[llvm] [DA] Add tests where dependencies are missed due to overflow (NFC) (PR #164246)

Ryotaro Kasuga via llvm-commits llvm-commits at lists.llvm.org
Wed Oct 29 03:43:44 PDT 2025


https://github.com/kasuga-fj updated https://github.com/llvm/llvm-project/pull/164246

>From 16601d997d72ffb9ef714e56fc8819967a89e8a2 Mon Sep 17 00:00:00 2001
From: Ryotaro Kasuga <kasuga.ryotaro at fujitsu.com>
Date: Fri, 17 Oct 2025 13:26:38 +0000
Subject: [PATCH 1/4] [DA] Add tests where dependencies are missed due to
 overflow

---
 .../DependenceAnalysis/gcd-miv-overflow.ll    |  63 +++++++++
 .../DependenceAnalysis/strong-siv-overflow.ll |  72 ++++++++++
 .../symbolic-rdiv-overflow.ll                 | 128 ++++++++++++++++++
 .../weak-crossing-siv-overflow.ll             | 122 +++++++++++++++++
 .../weak-zero-siv-overflow.ll                 | 121 +++++++++++++++++
 5 files changed, 506 insertions(+)
 create mode 100644 llvm/test/Analysis/DependenceAnalysis/gcd-miv-overflow.ll
 create mode 100644 llvm/test/Analysis/DependenceAnalysis/strong-siv-overflow.ll
 create mode 100644 llvm/test/Analysis/DependenceAnalysis/symbolic-rdiv-overflow.ll
 create mode 100644 llvm/test/Analysis/DependenceAnalysis/weak-crossing-siv-overflow.ll
 create mode 100644 llvm/test/Analysis/DependenceAnalysis/weak-zero-siv-overflow.ll

