core: fix constant fields values retrieval

jadx-core/src/main/java/jadx/core/codegen/InsnGen.java

@@ -402,7 +402,7 @@ public class InsnGen {
 
 			/* fallback mode instructions */
 			case IF:
-				assert isFallback();
+				assert isFallback() : "if insn in not fallback mode";
 				IfNode ifInsn = (IfNode) insn;
 				String cond = arg(insn.getArg(0)) + " " + ifInsn.getOp().getSymbol() + " "
 						+ (ifInsn.isZeroCmp() ? "0" : arg(insn.getArg(1)));

jadx-core/src/main/java/jadx/core/dex/nodes/ClassNode.java

@@ -13,6 +13,7 @@ import jadx.core.dex.info.FieldInfo;
 import jadx.core.dex.info.MethodInfo;
 import jadx.core.dex.instructions.args.ArgType;
 import jadx.core.dex.instructions.args.LiteralArg;
+import jadx.core.dex.instructions.args.PrimitiveType;
 import jadx.core.dex.nodes.parser.AnnotationsParser;
 import jadx.core.dex.nodes.parser.FieldValueAttr;
 import jadx.core.dex.nodes.parser.StaticValuesParser;
@@ -140,9 +141,9 @@ public class ClassNode extends LineAttrNode implements ILoadable {
 				if (accFlags.isStatic() && accFlags.isFinal()) {
 					FieldValueAttr fv = (FieldValueAttr) f.getAttributes().get(AttributeType.FIELD_VALUE);
 					if (fv != null && fv.getValue() != null) {
-						if (accFlags.isPublic())
+						if (accFlags.isPublic()) {
 							dex.getConstFields().put(fv.getValue(), f);
-						else
+						}
 						constFields.put(fv.getValue(), f);
 					}
 				}
@@ -237,34 +238,49 @@ public class ClassNode extends LineAttrNode implements ILoadable {
 		return fields;
 	}
 
-	public FieldNode getConstField(Object o) {
+	public FieldNode getConstField(Object obj) {
+		return getConstField(obj, true);
+	}
+
+	public FieldNode getConstField(Object obj, boolean searchGlobal) {
 		ClassNode cn = this;
 		FieldNode field;
 		do {
-            field = cn.constFields.get(o);
+			field = cn.constFields.get(obj);
 		}
 		while (field == null
 				&& (cn.clsInfo.getParentClass() != null)
 				&& (cn = dex.resolveClass(cn.clsInfo.getParentClass())) != null);
 
-		if (field == null)
-			field = dex.getConstFields().get(o);
+		if (field == null && searchGlobal) {
+			field = dex.getConstFields().get(obj);
+		}
 		return field;
 	}
 
 	public FieldNode getConstFieldByLiteralArg(LiteralArg arg) {
-		ArgType type = arg.getType();
+		PrimitiveType type = arg.getType().getPrimitiveType();
+		if (type == null) {
+			return null;
+		}
 		long literal = arg.getLiteral();
-
-		if (type.equals(ArgType.DOUBLE))
-			return getConstField(Double.longBitsToDouble(literal));
-		else if (type.equals(ArgType.FLOAT))
-			return getConstField(Float.intBitsToFloat((int) literal));
-		else if (Math.abs(literal) > 0x1) {
-			if (type.equals(ArgType.INT))
-				return getConstField((int) literal);
-			else if (type.equals(ArgType.LONG))
-				return getConstField(literal);
+		switch (type) {
+			case BOOLEAN:
+				return getConstField(literal == 1, false);
+			case CHAR:
+				return getConstField((char) literal, Math.abs(literal) > 1);
+			case BYTE:
+				return getConstField((byte) literal, Math.abs(literal) > 1);
+			case SHORT:
+				return getConstField((short) literal, Math.abs(literal) > 1);
+			case INT:
+				return getConstField((int) literal, Math.abs(literal) > 1);
+			case LONG:
+				return getConstField(literal, Math.abs(literal) > 1);
+			case FLOAT:
+				return getConstField(Float.intBitsToFloat((int) literal), true);
+			case DOUBLE:
+				return getConstField(Double.longBitsToDouble(literal), true);
 		}
 		return null;
 	}

jadx-core/src/main/java/jadx/core/dex/visitors/regions/ProcessVariables.java

@@ -13,9 +13,9 @@ import jadx.core.utils.RegionUtils;
 import jadx.core.utils.exceptions.JadxException;
 
 import java.util.ArrayList;
-import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Iterator;
+import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
@@ -65,7 +65,7 @@ public class ProcessVariables extends AbstractVisitor {
 
 	@Override
 	public void visit(MethodNode mth) throws JadxException {
-		final Map<RegisterArg, Usage> usageMap = new HashMap<RegisterArg, Usage>();
+		final Map<RegisterArg, Usage> usageMap = new LinkedHashMap<RegisterArg, Usage>();
 
 		// collect all variables usage
 		IRegionVisitor collect = new TracedRegionVisitor() {