From 81c2c4a88103ecb4ad9f0ef41f569a1cf1d569e9 Mon Sep 17 00:00:00 2001
From: Jonathan G Rennison <j.g.rennison@gmail.com>
Date: Tue, 16 Jan 2024 23:15:56 +0000
Subject: [PATCH] Slightly speed up unordered iteration of FlowStatMap

---
 src/station_base.h            | 6 ++++++
 src/station_cmd.cpp           | 4 ++--
 src/table/newgrf_debug_data.h | 2 +-
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/station_base.h b/src/station_base.h
index 686d15bb16..4fd9df7444 100644
--- a/src/station_base.h
+++ b/src/station_base.h
@@ -22,6 +22,7 @@
 #include "bitmap_type.h"
 #include "core/alloc_type.hpp"
 #include "core/endian_type.hpp"
+#include "core/span_type.hpp"
 #include "strings_type.h"
 #include <map>
 #include <vector>
@@ -504,6 +505,11 @@ public:
 	}
 
 	void SortStorage();
+
+	span<const FlowStat> IterateUnordered() const
+	{
+		return span<const FlowStat>(this->flows_storage.data(), this->flows_storage.size());
+	}
 };
 
 struct GoodsEntryData : ZeroedMemoryAllocator {
diff --git a/src/station_cmd.cpp b/src/station_cmd.cpp
index 6141807952..99f74c593f 100644
--- a/src/station_cmd.cpp
+++ b/src/station_cmd.cpp
@@ -5629,7 +5629,7 @@ void FlowStatMap::RestrictFlows(StationID via)
 uint FlowStatMap::GetFlow() const
 {
 	uint ret = 0;
-	for (const FlowStat &it : *this) {
+	for (const FlowStat &it : this->IterateUnordered()) {
 		if (it.IsInvalid()) continue;
 		ret += (it.end() - 1)->first;
 	}
@@ -5644,7 +5644,7 @@ uint FlowStatMap::GetFlow() const
 uint FlowStatMap::GetFlowVia(StationID via) const
 {
 	uint ret = 0;
-	for (const FlowStat &it : *this) {
+	for (const FlowStat &it : this->IterateUnordered()) {
 		if (it.IsInvalid()) continue;
 		ret += it.GetShare(via);
 	}
diff --git a/src/table/newgrf_debug_data.h b/src/table/newgrf_debug_data.h
index 845ee0e811..008d52fbf7 100644
--- a/src/table/newgrf_debug_data.h
+++ b/src/table/newgrf_debug_data.h
@@ -2109,7 +2109,7 @@ class NIHStationStruct : public NIHelper {
 				}
 				if (ge->data != nullptr && ge->data->flows.size() > 0) {
 					size_t total_shares = 0;
-					for (const FlowStat &fs : ge->data->flows) {
+					for (const FlowStat &fs : ge->data->flows.IterateUnordered()) {
 						total_shares += fs.size();
 					}
 					seprintf(buffer, lastof(buffer), "    Flows: %u, total shares: %u", (uint)ge->data->flows.size(), (uint)total_shares);