diff --git a/llvm/test/Analysis/DependenceAnalysis/gcd-miv-overflow.ll b/llvm/test/Analysis/DependenceAnalysis/gcd-miv-overflow.ll
new file mode 100644
index 0000000000000..724b347b56f3a
--- /dev/null
+++ b/llvm/test/Analysis/DependenceAnalysis/gcd-miv-overflow.ll
@@ -0,0 +1,63 @@
+; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py UTC_ARGS: --version 6
+; RUN: opt < %s -disable-output "-passes=print<da>" 2>&1 | FileCheck %s
+; RUN: opt < %s -disable-output "-passes=print<da>" -da-enable-dependence-test=gcd-miv 2>&1 \
+; RUN:     | FileCheck %s --check-prefix=CHECK-GCD-MIV
+
+; offset0 = 4;
+; offset1 = 0;
+; for (i = 0; i < 100; i++) {
+;   A[offset0] = 1;
+;   A[offset1] = 2;
+;   offset0 += 3*m;
+;   offset1 += 3;
+; }
+;
+; FIXME: DependenceAnalysis currently detects no dependency between the two
+; stores, but it does exist. E.g., consider `m` is 12297829382473034411, which
+; is a modular multiplicative inverse of 3 under modulo 2^64. Then `offset0` is
+; effectively `i + 4`, so accesses will be as follows:
+;
+;   - A[offset0] : A[4], A[5], A[6], ...
+;   - A[offset1] : A[0], A[3], A[6], ...
+;
+; The root cause is that DA assumes `3*m` begin a multiple of 3 in mathematical
+; sense, which isn't necessarily true due to overflow.
+;
+define void @gcdmiv_coef_ovfl(ptr %A, i64 %m) {
+; CHECK-LABEL: 'gcdmiv_coef_ovfl'
+; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
+; CHECK-NEXT:    da analyze - none!
+; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-NEXT:    da analyze - none!
+; CHECK-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-NEXT:    da analyze - none!
+;
+; CHECK-GCD-MIV-LABEL: 'gcdmiv_coef_ovfl'
+; CHECK-GCD-MIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
+; CHECK-GCD-MIV-NEXT:    da analyze - consistent output [*]!
+; CHECK-GCD-MIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-GCD-MIV-NEXT:    da analyze - none!
+; CHECK-GCD-MIV-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-GCD-MIV-NEXT:    da analyze - consistent output [*]!
+;
+entry:
+  %step = mul i64 3, %m
+  br label %loop
+
+loop:
+  %i = phi i64 [ 0, %entry ], [ %i.inc, %loop ]
+  %offset.0 = phi i64 [ 4, %entry ] , [ %offset.0.next, %loop ]
+  %offset.1 = phi i64 [ 0, %entry ] , [ %offset.1.next, %loop ]
+  %gep.0 = getelementptr inbounds i8, ptr %A, i64 %offset.0
+  %gep.1 = getelementptr inbounds i8, ptr %A, i64 %offset.1
+  store i8 1, ptr %gep.0
+  store i8 2, ptr %gep.1
+  %i.inc = add nuw nsw i64 %i, 1
+  %offset.0.next = add nsw i64 %offset.0, %step
+  %offset.1.next = add nsw i64 %offset.1, 3
+  %ec = icmp eq i64 %i.inc, 100
+  br i1 %ec, label %exit, label %loop
+
+exit:
+  ret void
+}
diff --git a/llvm/test/Analysis/DependenceAnalysis/strong-siv-overflow.ll b/llvm/test/Analysis/DependenceAnalysis/strong-siv-overflow.ll
new file mode 100644
index 0000000000000..559f4858612e5
--- /dev/null
+++ b/llvm/test/Analysis/DependenceAnalysis/strong-siv-overflow.ll
@@ -0,0 +1,72 @@
+; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py UTC_ARGS: --version 6
+; RUN: opt < %s -disable-output "-passes=print<da>" 2>&1 | FileCheck %s
+; RUN: opt < %s -disable-output "-passes=print<da>" -da-enable-dependence-test=strong-siv 2>&1 \
+; RUN:     | FileCheck %s --check-prefix=CHECK-STRONG-SIV
+
+; offset0 = -2;
+; offset1 = -4;
+; for (i = 0; i < (1LL << 62); i++, offset0 += 2, offset1 += 2) {
+;   if (0 <= offset0)
+;     A[offset0] = 1;
+;   if (0 <= offset1)
+;     A[offset1] = 2;
+; }
+;
+; FIXME: DependenceAnalysis currently detects no dependency between the two
+; stores, but it does exist.
+; The root cause is that the product of the BTC and the coefficient triggers an
+; overflow.
+define void @strongsiv_const_ovfl(ptr %A) {
+; CHECK-LABEL: 'strongsiv_const_ovfl'
+; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
+; CHECK-NEXT:    da analyze - none!
+; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-NEXT:    da analyze - none!
+; CHECK-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-NEXT:    da analyze - none!
+;
+; CHECK-STRONG-SIV-LABEL: 'strongsiv_const_ovfl'
+; CHECK-STRONG-SIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
+; CHECK-STRONG-SIV-NEXT:    da analyze - none!
+; CHECK-STRONG-SIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-STRONG-SIV-NEXT:    da analyze - none!
+; CHECK-STRONG-SIV-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-STRONG-SIV-NEXT:    da analyze - none!
+;
+entry:
+  br label %loop.header
+
+loop.header:
+  %i = phi i64 [ 0, %entry ], [ %i.inc, %loop.latch ]
+  %offset.0 = phi i64 [ -2, %entry ], [ %offset.0.next, %loop.latch ]
+  %offset.1 = phi i64 [ -4, %entry ], [ %offset.1.next, %loop.latch ]
+  %ec = icmp eq i64 %i, 4611686018427387904
+  br i1 %ec, label %exit, label %loop.body
+
+loop.body:
+  %cond.0 = icmp sge i64 %offset.0, 0
+  %cond.1 = icmp sge i64 %offset.1, 0
+  br i1 %cond.0, label %if.then.0, label %loop.middle
+
+if.then.0:
+  %gep.0 = getelementptr inbounds i8, ptr %A, i64 %offset.0
+  store i8 1, ptr %gep.0
+  br label %loop.middle
+
+loop.middle:
+  br i1 %cond.1, label %if.then.1, label %loop.latch
+
+if.then.1:
+  %gep.1 = getelementptr inbounds i8, ptr %A, i64 %offset.1
+  store i8 2, ptr %gep.1
+  br label %loop.latch
+
+loop.latch:
+  %i.inc = add nuw nsw i64 %i, 1
+  %offset.0.next = add nsw i64 %offset.0, 2
+  %offset.1.next = add nsw i64 %offset.1, 2
+  br label %loop.header
+
+exit:
+  ret void
+}
diff --git a/llvm/test/Analysis/DependenceAnalysis/symbolic-rdiv-overflow.ll b/llvm/test/Analysis/DependenceAnalysis/symbolic-rdiv-overflow.ll
new file mode 100644
index 0000000000000..f22553f9931a2
--- /dev/null
+++ b/llvm/test/Analysis/DependenceAnalysis/symbolic-rdiv-overflow.ll
@@ -0,0 +1,128 @@
+; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py UTC_ARGS: --version 6
+; RUN: opt < %s -disable-output "-passes=print<da>" 2>&1 | FileCheck %s
+; RUN: opt < %s -disable-output "-passes=print<da>" -da-enable-dependence-test=symbolic-rdiv 2>&1 \
+; RUN:     | FileCheck %s --check-prefix=CHECK-SYMBOLIC-RDIV
+
+; offset = -2;
+; for (i = 0; i < (1LL << 62); i++, offset += 2) {
+;   if (0 <= offset0)
+;     A[offset0] = 1;
+;   A[i] = 2;
+; }
+;
+; FIXME: DependenceAnalysis currently detects no dependency between the two
+; stores, but it does exist.
+; The root cause is that the product of the BTC and the coefficient triggers an
+; overflow.
+define void @symbolicrdiv_prod_ovfl(ptr %A) {
+; CHECK-LABEL: 'symbolicrdiv_prod_ovfl'
+; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
+; CHECK-NEXT:    da analyze - none!
+; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-NEXT:    da analyze - none!
+; CHECK-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-NEXT:    da analyze - none!
+;
+; CHECK-SYMBOLIC-RDIV-LABEL: 'symbolicrdiv_prod_ovfl'
+; CHECK-SYMBOLIC-RDIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
+; CHECK-SYMBOLIC-RDIV-NEXT:    da analyze - none!
+; CHECK-SYMBOLIC-RDIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-SYMBOLIC-RDIV-NEXT:    da analyze - none!
+; CHECK-SYMBOLIC-RDIV-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-SYMBOLIC-RDIV-NEXT:    da analyze - consistent output [*]!
+;
+entry:
+  br label %loop.header
+
+loop.header:
+  %i = phi i64 [ 0, %entry ], [ %i.inc, %loop.latch ]
+  %offset = phi i64 [ -2, %entry ], [ %offset.next, %loop.latch ]
+  %ec = icmp eq i64 %i, 4611686018427387904
+  br i1 %ec, label %exit, label %loop.body
+
+loop.body:
+  %cond = icmp sge i64 %offset, 0
+  br i1 %cond, label %if.then, label %loop.latch
+
+if.then:
+  %gep.0 = getelementptr inbounds i8, ptr %A, i64 %offset
+  store i8 1, ptr %gep.0
+  br label %loop.latch
+
+loop.latch:
+  %gep.1 = getelementptr inbounds i8, ptr %A, i64 %i
+  store i8 2, ptr %gep.1
+  %i.inc = add nuw nsw i64 %i, 1
+  %offset.next = add nsw i64 %offset, 2
+  br label %loop.header
+
+exit:
+  ret void
+}
+
+; offset0 = -4611686018427387904  // -2^62
+; offset1 =  4611686018427387904  // 2^62
+; for (i = 0; i < (1LL << 62) - 100; i++) {
+;   if (0 <= offset0)
+;     A[offset0] = 1;
+;   if (0 <= offset1)
+;     A[offset1] = 2;
+;   offset0 += 2;
+;   offset1 -= 1;
+; }
+;
+; FIXME: DependenceAnalysis currently detects no dependency between the two
+; stores, but it does exist.
+; The root cause is that the calculation of the differenct between the two
+; constants (-2^62 and 2^62) triggers an overflow.
+define void @symbolicrdiv_delta_ovfl(ptr %A) {
+; CHECK-LABEL: 'symbolicrdiv_delta_ovfl'
+; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
+; CHECK-NEXT:    da analyze - none!
+; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-NEXT:    da analyze - none!
+; CHECK-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-NEXT:    da analyze - none!
+;
+; CHECK-SYMBOLIC-RDIV-LABEL: 'symbolicrdiv_delta_ovfl'
+; CHECK-SYMBOLIC-RDIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
+; CHECK-SYMBOLIC-RDIV-NEXT:    da analyze - consistent output [*]!
+; CHECK-SYMBOLIC-RDIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-SYMBOLIC-RDIV-NEXT:    da analyze - none!
+; CHECK-SYMBOLIC-RDIV-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-SYMBOLIC-RDIV-NEXT:    da analyze - consistent output [*]!
+;
+entry:
+  br label %loop.header
+
+loop.header:
+  %i = phi i64 [ 0, %entry ], [ %i.inc, %loop.latch ]
+  %offset.0 = phi i64 [ -4611686018427387904, %entry ], [ %offset.0.next, %loop.latch ]
+  %offset.1 = phi i64 [ 4611686018427387904, %entry ], [ %offset.1.next, %loop.latch ]
+  %cond.0 = icmp sge i64 %offset.0, 0
+  %cond.1 = icmp sge i64 %offset.1, 0
+  br i1 %cond.0, label %if.then.0, label %loop.middle
+
+if.then.0:
+  %gep.0 = getelementptr inbounds i8, ptr %A, i64 %offset.0
+  store i8 1, ptr %gep.0
+  br label %loop.middle
+
+loop.middle:
+  br i1 %cond.1, label %if.then.1, label %loop.latch
+
+if.then.1:
+  %gep.1 = getelementptr inbounds i8, ptr %A, i64 %offset.1
+  store i8 2, ptr %gep.1
+  br label %loop.latch
+
+loop.latch:
+  %i.inc = add nuw nsw i64 %i, 1
+  %offset.0.next = add nsw i64 %offset.0, 2
+  %offset.1.next = sub nsw i64 %offset.1, 1
+  %ec = icmp eq i64 %i.inc, 4611686018427387804 ; 2^62 - 100
+  br i1 %ec, label %exit, label %loop.header
+
+exit:
