From 5d583830991c014191fa50d6fb401215816716b5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lukas=20Tr=C3=BCmper?= <lukas.truemper@outlook.de>
Date: Thu, 17 Feb 2022 09:55:55 +0100
Subject: [PATCH 1/2] Bugfix: step width in iteration_length

---
 kerncraft/kernel.py            |  3 ++-
 kerncraft/symbolic/__init__.py |  1 +
 kerncraft/symbolic/utils.py    | 19 +++++++++++++++++++
 3 files changed, 22 insertions(+), 1 deletion(-)
 create mode 100644 kerncraft/symbolic/__init__.py
 create mode 100644 kerncraft/symbolic/utils.py

diff --git a/kerncraft/kernel.py b/kerncraft/kernel.py
index f8db9e7..3054bd4 100755
--- a/kerncraft/kernel.py
+++ b/kerncraft/kernel.py
@@ -37,6 +37,7 @@
 from . import incore_model
 from .pycparser_utils import clean_code, replace_id
 
+from kerncraft.symbolic.utils import int_ceil
 
 class LessParanthesizingCGenerator(CGenerator):
     def get_BinaryOp_precedence(self, n):
@@ -420,7 +421,7 @@ def iteration_length(self, dimension=None):
 
         for var_name, start, end, incr in loops:
             # This unspools the iterations:
-            length = end-start
+            length = int_ceil((end-start), incr)
             total_length = total_length*length
         return self.subs_consts(total_length)
 
diff --git a/kerncraft/symbolic/__init__.py b/kerncraft/symbolic/__init__.py
new file mode 100644
index 0000000..b63a01f
--- /dev/null
+++ b/kerncraft/symbolic/__init__.py
@@ -0,0 +1 @@
+from kerncraft.symbolic.utils import int_ceil, int_floor
diff --git a/kerncraft/symbolic/utils.py b/kerncraft/symbolic/utils.py
new file mode 100644
index 0000000..5099398
--- /dev/null
+++ b/kerncraft/symbolic/utils.py
@@ -0,0 +1,19 @@
+import sympy
+
+class int_floor(sympy.Function):
+    @classmethod
+    def eval(cls, x, y):
+        if x.is_Number and y.is_Number:
+            return x // y
+
+    def _eval_is_integer(self):
+        return True
+
+class int_ceil(sympy.Function):
+    @classmethod
+    def eval(cls, x, y):
+        if x.is_Number and y.is_Number:
+            return sympy.ceiling(x / y)
+
+    def _eval_is_integer(self):
+        return True

From 0aea54643f349135789cc3458c48dc0d61c592d0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lukas=20Tr=C3=BCmper?= <lukas.truemper@outlook.de>
Date: Thu, 17 Feb 2022 13:11:21 +0100
Subject: [PATCH 2/2] step width fixes

---
 kerncraft/kernel.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kerncraft/kernel.py b/kerncraft/kernel.py
index 3054bd4..e5c72ba 100755
--- a/kerncraft/kernel.py
+++ b/kerncraft/kernel.py
@@ -515,7 +515,7 @@ def global_iterator_to_indices(self, git=None):
             loop_var = symbol_pos_int(var_name)
 
             # This unspools the iterations:
-            length = end-start  # FIXME is incr handled correct here?
+            length = int_ceil((end-start), incr)
             counter = start+(((global_iterator*last_incr) // total_length)*incr) % length
             total_length = total_length*length
             last_incr = incr
@@ -543,7 +543,7 @@ def global_iterator(self):
         total_length = sympy.Integer(1)
         for var_name, start, end, incr in reversed(self._loop_stack):
             loop_var = symbol_pos_int(var_name)
-            length = end - start  # FIXME is incr handled correct here?
+            length = int_ceil((end-start), incr)
             global_iterator += (loop_var - start) * total_length
             total_length *= length
         return global_iterator