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[Delinearization] Add validation for large size arrays
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10 files changed

+89
-34
lines changed

10 files changed

+89
-34
lines changed

‎llvm/lib/Analysis/Delinearization.cpp‎

Lines changed: 51 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -747,6 +747,20 @@ bool llvm::validateDelinearizationResult(ScalarEvolution &SE,
747747
ArrayRef<const SCEV *> Sizes,
748748
ArrayRef<const SCEV *> Subscripts,
749749
const Value *Ptr) {
750+
// Sizes and Subscripts are as follows:
751+
//
752+
// Sizes: [UNK][S_2]...[S_n]
753+
// Subscripts: [I_1][I_2]...[I_n]
754+
//
755+
// where the size of the outermost dimension is unknown (UNK).
756+
757+
auto MulOverflow = [&](const SCEV *A, const SCEV *B) -> const SCEV * {
758+
if (!SE.willNotOverflow(Instruction::Mul, /*IsSigned=*/true, A, B))
759+
return nullptr;
760+
return SE.getMulExpr(A, B);
761+
};
762+
763+
// Range check: 0 <= I_k < S_k for k = 2..n.
750764
for (size_t I = 1; I < Sizes.size(); ++I) {
751765
const SCEV *Size = Sizes[I - 1];
752766
const SCEV *Subscript = Subscripts[I];
@@ -755,6 +769,43 @@ bool llvm::validateDelinearizationResult(ScalarEvolution &SE,
755769
if (!isKnownLessThan(&SE, Subscript, Size))
756770
return false;
757771
}
772+
773+
// The offset computation is as follows:
774+
//
775+
// Offset = I_n +
776+
// S_n * I_{n-1} +
777+
// ... +
778+
// (S_2 * ... * S_n) * I_1
779+
//
780+
// Regarding this as a function from (I_1, I_2, ..., I_n) to integers, it
781+
// must be injective. To guarantee it, the above calculation must not
782+
// overflow. Since we have already checked that 0 <= I_k < S_k for k = 2..n,
783+
// the minimum and maximum values occur in the following cases:
784+
//
785+
// Min = [I_1][0]...[0] = S_2 * ... * S_n * I_1
786+
// Max = [I_1][S_2-1]...[S_n-1]
787+
// = (S_2 * ... * S_n) * I_1 +
788+
// (S_2 * ... * S_{n-1}) * (S_2 - 1) +
789+
// ... +
790+
// (S_n - 1)
791+
// = (S_2 * ... * S_n) * I_1 +
792+
// (S_2 * ... * S_n) - 1 (can be proved by induction)
793+
//
794+
const SCEV *Prod = SE.getOne(Sizes[0]->getType());
795+
for (const SCEV *Size : drop_end(Sizes)) {
796+
Prod = MulOverflow(Prod, Size);
797+
if (!Prod)
798+
return false;
799+
}
800+
const SCEV *Min = MulOverflow(Prod, Subscripts[0]);
801+
if (!Min)
802+
return false;
803+
804+
// Over-approximate Max as Prod * I_1 + Prod (ignoring the -1).
805+
if (!SE.willNotOverflow(Instruction::Add, /*IsSigned=*/true, Min,
806+
Subscripts[0]))
807+
return false;
808+
758809
return true;
759810
}
760811

‎llvm/test/Analysis/Delinearization/constant_functions_multi_dim.ll‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -11,7 +11,7 @@ define void @mat_mul(ptr %C, ptr %A, ptr %B, i64 %N) !kernel_arg_addr_space !2 !
1111
; CHECK-NEXT: Base offset: %A
1212
; CHECK-NEXT: ArrayDecl[UnknownSize][%N] with elements of 4 bytes.
1313
; CHECK-NEXT: ArrayRef[%call][{0,+,1}<nuw><nsw><%for.inc>]
14-
; CHECK-NEXT: Delinearization validation: Succeeded
14+
; CHECK-NEXT: Delinearization validation: Failed
1515
; CHECK-EMPTY:
1616
; CHECK-NEXT: Inst: %tmp5 = load float, ptr %arrayidx4, align 4
1717
; CHECK-NEXT: AccessFunction: {(4 * %call1),+,(4 * %N)}<%for.inc>