+  ret void
+}
diff --git a/llvm/test/Analysis/DependenceAnalysis/weak-crossing-siv-overflow.ll b/llvm/test/Analysis/DependenceAnalysis/weak-crossing-siv-overflow.ll
new file mode 100644
index 0000000000000..59412d8381d68
--- /dev/null
+++ b/llvm/test/Analysis/DependenceAnalysis/weak-crossing-siv-overflow.ll
@@ -0,0 +1,122 @@
+; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py UTC_ARGS: --version 6
+; RUN: opt < %s -disable-output "-passes=print<da>" 2>&1 | FileCheck %s
+; RUN: opt < %s -disable-output "-passes=print<da>" -da-enable-dependence-test=weak-crossing-siv 2>&1 \
+; RUN:     | FileCheck %s --check-prefix=CHECK-WEAK-CROSSING-SIV
+
+; max_i = INT64_MAX/3  // 3074457345618258602
+; for (long long i = 0; i <= max_i; i++) {
+;   A[-3*i + INT64_MAX] = 0;
+;   if (i)
+;     A[3*i - 2] = 1;
+; }
+;
+; FIXME: DependencyAnalsysis currently detects no dependency between
+; `A[-3*i + INT64_MAX]` and `A[3*i - 2]`, but it does exist. For example,
+;
+;  memory location  | -3*i + INT64_MAX | 3*i - 2
+; ------------------|------------------|-----------
+;  A[1]             | i = max_i        | i = 1
+;  A[INT64_MAX - 3] | i = 1            | i = max_i
+;
+; The root cause is that the calculation of the differenct between the two
+; constants (INT64_MAX and -2) triggers an overflow.
+
+define void @weakcorssing_delta_ovfl(ptr %A) {
+; CHECK-LABEL: 'weakcorssing_delta_ovfl'
+; CHECK-NEXT:  Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 0, ptr %idx.0, align 1
+; CHECK-NEXT:    da analyze - none!
+; CHECK-NEXT:  Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 1, ptr %idx.1, align 1
+; CHECK-NEXT:    da analyze - none!
+; CHECK-NEXT:  Src: store i8 1, ptr %idx.1, align 1 --> Dst: store i8 1, ptr %idx.1, align 1
+; CHECK-NEXT:    da analyze - none!
+;
+; CHECK-WEAK-CROSSING-SIV-LABEL: 'weakcorssing_delta_ovfl'
+; CHECK-WEAK-CROSSING-SIV-NEXT:  Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 0, ptr %idx.0, align 1
+; CHECK-WEAK-CROSSING-SIV-NEXT:    da analyze - consistent output [*]!
+; CHECK-WEAK-CROSSING-SIV-NEXT:  Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 1, ptr %idx.1, align 1
+; CHECK-WEAK-CROSSING-SIV-NEXT:    da analyze - none!
+; CHECK-WEAK-CROSSING-SIV-NEXT:  Src: store i8 1, ptr %idx.1, align 1 --> Dst: store i8 1, ptr %idx.1, align 1
+; CHECK-WEAK-CROSSING-SIV-NEXT:    da analyze - consistent output [*]!
+;
+entry:
+  br label %loop.header
+
+loop.header:
+  %i = phi i64 [ 0, %entry ], [ %i.inc, %loop.latch ]
+  %subscript.0 = phi i64 [ 9223372036854775807, %entry ], [ %subscript.0.next, %loop.latch ]
+  %subscript.1 = phi i64 [ -2, %entry ], [ %subscript.1.next, %loop.latch ]
+  %idx.0 = getelementptr inbounds i8, ptr %A, i64 %subscript.0
+  store i8 0, ptr %idx.0
+  %cond.store = icmp ne i64 %i, 0
+  br i1 %cond.store, label %if.store, label %loop.latch
+
+if.store:
+  %idx.1 = getelementptr inbounds i8, ptr %A, i64 %subscript.1
+  store i8 1, ptr %idx.1
+  br label %loop.latch
+
+loop.latch:
+  %i.inc = add nuw nsw i64 %i, 1
+  %subscript.0.next = add nsw i64 %subscript.0, -3
+  %subscript.1.next = add nsw i64 %subscript.1, 3
+  %ec = icmp sgt i64 %i.inc, 3074457345618258602
+  br i1 %ec, label %exit, label %loop.header
+
+exit:
+  ret void
+}
+
+; max_i = INT64_MAX/3  // 3074457345618258602
+; for (long long i = 0; i <= max_i; i++) {
+;   A[-3*i + INT64_MAX] = 0;
+;   A[3*i + 1] = 1;
+; }
+;
+; FIXME: DependencyAnalsysis currently detects no dependency between
+; `A[-3*i + INT64_MAX]` and `A[3*i - 2]`, but it does exist. For example,
+;
+;  memory location  | -3*i + INT64_MAX | 3*i + 1
+; ------------------|------------------|--------------
+;  A[1]             | i = max_i        | i = 0
+;  A[INT64_MAX - 3] | i = 1            | i = max_i - 1
+;
+; The root cause is that the product of the BTC, the coefficient, and 2
+; triggers an overflow.
+;
+define void @weakcorssing_prod_ovfl(ptr %A) {
+; CHECK-LABEL: 'weakcorssing_prod_ovfl'
+; CHECK-NEXT:  Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 0, ptr %idx.0, align 1
+; CHECK-NEXT:    da analyze - none!
+; CHECK-NEXT:  Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 1, ptr %idx.1, align 1
+; CHECK-NEXT:    da analyze - none!
+; CHECK-NEXT:  Src: store i8 1, ptr %idx.1, align 1 --> Dst: store i8 1, ptr %idx.1, align 1
+; CHECK-NEXT:    da analyze - none!
+;
+; CHECK-WEAK-CROSSING-SIV-LABEL: 'weakcorssing_prod_ovfl'
+; CHECK-WEAK-CROSSING-SIV-NEXT:  Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 0, ptr %idx.0, align 1
+; CHECK-WEAK-CROSSING-SIV-NEXT:    da analyze - consistent output [*]!
+; CHECK-WEAK-CROSSING-SIV-NEXT:  Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 1, ptr %idx.1, align 1
+; CHECK-WEAK-CROSSING-SIV-NEXT:    da analyze - none!
+; CHECK-WEAK-CROSSING-SIV-NEXT:  Src: store i8 1, ptr %idx.1, align 1 --> Dst: store i8 1, ptr %idx.1, align 1
+; CHECK-WEAK-CROSSING-SIV-NEXT:    da analyze - consistent output [*]!
+;
+entry:
+  br label %loop
+
+loop:
+  %i = phi i64 [ 0, %entry ], [ %i.inc, %loop ]
+  %subscript.0 = phi i64 [ 9223372036854775807, %entry ], [ %subscript.0.next, %loop ]
+  %subscript.1 = phi i64 [ 1, %entry ], [ %subscript.1.next, %loop ]
+  %idx.0 = getelementptr inbounds i8, ptr %A, i64 %subscript.0
+  %idx.1 = getelementptr inbounds i8, ptr %A, i64 %subscript.1
+  store i8 0, ptr %idx.0
+  store i8 1, ptr %idx.1
+  %i.inc = add nuw nsw i64 %i, 1
+  %subscript.0.next = add nsw i64 %subscript.0, -3
+  %subscript.1.next = add nsw i64 %subscript.1, 3
+  %ec = icmp sgt i64 %i.inc, 3074457345618258602
+  br i1 %ec, label %exit, label %loop
+
+exit:
+  ret void
+}
diff --git a/llvm/test/Analysis/DependenceAnalysis/weak-zero-siv-overflow.ll b/llvm/test/Analysis/DependenceAnalysis/weak-zero-siv-overflow.ll
new file mode 100644
index 0000000000000..0e5deb610bd61
--- /dev/null
+++ b/llvm/test/Analysis/DependenceAnalysis/weak-zero-siv-overflow.ll
@@ -0,0 +1,121 @@
+; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py UTC_ARGS: --version 6
+; RUN: opt < %s -disable-output "-passes=print<da>" 2>&1 | FileCheck %s
+; RUN: opt < %s -disable-output "-passes=print<da>" -da-enable-dependence-test=weak-zero-siv 2>&1 \
+; RUN:     | FileCheck %s --check-prefix=CHECK-WEAK-ZERO-SIV
+
+; offset = -2;
+; for (i = 0; i < (1LL << 62); i++, offset += 2) {
+;   if (0 <= offset)
+;     A[offset] = 1;
+;   A[2] = 2;
+; }
+;
+; FIXME: DependenceAnalysis currently detects no dependency between the two
+; stores, but it does exist. The root cause is that the product of the BTC and
+; the coefficient triggers an overflow.
+;
+define void @weakzero_dst_siv_prod_ovfl(ptr %A) {
+; CHECK-LABEL: 'weakzero_dst_siv_prod_ovfl'
+; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
+; CHECK-NEXT:    da analyze - none!
+; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-NEXT:    da analyze - none!
+; CHECK-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-NEXT:    da analyze - consistent output [S]!
+;
+; CHECK-WEAK-ZERO-SIV-LABEL: 'weakzero_dst_siv_prod_ovfl'
+; CHECK-WEAK-ZERO-SIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
+; CHECK-WEAK-ZERO-SIV-NEXT:    da analyze - consistent output [*]!
+; CHECK-WEAK-ZERO-SIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-WEAK-ZERO-SIV-NEXT:    da analyze - none!
+; CHECK-WEAK-ZERO-SIV-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-WEAK-ZERO-SIV-NEXT:    da analyze - consistent output [S]!
+;
+entry:
+  br label %loop.header
+
+loop.header:
+  %i = phi i64 [ 0, %entry ], [ %i.inc, %loop.latch ]
+  %offset = phi i64 [ -2, %entry ], [ %offset.next, %loop.latch ]
+  %ec = icmp eq i64 %i, 4611686018427387904
+  br i1 %ec, label %exit, label %loop.body
+
+loop.body:
+  %cond = icmp sge i64 %offset, 0
+  br i1 %cond, label %if.then, label %loop.latch
+
+if.then:
+  %gep.0 = getelementptr inbounds i8, ptr %A, i64 %offset
+  store i8 1, ptr %gep.0
+  br label %loop.latch
+
+loop.latch:
+  %gep.1 = getelementptr inbounds i8, ptr %A, i64 2
+  store i8 2, ptr %gep.1
+  %i.inc = add nuw nsw i64 %i, 1
+  %offset.next = add nsw i64 %offset, 2
+  br label %loop.header
+
+exit:
+  ret void
+}
+
+; offset = -1;
+; for (i = 0; i < n; i++, offset += 2) {
+;   if (0 <= offset)
+;     A[offset] = 1;
+;   A[INT64_MAX] = 2;
+; }
+;
+; FIXME: DependenceAnalysis currently detects no dependency between the two
+; stores, but it does exist. When `%n` is 2^62, the value of `%offset` will be
+; the same as INT64_MAX at the last iteration.
+; The root cause is that the calculation of the differenct between the two
+; constants (INT64_MAX and -1) triggers an overflow.
+;
+define void @weakzero_dst_siv_delta_ovfl(ptr %A, i64 %n) {
+; CHECK-LABEL: 'weakzero_dst_siv_delta_ovfl'
+; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
+; CHECK-NEXT:    da analyze - none!
+; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-NEXT:    da analyze - none!
+; CHECK-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-NEXT:    da analyze - consistent output [S]!
+;
+; CHECK-WEAK-ZERO-SIV-LABEL: 'weakzero_dst_siv_delta_ovfl'
+; CHECK-WEAK-ZERO-SIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
+; CHECK-WEAK-ZERO-SIV-NEXT:    da analyze - consistent output [*]!
+; CHECK-WEAK-ZERO-SIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-WEAK-ZERO-SIV-NEXT:    da analyze - none!
+; CHECK-WEAK-ZERO-SIV-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-WEAK-ZERO-SIV-NEXT:    da analyze - consistent output [S]!
+;
+entry:
+  %guard = icmp sgt i64 %n, 0
+  br i1 %guard, label %loop.header, label %exit
+
+loop.header:
+  %i = phi i64 [ 0, %entry ], [ %i.inc, %loop.latch ]
+  %offset = phi i64 [ -2, %entry ], [ %offset.next, %loop.latch ]
+  %ec = icmp eq i64 %i, %n
+  br i1 %ec, label %exit, label %loop.body
+
+loop.body:
+  %cond = icmp sge i64 %offset, 0
+  br i1 %cond, label %if.then, label %loop.latch
+
+if.then:
+  %gep.0 = getelementptr inbounds i8, ptr %A, i64 %offset
+  store i8 1, ptr %gep.0
+  br label %loop.latch
+
+loop.latch:
+  %gep.1 = getelementptr inbounds i8, ptr %A, i64 9223372036854775807
+  store i8 2, ptr %gep.1
+  %i.inc = add nuw nsw i64 %i, 1
+  %offset.next = add nsw i64 %offset, 2
+  br label %loop.header
+
+exit:
+  ret void
+}

