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[PATCH 4/5] diff: use SWAP macro

From
René Scharfe <l.s.r@web.de>
Date
Jan 28, 2017, 21:41 UTC
Message-ID
<84944ecd-d14e-b5e9-7566-9ab2b68c02fb@web.de>
In-Reply-To
<8ef4c833-45bd-6831-0683-6d01f30aa518@web.de>

Use the macro SWAP to exchange the value of pairs of variables instead of swapping them manually with the help of a temporary variable. The resulting code is shorter and easier to read.

The two cases were not transformed by the semantic patch swap.cocci because it's extra careful and handles only cases where the types of all variables are the same -- and here we swap two ints and use an unsigned temporary variable for that. Nevertheless the conversion is safe, as the value range is preserved with and without the patch.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
---
 diff-no-index.c | 3 +--
 diff.c          | 4 +---
 2 files changed, 2 insertions(+), 5 deletions(-)
diff --git a/diff-no-index.c b/diff-no-index.c
index 1ae09894d7..df762fd0f7 100644
--- a/diff-no-index.c
+++ b/diff-no-index.c
@@ -185,8 +185,7 @@ static int queue_diff(struct diff_options *o,
 		struct diff_filespec *d1, *d2;
 
 		if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
-			unsigned tmp;
-			tmp = mode1; mode1 = mode2; mode2 = tmp;
+			SWAP(mode1, mode2);
 			SWAP(name1, name2);
 		}
 
diff --git a/diff.c b/diff.c
index 9de1ba264f..6c4f3f6b72 100644
--- a/diff.c
+++ b/diff.c
@@ -5117,11 +5117,9 @@ void diff_change(struct diff_options *options,
 		return;
 
 	if (DIFF_OPT_TST(options, REVERSE_DIFF)) {
-		unsigned tmp;
 		SWAP(old_mode, new_mode);
 		SWAP(old_sha1, new_sha1);
-		tmp = old_sha1_valid; old_sha1_valid = new_sha1_valid;
-			new_sha1_valid = tmp;
+		SWAP(old_sha1_valid, new_sha1_valid);
 		SWAP(old_dirty_submodule, new_dirty_submodule);
 	}
 
-- 
2.11.0
Previous: René ScharfeNext: Johannes Schindelin
Message 43 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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