diff --git a/llvm/test/Analysis/DependenceAnalysis/gcd-miv-overflow.ll b/llvm/test/Analysis/DependenceAnalysis/gcd-miv-overflow.ll index 9169ac323d834..618d14c75faad 100644 --- a/llvm/test/Analysis/DependenceAnalysis/gcd-miv-overflow.ll +++ b/llvm/test/Analysis/DependenceAnalysis/gcd-miv-overflow.ll @@ -56,6 +56,125 @@ loop: %ec = icmp eq i64 %i.inc, 100 br i1 %ec, label %exit, label %loop +exit: + ret void +} + +; max_i = INT64_MAX/6 // 1537228672809129301 +; for (long long i = 0; i <= max_i; i++) { +; A[-6*i + INT64_MAX] = 0; +; if (i) +; A[3*i - 2] = 1; +; } +; +; FIXME: DependenceAnalysis currently detects no dependency between the two +; stores, but it does exist. For example, +; +; memory access | i == 1 | i == (max_i + 1) / 2 | i == max_i +; ---------------------|--------|----------------------|------------------- +; A[-6*i + INT64_MAX] | | A[3*max_i - 2] | A[1] +; A[3*i - 2] | A[1] | | A[3*max_i - 2] +; +; +define void @gcdmiv_delta_ovfl(ptr %A) { +; CHECK-ALL-LABEL: 'gcdmiv_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-GCD-MIV-LABEL: 'gcdmiv_delta_ovfl' +; CHECK-GCD-MIV-NEXT: Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 0, ptr %idx.0, align 1 +; CHECK-GCD-MIV-NEXT: da analyze - consistent output [*]! +; CHECK-GCD-MIV-NEXT: Src: store i8 0, ptr %idx.0, align 1 --> Dst: store i8 1, ptr %idx.1, align 1 +; CHECK-GCD-MIV-NEXT: da analyze - none! +; CHECK-GCD-MIV-NEXT: Src: store i8 1, ptr %idx.1, align 1 --> Dst: store i8 1, ptr %idx.1, align 1 +; CHECK-GCD-MIV-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 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, -6 + %subscript.1.next = add nsw i64 %subscript.1, 3 + %exitcond = icmp sgt i64 %i.inc, 1537228672809129301 + br i1 %exitcond, label %exit, label %loop.header + +exit: + ret void +} + +; max_i = INT64_MAX/3 // 3074457345618258602 +; for (i = 0; i < max_i; i++) { +; A[3*i] = 0; +; A[-3*i - 3*m - INT64_MAX] = 1; +; } +; +; FIXME: DependenceAnalysis currently detects no dependency between the two +; stores, but it may exist. For example, consider `m = 1`. Then, +; `-3*m - INT64_MAX` is `INT64_MAX - 1`. So `-3*i - 3*m - INT64_MAX` is +; effectively `-3*i + (INT64_MAX - 1)`. Thus, accesses will be as follows: +; +; memory access | i == 1 | i == max_i - 1 +; ---------------------------|------------------|------------------ +; A[3*i] | A[3] | A[INT64_MAX - 4] +; A[-3*i - 3*m - INT64_MAX] | A[INT64_MAX - 4] | A[3] +; + +define void @gcdmiv_const_ovfl(ptr %A, i64 %m) { +; CHECK-ALL-LABEL: 'gcdmiv_const_ovfl' +; CHECK-ALL-NEXT: Src: store i8 0, ptr %gep.0, align 1 --> Dst: store i8 0, ptr %gep.0, align 1 +; CHECK-ALL-NEXT: da analyze - none! +; CHECK-ALL-NEXT: Src: store i8 0, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.1, align 1 +; CHECK-ALL-NEXT: da analyze - none! +; CHECK-ALL-NEXT: Src: store i8 1, ptr %gep.1, align 1 --> Dst: store i8 1, ptr %gep.1, align 1 +; CHECK-ALL-NEXT: da analyze - none! +; +; CHECK-GCD-MIV-LABEL: 'gcdmiv_const_ovfl' +; CHECK-GCD-MIV-NEXT: Src: store i8 0, ptr %gep.0, align 1 --> Dst: store i8 0, ptr %gep.0, align 1 +; CHECK-GCD-MIV-NEXT: da analyze - consistent output [*]! +; CHECK-GCD-MIV-NEXT: Src: store i8 0, ptr %gep.0, align 1 --> Dst: store i8 1, ptr %gep.1, align 1 +; CHECK-GCD-MIV-NEXT: da analyze - none! +; CHECK-GCD-MIV-NEXT: Src: store i8 1, ptr %gep.1, align 1 --> Dst: store i8 1, ptr %gep.1, align 1 +; CHECK-GCD-MIV-NEXT: da analyze - consistent output [*]! +; +entry: + %m.3 = mul nsw i64 -3, %m + %const = sub i64 %m.3, 9223372036854775807 + %guard = icmp ne i64 %const, 0 + br i1 %guard, label %loop, label %exit + +loop: + %i = phi i64 [ 0, %entry ], [ %i.inc, %loop ] + %offset.0 = phi i64 [ 0, %entry ], [ %offset.0.next, %loop ] + %offset.1 = phi i64 [ %const, %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 0, ptr %gep.0 + store i8 1, ptr %gep.1 + %i.inc = add nuw nsw i64 %i, 1 + %offset.0.next = add nsw i64 %offset.0, 3 + %offset.1.next = add nsw i64 %offset.1, -3 + %ec = icmp eq i64 %i.inc, 3074457345618258602 + br i1 %ec, label %exit, label %loop + exit: ret void }