AK: Add global FlatPtr typedef. It's u32 or u64, based on sizeof(void*)

Use this instead of uintptr_t throughout the codebase. This makes it
possible to pass a FlatPtr to something that has u32 and u64 overloads.

36 files changed, 165 insertions, 162 deletions

diff --git a/AK/HashFunctions.h b/AK/HashFunctions.h
index 458bad796c..ffa21a0190 100644
--- a/AK/HashFunctions.h
+++ b/AK/HashFunctions.h
@@ -51,7 +51,7 @@ inline unsigned u64_hash(u64 key)
     return pair_int_hash(first, last);
 }
 
-inline unsigned ptr_hash(uintptr_t ptr)
+inline unsigned ptr_hash(FlatPtr ptr)
 {
     if constexpr(sizeof(ptr) == 8)
         return u64_hash((u64)ptr);
@@ -61,5 +61,5 @@ inline unsigned ptr_hash(uintptr_t ptr)
 
 inline unsigned ptr_hash(const void* ptr)
 {
-    return ptr_hash((uintptr_t)(ptr));
+    return ptr_hash((FlatPtr)(ptr));
 }
diff --git a/AK/Types.h b/AK/Types.h
index ce9e0f651f..aab08774e5 100644
--- a/AK/Types.h
+++ b/AK/Types.h
@@ -28,6 +28,7 @@
 
 #include <AK/IterationDecision.h>
 #include <AK/Platform.h>
+#include <AK/StdLibExtras.h>
 
 #ifdef __serenity__
 typedef unsigned char u8;
@@ -89,6 +90,8 @@ typedef __PTRDIFF_TYPE__ __ptrdiff_t;
 
 #endif
 
+typedef Conditional<sizeof(void*) == 8, u64, u32>::Type FlatPtr;
+
 constexpr unsigned KB = 1024;
 constexpr unsigned MB = KB * KB;
 constexpr unsigned GB = KB * KB * KB;
diff --git a/DevTools/Inspector/RemoteObject.h b/DevTools/Inspector/RemoteObject.h
index b8d5d680ca..89c0e93f21 100644
--- a/DevTools/Inspector/RemoteObject.h
+++ b/DevTools/Inspector/RemoteObject.h
@@ -42,8 +42,8 @@ public:
     RemoteObject* parent { nullptr };
     NonnullOwnPtrVector<RemoteObject> children;
 
-    uintptr_t address { 0 };
-    uintptr_t parent_address { 0 };
+    FlatPtr address { 0 };
+    FlatPtr parent_address { 0 };
     String class_name;
     String name;
 
diff --git a/DevTools/Inspector/RemoteObjectPropertyModel.cpp b/DevTools/Inspector/RemoteObjectPropertyModel.cpp
index c4e69a16f3..adb650235d 100644
--- a/DevTools/Inspector/RemoteObjectPropertyModel.cpp
+++ b/DevTools/Inspector/RemoteObjectPropertyModel.cpp
@@ -75,7 +75,7 @@ void RemoteObjectPropertyModel::update()
 void RemoteObjectPropertyModel::set_data(const GUI::ModelIndex& index, const GUI::Variant& new_value)
 {
     auto& property = m_properties[index.row()];
-    uintptr_t address = m_object.address;
+    FlatPtr address = m_object.address;
     RemoteProcess::the().set_property(address, property.name.to_string(), new_value.to_string());
     property.value = new_value.to_string();
     did_update();
diff --git a/DevTools/Inspector/RemoteProcess.cpp b/DevTools/Inspector/RemoteProcess.cpp
index 9f3adab9a7..4c642ee45e 100644
--- a/DevTools/Inspector/RemoteProcess.cpp
+++ b/DevTools/Inspector/RemoteProcess.cpp
@@ -65,14 +65,14 @@ void RemoteProcess::handle_get_all_objects_response(const JsonObject& response)
     auto& object_array = objects.as_array();
 
     NonnullOwnPtrVector<RemoteObject> remote_objects;
-    HashMap<uintptr_t, RemoteObject*> objects_by_address;
+    HashMap<FlatPtr, RemoteObject*> objects_by_address;
 
     for (auto& value : object_array.values()) {
         ASSERT(value.is_object());
         auto& object = value.as_object();
         auto remote_object = make<RemoteObject>();
-        remote_object->address = object.get("address").to_number<uintptr_t>();
-        remote_object->parent_address = object.get("parent").to_number<uintptr_t>();
+        remote_object->address = object.get("address").to_number<FlatPtr>();
+        remote_object->parent_address = object.get("parent").to_number<FlatPtr>();
         remote_object->name = object.get("name").to_string();
         remote_object->class_name = object.get("class_name").to_string();
         remote_object->json = object;
@@ -105,7 +105,7 @@ void RemoteProcess::send_request(const JsonObject& request)
     m_socket->write(serialized);
 }
 
-void RemoteProcess::set_inspected_object(uintptr_t address)
+void RemoteProcess::set_inspected_object(FlatPtr address)
 {
     JsonObject request;
     request.set("type", "SetInspectedObject");
@@ -113,7 +113,7 @@ void RemoteProcess::set_inspected_object(uintptr_t address)
     send_request(request);
 }
 
-void RemoteProcess::set_property(uintptr_t object, const StringView& name, const JsonValue& value)
+void RemoteProcess::set_property(FlatPtr object, const StringView& name, const JsonValue& value)
 {
     JsonObject request;
     request.set("type", "SetProperty");
diff --git a/DevTools/Inspector/RemoteProcess.h b/DevTools/Inspector/RemoteProcess.h
index 6e22e2444a..d81ad4d9a3 100644
--- a/DevTools/Inspector/RemoteProcess.h
+++ b/DevTools/Inspector/RemoteProcess.h
@@ -45,9 +45,9 @@ public:
     RemoteObjectGraphModel& object_graph_model() { return *m_object_graph_model; }
     const NonnullOwnPtrVector<RemoteObject>& roots() const { return m_roots; }
 
-    void set_inspected_object(uintptr_t);
+    void set_inspected_object(FlatPtr);
 
-    void set_property(uintptr_t object, const StringView& name, const JsonValue& value);
+    void set_property(FlatPtr object, const StringView& name, const JsonValue& value);
 
     Function<void()> on_update;
 
diff --git a/DevTools/ProfileViewer/Profile.cpp b/DevTools/ProfileViewer/Profile.cpp
index e4984b7bab..3e913a8eae 100644
--- a/DevTools/ProfileViewer/Profile.cpp
+++ b/DevTools/ProfileViewer/Profile.cpp
@@ -84,7 +84,7 @@ void Profile::rebuild_tree()
         return new_root;
     };
 
-    HashTable<uintptr_t> live_allocations;
+    HashTable<FlatPtr> live_allocations;
 
     for (auto& event : m_events) {
         if (has_timestamp_filter_range()) {
@@ -207,10 +207,10 @@ OwnPtr<Profile> Profile::load_from_perfcore_file(const StringView& path)
         event.type = perf_event.get("type").to_string();
 
         if (event.type == "malloc") {
-            event.ptr = perf_event.get("ptr").to_number<uintptr_t>();
+            event.ptr = perf_event.get("ptr").to_number<FlatPtr>();
             event.size = perf_event.get("size").to_number<size_t>();
         } else if (event.type == "free") {
-            event.ptr = perf_event.get("ptr").to_number<uintptr_t>();
+            event.ptr = perf_event.get("ptr").to_number<FlatPtr>();
         }
 
         auto stack_array = perf_event.get("stack").as_array();
@@ -239,7 +239,7 @@ OwnPtr<Profile> Profile::load_from_perfcore_file(const StringView& path)
         if (event.frames.size() < 2)
             continue;
 