>From 7444b19e7d9d1feb82504368ada8c6b00f91f8b4 Mon Sep 17 00:00:00 2001
From: Ryotaro Kasuga <kasuga.ryotaro at fujitsu.com>
Date: Tue, 28 Oct 2025 07:52:03 +0000
Subject: [PATCH 2/4] use --check-prefixes

---
 .../DependenceAnalysis/gcd-miv-overflow.ll    | 21 ++++++-----
 .../DependenceAnalysis/strong-siv-overflow.ll | 16 ++++-----
 .../symbolic-rdiv-overflow.ll                 | 35 ++++++++++---------
 .../weak-crossing-siv-overflow.ll             | 35 ++++++++++---------
 .../weak-zero-siv-overflow.ll                 | 35 ++++++++++---------
 5 files changed, 75 insertions(+), 67 deletions(-)

diff --git a/llvm/test/Analysis/DependenceAnalysis/gcd-miv-overflow.ll b/llvm/test/Analysis/DependenceAnalysis/gcd-miv-overflow.ll
index 724b347b56f3a..86c50c00251f5 100644
--- a/llvm/test/Analysis/DependenceAnalysis/gcd-miv-overflow.ll
+++ b/llvm/test/Analysis/DependenceAnalysis/gcd-miv-overflow.ll
@@ -1,7 +1,8 @@
 ; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py UTC_ARGS: --version 6
-; RUN: opt < %s -disable-output "-passes=print<da>" 2>&1 | FileCheck %s
+; RUN: opt < %s -disable-output "-passes=print<da>" 2>&1 \
+; RUN:     | FileCheck %s --check-prefixes=CHECK,CHECK-ALL
 ; RUN: opt < %s -disable-output "-passes=print<da>" -da-enable-dependence-test=gcd-miv 2>&1 \
-; RUN:     | FileCheck %s --check-prefix=CHECK-GCD-MIV
+; RUN:     | FileCheck %s --check-prefixes=CHECK,CHECK-GCD-MIV
 
