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-rw-r--r--tests/examplefiles/test.bpl140
1 files changed, 140 insertions, 0 deletions
diff --git a/tests/examplefiles/test.bpl b/tests/examplefiles/test.bpl
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+++ b/tests/examplefiles/test.bpl
@@ -0,0 +1,140 @@
+/*
+ * Test Boogie rendering
+*/
+
+const N: int;
+axiom 0 <= N;
+
+procedure foo() {
+ break;
+}
+// array to sort as global array, because partition & quicksort have to
+var a: [int] int;
+var original: [int] int;
+var perm: [int] int;
+
+// Is array a of length N sorted?
+function is_sorted(a: [int] int, l: int, r: int): bool
+{
+ (forall j, k: int :: l <= j && j < k && k <= r ==> a[j] <= a[k])
+}
+
+// is range a[l:r] unchanged?
+function is_unchanged(a: [int] int, b: [int] int, l: int, r: int): bool {
+ (forall i: int :: l <= i && i <= r ==> a[i] == b[i])
+}
+
+function is_permutation(a: [int] int, original: [int] int, perm: [int] int, N: int): bool
+{
+ (forall k: int :: 0 <= k && k < N ==> 0 <= perm[k] && perm[k] < N) &&
+ (forall k, j: int :: 0 <= k && k < j && j < N ==> perm[k] != perm[j]) &&
+ (forall k: int :: 0 <= k && k < N ==> a[k] == original[perm[k]])
+}
+
+function count(a: [int] int, x: int, N: int) returns (int)
+{ if N == 0 then 0 else if a[N-1] == x then count(a, x, N - 1) + 1 else count(a, x, N-1) }
+
+
+/*
+function count(a: [int] int, x: int, N: int) returns (int)
+{ if N == 0 then 0 else if a[N-1] == x then count(a, x, N - 1) + 1 else count(a, x, N-1) }
+
+function is_permutation(a: [int] int, b: [int] int, l: int, r: int): bool {
+ (forall i: int :: l <= i && i <= r ==> count(a, a[i], r+1) == count(b, a[i], r+1))
+}
+*/
+
+procedure partition(l: int, r: int, N: int) returns (p: int)
+ modifies a, perm;
+ requires N > 0;
+ requires l >= 0 && l < r && r < N;
+ requires ((r+1) < N) ==> (forall k: int :: (k >= l && k <= r) ==> a[k] <= a[r+1]);
+ requires ((l-1) >= 0) ==> (forall k: int :: (k >= l && k <= r) ==> a[k] > a[l-1]);
+
+ /* a is a permutation of the original array original */
+ requires is_permutation(a, original, perm, N);
+
+ ensures (forall k: int :: (k >= l && k <= p ) ==> a[k] <= a[p]);
+ ensures (forall k: int :: (k > p && k <= r ) ==> a[k] > a[p]);
+ ensures p >= l && p <= r;
+ ensures is_unchanged(a, old(a), 0, l-1);
+ ensures is_unchanged(a, old(a), r+1, N);
+ ensures ((r+1) < N) ==> (forall k: int :: (k >= l && k <= r) ==> a[k] <= a[r+1]);
+ ensures ((l-1) >= 0) ==> (forall k: int :: (k >= l && k <= r) ==> a[k] > a[l-1]);
+
+ /* a is a permutation of the original array original */
+ ensures is_permutation(a, original, perm, N);
+{
+ var i: int;
+ var sv: int;
+ var pivot: int;
+ var tmp: int;
+
+ i := l;
+ sv := l;
+ pivot := a[r];
+
+ while (i < r)
+ invariant i <= r && i >= l;
+ invariant sv <= i && sv >= l;
+ invariant pivot == a[r];
+ invariant (forall k: int :: (k >= l && k < sv) ==> a[k] <= old(a[r]));
+ invariant (forall k: int :: (k >= sv && k < i) ==> a[k] > old(a[r]));
+
+ /* a is a permutation of the original array original */
+ invariant is_permutation(a, original, perm, N);
+
+ invariant is_unchanged(a, old(a), 0, l-1);
+ invariant is_unchanged(a, old(a), r+1, N);
+ invariant ((r+1) < N) ==> (forall k: int :: (k >= l && k <= r) ==> a[k] <= a[r+1]);
+ invariant ((l-1) >= 0) ==> (forall k: int :: (k >= l && k <= r) ==> a[k] > a[l-1]);
+ {
+ if ( a[i] <= pivot) {
+ tmp := a[i]; a[i] := a[sv]; a[sv] := tmp;
+ tmp := perm[i]; perm[i] := perm[sv]; perm[sv] := tmp;
+ sv := sv +1;
+ }
+ i := i + 1;
+ }
+
+ //swap
+ tmp := a[i]; a[i] := a[sv]; a[sv] := tmp;
+ tmp := perm[i]; perm[i] := perm[sv]; perm[sv] := tmp;
+
+ p := sv;
+}
+
+
+procedure quicksort(l: int, r: int, N: int)
+ modifies a, perm;
+
+ requires N > 0;
+ requires l >= 0 && l < r && r < N;
+ requires ((r+1) < N) ==> (forall k: int :: (k >= l && k <= r) ==> a[k] <= a[r+1]);
+ requires ((l-1) >= 0) ==> (forall k: int :: (k >= l && k <= r) ==> a[k] > a[l-1]);
+
+ /* a is a permutation of the original array original */
+ requires is_permutation(a, original, perm, N);
+
+ ensures ((r+1) < N) ==> (forall k: int :: (k >= l && k <= r) ==> a[k] <= a[r+1]);
+ ensures ((l-1) >= 0) ==> (forall k: int :: (k >= l && k <= r) ==> a[k] > a[l-1]);
+
+ ensures is_unchanged(a, old(a), 0, l-1);
+ ensures is_unchanged(a, old(a), r+1, N);
+ ensures is_sorted(a, l, r);
+
+ /* a is a permutation of the original array original */
+ ensures is_permutation(a, original, perm, N);
+{
+ var p: int;
+
+ call p := partition(l, r, N);
+
+ if ((p-1) > l) {
+ call quicksort(l, p-1, N);
+ }
+
+ if ((p+1) < r) {
+ call quicksort(p+1, r, N);
+ }
+}