r600/sfn: Don't scan the whole block for ready instructions

Limit the number of tested instructions and the number of
ready instructions that might be taken into account.

This reduces the time needed to run the scheduler significantly.

Fixes: 79ca456b4837b3bc21cf9ef3c03c505c4b4909f6
   r600/sfn: rewrite NIR backend

Signed-off-by: Gert Wollny <gert.wollny@collabora.com>
Reviewed-by: Filip Gawin <filip@gawin.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18212>

diff --git a/src/gallium/drivers/r600/sfn/sfn_scheduler.cpp b/src/gallium/drivers/r600/sfn/sfn_scheduler.cpp
index ea742f9..abeac56 100644 (file)
--- a/src/gallium/drivers/r600/sfn/sfn_scheduler.cpp
+++ b/src/gallium/drivers/r600/sfn/sfn_scheduler.cpp
@@ -913,7 +913,8 @@ bool BlockSheduler::collect_ready_type(std::list<T *>& ready, std::list<T *>& av
    auto i = available.begin();
    auto e = available.end();
 
-   while (i != e) {
+   int lookahead = 16;
+   while (i != e && ready.size() < 16 && lookahead-- > 0) {
       if ((*i)->ready()) {
          ready.push_back(*i);
          auto old_i = i;