 ; offset0 = 4;
 ; offset1 = 0;
@@ -24,13 +25,13 @@
 ; sense, which isn't necessarily true due to overflow.
 ;
 define void @gcdmiv_coef_ovfl(ptr %A, i64 %m) {
-; CHECK-LABEL: 'gcdmiv_coef_ovfl'
-; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
-; CHECK-NEXT:    da analyze - none!
-; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
-; CHECK-NEXT:    da analyze - none!
-; CHECK-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
-; CHECK-NEXT:    da analyze - none!
+; CHECK-ALL-LABEL: 'gcdmiv_coef_ovfl'
+; CHECK-ALL-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
+; CHECK-ALL-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
+; CHECK-ALL-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
 ;
 ; CHECK-GCD-MIV-LABEL: 'gcdmiv_coef_ovfl'
 ; CHECK-GCD-MIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
@@ -61,3 +62,5 @@ loop:
 exit:
   ret void
 }
+;; NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
+; CHECK: {{.*}}
diff --git a/llvm/test/Analysis/DependenceAnalysis/strong-siv-overflow.ll b/llvm/test/Analysis/DependenceAnalysis/strong-siv-overflow.ll
index 559f4858612e5..88a9dab99f9cc 100644
--- a/llvm/test/Analysis/DependenceAnalysis/strong-siv-overflow.ll
+++ b/llvm/test/Analysis/DependenceAnalysis/strong-siv-overflow.ll
@@ -1,7 +1,8 @@
 ; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py UTC_ARGS: --version 6
-; RUN: opt < %s -disable-output "-passes=print<da>" 2>&1 | FileCheck %s
+; RUN: opt < %s -disable-output "-passes=print<da>" 2>&1 \
+; RUN:     | FileCheck %s --check-prefixes=CHECK,CHECK-ALL
 ; RUN: opt < %s -disable-output "-passes=print<da>" -da-enable-dependence-test=strong-siv 2>&1 \
-; RUN:     | FileCheck %s --check-prefix=CHECK-STRONG-SIV
+; RUN:     | FileCheck %s --check-prefixes=CHECK,CHECK-STRONG-SIV
 
 ; offset0 = -2;
 ; offset1 = -4;
@@ -25,14 +26,6 @@ define void @strongsiv_const_ovfl(ptr %A) {
 ; CHECK-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
 ; CHECK-NEXT:    da analyze - none!
 ;
-; CHECK-STRONG-SIV-LABEL: 'strongsiv_const_ovfl'
-; CHECK-STRONG-SIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
-; CHECK-STRONG-SIV-NEXT:    da analyze - none!
-; CHECK-STRONG-SIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
-; CHECK-STRONG-SIV-NEXT:    da analyze - none!
-; CHECK-STRONG-SIV-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
-; CHECK-STRONG-SIV-NEXT:    da analyze - none!
-;
 entry:
   br label %loop.header
 
@@ -70,3 +63,6 @@ loop.latch:
 exit:
   ret void
 }
+;; NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
+; CHECK-ALL: {{.*}}
+; CHECK-STRONG-SIV: {{.*}}
diff --git a/llvm/test/Analysis/DependenceAnalysis/symbolic-rdiv-overflow.ll b/llvm/test/Analysis/DependenceAnalysis/symbolic-rdiv-overflow.ll
index f22553f9931a2..9a019e988b418 100644
--- a/llvm/test/Analysis/DependenceAnalysis/symbolic-rdiv-overflow.ll
+++ b/llvm/test/Analysis/DependenceAnalysis/symbolic-rdiv-overflow.ll
@@ -1,7 +1,8 @@
 ; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py UTC_ARGS: --version 6
-; RUN: opt < %s -disable-output "-passes=print<da>" 2>&1 | FileCheck %s
+; RUN: opt < %s -disable-output "-passes=print<da>" 2>&1 \
+; RUN:     | FileCheck %s --check-prefixes=CHECK,CHECK-ALL
 ; RUN: opt < %s -disable-output "-passes=print<da>" -da-enable-dependence-test=symbolic-rdiv 2>&1 \
-; RUN:     | FileCheck %s --check-prefix=CHECK-SYMBOLIC-RDIV
+; RUN:     | FileCheck %s --check-prefixes=CHECK,CHECK-SYMBOLIC-RDIV
 
 ; offset = -2;
 ; for (i = 0; i < (1LL << 62); i++, offset += 2) {
@@ -15,13 +16,13 @@
 ; The root cause is that the product of the BTC and the coefficient triggers an
 ; overflow.
 define void @symbolicrdiv_prod_ovfl(ptr %A) {
-; CHECK-LABEL: 'symbolicrdiv_prod_ovfl'
-; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
-; CHECK-NEXT:    da analyze - none!
-; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
-; CHECK-NEXT:    da analyze - none!
-; CHECK-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
-; CHECK-NEXT:    da analyze - none!
+; CHECK-ALL-LABEL: 'symbolicrdiv_prod_ovfl'
+; CHECK-ALL-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
+; CHECK-ALL-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
+; CHECK-ALL-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
 ;
 ; CHECK-SYMBOLIC-RDIV-LABEL: 'symbolicrdiv_prod_ovfl'
 ; CHECK-SYMBOLIC-RDIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
@@ -76,13 +77,13 @@ exit:
 ; The root cause is that the calculation of the differenct between the two
 ; constants (-2^62 and 2^62) triggers an overflow.
 define void @symbolicrdiv_delta_ovfl(ptr %A) {
-; CHECK-LABEL: 'symbolicrdiv_delta_ovfl'
-; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
-; CHECK-NEXT:    da analyze - none!
-; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
-; CHECK-NEXT:    da analyze - none!
-; CHECK-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
-; CHECK-NEXT:    da analyze - none!
+; CHECK-ALL-LABEL: 'symbolicrdiv_delta_ovfl'
+; CHECK-ALL-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
+; CHECK-ALL-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
+; CHECK-ALL-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
 ;
 ; CHECK-SYMBOLIC-RDIV-LABEL: 'symbolicrdiv_delta_ovfl'
 ; CHECK-SYMBOLIC-RDIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
@@ -126,3 +127,5 @@ loop.latch:
 exit:
   ret void
 }
+;; NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
+; CHECK: {{.*}}
diff --git a/llvm/test/Analysis/DependenceAnalysis/weak-crossing-siv-overflow.ll b/llvm/test/Analysis/DependenceAnalysis/weak-crossing-siv-overflow.ll
index 59412d8381d68..d04442f804700 100644
--- a/llvm/test/Analysis/DependenceAnalysis/weak-crossing-siv-overflow.ll
+++ b/llvm/test/Analysis/DependenceAnalysis/weak-crossing-siv-overflow.ll
@@ -1,7 +1,8 @@
 ; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py UTC_ARGS: --version 6
-; RUN: opt < %s -disable-output "-passes=print<da>" 2>&1 | FileCheck %s
+; RUN: opt < %s -disable-output "-passes=print<da>" 2>&1 \
+; RUN:     | FileCheck %s --check-prefixes=CHECK,CHECK-ALL
 ; RUN: opt < %s -disable-output "-passes=print<da>" -da-enable-dependence-test=weak-crossing-siv 2>&1 \
-; RUN:     | FileCheck %s --check-prefix=CHECK-WEAK-CROSSING-SIV
+; RUN:     | FileCheck %s --check-prefixes=CHECK,CHECK-WEAK-CROSSING-SIV
 