-        uintptr_t innermost_frame_address = event.frames.at(1).address;
+        FlatPtr innermost_frame_address = event.frames.at(1).address;
         event.in_kernel = innermost_frame_address >= 0xc0000000;
 
         events.append(move(event));
diff --git a/DevTools/ProfileViewer/Profile.h b/DevTools/ProfileViewer/Profile.h
index 3c509f463c..04c96d9c56 100644
--- a/DevTools/ProfileViewer/Profile.h
+++ b/DevTools/ProfileViewer/Profile.h
@@ -120,7 +120,7 @@ public:
     struct Event {
         u64 timestamp { 0 };
         String type;
-        uintptr_t ptr { 0 };
+        FlatPtr ptr { 0 };
         size_t size { 0 };
         bool in_kernel { false };
         Vector<Frame> frames;
diff --git a/Kernel/ACPI/ACPIStaticParser.cpp b/Kernel/ACPI/ACPIStaticParser.cpp
index eb97518574..a55c16c7e0 100644
--- a/Kernel/ACPI/ACPIStaticParser.cpp
+++ b/Kernel/ACPI/ACPIStaticParser.cpp
@@ -247,7 +247,7 @@ namespace ACPI {
             dbg() << "ACPI: Looking for RSDP in EBDA @ V " << (void*)rsdp_str << ", P " << (void*)p_rsdp_str;
 #endif
             if (!strncmp("RSD PTR ", rsdp_str, strlen("RSD PTR ")))
-                return PhysicalAddress((uintptr_t)p_rsdp_str);
+                return PhysicalAddress((FlatPtr)p_rsdp_str);
             p_rsdp_str += 16;
         }
         return {};
@@ -262,7 +262,7 @@ namespace ACPI {
             dbg() << "ACPI: Looking for RSDP in BIOS ROM area @ V " << (void*)rsdp_str << ", P " << (void*)p_rsdp_str;
 #endif
             if (!strncmp("RSD PTR ", rsdp_str, strlen("RSD PTR ")))
-                return PhysicalAddress((uintptr_t)p_rsdp_str);
+                return PhysicalAddress((FlatPtr)p_rsdp_str);
             p_rsdp_str += 16;
         }
         return {};
@@ -320,8 +320,8 @@ namespace ACPI {
         auto main_sdt_region = MM.allocate_kernel_region(xsdt.page_base(), PAGE_SIZE, "ACPI Static Parsing search_table_in_xsdt()", Region::Access::Read, false, true);
         auto* xsdt_ptr = (volatile Structures::XSDT*)main_sdt_region->vaddr().offset(xsdt.offset_in_page().get()).as_ptr();
         for (u32 i = 0; i < ((xsdt_ptr->h.length - sizeof(Structures::SDTHeader)) / sizeof(u64)); i++) {
-            if (match_table_signature(PhysicalAddress((uintptr_t)xsdt_ptr->table_ptrs[i]), signature))
-                return PhysicalAddress((uintptr_t)xsdt_ptr->table_ptrs[i]);
+            if (match_table_signature(PhysicalAddress((FlatPtr)xsdt_ptr->table_ptrs[i]), signature))
+                return PhysicalAddress((FlatPtr)xsdt_ptr->table_ptrs[i]);
         }
         return {};
     }
@@ -347,8 +347,8 @@ namespace ACPI {
         auto* rsdt_ptr = (volatile Structures::RSDT*)main_sdt_region->vaddr().offset(rsdt.offset_in_page().get()).as_ptr();
 
         for (u32 i = 0; i < ((rsdt_ptr->h.length - sizeof(Structures::SDTHeader)) / sizeof(u32)); i++) {
-            if (match_table_signature(PhysicalAddress((uintptr_t)rsdt_ptr->table_ptrs[i]), signature))
-                return PhysicalAddress((uintptr_t)rsdt_ptr->table_ptrs[i]);
+            if (match_table_signature(PhysicalAddress((FlatPtr)rsdt_ptr->table_ptrs[i]), signature))
+                return PhysicalAddress((FlatPtr)rsdt_ptr->table_ptrs[i]);
         }
         return {};
     }
diff --git a/Kernel/ACPI/DMIDecoder.cpp b/Kernel/ACPI/DMIDecoder.cpp
index 0c2ee75b6c..9b6e3e2358 100644
--- a/Kernel/ACPI/DMIDecoder.cpp
+++ b/Kernel/ACPI/DMIDecoder.cpp
@@ -134,7 +134,7 @@ void DMIDecoder::enumerate_smbios_tables()
 
         size_t table_size = get_table_size(p_table);
         p_table = p_table.offset(table_size);
-        v_table_ptr = (SMBIOS::TableHeader*)((uintptr_t)v_table_ptr + table_size);
+        v_table_ptr = (SMBIOS::TableHeader*)((FlatPtr)v_table_ptr + table_size);
 #ifdef SMBIOS_DEBUG
         dbg() << "DMIDecoder: Next table @ P 0x" << p_table.get();
 #endif
@@ -221,7 +221,7 @@ PhysicalAddress DMIDecoder::find_entry64bit_point()
         dbg() << "DMI Decoder: Looking for 64 bit Entry point @ V " << (void*)entry_str << " P " << (void*)tested_physical_ptr;
 #endif
         if (!strncmp("_SM3_", entry_str, strlen("_SM3_")))
-            return PhysicalAddress((uintptr_t)tested_physical_ptr);
+            return PhysicalAddress((FlatPtr)tested_physical_ptr);
 
         tested_physical_ptr += 16;
     }
@@ -239,7 +239,7 @@ PhysicalAddress DMIDecoder::find_entry32bit_point()
         dbg() << "DMI Decoder: Looking for 32 bit Entry point @ V " << (void*)entry_str << " P " << (void*)tested_physical_ptr;
 #endif
         if (!strncmp("_SM_", entry_str, strlen("_SM_")))
-            return PhysicalAddress((uintptr_t)tested_physical_ptr);
+            return PhysicalAddress((FlatPtr)tested_physical_ptr);
 
         tested_physical_ptr += 16;
     }
@@ -264,7 +264,7 @@ u64 DMIDecoder::get_bios_characteristics()
     auto* bios_info = (SMBIOS::BIOSInfo*)get_smbios_physical_table_by_type(0).as_ptr();
     ASSERT(bios_info != nullptr);
 
-    klog() << "DMIDecoder: BIOS info @ " << PhysicalAddress((uintptr_t)bios_info);
+    klog() << "DMIDecoder: BIOS info @ " << PhysicalAddress((FlatPtr)bios_info);
     return bios_info->bios_characteristics;
 }
 
diff --git a/Kernel/ACPI/MultiProcessorParser.cpp b/Kernel/ACPI/MultiProcessorParser.cpp
index 6e46ecbe04..0b405b95b1 100644
--- a/Kernel/ACPI/MultiProcessorParser.cpp
+++ b/Kernel/ACPI/MultiProcessorParser.cpp
@@ -45,9 +45,9 @@ void MultiProcessorParser::initialize()
 
