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[PATCH 3/5] use SWAP macro

From
René Scharfe <l.s.r@web.de>
Date
Jan 28, 2017, 21:40 UTC
Message-ID
<187c2b39-40cf-7e07-b489-d40cdf5f9145@web.de>
In-Reply-To
<8ef4c833-45bd-6831-0683-6d01f30aa518@web.de>

Apply the semantic patch swap.cocci to convert hand-rolled swaps to use the macro SWAP. The resulting code is shorter and easier to read, the object code is effectively unchanged.

The patch for object.c had to be hand-edited in order to preserve the comment before the change; Coccinelle tried to eat it for some reason.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
---
 builtin/diff-tree.c | 4 +---
 builtin/diff.c      | 9 +++------
 diff-no-index.c     | 3 +--
 diff.c              | 8 +++-----
 graph.c             | 5 +----
 line-range.c        | 3 +--
 merge-recursive.c   | 5 +----
 object.c            | 4 +---
 pack-revindex.c     | 5 +----
 prio-queue.c        | 4 +---
 strbuf.h            | 4 +---
 11 files changed, 15 insertions(+), 39 deletions(-)
diff --git a/builtin/diff-tree.c b/builtin/diff-tree.c
index 806dd7a885..8ce00480cd 100644
--- a/builtin/diff-tree.c
+++ b/builtin/diff-tree.c
@@ -147,9 +147,7 @@ int cmd_diff_tree(int argc, const char **argv, const char *prefix)
 		tree1 = opt->pending.objects[0].item;
 		tree2 = opt->pending.objects[1].item;
 		if (tree2->flags & UNINTERESTING) {
-			struct object *tmp = tree2;
-			tree2 = tree1;
-			tree1 = tmp;
+			SWAP(tree2, tree1);
 		}
 		diff_tree_sha1(tree1->oid.hash,
 			       tree2->oid.hash,
diff --git a/builtin/diff.c b/builtin/diff.c
index 7f91f6d226..3d64b85337 100644
--- a/builtin/diff.c
+++ b/builtin/diff.c
@@ -45,12 +45,9 @@ static void stuff_change(struct diff_options *opt,
 		return;
 
 	if (DIFF_OPT_TST(opt, REVERSE_DIFF)) {
-		unsigned tmp;
-		const unsigned char *tmp_u;
-		const char *tmp_c;
-		tmp = old_mode; old_mode = new_mode; new_mode = tmp;
-		tmp_u = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_u;
-		tmp_c = old_name; old_name = new_name; new_name = tmp_c;
+		SWAP(old_mode, new_mode);
+		SWAP(old_sha1, new_sha1);
+		SWAP(old_name, new_name);
 	}
 
 	if (opt->prefix &&
diff --git a/diff-no-index.c b/diff-no-index.c
index f420786039..1ae09894d7 100644
--- a/diff-no-index.c
+++ b/diff-no-index.c
@@ -186,9 +186,8 @@ static int queue_diff(struct diff_options *o,
 
 		if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
 			unsigned tmp;
-			const char *tmp_c;
 			tmp = mode1; mode1 = mode2; mode2 = tmp;
-			tmp_c = name1; name1 = name2; name2 = tmp_c;
+			SWAP(name1, name2);
 		}
 
 		d1 = noindex_filespec(name1, mode1);
diff --git a/diff.c b/diff.c
index f08cd8e033..9de1ba264f 100644
--- a/diff.c
+++ b/diff.c
@@ -5118,13 +5118,11 @@ void diff_change(struct diff_options *options,
 
 	if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
 		unsigned tmp;
-		const unsigned char *tmp_c;
-		tmp = old_mode; old_mode = new_mode; new_mode = tmp;
-		tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
+		SWAP(old_mode, new_mode);
+		SWAP(old_sha1, new_sha1);
 		tmp = old_sha1_valid; old_sha1_valid = new_sha1_valid;
 			new_sha1_valid = tmp;
-		tmp = old_dirty_submodule; old_dirty_submodule = new_dirty_submodule;
-			new_dirty_submodule = tmp;
+		SWAP(old_dirty_submodule, new_dirty_submodule);
 	}
 