 ; max_i = INT64_MAX/3  // 3074457345618258602
 ; for (long long i = 0; i <= max_i; i++) {
@@ -22,13 +23,13 @@
 ; constants (INT64_MAX and -2) triggers an overflow.
 
 define void @weakcorssing_delta_ovfl(ptr %A) {
-; CHECK-LABEL: 'weakcorssing_delta_ovfl'
-; CHECK-NEXT:  Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 0, ptr %idx.0, align 1
-; CHECK-NEXT:    da analyze - none!
-; CHECK-NEXT:  Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 1, ptr %idx.1, align 1
-; CHECK-NEXT:    da analyze - none!
-; CHECK-NEXT:  Src: store i8 1, ptr %idx.1, align 1 --> Dst: store i8 1, ptr %idx.1, align 1
-; CHECK-NEXT:    da analyze - none!
+; CHECK-ALL-LABEL: 'weakcorssing_delta_ovfl'
+; CHECK-ALL-NEXT:  Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 0, ptr %idx.0, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
+; CHECK-ALL-NEXT:  Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 1, ptr %idx.1, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
+; CHECK-ALL-NEXT:  Src: store i8 1, ptr %idx.1, align 1 --> Dst: store i8 1, ptr %idx.1, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
 ;
 ; CHECK-WEAK-CROSSING-SIV-LABEL: 'weakcorssing_delta_ovfl'
 ; CHECK-WEAK-CROSSING-SIV-NEXT:  Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 0, ptr %idx.0, align 1
@@ -84,13 +85,13 @@ exit:
 ; triggers an overflow.
 ;
 define void @weakcorssing_prod_ovfl(ptr %A) {
-; CHECK-LABEL: 'weakcorssing_prod_ovfl'
-; CHECK-NEXT:  Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 0, ptr %idx.0, align 1
-; CHECK-NEXT:    da analyze - none!
-; CHECK-NEXT:  Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 1, ptr %idx.1, align 1
-; CHECK-NEXT:    da analyze - none!
-; CHECK-NEXT:  Src: store i8 1, ptr %idx.1, align 1 --> Dst: store i8 1, ptr %idx.1, align 1
-; CHECK-NEXT:    da analyze - none!
+; CHECK-ALL-LABEL: 'weakcorssing_prod_ovfl'
+; CHECK-ALL-NEXT:  Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 0, ptr %idx.0, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
+; CHECK-ALL-NEXT:  Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 1, ptr %idx.1, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
+; CHECK-ALL-NEXT:  Src: store i8 1, ptr %idx.1, align 1 --> Dst: store i8 1, ptr %idx.1, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
 ;
 ; CHECK-WEAK-CROSSING-SIV-LABEL: 'weakcorssing_prod_ovfl'
 ; CHECK-WEAK-CROSSING-SIV-NEXT:  Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 0, ptr %idx.0, align 1
@@ -120,3 +121,5 @@ loop:
 exit:
   ret void
 }
+;; NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
+; CHECK: {{.*}}
diff --git a/llvm/test/Analysis/DependenceAnalysis/weak-zero-siv-overflow.ll b/llvm/test/Analysis/DependenceAnalysis/weak-zero-siv-overflow.ll
index 0e5deb610bd61..2ccd4a406e212 100644
--- a/llvm/test/Analysis/DependenceAnalysis/weak-zero-siv-overflow.ll
+++ b/llvm/test/Analysis/DependenceAnalysis/weak-zero-siv-overflow.ll
@@ -1,7 +1,8 @@
 ; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py UTC_ARGS: --version 6
-; RUN: opt < %s -disable-output "-passes=print<da>" 2>&1 | FileCheck %s
+; RUN: opt < %s -disable-output "-passes=print<da>" 2>&1 \
+; RUN:     | FileCheck %s --check-prefixes=CHECK,CHECK-ALL
 ; RUN: opt < %s -disable-output "-passes=print<da>" -da-enable-dependence-test=weak-zero-siv 2>&1 \
-; RUN:     | FileCheck %s --check-prefix=CHECK-WEAK-ZERO-SIV
+; RUN:     | FileCheck %s --check-prefixes=CHECK,CHECK-WEAK-ZERO-SIV
 
 ; offset = -2;
 ; for (i = 0; i < (1LL << 62); i++, offset += 2) {
@@ -15,13 +16,13 @@
 ; the coefficient triggers an overflow.
 ;
 define void @weakzero_dst_siv_prod_ovfl(ptr %A) {
-; CHECK-LABEL: 'weakzero_dst_siv_prod_ovfl'
-; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
-; CHECK-NEXT:    da analyze - none!
-; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
-; CHECK-NEXT:    da analyze - none!
-; CHECK-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
-; CHECK-NEXT:    da analyze - consistent output [S]!
+; CHECK-ALL-LABEL: 'weakzero_dst_siv_prod_ovfl'
+; CHECK-ALL-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
+; CHECK-ALL-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
+; CHECK-ALL-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-ALL-NEXT:    da analyze - consistent output [S]!
 ;
 ; CHECK-WEAK-ZERO-SIV-LABEL: 'weakzero_dst_siv_prod_ovfl'
 ; CHECK-WEAK-ZERO-SIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
@@ -74,13 +75,13 @@ exit:
 ; constants (INT64_MAX and -1) triggers an overflow.
 ;
 define void @weakzero_dst_siv_delta_ovfl(ptr %A, i64 %n) {
-; CHECK-LABEL: 'weakzero_dst_siv_delta_ovfl'
-; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
-; CHECK-NEXT:    da analyze - none!
-; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
-; CHECK-NEXT:    da analyze - none!
-; CHECK-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
-; CHECK-NEXT:    da analyze - consistent output [S]!
+; CHECK-ALL-LABEL: 'weakzero_dst_siv_delta_ovfl'
+; CHECK-ALL-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
+; CHECK-ALL-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-ALL-NEXT:    da analyze - none!
+; CHECK-ALL-NEXT:  Src: store i8 2, ptr %gep.1, align 1 --> Dst: store i8 2, ptr %gep.1, align 1
+; CHECK-ALL-NEXT:    da analyze - consistent output [S]!
 ;
 ; CHECK-WEAK-ZERO-SIV-LABEL: 'weakzero_dst_siv_delta_ovfl'
 ; CHECK-WEAK-ZERO-SIV-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
@@ -119,3 +120,5 @@ loop.latch:
 exit:
   ret void
 }
+;; NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
+; CHECK: {{.*}}