 MultiProcessorParser::MultiProcessorParser()
     : m_floating_pointer(search_floating_pointer())
-    , m_operable((m_floating_pointer != (uintptr_t) nullptr))
+    , m_operable((m_floating_pointer != (FlatPtr) nullptr))
 {
-    if (m_floating_pointer != (uintptr_t) nullptr) {
+    if (m_floating_pointer != (FlatPtr) nullptr) {
         klog() << "MultiProcessor: Floating Pointer Structure @ " << PhysicalAddress(m_floating_pointer);
         parse_floating_pointer_data();
         parse_configuration_table();
@@ -89,7 +89,7 @@ void MultiProcessorParser::parse_configuration_table()
             p_entry = (MultiProcessor::EntryHeader*)(u32)p_entry + (u8)MultiProcessor::ConfigurationTableEntryLength::Processor;
             break;
         case ((u8)MultiProcessor::ConfigurationTableEntryType::Bus):
-            m_bus_entries.append((uintptr_t)p_entry);
+            m_bus_entries.append((FlatPtr)p_entry);
             entry = (MultiProcessor::EntryHeader*)(u32)entry + (u8)MultiProcessor::ConfigurationTableEntryLength::Bus;
             p_entry = (MultiProcessor::EntryHeader*)(u32)p_entry + (u8)MultiProcessor::ConfigurationTableEntryLength::Bus;
             break;
@@ -98,7 +98,7 @@ void MultiProcessorParser::parse_configuration_table()
             p_entry = (MultiProcessor::EntryHeader*)(u32)p_entry + (u8)MultiProcessor::ConfigurationTableEntryLength::IOAPIC;
             break;
         case ((u8)MultiProcessor::ConfigurationTableEntryType::IO_Interrupt_Assignment):
-            m_io_interrupt_redirection_entries.append((uintptr_t)p_entry);
+            m_io_interrupt_redirection_entries.append((FlatPtr)p_entry);
             entry = (MultiProcessor::EntryHeader*)(u32)entry + (u8)MultiProcessor::ConfigurationTableEntryLength::IO_Interrupt_Assignment;
             p_entry = (MultiProcessor::EntryHeader*)(u32)p_entry + (u8)MultiProcessor::ConfigurationTableEntryLength::IO_Interrupt_Assignment;
             break;
@@ -124,20 +124,20 @@ void MultiProcessorParser::parse_configuration_table()
     }
 }
 
-uintptr_t MultiProcessorParser::search_floating_pointer()
+FlatPtr MultiProcessorParser::search_floating_pointer()
 {
-    uintptr_t mp_floating_pointer = (uintptr_t) nullptr;
+    FlatPtr mp_floating_pointer = (FlatPtr) nullptr;
     auto region = MM.allocate_kernel_region(PhysicalAddress(0), PAGE_SIZE, "MultiProcessor Parser Floating Pointer Structure Finding", Region::Access::Read);
     u16 ebda_seg = (u16) * ((uint16_t*)((region->vaddr().get() & PAGE_MASK) + 0x40e));
     klog() << "MultiProcessor: Probing EBDA, Segment 0x" << String::format("%x", ebda_seg);
 
     mp_floating_pointer = search_floating_pointer_in_ebda(ebda_seg);
-    if (mp_floating_pointer != (uintptr_t) nullptr)
+    if (mp_floating_pointer != (FlatPtr) nullptr)
         return mp_floating_pointer;
     return search_floating_pointer_in_bios_area();
 }
 
-uintptr_t MultiProcessorParser::search_floating_pointer_in_ebda(u16 ebda_segment)
+FlatPtr MultiProcessorParser::search_floating_pointer_in_ebda(u16 ebda_segment)
 {
     auto floating_pointer_region = MM.allocate_kernel_region(PhysicalAddress(page_base_of((u32)(ebda_segment << 4))), PAGE_ROUND_UP(1024), "MultiProcessor Parser floating_pointer Finding #1", Region::Access::Read, false, true);
     char* p_floating_pointer_str = (char*)(PhysicalAddress(ebda_segment << 4).as_ptr());
@@ -146,12 +146,12 @@ uintptr_t MultiProcessorParser::search_floating_pointer_in_ebda(u16 ebda_segment
         dbg() << "MultiProcessor: Looking for floating pointer structure in EBDA @ V0x " << String::format("%x", floating_pointer_str) << ", P0x" << String::format("%x", p_floating_pointer_str);
 #endif
         if (!strncmp("_MP_", floating_pointer_str, strlen("_MP_")))
-            return (uintptr_t)p_floating_pointer_str;
+            return (FlatPtr)p_floating_pointer_str;
         p_floating_pointer_str += 16;
     }
-    return (uintptr_t) nullptr;
+    return (FlatPtr) nullptr;
 }
-uintptr_t MultiProcessorParser::search_floating_pointer_in_bios_area()
+FlatPtr MultiProcessorParser::search_floating_pointer_in_bios_area()
 {
     auto floating_pointer_region = MM.allocate_kernel_region(PhysicalAddress(page_base_of((u32)0xE0000)), PAGE_ROUND_UP(0xFFFFF - 0xE0000), "MultiProcessor Parser floating_pointer Finding #2", Region::Access::Read, false, true);
     char* p_floating_pointer_str = (char*)(PhysicalAddress(0xE0000).as_ptr());
@@ -160,10 +160,10 @@ uintptr_t MultiProcessorParser::search_floating_pointer_in_bios_area()
         dbg() << "MultiProcessor: Looking for floating pointer structure in BIOS area @ V0x " << String::format("%x", floating_pointer_str) << ", P0x" << String::format("%x", p_floating_pointer_str);
 #endif
         if (!strncmp("_MP_", floating_pointer_str, strlen("_MP_")))
-            return (uintptr_t)p_floating_pointer_str;
+            return (FlatPtr)p_floating_pointer_str;
         p_floating_pointer_str += 16;
     }
-    return (uintptr_t) nullptr;
+    return (FlatPtr) nullptr;
 }
 
 Vector<unsigned> MultiProcessorParser::get_pci_bus_ids()
diff --git a/Kernel/ACPI/MultiProcessorParser.h b/Kernel/ACPI/MultiProcessorParser.h
index 21b031d12c..1d035f749d 100644
--- a/Kernel/ACPI/MultiProcessorParser.h
+++ b/Kernel/ACPI/MultiProcessorParser.h
@@ -225,14 +225,14 @@ protected:
 
     Vector<unsigned> get_pci_bus_ids();
 
-    uintptr_t search_floating_pointer();
-    uintptr_t search_floating_pointer_in_ebda(u16 ebda_segment);
-    uintptr_t search_floating_pointer_in_bios_area();
-
-    uintptr_t m_floating_pointer;
-    uintptr_t m_configuration_table;
-    Vector<uintptr_t> m_io_interrupt_redirection_entries;
-    Vector<uintptr_t> m_bus_entries;
+    FlatPtr search_floating_pointer();
+    FlatPtr search_floating_pointer_in_ebda(u16 ebda_segment);
+    FlatPtr search_floating_pointer_in_bios_area();
+
+    FlatPtr m_floating_pointer;
+    FlatPtr m_configuration_table;
+    Vector<FlatPtr> m_io_interrupt_redirection_entries;
+    Vector<FlatPtr> m_bus_entries;
     bool m_operable;
 
     size_t m_configuration_table_length;
diff --git a/Kernel/Arch/i386/CPU.h b/Kernel/Arch/i386/CPU.h
index c9f59e3e40..80a08ebd79 100644
--- a/Kernel/Arch/i386/CPU.h
+++ b/Kernel/Arch/i386/CPU.h
@@ -33,7 +33,7 @@
 
 #define PAGE_SIZE 4096
 #define GENERIC_INTERRUPT_HANDLERS_COUNT 128
-#define PAGE_MASK ((uintptr_t)0xfffff000u)
+#define PAGE_MASK ((FlatPtr)0xfffff000u)
 
 namespace Kernel {
 
@@ -451,24 +451,24 @@ struct [[gnu::aligned(16)]] FPUState
     u8 buffer[512];
 };
 