 	if (options->prefix &&
diff --git a/graph.c b/graph.c
index d4e8519c90..4c722303d2 100644
--- a/graph.c
+++ b/graph.c
@@ -997,7 +997,6 @@ static void graph_output_post_merge_line(struct git_graph *graph, struct strbuf
 static void graph_output_collapsing_line(struct git_graph *graph, struct strbuf *sb)
 {
 	int i;
-	int *tmp_mapping;
 	short used_horizontal = 0;
 	int horizontal_edge = -1;
 	int horizontal_edge_target = -1;
@@ -1132,9 +1131,7 @@ static void graph_output_collapsing_line(struct git_graph *graph, struct strbuf
 	/*
 	 * Swap mapping and new_mapping
 	 */
-	tmp_mapping = graph->mapping;
-	graph->mapping = graph->new_mapping;
-	graph->new_mapping = tmp_mapping;
+	SWAP(graph->mapping, graph->new_mapping);
 
 	/*
 	 * If graph->mapping indicates that all of the branch lines
diff --git a/line-range.c b/line-range.c
index de4e32f942..323399d16c 100644
--- a/line-range.c
+++ b/line-range.c
@@ -269,8 +269,7 @@ int parse_range_arg(const char *arg, nth_line_fn_t nth_line_cb,
 		return -1;
 
 	if (*begin && *end && *end < *begin) {
-		long tmp;
-		tmp = *end; *end = *begin; *begin = tmp;
+		SWAP(*end, *begin);
 	}
 
 	return 0;
diff --git a/merge-recursive.c b/merge-recursive.c
index d327209443..b7ff1ada3c 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -1390,14 +1390,11 @@ static int process_renames(struct merge_options *o,
 			branch1 = o->branch1;
 			branch2 = o->branch2;
 		} else {
-			struct rename *tmp;
 			renames1 = b_renames;
 			renames2Dst = &a_by_dst;
 			branch1 = o->branch2;
 			branch2 = o->branch1;
-			tmp = ren2;
-			ren2 = ren1;
-			ren1 = tmp;
+			SWAP(ren2, ren1);
 		}
 
 		if (ren1->processed)
diff --git a/object.c b/object.c
index 67d9a9e221..e680d881a4 100644
--- a/object.c
+++ b/object.c
@@ -104,9 +104,7 @@ struct object *lookup_object(const unsigned char *sha1)
 		 * that we do not need to walk the hash table the next
 		 * time we look for it.
 		 */
-		struct object *tmp = obj_hash[i];
-		obj_hash[i] = obj_hash[first];
-		obj_hash[first] = tmp;
+		SWAP(obj_hash[i], obj_hash[first]);
 	}
 	return obj;
 }
diff --git a/pack-revindex.c b/pack-revindex.c
index 6bc7c94033..1b7ebd8d7e 100644
--- a/pack-revindex.c
+++ b/pack-revindex.c
@@ -59,7 +59,6 @@ static void sort_revindex(struct revindex_entry *entries, unsigned n, off_t max)
 	 * be a no-op, as everybody lands in the same zero-th bucket.
 	 */
 	for (bits = 0; max >> bits; bits += DIGIT_SIZE) {
-		struct revindex_entry *swap;
 		unsigned i;
 
 		memset(pos, 0, BUCKETS * sizeof(*pos));
@@ -97,9 +96,7 @@ static void sort_revindex(struct revindex_entry *entries, unsigned n, off_t max)
 		 * Now "to" contains the most sorted list, so we swap "from" and
 		 * "to" for the next iteration.
 		 */
-		swap = from;
-		from = to;
-		to = swap;
+		SWAP(from, to);
 	}
 