>From ae260d303d66ac80c7130f684918d978e9b184bf Mon Sep 17 00:00:00 2001
From: Ryotaro Kasuga <kasuga.ryotaro at fujitsu.com>
Date: Wed, 29 Oct 2025 09:57:18 +0000
Subject: [PATCH 3/4] address review comments

---
 .../DependenceAnalysis/gcd-miv-overflow.ll    |  4 +--
 .../DependenceAnalysis/strong-siv-overflow.ll | 20 ++++++-------
 .../symbolic-rdiv-overflow.ll                 | 28 +++++++++++--------
 .../weak-crossing-siv-overflow.ll             | 20 ++++++-------
 .../weak-zero-siv-overflow.ll                 | 20 ++++++-------
 5 files changed, 48 insertions(+), 44 deletions(-)

diff --git a/llvm/test/Analysis/DependenceAnalysis/gcd-miv-overflow.ll b/llvm/test/Analysis/DependenceAnalysis/gcd-miv-overflow.ll
index 86c50c00251f5..43f66dd7d0974 100644
--- a/llvm/test/Analysis/DependenceAnalysis/gcd-miv-overflow.ll
+++ b/llvm/test/Analysis/DependenceAnalysis/gcd-miv-overflow.ll
@@ -21,8 +21,8 @@
 ;   - A[offset0] : A[4], A[5], A[6], ...
 ;   - A[offset1] : A[0], A[3], A[6], ...
 ;
-; The root cause is that DA assumes `3*m` begin a multiple of 3 in mathematical
-; sense, which isn't necessarily true due to overflow.
+; The root cause is that DA interprets `3*m` in non-modular arithmetic, which
+; isn't necessarily true due to overflow.
 ;
 define void @gcdmiv_coef_ovfl(ptr %A, i64 %m) {
 ; CHECK-ALL-LABEL: 'gcdmiv_coef_ovfl'
diff --git a/llvm/test/Analysis/DependenceAnalysis/strong-siv-overflow.ll b/llvm/test/Analysis/DependenceAnalysis/strong-siv-overflow.ll
index 88a9dab99f9cc..bf0fafcbfd6c9 100644
--- a/llvm/test/Analysis/DependenceAnalysis/strong-siv-overflow.ll
+++ b/llvm/test/Analysis/DependenceAnalysis/strong-siv-overflow.ll
@@ -4,19 +4,19 @@
 ; RUN: opt < %s -disable-output "-passes=print<da>" -da-enable-dependence-test=strong-siv 2>&1 \
 ; RUN:     | FileCheck %s --check-prefixes=CHECK,CHECK-STRONG-SIV
 
-; offset0 = -2;
-; offset1 = -4;
-; for (i = 0; i < (1LL << 62); i++, offset0 += 2, offset1 += 2) {
-;   if (0 <= offset0)
-;     A[offset0] = 1;
-;   if (0 <= offset1)
-;     A[offset1] = 2;
+; for (i = 0; i < (1LL << 62); i++) {
+;   if (0 <= 2*i - 2)
+;     A[2*i - 2] = 1;
+;
+;   if (0 <= 2*i - 4)
+;     A[2*i - 4] = 2;
 ; }
 ;
 ; FIXME: DependenceAnalysis currently detects no dependency between the two
-; stores, but it does exist.
-; The root cause is that the product of the BTC and the coefficient triggers an
-; overflow.
+; stores, but it does exist. For example, each store will access A[0] when i
+; is 1 and 2 respectively.
+; The root cause is that the product of the BTC and the coefficient
+; ((1LL << 62) - 1 and 2) overflows in a signed sense.
 define void @strongsiv_const_ovfl(ptr %A) {
 ; CHECK-LABEL: 'strongsiv_const_ovfl'
 ; CHECK-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
diff --git a/llvm/test/Analysis/DependenceAnalysis/symbolic-rdiv-overflow.ll b/llvm/test/Analysis/DependenceAnalysis/symbolic-rdiv-overflow.ll
index 9a019e988b418..c5ff9884a0c62 100644
--- a/llvm/test/Analysis/DependenceAnalysis/symbolic-rdiv-overflow.ll
+++ b/llvm/test/Analysis/DependenceAnalysis/symbolic-rdiv-overflow.ll
@@ -4,17 +4,17 @@
 ; RUN: opt < %s -disable-output "-passes=print<da>" -da-enable-dependence-test=symbolic-rdiv 2>&1 \
 ; RUN:     | FileCheck %s --check-prefixes=CHECK,CHECK-SYMBOLIC-RDIV
 
-; offset = -2;
-; for (i = 0; i < (1LL << 62); i++, offset += 2) {
-;   if (0 <= offset0)
-;     A[offset0] = 1;
+; for (i = 0; i < (1LL << 62); i++) {
+;   if (0 <= 2*i - 2)
+;     A[2*i - 2] = 1;
 ;   A[i] = 2;
 ; }
 ;
 ; FIXME: DependenceAnalysis currently detects no dependency between the two
-; stores, but it does exist.
-; The root cause is that the product of the BTC and the coefficient triggers an
-; overflow.
+; stores, but it does exist. For example, each store will access A[0] when i
+; is 1 and 0 respectively.
+; The root cause is that the product of the BTC and the coefficient 
+; ((1LL << 62) - 1 and 2) overflows in a signed sense.
 define void @symbolicrdiv_prod_ovfl(ptr %A) {
 ; CHECK-ALL-LABEL: 'symbolicrdiv_prod_ovfl'
 ; CHECK-ALL-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
@@ -61,8 +61,8 @@ exit:
   ret void
 }
 