-inline constexpr uintptr_t page_base_of(uintptr_t address)
+inline constexpr FlatPtr page_base_of(FlatPtr address)
 {
     return address & PAGE_MASK;
 }
 
-inline uintptr_t page_base_of(const void* address)
+inline FlatPtr page_base_of(const void* address)
 {
-    return page_base_of((uintptr_t)address);
+    return page_base_of((FlatPtr)address);
 }
 
-inline constexpr uintptr_t offset_in_page(uintptr_t address)
+inline constexpr FlatPtr offset_in_page(FlatPtr address)
 {
     return address & (~PAGE_MASK);
 }
 
-inline uintptr_t offset_in_page(const void* address)
+inline FlatPtr offset_in_page(const void* address)
 {
-    return offset_in_page((uintptr_t)address);
+    return offset_in_page((FlatPtr)address);
 }
 
 u32 read_cr3();
diff --git a/Kernel/Heap/kmalloc.cpp b/Kernel/Heap/kmalloc.cpp
index f068a38912..4b5358d80e 100644
--- a/Kernel/Heap/kmalloc.cpp
+++ b/Kernel/Heap/kmalloc.cpp
@@ -188,7 +188,7 @@ void kfree(void* ptr)
     ++g_kfree_call_count;
 
     auto* a = (AllocationHeader*)((((u8*)ptr) - sizeof(AllocationHeader)));
-    uintptr_t start = ((uintptr_t)a - (uintptr_t)BASE_PHYSICAL) / CHUNK_SIZE;
+    FlatPtr start = ((FlatPtr)a - (FlatPtr)BASE_PHYSICAL) / CHUNK_SIZE;
 
     for (size_t k = start; k < (start + a->allocation_size_in_chunks); ++k)
         alloc_map[k / 8] &= ~(1 << (k % 8));
diff --git a/Kernel/Net/E1000NetworkAdapter.cpp b/Kernel/Net/E1000NetworkAdapter.cpp
index 156df22c83..c89186630b 100644
--- a/Kernel/Net/E1000NetworkAdapter.cpp
+++ b/Kernel/Net/E1000NetworkAdapter.cpp
@@ -250,14 +250,14 @@ bool E1000NetworkAdapter::link_up()
 
 void E1000NetworkAdapter::initialize_rx_descriptors()
 {
-    auto ptr = (uintptr_t)kmalloc_eternal(sizeof(e1000_rx_desc) * number_of_rx_descriptors + 16);
+    auto ptr = (FlatPtr)kmalloc_eternal(sizeof(e1000_rx_desc) * number_of_rx_descriptors + 16);
     // Make sure it's 16-byte aligned.
     if (ptr % 16)
         ptr = (ptr + 16) - (ptr % 16);
     m_rx_descriptors = (e1000_rx_desc*)ptr;
     for (int i = 0; i < number_of_rx_descriptors; ++i) {
         auto& descriptor = m_rx_descriptors[i];
-        auto addr = (uintptr_t)kmalloc_eternal(8192 + 16);
+        auto addr = (FlatPtr)kmalloc_eternal(8192 + 16);
         if (addr % 16)
             addr = (addr + 16) - (addr % 16);
         descriptor.addr = addr - 0xc0000000;
@@ -275,14 +275,14 @@ void E1000NetworkAdapter::initialize_rx_descriptors()
 
 void E1000NetworkAdapter::initialize_tx_descriptors()
 {
-    auto ptr = (uintptr_t)kmalloc_eternal(sizeof(e1000_tx_desc) * number_of_tx_descriptors + 16);
+    auto ptr = (FlatPtr)kmalloc_eternal(sizeof(e1000_tx_desc) * number_of_tx_descriptors + 16);
     // Make sure it's 16-byte aligned.
     if (ptr % 16)
         ptr = (ptr + 16) - (ptr % 16);
     m_tx_descriptors = (e1000_tx_desc*)ptr;
     for (int i = 0; i < number_of_tx_descriptors; ++i) {
         auto& descriptor = m_tx_descriptors[i];
-        auto addr = (uintptr_t)kmalloc_eternal(8192 + 16);
+        auto addr = (FlatPtr)kmalloc_eternal(8192 + 16);
         if (addr % 16)
             addr = (addr + 16) - (addr % 16);
         descriptor.addr = addr - 0xc0000000;
diff --git a/Kernel/Net/RTL8139NetworkAdapter.cpp b/Kernel/Net/RTL8139NetworkAdapter.cpp
index 0a3bdd0621..83b48929a4 100644
--- a/Kernel/Net/RTL8139NetworkAdapter.cpp
+++ b/Kernel/Net/RTL8139NetworkAdapter.cpp
@@ -154,16 +154,16 @@ RTL8139NetworkAdapter::RTL8139NetworkAdapter(PCI::Address address, u8 irq)
     // we add space to account for overhang from the last packet - the rtl8139
     // can optionally guarantee that packets will be contiguous by
     // purposefully overrunning the rx buffer
-    m_rx_buffer_addr = (uintptr_t)virtual_to_low_physical(kmalloc_aligned(RX_BUFFER_SIZE + PACKET_SIZE_MAX, 16));
+    m_rx_buffer_addr = (FlatPtr)virtual_to_low_physical(kmalloc_aligned(RX_BUFFER_SIZE + PACKET_SIZE_MAX, 16));
     klog() << "RTL8139: RX buffer: " << PhysicalAddress(m_rx_buffer_addr);
 
-    auto tx_buffer_addr = (uintptr_t)virtual_to_low_physical(kmalloc_aligned(TX_BUFFER_SIZE * 4, 16));
+    auto tx_buffer_addr = (FlatPtr)virtual_to_low_physical(kmalloc_aligned(TX_BUFFER_SIZE * 4, 16));
     for (int i = 0; i < RTL8139_TX_BUFFER_COUNT; i++) {
         m_tx_buffer_addr[i] = tx_buffer_addr + TX_BUFFER_SIZE * i;
         klog() << "RTL8139: TX buffer " << i << ": "  << PhysicalAddress(m_tx_buffer_addr[i]);
     }
 
-    m_packet_buffer = (uintptr_t)kmalloc(PACKET_SIZE_MAX);
+    m_packet_buffer = (FlatPtr)kmalloc(PACKET_SIZE_MAX);
 
     reset();
 
diff --git a/Kernel/PerformanceEventBuffer.cpp b/Kernel/PerformanceEventBuffer.cpp
index 2a83f45a3e..857ed8d7f7 100644
--- a/Kernel/PerformanceEventBuffer.cpp
+++ b/Kernel/PerformanceEventBuffer.cpp
@@ -37,7 +37,7 @@ PerformanceEventBuffer::PerformanceEventBuffer()
 {
 }
 
-KResult PerformanceEventBuffer::append(int type, uintptr_t arg1, uintptr_t arg2)
+KResult PerformanceEventBuffer::append(int type, FlatPtr arg1, FlatPtr arg2)
 {
     if (count() >= capacity())
         return KResult(-ENOBUFS);
@@ -63,17 +63,17 @@ KResult PerformanceEventBuffer::append(int type, uintptr_t arg1, uintptr_t arg2)
         return KResult(-EINVAL);
     }
 
-    uintptr_t ebp;
+    FlatPtr ebp;
     asm volatile("movl %%ebp, %%eax"
                  : "=a"(ebp));
-    //copy_from_user(&ebp, (uintptr_t*)current->get_register_dump_from_stack().ebp);
-    Vector<uintptr_t> backtrace;
+    //copy_from_user(&ebp, (FlatPtr*)current->get_register_dump_from_stack().ebp);
+    Vector<FlatPtr> backtrace;
     {
         SmapDisabler disabler;
         backtrace = Thread::current->raw_backtrace(ebp);
     }
-    event.stack_size = min(sizeof(event.stack) / sizeof(uintptr_t), static_cast<size_t>(backtrace.size()));
-    memcpy(event.stack, backtrace.data(), event.stack_size * sizeof(uintptr_t));
+    event.stack_size = min(sizeof(event.stack) / sizeof(FlatPtr), static_cast<size_t>(backtrace.size()));
+    memcpy(event.stack, backtrace.data(), event.stack_size * sizeof(FlatPtr));
 
