[SCHEDULE] Fix boundary check (#2126)

* Fix boundary check

* Add unittest

src/schedule/message_passing.cc

@@ -491,11 +491,12 @@ std::vector<Expr> MakeBoundCheck(
       IntSet s = EvalSet(value, iset_dmap);
       Expr vmin = s.min();
       Expr vmax = s.max();
-      if (vmin.type() != value.type() || !can_prove(vmin >= iv->dom->min)) {
+      // The range of `value` resides in [vmin, vmax]
+      if (vmin.type() != value.type() || !can_prove(vmin >= 0)) {
         preds.emplace_back(value >= 0);
       }
       if (vmax.type() != value.type() || !can_prove(vmax < iv->dom->extent)) {
-        preds.emplace_back(value < (iv->dom->extent - iv->dom->min));
+        preds.emplace_back(value < iv->dom->extent);
       }
     }
   }

tests/python/unittest/test_schedule_schedule_ops.py

@@ -12,6 +12,7 @@ def test_schedule0():
     assert isinstance(bounds, tvm.container.Map)
     stmt = tvm.schedule.ScheduleOps(s, bounds)
 
+
 def test_schedule1():
     m = tvm.var('m')
     l = tvm.var('l')
@@ -53,10 +54,13 @@ def test_schedule_scan():
     assert tuple(res.shape) == (m, n)
     s = tvm.create_schedule(res.op)
     s = s.normalize()
+    ir = tvm.lower(s, [s_state], simple_mode=True)
+    assert not hasattr(ir.body.body.body.body.rest.body.body.rest.body, "condition")
     bounds = tvm.schedule.InferBound(s)
     assert(bounds[res.op.scan_axis].min.value == 1)
     stmt = tvm.schedule.ScheduleOps(s, bounds)
 
+
 def test_inline_multi_reduce():
     def argmax_comp(x, y):
         idx = tvm.select((x[1] >= y[1]), x[0], y[0])
@@ -80,7 +84,6 @@ def test_inline_multi_reduce():
     stmt = tvm.schedule.ScheduleOps(s, bounds)
 
 
-
 def test_auto_inline():
     m = tvm.var('m')
     n = tvm.var('n')
@@ -96,6 +99,7 @@ def test_auto_inline():
     bounds = tvm.schedule.InferBound(s)
     stmt = tvm.schedule.ScheduleOps(s, bounds)
 
+
 def test_schedule_const_bound():
     n = 128
     A = tvm.placeholder((n,), name='A')
@@ -146,6 +150,7 @@ def test_scan_inline1():
     s[s_x1].compute_inline()
     stmt = tvm.lower(s, [x, res1, res2])
 
+
 def test_scan_inline2():
     m = tvm.var("m")
     n = tvm.var("n")
@@ -183,6 +188,7 @@ def test_schedule_cache():
     bounds = tvm.schedule.InferBound(s)
     stmt = tvm.schedule.ScheduleOps(s, bounds)
 
+
 def test_schedule_middle_cache():
     m = tvm.var('m')
     n = tvm.var('n')
@@ -202,7 +208,6 @@ def test_schedule_middle_cache():
     stmt = tvm.schedule.ScheduleOps(s, bounds)
 
 
-
 def test_schedule_cache_relayout1():
     m = tvm.var('m')
     n = tvm.var('n')
@@ -249,6 +254,7 @@ def test_schedule_cache_relayout3():
     bounds = tvm.schedule.InferBound(s)
     stmt = tvm.schedule.ScheduleOps(s, bounds)
 
+
 def test_schedule_cache_relayout4():
     def _compute(*indice):
         return A(*indice) + 1, B(*indice) / 2