‎llvm/test/Analysis/Delinearization/multidim_only_ivs_2d.ll‎

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -16,14 +16,14 @@ define void @foo(i64 %n, i64 %m, ptr %A) {
1616
; CHECK-NEXT: Base offset: %A
1717
; CHECK-NEXT: ArrayDecl[UnknownSize][%m] with elements of 8 bytes.
1818
; CHECK-NEXT: ArrayRef[{0,+,1}<nuw><nsw><%for.i>][{0,+,1}<nuw><nsw><%for.j>]
19-
; CHECK-NEXT: Delinearization validation: Succeeded
19+
; CHECK-NEXT: Delinearization validation: Failed
2020
; CHECK-EMPTY:
2121
; CHECK-NEXT: Inst: store double %val, ptr %arrayidx, align 8
2222
; CHECK-NEXT: AccessFunction: {{\{\{}}0,+,(8 * %m)}<%for.i>,+,8}<%for.j>
2323
; CHECK-NEXT: Base offset: %A
2424
; CHECK-NEXT: ArrayDecl[UnknownSize][%m] with elements of 8 bytes.
2525
; CHECK-NEXT: ArrayRef[{0,+,1}<nuw><nsw><%for.i>][{0,+,1}<nuw><nsw><%for.j>]
26-
; CHECK-NEXT: Delinearization validation: Succeeded
26+
; CHECK-NEXT: Delinearization validation: Failed
2727
;
2828
entry:
2929
br label %for.i

‎llvm/test/Analysis/Delinearization/multidim_only_ivs_3d.ll‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -16,7 +16,7 @@ define void @foo(i64 %n, i64 %m, i64 %o, ptr %A) {
1616
; CHECK-NEXT: Base offset: %A
1717
; CHECK-NEXT: ArrayDecl[UnknownSize][%m][%o] with elements of 8 bytes.
1818
; CHECK-NEXT: ArrayRef[{0,+,1}<nuw><nsw><%for.i>][{0,+,1}<nuw><nsw><%for.j>][{0,+,1}<nuw><nsw><%for.k>]
19-
; CHECK-NEXT: Delinearization validation: Succeeded
19+
; CHECK-NEXT: Delinearization validation: Failed
2020
;
2121
entry:
2222
br label %for.i

‎llvm/test/Analysis/Delinearization/multidim_two_accesses_different_delinearization.ll‎

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -19,14 +19,14 @@ define void @foo(i64 %n, i64 %m, ptr %A) {
1919
; CHECK-NEXT: Base offset: %A
2020
; CHECK-NEXT: ArrayDecl[UnknownSize][%m] with elements of 8 bytes.
2121
; CHECK-NEXT: ArrayRef[{0,+,1}<nuw><nsw><%for.i>][{0,+,1}<nuw><nsw><%for.j>]
22-
; CHECK-NEXT: Delinearization validation: Succeeded
22+
; CHECK-NEXT: Delinearization validation: Failed
2323
; CHECK-EMPTY:
2424
; CHECK-NEXT: Inst: store double 1.000000e+00, ptr %arrayidx1, align 8
2525
; CHECK-NEXT: AccessFunction: {{\{\{}}0,+,8}<%for.i>,+,(8 * %n)}<%for.j>
2626
; CHECK-NEXT: Base offset: %A
2727
; CHECK-NEXT: ArrayDecl[UnknownSize][%n] with elements of 8 bytes.
2828
; CHECK-NEXT: ArrayRef[{0,+,1}<nuw><nsw><%for.j>][{0,+,1}<nuw><nsw><%for.i>]
29-
; CHECK-NEXT: Delinearization validation: Succeeded
29+
; CHECK-NEXT: Delinearization validation: Failed
3030
;
3131
entry:
3232
br label %for.i

‎llvm/test/Analysis/Delinearization/validation_large_size.ll‎

Lines changed: 5 additions & 8 deletions
Original file line numberDiff line numberDiff line change
@@ -1,12 +1,9 @@
11
; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py UTC_ARGS: --version 6
22
; RUN: opt < %s -passes='print<delinearization>' --delinearize-use-fixed-size-array-heuristic -disable-output 2>&1 | FileCheck %s
33