 #ifdef VERY_DEBUG
     for (size_t i = 0; i < event.stack_size; ++i)
diff --git a/Kernel/PerformanceEventBuffer.h b/Kernel/PerformanceEventBuffer.h
index 5e5f15ff4e..f83d6f361b 100644
--- a/Kernel/PerformanceEventBuffer.h
+++ b/Kernel/PerformanceEventBuffer.h
@@ -34,13 +34,13 @@ namespace Kernel {
 struct [[gnu::packed]] MallocPerformanceEvent
 {
     size_t size;
-    uintptr_t ptr;
+    FlatPtr ptr;
 };
 
 struct [[gnu::packed]] FreePerformanceEvent
 {
     size_t size;
-    uintptr_t ptr;
+    FlatPtr ptr;
 };
 
 struct [[gnu::packed]] PerformanceEvent
@@ -52,14 +52,14 @@ struct [[gnu::packed]] PerformanceEvent
         MallocPerformanceEvent malloc;
         FreePerformanceEvent free;
     } data;
-    uintptr_t stack[32];
+    FlatPtr stack[32];
 };
 
 class PerformanceEventBuffer {
 public:
     PerformanceEventBuffer();
 
-    KResult append(int type, uintptr_t arg1, uintptr_t arg2);
+    KResult append(int type, FlatPtr arg1, FlatPtr arg2);
 
     size_t capacity() const { return m_buffer.size() / sizeof(PerformanceEvent); }
     size_t count() const { return m_count; }
diff --git a/Kernel/Process.cpp b/Kernel/Process.cpp
index 98e17eeca0..eb156b0731 100644
--- a/Kernel/Process.cpp
+++ b/Kernel/Process.cpp
@@ -393,7 +393,7 @@ void* Process::sys$mmap(const Syscall::SC_mmap_params* user_params)
 
     if (size == 0)
         return (void*)-EINVAL;
-    if ((uintptr_t)addr & ~PAGE_MASK)
+    if ((FlatPtr)addr & ~PAGE_MASK)
         return (void*)-EINVAL;
 
     bool map_shared = flags & MAP_SHARED;
@@ -1324,7 +1324,7 @@ Process* Process::create_user_process(Thread*& first_thread, const String& path,
 Process* Process::create_kernel_process(Thread*& first_thread, String&& name, void (*e)())
 {
     auto* process = new Process(first_thread, move(name), (uid_t)0, (gid_t)0, (pid_t)0, Ring0);
-    first_thread->tss().eip = (uintptr_t)e;
+    first_thread->tss().eip = (FlatPtr)e;
 
     if (process->pid() != 0) {
         InterruptDisabler disabler;
@@ -1474,7 +1474,7 @@ int Process::sys$sigreturn(RegisterState& registers)
     stack_ptr++;
 
     //pop edi, esi, ebp, esp, ebx, edx, ecx and eax
-    memcpy(&registers.edi, stack_ptr, 8 * sizeof(uintptr_t));
+    memcpy(&registers.edi, stack_ptr, 8 * sizeof(FlatPtr));
     stack_ptr += 8;
 
     registers.eip = *stack_ptr;
@@ -3740,13 +3740,13 @@ int Process::sys$create_thread(void* (*entry)(void*), void* argument, const Sysc
     thread->set_joinable(is_thread_joinable);
 
     auto& tss = thread->tss();
-    tss.eip = (uintptr_t)entry;
+    tss.eip = (FlatPtr)entry;
     tss.eflags = 0x0202;
     tss.cr3 = page_directory().cr3();
     tss.esp = user_stack_address;
 
     // NOTE: The stack needs to be 16-byte aligned.
-    thread->push_value_on_stack((uintptr_t)argument);
+    thread->push_value_on_stack((FlatPtr)argument);
     thread->push_value_on_stack(0);
 
     thread->make_thread_specific_region({});
@@ -4531,7 +4531,7 @@ Thread& Process::any_thread()
 
 WaitQueue& Process::futex_queue(i32* userspace_address)
 {
-    auto& queue = m_futex_queues.ensure((uintptr_t)userspace_address);
+    auto& queue = m_futex_queues.ensure((FlatPtr)userspace_address);
     if (!queue)
         queue = make<WaitQueue>();
     return *queue;
@@ -4793,7 +4793,7 @@ int Process::sys$unveil(const Syscall::SC_unveil_params* user_params)
     return 0;
 }
 
-int Process::sys$perf_event(int type, uintptr_t arg1, uintptr_t arg2)
+int Process::sys$perf_event(int type, FlatPtr arg1, FlatPtr arg2)
 {
     if (!m_perf_event_buffer)
         m_perf_event_buffer = make<PerformanceEventBuffer>();
diff --git a/Kernel/Process.h b/Kernel/Process.h
index 3aa698cf8e..b050c1cf28 100644
--- a/Kernel/Process.h
+++ b/Kernel/Process.h
@@ -297,7 +297,7 @@ public:
     int sys$chroot(const char* path, size_t path_length, int mount_flags);
     int sys$pledge(const Syscall::SC_pledge_params*);
     int sys$unveil(const Syscall::SC_unveil_params*);
-    int sys$perf_event(int type, uintptr_t arg1, uintptr_t arg2);
+    int sys$perf_event(int type, FlatPtr arg1, FlatPtr arg2);
 
     template<bool sockname, typename Params>
     int get_sock_or_peer_name(const Params&);
diff --git a/Kernel/Thread.cpp b/Kernel/Thread.cpp
index 10d880c331..4379cad746 100644
--- a/Kernel/Thread.cpp
+++ b/Kernel/Thread.cpp
@@ -625,10 +625,10 @@ void Thread::set_default_signal_dispositions()
     m_signal_action_data[SIGWINCH].handler_or_sigaction = VirtualAddress(SIG_IGN);
 }
 
-void Thread::push_value_on_stack(uintptr_t value)
+void Thread::push_value_on_stack(FlatPtr value)
 {
     m_tss.esp -= 4;
-    uintptr_t* stack_ptr = (uintptr_t*)m_tss.esp;
+    FlatPtr* stack_ptr = (FlatPtr*)m_tss.esp;
     copy_to_user(stack_ptr, &value);
 }
 
@@ -681,9 +681,9 @@ u32 Thread::make_userspace_stack_for_main_thread(Vector<String> arguments, Vecto
     };
 
     // NOTE: The stack needs to be 16-byte aligned.
-    push_on_new_stack((uintptr_t)env);
-    push_on_new_stack((uintptr_t)argv);
-    push_on_new_stack((uintptr_t)argc);
+    push_on_new_stack((FlatPtr)env);
+    push_on_new_stack((FlatPtr)argv);
+    push_on_new_stack((FlatPtr)argc);
     push_on_new_stack(0);
     return new_esp;
 }
@@ -797,20 +797,20 @@ String Thread::backtrace_impl() const
     auto elf_bundle = process.elf_bundle();
     ProcessPagingScope paging_scope(process);
 
-    uintptr_t stack_ptr = start_frame;
+    FlatPtr stack_ptr = start_frame;
     for (;;) {
         if (!process.validate_read_from_kernel(VirtualAddress(stack_ptr), sizeof(void*) * 2))
             break;
-        uintptr_t retaddr;
+        FlatPtr retaddr;
 
