IL2CPP: Refactor reconstructor for single data read with multiple passes

Il2CppInspector.Common/IL2CPP/ReconstructMetadata.cs

@@ -221,11 +221,10 @@ namespace Il2CppInspector
             if (metadata == null)
                 return;
 
-            (ulong ptr, int count) types = (0, 0);
+            // Read in all the required data once since we'll be using nested loops
+            var metaPtrData = new List<(ulong, int, ulong[], ulong[], int, int, int)>();
 
-            // Determine what each pointer is
             for (var i = 0; i < metaPtrsOrdered.Count; i++) {
-
                 // Pointers in this list
                 var ptrs = Image.ReadMappedArray<ulong>(metaPtrsOrdered[i], metaCountLimits[i]);
 
@@ -241,15 +240,37 @@ namespace Il2CppInspector
                 // First set of pointers that can be mapped into a data section in the image
                 var ptrsMappableData = ptrs.Take(foundMappableCount)
                         .TakeWhile(p => dataSections.Any(s => Image.MapVATR(p) >= s.ImageStart && Image.MapVATR(p) <= s.ImageEnd))
-                    .ToList();
+                        .ToArray();
 
-                var foundMappableDataCount = ptrsMappableData.Count;
+                var foundMappableDataCount = ptrsMappableData.Length;
+
+                metaPtrData.Add((metaPtrsOrdered[i], metaCountLimits[i], ptrs, ptrsMappableData, foundCount, foundMappableCount, foundMappableDataCount));
+            }
+
+            // Items we need to search for
+            var types =        (ptr: 0ul, count: -1);
+            var genericInsts = (ptr: 0ul, count: -1);
+
+            // Determine what each pointer is
+            // We need to do this in a certain order because validating some items relies on earlier items
+            while (metaPtrData.Any()) {
+
+                var foundTarget = 0ul;
+
+                // We loop repeatedly through every set of data looking for our next target item,
+                // remove the matching set from the list and then repeat the outer while loop
+                // until there is nothing left to find
+                foreach (var (ptr, count, ptrs, ptrsMappableData, foundCount, foundMappableCount, foundMappableDataCount) in metaPtrData) {
 
                     // Test for Il2CppType**
+                    // ---------------------
+                    if (types.ptr == 0) {
+
                         // We don't ever expect there to be less than 0x1000 types
                         if (foundMappableDataCount >= 0x1000) {
+
                             // This statement is quite slow. We could speed it up with a two-stage approach
-                    var testTypes = Image.ReadMappedObjectPointerArray<Il2CppType>(metaPtrsOrdered[i], foundMappableDataCount);
+                            var testTypes = Image.ReadMappedObjectPointerArray<Il2CppType>(ptr, foundMappableDataCount);
 
                             var foundTypes = 0;
                             foreach (var testType in testTypes) {
@@ -280,11 +301,27 @@ namespace Il2CppInspector
                                     break;
                             }
                             if (foundTypes >= 0x1000) {
-                        types = (metaPtrsOrdered[i], foundTypes);
+                                types = (ptr, foundTypes);
+                                foundTarget = ptr;
+                                break;
                             }
                         }
                     }
 
+                    // Test for Il2CppGenericInst**
+                    // ----------------------------
+
+                }
+
+                // Successfully found the item we were looking for; remove it from the list
+                if (foundTarget != 0ul)
+                    metaPtrData = metaPtrData.Where(m => foundTarget != m.Item1).ToList();
+
+                // We didn't find anything - break to avoid an infinite loop
+                else
+                    break;
+            }
+
             #region Debugging validation checks
 #if DEBUG
             // Used on non-obfuscated binaries during development to confirm the output is correct
@@ -299,6 +336,8 @@ namespace Il2CppInspector
             // Perform substitution
             MetadataRegistration.ptypes                    = types.ptr;
             MetadataRegistration.typesCount                = types.count;
+            MetadataRegistration.genericInsts              = genericInsts.ptr;
+            MetadataRegistration.genericInstsCount         = genericInsts.count;
 
             // Force MetadataRegistration to pass validation in Il2CppBinary.Configure()
             MetadataRegistration.typeDefinitionsSizesCount = 0;