Thread a group of formula-groups together if possible

Just before about to thread a FG, look to left and right for
"mutually" independent FG's with some restrictions and thread
this group of FG's together treating it as a single but longer
computation load.

For now the restrictions are :-
All formula-groups in a FG "group" must have :-

1. Same length
2. Same relative position.
3. Same weight.

This is very helpful in cases similar to the below :
There are lots of (say 32) consecutive formula-groups
all with same "small" length (say 8) and same weight.
By conventional formula-group-threading the speed-up is
limited to 8x even if we have a 256 core processor, but
with this threading-multiple-formula-groups patch
(in this case) we can get a speed-up of 256x provided
we have a >= 256 core machine. So effectively with this
patch the speed-up is now only limited to the number of
cells in a range consisting of mutually indepdendent
formula-groups rather than number of cells in each
formula-group.

Change-Id: Ib25b5abbb583fa207e8befff9a908d14313f3d51
Reviewed-on: https://gerrit.libreoffice.org/79485
Tested-by: Jenkins
Reviewed-by: Luboš Luňák <l.lunak@collabora.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/sc/inc/interpretercontext.hxx b/sc/inc/interpretercontext.hxx
index 9fb2bc3993c5..c7598fef8cdc 100644
--- a/sc/inc/interpretercontext.hxx
+++ b/sc/inc/interpretercontext.hxx
@@ -28,7 +28,8 @@ struct ScLookupCacheMap;
 // SetNumberFormat() is not thread-safe, so calls to it need to be delayed to the main thread.
 struct DelayedSetNumberFormat
 {
-    SCROW mRow; // Used only with formula groups, so column and tab do not need to be stored.
+    SCROW mCol;
+    SCROW mRow;
     sal_uInt32 mnNumberFormat;
 };