From 6a8a4592009b90c4572db798e52ad9532d4b225e Mon Sep 17 00:00:00 2001
From: rusefillc <rusefillc@gmail.com>
Date: Sat, 3 Dec 2022 00:53:02 -0500
Subject: [PATCH] reduce flash footprint by smarter code generation #4163

---
 .../rusefi/output/GetOutputValueConsumer.java | 38 +++++++++++++++++--
 .../java/com/rusefi/test/OutputsTest.java     | 15 +++++---
 2 files changed, 44 insertions(+), 9 deletions(-)

diff --git a/java_tools/configuration_definition/src/main/java/com/rusefi/output/GetOutputValueConsumer.java b/java_tools/configuration_definition/src/main/java/com/rusefi/output/GetOutputValueConsumer.java
index 474acad173..7d1611eafe 100644
--- a/java_tools/configuration_definition/src/main/java/com/rusefi/output/GetOutputValueConsumer.java
+++ b/java_tools/configuration_definition/src/main/java/com/rusefi/output/GetOutputValueConsumer.java
@@ -7,7 +7,10 @@ import com.rusefi.core.Pair;
 
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.function.Function;
 
 import static com.rusefi.output.ConfigStructure.ALIGNMENT_FILL_AT;
 import static com.rusefi.output.DataLogConsumer.UNUSED;
@@ -58,13 +61,42 @@ public class GetOutputValueConsumer implements ConfigurationConsumer {
 
     public String getContent() {
         StringBuilder getterBody = new StringBuilder();
+
+        StringBuilder switchBody = new StringBuilder();
+
+        HashMap<Integer, AtomicInteger> hashConflicts = new HashMap<>();
         for (Pair<String, String> pair : getterPairs) {
-            getterBody.append(getCompareName(pair.first));
-            getterBody.append("\t\treturn " + pair.second + ";\n");
+            hashConflicts.computeIfAbsent(HashUtil.hash(pair.first), integer -> new AtomicInteger(0)).incrementAndGet();
         }
 
+
+        for (Pair<String, String> pair : getterPairs) {
+            String returnLine = "\t\treturn " + pair.second + ";\n";
+
+            int hash = HashUtil.hash(pair.first);
+            if (hashConflicts.get(hash).get() == 1) {
+                switchBody.append("\t\tcase " + hash + ":\n");
+                switchBody.append("\t" + returnLine);
+
+            } else {
+
+                getterBody.append(getCompareName(pair.first));
+
+                getterBody.append(returnLine);
+            }
+        }
+
+        String fullSwitch = switchBody.length() == 0 ? "" :
+                ("\tint hash = djb2lowerCase(name);\n" +
+
+                        "\tswitch(hash) {\n" + switchBody + "\t}\n");
+
         return FILE_HEADER +
-                "float getOutputValueByName(const char *name) {\n" + getterBody + GetConfigValueConsumer.GET_METHOD_FOOTER;
+                "float getOutputValueByName(const char *name) {\n" +
+                fullSwitch +
+
+
+                getterBody + GetConfigValueConsumer.GET_METHOD_FOOTER;
     }
 
 }
diff --git a/java_tools/configuration_definition/src/test/java/com/rusefi/test/OutputsTest.java b/java_tools/configuration_definition/src/test/java/com/rusefi/test/OutputsTest.java
index 2129ece5a6..f07e83621f 100644
--- a/java_tools/configuration_definition/src/test/java/com/rusefi/test/OutputsTest.java
+++ b/java_tools/configuration_definition/src/test/java/com/rusefi/test/OutputsTest.java
@@ -147,12 +147,15 @@ public class OutputsTest {
                 "#include \"pch.h\"\n" +
                         "#include \"value_lookup.h\"\n" +
                         "float getOutputValueByName(const char *name) {\n" +
-                        "\tif (strEqualCaseInsensitive(name, \"issue_294_31\"))\n" +
-                        "\t\treturn engine->outputChannels.issue_294_31;\n" +
-                        "\tif (strEqualCaseInsensitive(name, \"enableFan1WithAc\"))\n" +
-                        "\t\treturn engine->outputChannels.enableFan1WithAc;\n" +
-                        "\tif (strEqualCaseInsensitive(name, \"hwChannel\"))\n" +
-                        "\t\treturn engine->outputChannels.hwChannel;\n" +
+                        "\tint hash = djb2lowerCase(name);\n" +
+                        "\tswitch(hash) {\n" +
+                        "\t\tcase -1571463185:\n" +
+                        "\t\t\treturn engine->outputChannels.issue_294_31;\n" +
+                        "\t\tcase -298185774:\n" +
+                        "\t\t\treturn engine->outputChannels.enableFan1WithAc;\n" +
+                        "\t\tcase -709106787:\n" +
+                        "\t\t\treturn engine->outputChannels.hwChannel;\n" +
+                        "\t}\n" +
                         "\treturn EFI_ERROR_CODE;\n" +
                         "}\n", outputValueConsumer.getContent());
     }