-        if (is_user_range(VirtualAddress(stack_ptr), sizeof(uintptr_t) * 2)) {
-            copy_from_user(&retaddr, &((uintptr_t*)stack_ptr)[1]);
+        if (is_user_range(VirtualAddress(stack_ptr), sizeof(FlatPtr) * 2)) {
+            copy_from_user(&retaddr, &((FlatPtr*)stack_ptr)[1]);
             recognized_symbols.append({ retaddr, ksymbolicate(retaddr) });
-            copy_from_user(&stack_ptr, (uintptr_t*)stack_ptr);
+            copy_from_user(&stack_ptr, (FlatPtr*)stack_ptr);
         } else {
-            memcpy(&retaddr, &((uintptr_t*)stack_ptr)[1], sizeof(uintptr_t));
+            memcpy(&retaddr, &((FlatPtr*)stack_ptr)[1], sizeof(FlatPtr));
             recognized_symbols.append({ retaddr, ksymbolicate(retaddr) });
-            memcpy(&stack_ptr, (uintptr_t*)stack_ptr, sizeof(uintptr_t));
+            memcpy(&stack_ptr, (FlatPtr*)stack_ptr, sizeof(FlatPtr));
         }
     }
 
@@ -822,15 +822,15 @@ String Thread::backtrace_impl() const
     return builder.to_string();
 }
 
-Vector<uintptr_t> Thread::raw_backtrace(uintptr_t ebp) const
+Vector<FlatPtr> Thread::raw_backtrace(FlatPtr ebp) const
 {
     InterruptDisabler disabler;
     auto& process = const_cast<Process&>(this->process());
     ProcessPagingScope paging_scope(process);
-    Vector<uintptr_t, Profiling::max_stack_frame_count> backtrace;
+    Vector<FlatPtr, Profiling::max_stack_frame_count> backtrace;
     backtrace.append(ebp);
-    for (uintptr_t* stack_ptr = (uintptr_t*)ebp; process.validate_read_from_kernel(VirtualAddress(stack_ptr), sizeof(uintptr_t) * 2) && MM.can_read_without_faulting(process, VirtualAddress(stack_ptr), sizeof(uintptr_t) * 2); stack_ptr = (uintptr_t*)*stack_ptr) {
-        uintptr_t retaddr = stack_ptr[1];
+    for (FlatPtr* stack_ptr = (FlatPtr*)ebp; process.validate_read_from_kernel(VirtualAddress(stack_ptr), sizeof(FlatPtr) * 2) && MM.can_read_without_faulting(process, VirtualAddress(stack_ptr), sizeof(FlatPtr) * 2); stack_ptr = (FlatPtr*)*stack_ptr) {
+        FlatPtr retaddr = stack_ptr[1];
         backtrace.append(retaddr);
         if (backtrace.size() == Profiling::max_stack_frame_count)
             break;
diff --git a/Kernel/Thread.h b/Kernel/Thread.h
index f59aeee95b..1d0e9e0e50 100644
--- a/Kernel/Thread.h
+++ b/Kernel/Thread.h
@@ -97,7 +97,7 @@ public:
     const Process& process() const { return m_process; }
 
     String backtrace(ProcessInspectionHandle&) const;
-    Vector<uintptr_t> raw_backtrace(uintptr_t ebp) const;
+    Vector<FlatPtr> raw_backtrace(FlatPtr ebp) const;
 
     const String& name() const { return m_name; }
     void set_name(StringView s) { m_name = s; }
@@ -360,7 +360,7 @@ public:
     FPUState& fpu_state() { return *m_fpu_state; }
 
     void set_default_signal_dispositions();
-    void push_value_on_stack(uintptr_t);
+    void push_value_on_stack(FlatPtr);
 
     u32 make_userspace_stack_for_main_thread(Vector<String> arguments, Vector<String> environment);
 
diff --git a/Kernel/VM/MemoryManager.cpp b/Kernel/VM/MemoryManager.cpp
index 10cdbfca85..fbfe47a6a9 100644
--- a/Kernel/VM/MemoryManager.cpp
+++ b/Kernel/VM/MemoryManager.cpp
@@ -41,9 +41,9 @@
 //#define MM_DEBUG
 //#define PAGE_FAULT_DEBUG
 
-extern uintptr_t start_of_kernel_text;
-extern uintptr_t start_of_kernel_data;
-extern uintptr_t end_of_kernel_bss;
+extern FlatPtr start_of_kernel_text;
+extern FlatPtr start_of_kernel_data;
+extern FlatPtr end_of_kernel_bss;
 
 namespace Kernel {
 
@@ -72,14 +72,14 @@ MemoryManager::~MemoryManager()
 void MemoryManager::protect_kernel_image()
 {
     // Disable writing to the kernel text and rodata segments.
-    for (size_t i = (uintptr_t)&start_of_kernel_text; i < (uintptr_t)&start_of_kernel_data; i += PAGE_SIZE) {
+    for (size_t i = (FlatPtr)&start_of_kernel_text; i < (FlatPtr)&start_of_kernel_data; i += PAGE_SIZE) {
         auto& pte = ensure_pte(kernel_page_directory(), VirtualAddress(i));
         pte.set_writable(false);
     }
 
     if (g_cpu_supports_nx) {
         // Disable execution of the kernel data and bss segments.
-        for (size_t i = (uintptr_t)&start_of_kernel_data; i < (uintptr_t)&end_of_kernel_bss; i += PAGE_SIZE) {
+        for (size_t i = (FlatPtr)&start_of_kernel_data; i < (FlatPtr)&end_of_kernel_bss; i += PAGE_SIZE) {
             auto& pte = ensure_pte(kernel_page_directory(), VirtualAddress(i));
             pte.set_execute_disabled(true);
         }
@@ -104,7 +104,7 @@ void MemoryManager::setup_low_identity_mapping()
     if (g_cpu_supports_nx)
         pde_zero.set_execute_disabled(true);
 
-    for (uintptr_t offset = (1 * MB); offset < (2 * MB); offset += PAGE_SIZE) {
+    for (FlatPtr offset = (1 * MB); offset < (2 * MB); offset += PAGE_SIZE) {
         auto& page_table_page = m_low_page_table;
         auto& pte = quickmap_pt(page_table_page->paddr())[offset / PAGE_SIZE];
         pte.set_physical_page_base(offset);
@@ -132,7 +132,7 @@ void MemoryManager::parse_memory_map()
         if ((mmap->addr + mmap->len) > 0xffffffff)
             continue;
 
-        auto diff = (uintptr_t)mmap->addr % PAGE_SIZE;
+        auto diff = (FlatPtr)mmap->addr % PAGE_SIZE;
         if (diff != 0) {
             klog() << "MM: got an unaligned region base from the bootloader; correcting " << String::format("%p", mmap->addr) << " by " << diff << " bytes";
             diff = PAGE_SIZE - diff;
@@ -149,7 +149,7 @@ void MemoryManager::parse_memory_map()
         }
 
 #ifdef MM_DEBUG
-        klog() << "MM: considering memory at " << String::format("%p", (uintptr_t)mmap->addr) << " - " << String::format("%p", (uintptr_t)(mmap->addr + mmap->len));
+        klog() << "MM: considering memory at " << String::format("%p", (FlatPtr)mmap->addr) << " - " << String::format("%p", (FlatPtr)(mmap->addr + mmap->len));
 #endif
 
         for (size_t page_base = mmap->addr; page_base < (mmap->addr + mmap->len); page_base += PAGE_SIZE) {
@@ -196,7 +196,7 @@ const PageTableEntry* MemoryManager::pte(const PageDirectory& page_directory, Vi
     if (!pde.is_present())
         return nullptr;
 