4-
; FIXME: When considering an array as a function from subcripts to addresses,
5-
; it should be injective. That is, different subscript tuples should map to
6-
; different addresses. Currently, delinearization doesn't guarantee this
7-
; property, especially when the inferred array size is very large so that the
8-
; product of dimensions may overflow. The delinearization validation should
9-
; consider such cases as invalid.
4+
; When considering an array as a function from subcripts to addresses, it
5+
; should be injective. That is, different subscript tuples should map to
6+
; different addresses.
107

118
; for (i = 0; i < (1ULL << 60); i++)
129
; for (j = 0; j < 256; j++)
@@ -23,7 +20,7 @@ define void @large_size_fixed(ptr %A) {
2320
; CHECK-NEXT: Base offset: %A
2421
; CHECK-NEXT: ArrayDecl[UnknownSize][256] with elements of 1 bytes.
2522
; CHECK-NEXT: ArrayRef[{0,+,1}<nuw><nsw><%for.i.header>][{0,+,1}<nuw><nsw><%for.j>]
26-
; CHECK-NEXT: Delinearization validation: Succeeded
23+
; CHECK-NEXT: Delinearization validation: Failed
2724
;
2825
entry:
2926
br label %for.i.header
@@ -75,7 +72,7 @@ define void @large_size_parametric(i64 %n, i64 %m, i64 %o, ptr %A) {
7572
; CHECK-NEXT: Base offset: %A
7673
; CHECK-NEXT: ArrayDecl[UnknownSize][%m][%o] with elements of 1 bytes.
7774
; CHECK-NEXT: ArrayRef[{0,+,1}<nuw><nsw><%for.i.header>][{0,+,1}<nuw><nsw><%for.j.header>][{0,+,1}<nuw><nsw><%for.k.header>]
78-
; CHECK-NEXT: Delinearization validation: Succeeded
75+
; CHECK-NEXT: Delinearization validation: Failed
7976
;
8077
entry:
8178
%guard.i = icmp sgt i64 %n, 0

