GP-1715 Guarantee default and evaluation models exist

Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/ProgramCompilerSpec.java

@@ -25,7 +25,9 @@ import ghidra.framework.options.Options;
 import ghidra.program.model.lang.*;
 import ghidra.program.model.listing.Program;
 import ghidra.util.*;
+import ghidra.util.exception.CancelledException;
 import ghidra.util.task.TaskMonitor;
+import ghidra.xml.XmlParseException;
 
 /**
  * A Program-specific version of the {@link CompilerSpec}.
@@ -150,7 +152,13 @@ public class ProgramCompilerSpec extends BasicCompilerSpec {
 		if (evalCalledModel != null) {
 			evalCalledName = evalCalledModel.getName();
 		}
-		modelXrefs(finalList, defaultName, evalName, evalCalledName);
+		try {
+			modelXrefs(finalList, defaultName, evalName, evalCalledName);
+		}
+		catch (XmlParseException e) {
+			Msg.warn(this, "Prototype model extensions NOT installed: " + e.getMessage());
+			usermodels.clear();
+		}
 		if (usermodels.isEmpty()) {
 			usermodels = null;
 		}
@@ -335,7 +343,7 @@ public class ProgramCompilerSpec extends BasicCompilerSpec {
 			case EVAL_CALLED:
 				return evalCalledModel;		// TODO: Currently no option
 		}
-		return null;
+		return defaultModel;
 	}
 
 	/**
@@ -370,6 +378,21 @@ public class ProgramCompilerSpec extends BasicCompilerSpec {
 			EVALUATION_MODEL_PROPERTY_NAME);
 	}
 
+	/**
+	 * Reset options to default (for this CompilerSpec)
+	 * This is for setLanguage to clear out strings that might belong to the old language.
+	 * @param monitor is the monitor for checking cancellation
+	 * @throws CancelledException if operation is cancelled externally
+	 */
+	protected void resetProgramOptions(TaskMonitor monitor) throws CancelledException {
+		Options decompilerPropertyList = program.getOptions(DECOMPILER_PROPERTY_LIST_NAME);
+		decompilerPropertyList.restoreDefaultValue(EVALUATION_MODEL_PROPERTY_NAME);
+		if (decompilerPropertyList.contains(DECOMPILER_OUTPUT_LANGUAGE)) {
+			decompilerPropertyList.restoreDefaultValue(DECOMPILER_OUTPUT_LANGUAGE);
+		}
+		SpecExtension.clearAllExtensions(program, monitor);
+	}
+
 	@Override
 	public boolean equals(Object obj) {
 		if (this == obj) {

Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/ProgramDB.java

@@ -2079,6 +2079,9 @@ public class ProgramDB extends DomainObjectAdapterDB implements Program, ChangeM
 				if (newCompilerSpecID != null) {
 					compilerSpec = ProgramCompilerSpec.getProgramCompilerSpec(this,
 						language.getCompilerSpecByID(newCompilerSpecID));
+					if (compilerSpec instanceof ProgramCompilerSpec) {
+						((ProgramCompilerSpec) compilerSpec).resetProgramOptions(monitor);
+					}
 				}
 				compilerSpecID = compilerSpec.getCompilerSpecID();
 				languageVersion = language.getVersion();

Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/SpecExtension.java

@@ -513,6 +513,24 @@ public class SpecExtension {
 		throw new XmlParseException("Unknown compiler spec extension: " + elName);
 	}
 
+	/**
+	 * Clear all spec extension options for the given program.
+	 * This is intended for internal use.  ProgramDB.installExtensions() must be called at
+	 * some later time to see the effect.
+	 * @param program is the given Program
+	 * @param monitor is a monitor for the operation
+	 * @throws CancelledException if something externally cancels the operation
+	 */
+	protected static void clearAllExtensions(Program program, TaskMonitor monitor)
+			throws CancelledException {
+		Options specOptions = program.getOptions(SpecExtension.SPEC_EXTENSION);
+		List<String> optionNames = specOptions.getOptionNames();
+		for (String name : optionNames) {
+			monitor.checkCanceled();
+			specOptions.removeOption(name);
+		}
+	}
+
 	/**
 	 * Check that the proposed callfixup extension does not collide with built-in fixups
 	 * @param doc is info about the proposed extension

Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/model/lang/BasicCompilerSpec.java

@@ -375,7 +375,7 @@ public class BasicCompilerSpec implements CompilerSpec {
 			case EVAL_CALLED:
 				return evalCalledModel;
 		}
-		return null;
+		return defaultModel;
 	}
 
 	@Override
@@ -453,17 +453,35 @@ public class BasicCompilerSpec implements CompilerSpec {
 	 * Build the model arrays given a complete list of models.
 	 * The array -models- contains all normal PrototypeModel objects
 	 * The array -allmodels- contains all models, including merge models.
+	 * We also check that a suitable model exists that matches a desired default name.
+	 * In principle, the XML schema should guarantee that the model exists, but if for some reason
+	 * it doesn't, an exception is thrown.
 	 * 
 	 * @param modelList is the complete list of models
+	 * @param putativeDefaultName is the desired name of the default model
+	 * @throws XmlParseException if a suitable default model cannot be found
 	 */
-	private void buildModelArrays(List<PrototypeModel> modelList) {
+	private void buildModelArrays(List<PrototypeModel> modelList, String putativeDefaultName)
+			throws XmlParseException {
+		if (putativeDefaultName == null) {
+			throw new XmlParseException("Compiler Spec " + description.getCompilerSpecName() +
+				" does not provide a default prototype");
+		}
 		int fullcount = 0;
 		int resolvecount = 0;
+		boolean foundDefault = false;
 		for (PrototypeModel model : modelList) {
 			fullcount += 1;
 			if (model.isMerged()) {
 				resolvecount += 1;
 			}
+			else if (putativeDefaultName.equals(model.getName())) {
+				foundDefault = true;	// Matching name AND not a merged model
+			}
+		}
+		if (!foundDefault) {
+			throw new XmlParseException("Could not find default model " + putativeDefaultName +
+				"for Compiler Spec " + description.getCompilerSpecName());
 		}
 		models = new PrototypeModel[fullcount - resolvecount];
 		allmodels = new PrototypeModel[fullcount];
@@ -485,16 +503,19 @@ public class BasicCompilerSpec implements CompilerSpec {
 
 	/**
 	 * Establish cross referencing to prototype models.
-	 * All xrefs are regenerated from a single complete list of PrototypeModels
+	 * All xrefs are regenerated from a single complete list of PrototypeModels.
+	 * The modelList must provide a model with name matching defaultName or
+	 * an exception is thrown.  (In theory the schema guarantees this model always exists)
 	 * 
 	 * @param modelList is the complete list of models
-	 * @param defaultName is the name to use for the default model (or null)
+	 * @param defaultName is the name to use for the default model
 	 * @param evalCurrent is the name to use for evaluating the current function (or null)
 	 * @param evalCalled is the name to use for evaluating called functions (or null)
+	 * @throws XmlParseException if there is no model matching defaultName
 	 */
 	protected void modelXrefs(List<PrototypeModel> modelList, String defaultName,
-			String evalCurrent, String evalCalled) {
-		buildModelArrays(modelList);
+			String evalCurrent, String evalCalled) throws XmlParseException {
+		buildModelArrays(modelList, defaultName);
 		callingConventionMap = new HashMap<>();
 		for (PrototypeModel model : models) {
 			String name = model.getName();
@@ -503,10 +524,7 @@ public class BasicCompilerSpec implements CompilerSpec {
 			}
 		}
 
-		defaultModel = null;
-		if (defaultName != null) {
-			defaultModel = callingConventionMap.get(defaultName);
-		}
+		defaultModel = callingConventionMap.get(defaultName);
 		evalCurrentModel = defaultModel; // The default evaluation is to assume default model
 		evalCalledModel = defaultModel;