-    return &quickmap_pt(PhysicalAddress((uintptr_t)pde.page_table_base()))[page_table_index];
+    return &quickmap_pt(PhysicalAddress((FlatPtr)pde.page_table_base()))[page_table_index];
 }
 
 PageTableEntry& MemoryManager::ensure_pte(PageDirectory& page_directory, VirtualAddress vaddr)
@@ -224,7 +224,7 @@ PageTableEntry& MemoryManager::ensure_pte(PageDirectory& page_directory, Virtual
         page_directory.m_physical_pages.set(page_directory_index, move(page_table));
     }
 
-    return quickmap_pt(PhysicalAddress((uintptr_t)pde.page_table_base()))[page_table_index];
+    return quickmap_pt(PhysicalAddress((FlatPtr)pde.page_table_base()))[page_table_index];
 }
 
 void MemoryManager::initialize()
diff --git a/Kernel/VM/PageDirectory.cpp b/Kernel/VM/PageDirectory.cpp
index aff510ce72..67a4f96ffa 100644
--- a/Kernel/VM/PageDirectory.cpp
+++ b/Kernel/VM/PageDirectory.cpp
@@ -32,9 +32,9 @@
 
 namespace Kernel {
 
-static const uintptr_t userspace_range_base = 0x00800000;
-static const uintptr_t userspace_range_ceiling = 0xbe000000;
-static const uintptr_t kernelspace_range_base = 0xc0800000;
+static const FlatPtr userspace_range_base = 0x00800000;
+static const FlatPtr userspace_range_ceiling = 0xbe000000;
+static const FlatPtr kernelspace_range_base = 0xc0800000;
 
 static HashMap<u32, PageDirectory*>& cr3_map()
 {
@@ -60,9 +60,9 @@ PageDirectory::PageDirectory()
     m_range_allocator.initialize_with_range(VirtualAddress(0xc0800000), 0x3f000000);
 
     // Adopt the page tables already set up by boot.S
-    PhysicalAddress boot_pdpt_paddr(virtual_to_low_physical((uintptr_t)boot_pdpt));
-    PhysicalAddress boot_pd0_paddr(virtual_to_low_physical((uintptr_t)boot_pd0));
-    PhysicalAddress boot_pd3_paddr(virtual_to_low_physical((uintptr_t)boot_pd3));
+    PhysicalAddress boot_pdpt_paddr(virtual_to_low_physical((FlatPtr)boot_pdpt));
+    PhysicalAddress boot_pd0_paddr(virtual_to_low_physical((FlatPtr)boot_pd0));
+    PhysicalAddress boot_pd3_paddr(virtual_to_low_physical((FlatPtr)boot_pd3));
     klog() << "MM: boot_pdpt @ " << boot_pdpt_paddr;
     klog() << "MM: boot_pd0 @ " << boot_pd0_paddr;
     klog() << "MM: boot_pd3 @ " << boot_pd3_paddr;
diff --git a/Kernel/VM/PhysicalRegion.cpp b/Kernel/VM/PhysicalRegion.cpp
index 558d8a51c4..1a0880bdff 100644
--- a/Kernel/VM/PhysicalRegion.cpp
+++ b/Kernel/VM/PhysicalRegion.cpp
@@ -105,9 +105,9 @@ void PhysicalRegion::return_page_at(PhysicalAddress addr)
 
     ptrdiff_t local_offset = addr.get() - m_lower.get();
     ASSERT(local_offset >= 0);
-    ASSERT((uintptr_t)local_offset < (uintptr_t)(m_pages * PAGE_SIZE));
+    ASSERT((FlatPtr)local_offset < (FlatPtr)(m_pages * PAGE_SIZE));
 
-    auto page = (uintptr_t)local_offset / PAGE_SIZE;
+    auto page = (FlatPtr)local_offset / PAGE_SIZE;
     if (page < m_last)
         m_last = page;
 
diff --git a/Kernel/VM/RangeAllocator.cpp b/Kernel/VM/RangeAllocator.cpp
index 6ceee3ce68..62f2350ef9 100644
--- a/Kernel/VM/RangeAllocator.cpp
+++ b/Kernel/VM/RangeAllocator.cpp
@@ -112,8 +112,8 @@ Range RangeAllocator::allocate_anywhere(size_t size, size_t alignment)
         if (available_range.size() < (effective_size + alignment))
             continue;
 
-        uintptr_t initial_base = available_range.base().offset(offset_from_effective_base).get();
-        uintptr_t aligned_base = round_up_to_power_of_two(initial_base, alignment);
+        FlatPtr initial_base = available_range.base().offset(offset_from_effective_base).get();
+        FlatPtr aligned_base = round_up_to_power_of_two(initial_base, alignment);
 
         Range allocated_range(VirtualAddress(aligned_base), size);
         if (available_range == allocated_range) {
diff --git a/Libraries/LibBareMetal/Memory/PhysicalAddress.h b/Libraries/LibBareMetal/Memory/PhysicalAddress.h
index 02594b3389..e982cece9b 100644
--- a/Libraries/LibBareMetal/Memory/PhysicalAddress.h
+++ b/Libraries/LibBareMetal/Memory/PhysicalAddress.h
@@ -32,15 +32,15 @@
 class PhysicalAddress {
 public:
     PhysicalAddress() {}
-    explicit PhysicalAddress(uintptr_t address)
+    explicit PhysicalAddress(FlatPtr address)
         : m_address(address)
     {
     }
 
-    PhysicalAddress offset(uintptr_t o) const { return PhysicalAddress(m_address + o); }
-    uintptr_t get() const { return m_address; }
-    void set(uintptr_t address) { m_address = address; }
-    void mask(uintptr_t m) { m_address &= m; }
+    PhysicalAddress offset(FlatPtr o) const { return PhysicalAddress(m_address + o); }
+    FlatPtr get() const { return m_address; }
+    void set(FlatPtr address) { m_address = address; }
+    void mask(FlatPtr m) { m_address &= m; }
 
     bool is_null() const { return m_address == 0; }
 
@@ -58,7 +58,7 @@ public:
     bool operator<=(const PhysicalAddress& other) const { return m_address <= other.m_address; }
 
 private:
-    uintptr_t m_address { 0 };
+    FlatPtr m_address { 0 };
 };
 
 inline const LogStream& operator<<(const LogStream& stream, PhysicalAddress value)
diff --git a/Libraries/LibBareMetal/Memory/VirtualAddress.h b/Libraries/LibBareMetal/Memory/VirtualAddress.h
index 92dfb6698d..2c82cb0d40 100644
--- a/Libraries/LibBareMetal/Memory/VirtualAddress.h
+++ b/Libraries/LibBareMetal/Memory/VirtualAddress.h
@@ -32,23 +32,23 @@
 class VirtualAddress {
 public:
     VirtualAddress() {}
-    explicit VirtualAddress(uintptr_t address)
+    explicit VirtualAddress(FlatPtr address)
         : m_address(address)
     {
     }
 
     explicit VirtualAddress(const void* address)
-        : m_address((uintptr_t)address)
+        : m_address((FlatPtr)address)
     {
     }
 
     bool is_null() const { return m_address == 0; }
     bool is_page_aligned() const { return (m_address & 0xfff) == 0; }
 