‎llvm/test/Analysis/DependenceAnalysis/DADelin.ll‎

Lines changed: 16 additions & 16 deletions
Original file line numberDiff line numberDiff line change
@@ -13,11 +13,11 @@ target triple = "thumbv8m.main-arm-none-eabi"
1313
define void @t1(i32 %n, i32 %m, i32 %o, ptr nocapture %A) {
1414
; CHECK-LABEL: 't1'
1515
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx, align 4 --> Dst: %0 = load i32, ptr %arrayidx, align 4
16-
; CHECK-NEXT: da analyze - none!
16+
; CHECK-NEXT: da analyze - input [* * *]!
1717
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx, align 4 --> Dst: store i32 %add12, ptr %arrayidx, align 4
18-
; CHECK-NEXT: da analyze - consistent anti [0 0 0|<]!
18+
; CHECK-NEXT: da analyze - anti [* * *|<]!
1919
; CHECK-NEXT: Src: store i32 %add12, ptr %arrayidx, align 4 --> Dst: store i32 %add12, ptr %arrayidx, align 4
20-
; CHECK-NEXT: da analyze - none!
20+
; CHECK-NEXT: da analyze - output [* * *]!
2121
;
2222
entry:
2323
%cmp49 = icmp sgt i32 %n, 0
@@ -78,7 +78,7 @@ for.cond.cleanup: ; preds = %for.cond.cleanup3,
7878
define void @t2(i32 %n, i32 %m, i32 %o, ptr nocapture %A) {
7979
; CHECK-LABEL: 't2'
8080
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx, align 4 --> Dst: %0 = load i32, ptr %arrayidx, align 4
81-
; CHECK-NEXT: da analyze - none!
81+
; CHECK-NEXT: da analyze - input [* * *]!
8282
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx, align 4 --> Dst: store i32 %add12, ptr %arrayidx2, align 4
8383
; CHECK-NEXT: da analyze - anti [* * *|<]!
8484
; CHECK-NEXT: Src: store i32 %add12, ptr %arrayidx2, align 4 --> Dst: store i32 %add12, ptr %arrayidx2, align 4
@@ -145,7 +145,7 @@ for.cond.cleanup: ; preds = %for.cond.cleanup3,
145145
define void @t3(i32 %n, i32 %m, i32 %o, ptr nocapture %A) {
146146
; CHECK-LABEL: 't3'
147147
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx, align 4 --> Dst: %0 = load i32, ptr %arrayidx, align 4
148-
; CHECK-NEXT: da analyze - none!
148+
; CHECK-NEXT: da analyze - input [* * *]!
149149
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx, align 4 --> Dst: store i32 %add12, ptr %arrayidx2, align 4
150150
; CHECK-NEXT: da analyze - anti [* * *|<]!
151151
; CHECK-NEXT: Src: store i32 %add12, ptr %arrayidx2, align 4 --> Dst: store i32 %add12, ptr %arrayidx2, align 4
@@ -212,7 +212,7 @@ for.cond.cleanup: ; preds = %for.cond.cleanup3,
212212
define void @t4(i32 %n, i32 %m, i32 %o, ptr nocapture %A) {
213213
; CHECK-LABEL: 't4'
214214
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx, align 4 --> Dst: %0 = load i32, ptr %arrayidx, align 4
215-
; CHECK-NEXT: da analyze - none!
215+
; CHECK-NEXT: da analyze - input [* * *]!
216216
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx, align 4 --> Dst: store i32 %add12, ptr %arrayidx2, align 4
217217
; CHECK-NEXT: da analyze - anti [* * *|<]!
218218
; CHECK-NEXT: Src: store i32 %add12, ptr %arrayidx2, align 4 --> Dst: store i32 %add12, ptr %arrayidx2, align 4
@@ -279,7 +279,7 @@ for.cond.cleanup: ; preds = %for.cond.cleanup3,
279279
define void @t5(i32 %n, i32 %m, i32 %o, ptr nocapture %A) {
280280
; CHECK-LABEL: 't5'
281281
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx, align 4 --> Dst: %0 = load i32, ptr %arrayidx, align 4
282-
; CHECK-NEXT: da analyze - none!
282+
; CHECK-NEXT: da analyze - input [* * *]!
283283
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx, align 4 --> Dst: store i32 %add12, ptr %arrayidx2, align 4
284284
; CHECK-NEXT: da analyze - anti [* * *|<]!
285285
; CHECK-NEXT: Src: store i32 %add12, ptr %arrayidx2, align 4 --> Dst: store i32 %add12, ptr %arrayidx2, align 4
@@ -346,11 +346,11 @@ for.cond.cleanup: ; preds = %for.cond.cleanup3,
346346
define void @t6(i32 %n, i32 %m, i32 %o, ptr nocapture %A) {
347347
; CHECK-LABEL: 't6'
348348
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx, align 4 --> Dst: %0 = load i32, ptr %arrayidx, align 4
349-
; CHECK-NEXT: da analyze - none!
349+
; CHECK-NEXT: da analyze - input [* * *]!
350350
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx, align 4 --> Dst: store i32 %add12, ptr %arrayidx2, align 4
351-
; CHECK-NEXT: da analyze - consistent anti [-1 0 0]!
351+
; CHECK-NEXT: da analyze - anti [* * *|<]!
352352
; CHECK-NEXT: Src: store i32 %add12, ptr %arrayidx2, align 4 --> Dst: store i32 %add12, ptr %arrayidx2, align 4
353-
; CHECK-NEXT: da analyze - none!
353+
; CHECK-NEXT: da analyze - output [* * *]!
354354
;
355355
entry:
356356
%cmp49 = icmp sgt i32 %n, 0
@@ -414,11 +414,11 @@ for.cond.cleanup: ; preds = %for.cond.cleanup3,
414414
define void @t7(i32 %n, i32 %m, i32 %o, ptr nocapture %A) {
415415
; CHECK-LABEL: 't7'
416416
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx, align 4 --> Dst: %0 = load i32, ptr %arrayidx, align 4
417-
; CHECK-NEXT: da analyze - none!
417+
; CHECK-NEXT: da analyze - input [* * *]!
418418
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx, align 4 --> Dst: store i32 %add12, ptr %arrayidx2, align 4
419-
; CHECK-NEXT: da analyze - consistent anti [1 0 0]!
419+
; CHECK-NEXT: da analyze - anti [* * *|<]!
420420
; CHECK-NEXT: Src: store i32 %add12, ptr %arrayidx2, align 4 --> Dst: store i32 %add12, ptr %arrayidx2, align 4
421-
; CHECK-NEXT: da analyze - none!
421+
; CHECK-NEXT: da analyze - output [* * *]!
422422
;
423423
entry:
424424
%cmp49 = icmp sgt i32 %n, 0
@@ -482,11 +482,11 @@ for.cond.cleanup: ; preds = %for.cond.cleanup3,
482482
define void @t8(i32 %n, i32 %m, i32 %o, ptr nocapture %A) {
483483
; CHECK-LABEL: 't8'
484484
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx, align 4 --> Dst: %0 = load i32, ptr %arrayidx, align 4
485-
; CHECK-NEXT: da analyze - none!
485+
; CHECK-NEXT: da analyze - input [* * *]!
486486
; CHECK-NEXT: Src: %0 = load i32, ptr %arrayidx, align 4 --> Dst: store i32 %add12, ptr %arrayidx2, align 4
487-
; CHECK-NEXT: da analyze - consistent anti [0 0 1]!
487+
; CHECK-NEXT: da analyze - anti [* * *|<]!
488488
; CHECK-NEXT: Src: store i32 %add12, ptr %arrayidx2, align 4 --> Dst: store i32 %add12, ptr %arrayidx2, align 4
489-
; CHECK-NEXT: da analyze - none!
489+
; CHECK-NEXT: da analyze - output [* * *]!
490490
;
491491
entry:
492492
%cmp49 = icmp sgt i32 %n, 0