-; offset0 = -4611686018427387904  // -2^62
-; offset1 =  4611686018427387904  // 2^62
+; offset0 = -4611686018427387904;  // -2^62
+; offset1 =  4611686018427387904;  // 2^62
 ; for (i = 0; i < (1LL << 62) - 100; i++) {
 ;   if (0 <= offset0)
 ;     A[offset0] = 1;
@@ -73,9 +73,15 @@ exit:
 ; }
 ;
 ; FIXME: DependenceAnalysis currently detects no dependency between the two
-; stores, but it does exist.
+; stores, but it does exist. For example,
+;
+;  memory access           | i == 2^61 | i == 2^61 + 2^59 | i == 2^61 + 2^60  
+; -------------------------|-----------|------------------|-------------------
+;  A[2*i - 2^62] (offset0) |           | A[2^60]          | A[2^61]           
+;  A[-i + 2^62]  (offset1) | A[2^61]   |                  | A[2^60]           
+;
 ; The root cause is that the calculation of the differenct between the two
-; constants (-2^62 and 2^62) triggers an overflow.
+; constants (-2^62 and 2^62) overflows in a signed sense.
 define void @symbolicrdiv_delta_ovfl(ptr %A) {
 ; CHECK-ALL-LABEL: 'symbolicrdiv_delta_ovfl'
 ; CHECK-ALL-NEXT:  Src: store i8 1, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.0, align 1
diff --git a/llvm/test/Analysis/DependenceAnalysis/weak-crossing-siv-overflow.ll b/llvm/test/Analysis/DependenceAnalysis/weak-crossing-siv-overflow.ll
index d04442f804700..3462dffb7cf92 100644
--- a/llvm/test/Analysis/DependenceAnalysis/weak-crossing-siv-overflow.ll
+++ b/llvm/test/Analysis/DependenceAnalysis/weak-crossing-siv-overflow.ll
@@ -11,13 +11,13 @@
 ;     A[3*i - 2] = 1;
 ; }
 ;
-; FIXME: DependencyAnalsysis currently detects no dependency between
+; FIXME: DependenceAnalsysis currently detects no dependency between
 ; `A[-3*i + INT64_MAX]` and `A[3*i - 2]`, but it does exist. For example,
 ;
-;  memory location  | -3*i + INT64_MAX | 3*i - 2
-; ------------------|------------------|-----------
-;  A[1]             | i = max_i        | i = 1
-;  A[INT64_MAX - 3] | i = 1            | i = max_i
+;  memory access       | i == 1           | i == max_i
+; ---------------------|------------------|------------------
+;  A[-3*i + INT64_MAX] | A[INT64_MAX - 3] | A[1]
+;  A[3*i - 2]          | A[1]             | A[INT64_MAX - 3]
 ;
 ; The root cause is that the calculation of the differenct between the two
 ; constants (INT64_MAX and -2) triggers an overflow.
@@ -73,13 +73,13 @@ exit:
 ;   A[3*i + 1] = 1;
 ; }
 ;
-; FIXME: DependencyAnalsysis currently detects no dependency between
+; FIXME: DependenceAnalsysis currently detects no dependency between
 ; `A[-3*i + INT64_MAX]` and `A[3*i - 2]`, but it does exist. For example,
 ;
-;  memory location  | -3*i + INT64_MAX | 3*i + 1
-; ------------------|------------------|--------------
-;  A[1]             | i = max_i        | i = 0
-;  A[INT64_MAX - 3] | i = 1            | i = max_i - 1
+;  memory access       | i == 0 | i == 1           | i == max_i - 1 | i == max_i
+; ---------------------|--------|------------------|----------------|------------------
+;  A[-3*i + INT64_MAX] |        | A[INT64_MAX - 3] | A[1]           |
+;  A[3*i + 1]          | A[1]   |                  |                | A[INT64_MAX - 3]
 ;
 ; The root cause is that the product of the BTC, the coefficient, and 2
 ; triggers an overflow.
diff --git a/llvm/test/Analysis/DependenceAnalysis/weak-zero-siv-overflow.ll b/llvm/test/Analysis/DependenceAnalysis/weak-zero-siv-overflow.ll
index 2ccd4a406e212..6317c387858d3 100644
--- a/llvm/test/Analysis/DependenceAnalysis/weak-zero-siv-overflow.ll
+++ b/llvm/test/Analysis/DependenceAnalysis/weak-zero-siv-overflow.ll
@@ -4,16 +4,15 @@
 ; RUN: opt < %s -disable-output "-passes=print<da>" -da-enable-dependence-test=weak-zero-siv 2>&1 \
 ; RUN:     | FileCheck %s --check-prefixes=CHECK,CHECK-WEAK-ZERO-SIV
 
-; offset = -2;
-; for (i = 0; i < (1LL << 62); i++, offset += 2) {
-;   if (0 <= offset)
-;     A[offset] = 1;
+; for (i = 0; i < (1LL << 62); i++) {
+;   if (0 <= 2*i - 2)
+;     A[2*i - 2] = 1;
 ;   A[2] = 2;
 ; }
 ;
 ; FIXME: DependenceAnalysis currently detects no dependency between the two
 ; stores, but it does exist. The root cause is that the product of the BTC and
-; the coefficient triggers an overflow.
+; the coefficient ((1LL << 62) - 1 and 2) overflows in a signed sense.
 ;
 define void @weakzero_dst_siv_prod_ovfl(ptr %A) {
 ; CHECK-ALL-LABEL: 'weakzero_dst_siv_prod_ovfl'
@@ -61,18 +60,17 @@ exit:
   ret void
 }
 
-; offset = -1;
-; for (i = 0; i < n; i++, offset += 2) {
-;   if (0 <= offset)
-;     A[offset] = 1;
+; for (i = 0; i < n; i++) {
+;   if (0 <= 2*i - 1)
+;     A[2*i - 1] = 1;
 ;   A[INT64_MAX] = 2;
 ; }
 ;
 ; FIXME: DependenceAnalysis currently detects no dependency between the two
 ; stores, but it does exist. When `%n` is 2^62, the value of `%offset` will be
 ; the same as INT64_MAX at the last iteration.
-; The root cause is that the calculation of the differenct between the two
-; constants (INT64_MAX and -1) triggers an overflow.
+; The root cause is that the calculation of the difference between the two
+; constants (INT64_MAX and -1) overflows in a signed sense.
 ;
 define void @weakzero_dst_siv_delta_ovfl(ptr %A, i64 %n) {
 ; CHECK-ALL-LABEL: 'weakzero_dst_siv_delta_ovfl'

>From 314ad42fb3b40e2a635ed5fd094e554033e8c4a3 Mon Sep 17 00:00:00 2001
From: Ryotaro Kasuga <kasuga.ryotaro at fujitsu.com>
Date: Wed, 29 Oct 2025 10:17:13 +0000
Subject: [PATCH 4/4] fix typo

---
 .../Analysis/DependenceAnalysis/weak-crossing-siv-overflow.ll | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/llvm/test/Analysis/DependenceAnalysis/weak-crossing-siv-overflow.ll b/llvm/test/Analysis/DependenceAnalysis/weak-crossing-siv-overflow.ll
index 3462dffb7cf92..ba57c7bf5736a 100644
--- a/llvm/test/Analysis/DependenceAnalysis/weak-crossing-siv-overflow.ll
+++ b/llvm/test/Analysis/DependenceAnalysis/weak-crossing-siv-overflow.ll
@@ -11,7 +11,7 @@
 ;     A[3*i - 2] = 1;
 ; }
 ;
-; FIXME: DependenceAnalsysis currently detects no dependency between
+; FIXME: DependenceAnalysis currently detects no dependency between
 ; `A[-3*i + INT64_MAX]` and `A[3*i - 2]`, but it does exist. For example,
 ;
 ;  memory access       | i == 1           | i == max_i
@@ -73,7 +73,7 @@ exit:
 ;   A[3*i + 1] = 1;
 ; }
 ;
-; FIXME: DependenceAnalsysis currently detects no dependency between
+; FIXME: DependenceAnalysis currently detects no dependency between
 ; `A[-3*i + INT64_MAX]` and `A[3*i - 2]`, but it does exist. For example,
 ;
 ;  memory access       | i == 0 | i == 1           | i == max_i - 1 | i == max_i



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