 	/*
diff --git a/prio-queue.c b/prio-queue.c
index e4365b00d6..17252d231b 100644
--- a/prio-queue.c
+++ b/prio-queue.c
@@ -12,9 +12,7 @@ static inline int compare(struct prio_queue *queue, int i, int j)
 
 static inline void swap(struct prio_queue *queue, int i, int j)
 {
-	struct prio_queue_entry tmp = queue->array[i];
-	queue->array[i] = queue->array[j];
-	queue->array[j] = tmp;
+	SWAP(queue->array[i], queue->array[j]);
 }
 
 void prio_queue_reverse(struct prio_queue *queue)
diff --git a/strbuf.h b/strbuf.h
index 2262b12683..cf1b5409e7 100644
--- a/strbuf.h
+++ b/strbuf.h
@@ -109,9 +109,7 @@ extern void strbuf_attach(struct strbuf *, void *, size_t, size_t);
  */
 static inline void strbuf_swap(struct strbuf *a, struct strbuf *b)
 {
-	struct strbuf tmp = *a;
-	*a = *b;
-	*b = tmp;
+	SWAP(*a, *b);
 }
 
 

-- 
2.11.0
Previous: René ScharfeNext: Johannes Schindelin
Message 38 of 50 in “introduce SWAP macro”
  1. 0/5 introduce SWAP macroRené Scharfe, Jan 28, 2017
  2. 1/5 add SWAP macroRené Scharfe, Jan 28, 2017
  3. Johannes SchindelinJan 30, 2017
  4. René ScharfeJan 30, 2017
  5. Johannes SchindelinJan 30, 2017
  6. René ScharfeJan 30, 2017
  7. Johannes SchindelinJan 31, 2017
  8. René ScharfeJan 31, 2017
  9. Ramsay JonesFeb 1, 2017
  10. Johannes SchindelinFeb 1, 2017
  11. Johannes SchindelinJan 30, 2017
  12. René ScharfeJan 30, 2017
  13. Johannes SixtJan 30, 2017
  14. Johannes SchindelinJan 30, 2017
  15. René ScharfeJan 30, 2017
  16. Brandon WilliamsJan 30, 2017
  17. René ScharfeJan 31, 2017
  18. Jeff KingJan 31, 2017
  19. Junio C HamanoJan 31, 2017
  20. Jeff KingJan 31, 2017
  21. Johannes SchindelinFeb 1, 2017
  22. Jeff KingFeb 1, 2017
  23. René ScharfeFeb 1, 2017
  24. Junio C HamanoFeb 1, 2017
  25. René ScharfeFeb 7, 2017
  26. Junio C HamanoFeb 7, 2017
  27. Johannes SchindelinFeb 8, 2017
  28. Johannes SchindelinJan 31, 2017
  29. Jeff KingApr 24, 2017
  30. Jeff KingApr 24, 2017
  31. Duy NguyenApr 24, 2017
  32. René ScharfeApr 28, 2017
  33. Jeff KingApr 28, 2017
  34. René ScharfeApr 29, 2017
  35. Jeff KingApr 30, 2017
  36. René ScharfeMay 2, 2017
  37. 2/5 apply: use SWAP macroRené Scharfe, Jan 28, 2017
  38. 3/5 use SWAP macroRené Scharfe, Jan 28, 2017
  39. Johannes SchindelinJan 30, 2017
  40. René ScharfeJan 30, 2017
  41. Junio C HamanoJan 30, 2017
  42. René ScharfeJan 31, 2017
  43. 4/5 diff: use SWAP macroRené Scharfe, Jan 28, 2017
  44. Johannes SchindelinJan 30, 2017
  45. René ScharfeJan 30, 2017
  46. Junio C HamanoJan 30, 2017
  47. 5/5 graph: use SWAP macroRené Scharfe, Jan 28, 2017
  48. Johannes SchindelinJan 30, 2017
  49. René ScharfeJan 30, 2017
  50. Junio C HamanoJan 30, 2017

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