‎llvm/test/Analysis/DependenceAnalysis/DifferentOffsets.ll‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -100,7 +100,7 @@ define void @linearized_accesses(i64 %n, i64 %m, i64 %o, ptr %A) {
100100
; CHECK-NEXT: Src: store i32 1, ptr %idx0, align 4 --> Dst: store i32 1, ptr %idx1, align 4
101101
; CHECK-NEXT: da analyze - output [* * *|<]!
102102
; CHECK-NEXT: Src: store i32 1, ptr %idx1, align 4 --> Dst: store i32 1, ptr %idx1, align 4
103-
; CHECK-NEXT: da analyze - none!
103+
; CHECK-NEXT: da analyze - output [* * *]!
104104
;
105105
entry:
106106
br label %for.i

‎llvm/test/Analysis/DependenceAnalysis/StrongSIV.ll‎

Lines changed: 7 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -536,9 +536,13 @@ for.end: ; preds = %for.body
536536
;; A[i] = 0;
537537

538538
define void @strong11(ptr %A) nounwind uwtable ssp {
539-
; CHECK-LABEL: 'strong11'
540-
; CHECK-NEXT: Src: store i32 0, ptr %arrayidx, align 4 --> Dst: store i32 0, ptr %arrayidx, align 4
541-
; CHECK-NEXT: da analyze - consistent output [0 S]!
539+
; CHECK-ALL-LABEL: 'strong11'
540+
; CHECK-ALL-NEXT: Src: store i32 0, ptr %arrayidx, align 4 --> Dst: store i32 0, ptr %arrayidx, align 4
541+
; CHECK-ALL-NEXT: da analyze - none!
542+
;
543+
; CHECK-STRONG-SIV-LABEL: 'strong11'
544+
; CHECK-STRONG-SIV-NEXT: Src: store i32 0, ptr %arrayidx, align 4 --> Dst: store i32 0, ptr %arrayidx, align 4
545+
; CHECK-STRONG-SIV-NEXT: da analyze - consistent output [0 S]!
542546
;
543547
entry:
544548
br label %for.cond1.preheader

‎llvm/test/Transforms/LICM/lnicm.ll‎

Lines changed: 3 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -3,6 +3,9 @@
33
; RUN: opt -aa-pipeline=basic-aa -passes='loop-mssa(lnicm),loop(loop-interchange)' -cache-line-size=64 -S %s | FileCheck %s --check-prefixes LNICM
44
; RUN: opt -aa-pipeline=basic-aa -passes='loop-mssa(licm),loop(loop-interchange)' -cache-line-size=64 -S %s | FileCheck %s --check-prefixes LICM
55

6+
; XFAIL: *
7+
; Loop interchange currently fails due to a failure in dependence analysis.
8+
69
; This test represents the following function:
710
; void test(int n, int m, int x[m][n], int y[n], int *z) {
811
; for (int k = 0; k < n; k++) {

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