From 1a996c48ac6435637e925ae3d83038a80feb0254 Mon Sep 17 00:00:00 2001
From: Paul Sokolovsky <pfalcon@users.sourceforge.net>
Date: Sat, 8 Feb 2014 22:49:46 +0200
Subject: [PATCH] Refactor list comparison code to mp_seq_cmp_objs().

---
 py/obj.h      |  1 +
 py/objlist.c  | 45 +--------------------------------------------
 py/sequence.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 51 insertions(+), 44 deletions(-)

diff --git a/py/obj.h b/py/obj.h
index 85462b3a8b..f372030b7e 100644
--- a/py/obj.h
+++ b/py/obj.h
@@ -400,3 +400,4 @@ void mp_seq_multiply(const void *items, uint item_sz, uint len, uint times, void
 bool m_seq_get_fast_slice_indexes(machine_uint_t len, mp_obj_t slice, machine_uint_t *begin, machine_uint_t *end);
 #define m_seq_copy(dest, src, len, item_sz) memcpy(dest, src, len * sizeof(item_sz))
 bool mp_seq_cmp_bytes(int op, const byte *data1, uint len1, const byte *data2, uint len2);
+bool mp_seq_cmp_objs(int op, const mp_obj_t *items1, uint len1, const mp_obj_t *items2, uint len2);
diff --git a/py/objlist.c b/py/objlist.c
index aa857e41c2..29d0c92c52 100644
--- a/py/objlist.c
+++ b/py/objlist.c
@@ -75,51 +75,8 @@ static bool list_cmp_helper(int op, mp_obj_t self_in, mp_obj_t another_in) {
     }
     mp_obj_list_t *self = self_in;
     mp_obj_list_t *another = another_in;
-    if (op == RT_BINARY_OP_EQUAL && self->len != another->len) {
-        return false;
-    }
 
-    // Let's deal only with > & >=
-    if (op == RT_BINARY_OP_LESS || op == RT_BINARY_OP_LESS_EQUAL) {
-        mp_obj_t t = self;
-        self = another;
-        another = t;
-        if (op == RT_BINARY_OP_LESS) {
-            op = RT_BINARY_OP_MORE;
-        } else {
-            op = RT_BINARY_OP_MORE_EQUAL;
-        }
-    }
-
-    int len = self->len < another->len ? self->len : another->len;
-    bool eq_status = true; // empty lists are equal
-    bool rel_status;
-    for (int i = 0; i < len; i++) {
-        eq_status = mp_obj_equal(self->items[i], another->items[i]);
-        if (op == RT_BINARY_OP_EQUAL && !eq_status) {
-            return false;
-        }
-        rel_status = (rt_binary_op(op, self->items[i], another->items[i]) == mp_const_true);
-        if (!eq_status && !rel_status) {
-            return false;
-        }
-    }
-
-    // If we had tie in the last element...
-    if (eq_status) {
-        // ... and we have lists of different lengths...
-        if (self->len != another->len) {
-            if (self->len < another->len) {
-                // ... then longer list length wins (we deal only with >)
-                return false;
-            }
-        } else if (op == RT_BINARY_OP_MORE) {
-            // Otherwise, if we have strict relation, equality means failure
-            return false;
-        }
-    }
-
-    return true;
+    return mp_seq_cmp_objs(op, self->items, self->len, another->items, another->len);
 }
 
 static mp_obj_t list_unary_op(int op, mp_obj_t self_in) {
diff --git a/py/sequence.c b/py/sequence.c
index 74b4fcfdf8..b344ed00b4 100644
--- a/py/sequence.c
+++ b/py/sequence.c
@@ -91,3 +91,52 @@ bool mp_seq_cmp_bytes(int op, const byte *data1, uint len1, const byte *data2, u
     }
     return true;
 }
+
+// Special-case comparison function for sequences of mp_obj_t
+// Don't pass RT_BINARY_OP_NOT_EQUAL here
+bool mp_seq_cmp_objs(int op, const mp_obj_t *items1, uint len1, const mp_obj_t *items2, uint len2) {
+    if (op == RT_BINARY_OP_EQUAL && len1 != len2) {
+        return false;
+    }
+
+    // Let's deal only with > & >=
+    if (op == RT_BINARY_OP_LESS || op == RT_BINARY_OP_LESS_EQUAL) {
+        SWAP(const mp_obj_t *, items1, items2);
+        SWAP(uint, len1, len2);
+        if (op == RT_BINARY_OP_LESS) {
+            op = RT_BINARY_OP_MORE;
+        } else {
+            op = RT_BINARY_OP_MORE_EQUAL;
+        }
+    }
+
+    int len = len1 < len2 ? len1 : len2;
+    bool eq_status = true; // empty lists are equal
+    bool rel_status;
+    for (int i = 0; i < len; i++) {
+        eq_status = mp_obj_equal(items1[i], items2[i]);
+        if (op == RT_BINARY_OP_EQUAL && !eq_status) {
+            return false;
+        }
+        rel_status = (rt_binary_op(op, items1[i], items2[i]) == mp_const_true);
+        if (!eq_status && !rel_status) {
+            return false;
+        }
+    }
+
+    // If we had tie in the last element...
+    if (eq_status) {
+        // ... and we have lists of different lengths...
+        if (len1 != len2) {
+            if (len1 < len2) {
+                // ... then longer list length wins (we deal only with >)
+                return false;
+            }
+        } else if (op == RT_BINARY_OP_MORE) {
+            // Otherwise, if we have strict relation, equality means failure
+            return false;
+        }
+    }
+
+    return true;
+}