK-NEXT: da analyze - confused!
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx13, align 4 --> Dst: %0 = load i32, ptr %arrayidx13, align 4
Expand Down
2 changes: 1 addition & 1 deletion llvm/test/Analysis/DependenceAnalysis/SameSDLoops.ll
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Expand Up @@ -148,7 +148,7 @@ define void @non_samebd0(ptr %A) nounwind uwtable ssp {
; CHECK-NEXT: Src: store i64 %i.013, ptr %arrayidx12, align 8 --> Dst: store i64 %i.013, ptr %arrayidx12, align 8
; CHECK-NEXT: da analyze - none!
; CHECK-NEXT: Src: store i64 %i.013, ptr %arrayidx12, align 8 --> Dst: store i64 %l17.04, ptr %arrayidx24, align 8
; CHECK-NEXT: da analyze - output [-4 -3]!
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Seems regression, but less important, I believe.

; CHECK-NEXT: da analyze - output [> *]!
; CHECK-NEXT: Src: store i64 %l17.04, ptr %arrayidx24, align 8 --> Dst: store i64 %l17.04, ptr %arrayidx24, align 8
; CHECK-NEXT: da analyze - none!
;
Expand Down
6 changes: 3 additions & 3 deletions llvm/test/Analysis/DependenceAnalysis/Separability.ll
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This also will be removed in #160924.

Original file line number Diff line number Diff line change
Expand Up @@ -182,7 +182,7 @@ define void @sep2(ptr %A, ptr %B, i32 %n) nounwind uwtable ssp {
; CHECK-NEXT: Src: store i32 %conv, ptr %arrayidx12, align 4 --> Dst: store i32 %conv, ptr %arrayidx12, align 4
; CHECK-NEXT: da analyze - consistent output [0 S 0 0]!
; CHECK-NEXT: Src: store i32 %conv, ptr %arrayidx12, align 4 --> Dst: %0 = load i32, ptr %arrayidx19, align 4
; CHECK-NEXT: da analyze - flow [> * * -10]!
; CHECK-NEXT: da analyze - flow [* * * <>]!
; CHECK-NEXT: Src: store i32 %conv, ptr %arrayidx12, align 4 --> Dst: store i32 %0, ptr %B.addr.31, align 4
; CHECK-NEXT: da analyze - confused!
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx19, align 4 --> Dst: %0 = load i32, ptr %arrayidx19, align 4
Expand Down Expand Up @@ -262,9 +262,9 @@ for.end28: ; preds = %for.inc26
define void @sep3(ptr %A, ptr %B, i32 %n) nounwind uwtable ssp {
; CHECK-LABEL: 'sep3'
; CHECK-NEXT: Src: store i32 %conv, ptr %arrayidx13, align 4 --> Dst: store i32 %conv, ptr %arrayidx13, align 4
; CHECK-NEXT: da analyze - consistent output [0 S 0 0]!
; CHECK-NEXT: da analyze - output [0 S 0 0]!
; CHECK-NEXT: Src: store i32 %conv, ptr %arrayidx13, align 4 --> Dst: %0 = load i32, ptr %arrayidx20, align 4
; CHECK-NEXT: da analyze - flow [> * * *]!
; CHECK-NEXT: da analyze - flow [* * * *|<]!
; CHECK-NEXT: Src: store i32 %conv, ptr %arrayidx13, align 4 --> Dst: store i32 %0, ptr %B.addr.31, align 4
; CHECK-NEXT: da analyze - confused!
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx20, align 4 --> Dst: %0 = load i32, ptr %arrayidx20, align 4
Expand Down
4 changes: 2 additions & 2 deletions llvm/test/Transforms/LoopInterchange/legality-check.ll
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Expand Up @@ -149,10 +149,10 @@ exit:
;; for (int k = 0; k < 19; k++)
;; b[i][j][k] = b[i][5][k + 1];
;;
;; The direction vector of `b` is [= * <]. We cannot interchange all the loops.
;; The direction vector of `b` is [= * *]. We cannot interchange all the loops.

; CHECK: Dependency matrix before interchange:
; CHECK-NEXT: = * <
; CHECK-NEXT: = * *
Comment on lines +152 to +155
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I remember I added this test in #139690. It should be sufficient to ensure no interchange occurs for this case.

; CHECK-NEXT: Processing InnerLoopId = 2 and OuterLoopId = 1
; CHECK-NEXT: Failed interchange InnerLoopId = 2 and OuterLoopId = 1 due to dependence
; CHECK-NEXT: Not interchanging loops. Cannot prove legality.
Expand Down
11 changes: 6 additions & 5 deletions llvm/test/Transforms/LoopInterchange/outer-dependency-lte.ll
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Expand Up @@ -15,15 +15,16 @@
;;
;; The entry of the direction vector for the outermost loop is `DVEntry::LE`.
;; We need to treat this as `*`, not `<`. See issue #123920 for details.
;; In conclusion, we must not interchange the loops.

; CHECK: --- !Missed
; CHECK-NEXT: Pass: loop-interchange
; CHECK-NEXT: Name: Dependence
; CHECK-NEXT: Function: f
; CHECK: --- !Missed
; CHECK: --- !Missed
; CHECK-NEXT: Pass: loop-interchange
; CHECK-NEXT: Name: Dependence
; CHECK-NEXT: Function: f
; CHECK-NEXT: Args:
; CHECK-NEXT: - String: All loops have dependencies in all directions.
; CHECK-NEXT: ...


@a = dso_local global [16 x [16 x [16 x i32]]] zeroinitializer, align 4

Expand Down
3 changes: 3 additions & 0 deletions llvm/test/Transforms/LoopUnrollAndJam/dependencies_multidims.ll
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Expand Up @@ -3,6 +3,9 @@

target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"

; XFAIL: *
; The transformation seems to have succeeded "accidentally".

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Maybe conflicting with #156578. I will rebase after that PR is merged.

; CHECK-LABEL: sub_sub_less
; CHECK: %j = phi
; CHECK-NOT: %j.1 = phi
Expand Down