From: Vlad Brezae <brezaevlad@gmail.com>
Date: Thu, 22 Jun 2017 20:15:53 +0000 (+0300)
Subject: [sgen] Performance improvement for ms_block_size computations
X-Git-Url: http://wien.tomnetworks.com/gitweb/?p=mono.git;a=commitdiff_plain;h=3ea09f9c8f10097e50b94702c1e4a06cb7517c4c

[sgen] Performance improvement for ms_block_size computations

This reduces regressions for switching from MS_BLOCK_SIZE compile time constant
to ms_block_size variable by 85% on the tests where this was showing up. In the
future we should implement a block allocator, which would, amongst other benefits,
enable us to remove the block-size/page-size dependency.
---

diff --git a/mono/sgen/sgen-marksweep.c b/mono/sgen/sgen-marksweep.c
index e496288a2e7..7711679e3cb 100644
--- a/mono/sgen/sgen-marksweep.c
+++ b/mono/sgen/sgen-marksweep.c
@@ -1409,10 +1409,10 @@ static inline void
 sweep_block_for_size (MSBlockInfo *block, int count, int obj_size)
 {
 	int obj_index;
+	void *obj = MS_BLOCK_OBJ_FOR_SIZE (block, 0, obj_size);
 
-	for (obj_index = 0; obj_index < count; ++obj_index) {
+	for (obj_index = 0; obj_index < count; ++obj_index, obj = (void*)((mword)obj + obj_size)) {
 		int word, bit;
-		void *obj = MS_BLOCK_OBJ_FOR_SIZE (block, obj_index, obj_size);
 
 		MS_CALC_MARK_BIT (word, bit, obj);
 		if (MS_MARK_BIT (block, word, bit)) {