From ed688aceee660abed27f84b18fa64e5d4af56fd9 Mon Sep 17 00:00:00 2001
From: florian <florian@freepascal.org>
Date: Wed, 4 Sep 2019 20:45:23 +0000
Subject: [PATCH] * remove packed from tdynarray, it is not needed and
especially 64 bit CPUs which require proper aligment, suffer from it
git-svn-id: trunk@42920 -
---
rtl/inc/dynarr.inc | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/rtl/inc/dynarr.inc b/rtl/inc/dynarr.inc
index 72a6d7c451..0fbb020f54 100644
--- a/rtl/inc/dynarr.inc
+++ b/rtl/inc/dynarr.inc
@@ -19,7 +19,14 @@ type
{ don't add new fields, the size is used }
{ to calculate memory requirements }
pdynarray = ^tdynarray;
- tdynarray = packed record
+ { removed packed here as
+ 1) both fields have typically the same size (2, 4 or 8 bytes), if this is not the case, packed
+ should be used only for this architecture
+ 2) the memory blocks are sufficiently well aligned
+ 3) in particular 64 bit CPUs which require natural alignment suffer from
+ the packed as it causes each field access being split in 8 single loads and appropriate shift operations
+ }
+ tdynarray = { packed } record
refcount : ptrint;
high : tdynarrayindex;
end;