From 2671c5d22d67071fed97e8d814466c38e7aa5148 Mon Sep 17 00:00:00 2001
From: caheckman <48068198+caheckman@users.noreply.github.com>
Date: Wed, 10 Jun 2020 17:17:06 -0400
Subject: [PATCH] Keep null records out of FID cache

---
 .../hash/FunctionBodyFunctionExtentGenerator.java | 15 ++++++++-------
 .../service/FIDFixedSizeMRUCachingFactory.java    |  3 +++
 .../feature/fid/service/FidHasherFactory.java     |  3 ---
 3 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/Ghidra/Features/FunctionID/src/main/java/ghidra/feature/fid/hash/FunctionBodyFunctionExtentGenerator.java b/Ghidra/Features/FunctionID/src/main/java/ghidra/feature/fid/hash/FunctionBodyFunctionExtentGenerator.java
index 92b84b7fc5..99a92ca5b2 100644
--- a/Ghidra/Features/FunctionID/src/main/java/ghidra/feature/fid/hash/FunctionBodyFunctionExtentGenerator.java
+++ b/Ghidra/Features/FunctionID/src/main/java/ghidra/feature/fid/hash/FunctionBodyFunctionExtentGenerator.java
@@ -19,12 +19,7 @@ import java.util.ArrayList;
 import java.util.List;
 
 import ghidra.program.model.address.AddressSetView;
-import ghidra.program.model.listing.CodeUnit;
-import ghidra.program.model.listing.Function;
-import ghidra.program.model.listing.Instruction;
-import ghidra.program.model.listing.InstructionIterator;
-import ghidra.program.model.listing.Listing;
-import ghidra.program.model.listing.Program;
+import ghidra.program.model.listing.*;
 
 /**
  * Calculates the function extent by the function body; i.e. what's saved
@@ -35,9 +30,15 @@ import ghidra.program.model.listing.Program;
 public class FunctionBodyFunctionExtentGenerator implements FunctionExtentGenerator {
 	@Override
 	public List<CodeUnit> calculateExtent(Function func) {
+		if (func == null) {
+			return List.of();
+		}
+		final AddressSetView body = func.getBody();
+		if (body.isEmpty()) {
+			return List.of();
+		}
 		ArrayList<CodeUnit> units = new ArrayList<CodeUnit>();
 
-		final AddressSetView body = func.getBody();
 		final Program program = func.getProgram();
 		final Listing listing = program.getListing();
 
diff --git a/Ghidra/Features/FunctionID/src/main/java/ghidra/feature/fid/service/FIDFixedSizeMRUCachingFactory.java b/Ghidra/Features/FunctionID/src/main/java/ghidra/feature/fid/service/FIDFixedSizeMRUCachingFactory.java
index 864d73a300..90f2fb36ee 100644
--- a/Ghidra/Features/FunctionID/src/main/java/ghidra/feature/fid/service/FIDFixedSizeMRUCachingFactory.java
+++ b/Ghidra/Features/FunctionID/src/main/java/ghidra/feature/fid/service/FIDFixedSizeMRUCachingFactory.java
@@ -49,6 +49,9 @@ public class FIDFixedSizeMRUCachingFactory implements Factory<Function, FidHashQ
 		}
 
 		value = delegate.get(func);
+		if (value == null) {
+			return null;
+		}
 		cache.put(entryPoint, value);
 		return value;
 	}
diff --git a/Ghidra/Features/FunctionID/src/main/java/ghidra/feature/fid/service/FidHasherFactory.java b/Ghidra/Features/FunctionID/src/main/java/ghidra/feature/fid/service/FidHasherFactory.java
index 617f3e3dac..6e46f10c84 100644
--- a/Ghidra/Features/FunctionID/src/main/java/ghidra/feature/fid/service/FidHasherFactory.java
+++ b/Ghidra/Features/FunctionID/src/main/java/ghidra/feature/fid/service/FidHasherFactory.java
@@ -35,9 +35,6 @@ class FidHasherFactory implements Factory<Function, FidHashQuad> {
 	@Override
 	public FidHashQuad get(Function function) {
 		try {
-			if (function == null) {
-				return null;
-			}
 			return hasher.hash(function);
 		}
 		catch (MemoryAccessException e) {