-    VirtualAddress offset(uintptr_t o) const { return VirtualAddress(m_address + o); }
-    uintptr_t get() const { return m_address; }
-    void set(uintptr_t address) { m_address = address; }
-    void mask(uintptr_t m) { m_address &= m; }
+    VirtualAddress offset(FlatPtr o) const { return VirtualAddress(m_address + o); }
+    FlatPtr get() const { return m_address; }
+    void set(FlatPtr address) { m_address = address; }
+    void mask(FlatPtr m) { m_address &= m; }
 
     bool operator<=(const VirtualAddress& other) const { return m_address <= other.m_address; }
     bool operator>=(const VirtualAddress& other) const { return m_address >= other.m_address; }
@@ -63,7 +63,7 @@ public:
     VirtualAddress page_base() const { return VirtualAddress(m_address & 0xfffff000); }
 
 private:
-    uintptr_t m_address { 0 };
+    FlatPtr m_address { 0 };
 };
 
 inline VirtualAddress operator-(const VirtualAddress& a, const VirtualAddress& b)
diff --git a/Libraries/LibC/malloc.cpp b/Libraries/LibC/malloc.cpp
index 86f6e8bf7a..0c1ddd388b 100644
--- a/Libraries/LibC/malloc.cpp
+++ b/Libraries/LibC/malloc.cpp
@@ -294,7 +294,7 @@ static void free_impl(void* ptr)
 
     LOCKER(malloc_lock());
 
-    void* block_base = (void*)((uintptr_t)ptr & block_mask);
+    void* block_base = (void*)((FlatPtr)ptr & block_mask);
     size_t magic = *(size_t*)block_base;
 
     if (magic == MAGIC_BIGALLOC_HEADER) {
@@ -372,14 +372,14 @@ void* malloc(size_t size)
 {
     void* ptr = malloc_impl(size);
     if (s_profiling)
-        perf_event(PERF_EVENT_MALLOC, size, reinterpret_cast<uintptr_t>(ptr));
+        perf_event(PERF_EVENT_MALLOC, size, reinterpret_cast<FlatPtr>(ptr));
     return ptr;
 }
 
 void free(void* ptr)
 {
     if (s_profiling)
-        perf_event(PERF_EVENT_FREE, reinterpret_cast<uintptr_t>(ptr), 0);
+        perf_event(PERF_EVENT_FREE, reinterpret_cast<FlatPtr>(ptr), 0);
     free_impl(ptr);
 }
 
@@ -396,7 +396,7 @@ size_t malloc_size(void* ptr)
     if (!ptr)
         return 0;
     LOCKER(malloc_lock());
-    void* page_base = (void*)((uintptr_t)ptr & block_mask);
+    void* page_base = (void*)((FlatPtr)ptr & block_mask);
     auto* header = (const CommonHeader*)page_base;
     auto size = header->m_size;
     if (header->m_magic == MAGIC_BIGALLOC_HEADER)
diff --git a/Libraries/LibC/serenity.cpp b/Libraries/LibC/serenity.cpp
index a75ab55791..ce665489b8 100644
--- a/Libraries/LibC/serenity.cpp
+++ b/Libraries/LibC/serenity.cpp
@@ -79,7 +79,7 @@ int purge(int mode)
     __RETURN_WITH_ERRNO(rc, rc, -1);
 }
 
-int perf_event(int type, uintptr_t arg1, uintptr_t arg2)
+int perf_event(int type, uintptr_t arg1, FlatPtr arg2)
 {
     int rc = syscall(SC_perf_event, type, arg1, arg2);
     __RETURN_WITH_ERRNO(rc, rc, -1);
diff --git a/Libraries/LibCore/EventLoop.cpp b/Libraries/LibCore/EventLoop.cpp
index 74532d6b44..c79f73e7a4 100644
--- a/Libraries/LibCore/EventLoop.cpp
+++ b/Libraries/LibCore/EventLoop.cpp
@@ -164,9 +164,9 @@ public:
         }
 
         if (type == "SetInspectedObject") {
-            auto address = request.get("address").to_number<uintptr_t>();
+            auto address = request.get("address").to_number<FlatPtr>();
             for (auto& object : Object::all_objects()) {
-                if ((uintptr_t)&object == address) {
+                if ((FlatPtr)&object == address) {
                     if (m_inspected_object)
                         m_inspected_object->decrement_inspector_count({});
                     m_inspected_object = object.make_weak_ptr();
@@ -178,9 +178,9 @@ public:
         }
 
         if (type == "SetProperty") {
-            auto address = request.get("address").to_number<uintptr_t>();
+            auto address = request.get("address").to_number<FlatPtr>();
             for (auto& object : Object::all_objects()) {
-                if ((uintptr_t)&object == address) {
+                if ((FlatPtr)&object == address) {
                     bool success = object.set_property(request.get("name").to_string(), request.get("value"));
                     JsonObject response;
                     response.set("type", "SetProperty");
diff --git a/Libraries/LibCore/Object.cpp b/Libraries/LibCore/Object.cpp
index c503a23d02..1321230317 100644
--- a/Libraries/LibCore/Object.cpp
+++ b/Libraries/LibCore/Object.cpp
@@ -168,9 +168,9 @@ void Object::deferred_invoke(Function<void(Object&)> invokee)
 void Object::save_to(JsonObject& json)
 {
     json.set("class_name", class_name());
-    json.set("address", (uintptr_t)this);
+    json.set("address", (FlatPtr)this);
     json.set("name", name());
-    json.set("parent", (uintptr_t)parent());
+    json.set("parent", (FlatPtr)parent());
 }
 
 bool Object::set_property(const StringView& name, const JsonValue& value)
diff --git a/Libraries/LibELF/ELFDynamicObject.h b/Libraries/LibELF/ELFDynamicObject.h
index 80eb9db281..8618d721d0 100644
--- a/Libraries/LibELF/ELFDynamicObject.h
+++ b/Libraries/LibELF/ELFDynamicObject.h
@@ -228,32 +228,32 @@ private:
     unsigned m_symbol_count { 0 };
 
     // Begin Section information collected from DT_* entries
-    uintptr_t m_init_offset { 0 };
-    uintptr_t m_fini_offset { 0 };
+    FlatPtr m_init_offset { 0 };
+    FlatPtr m_fini_offset { 0 };
 
-    uintptr_t m_init_array_offset { 0 };
+    FlatPtr m_init_array_offset { 0 };
     size_t m_init_array_size { 0 };
-    uintptr_t m_fini_array_offset { 0 };
+    FlatPtr m_fini_array_offset { 0 };
     size_t m_fini_array_size { 0 };
 
-    uintptr_t m_hash_table_offset { 0 };
+    FlatPtr m_hash_table_offset { 0 };
 
-    uintptr_t m_string_table_offset { 0 };
+    FlatPtr m_string_table_offset { 0 };
     size_t m_size_of_string_table { 0 };
-    uintptr_t m_symbol_table_offset { 0 };
+    FlatPtr m_symbol_table_offset { 0 };
     size_t m_size_of_symbol_table_entry { 0 };
 
     Elf32_Sword m_procedure_linkage_table_relocation_type { -1 };
-    uintptr_t m_plt_relocation_offset_location { 0 }; // offset of PLT relocations, at end of relocations
+    FlatPtr m_plt_relocation_offset_location { 0 }; // offset of PLT relocations, at end of relocations
     size_t m_size_of_plt_relocation_entry_list { 0 };
-    uintptr_t m_procedure_linkage_table_offset { 0 };
+    FlatPtr m_procedure_linkage_table_offset { 0 };
 
     // NOTE: We'll only ever either RELA or REL entries, not both (thank god)
     // NOTE: The x86 ABI will only ever genrerate REL entries.
     size_t m_number_of_relocations { 0 };
     size_t m_size_of_relocation_entry { 0 };
     size_t m_size_of_relocation_table { 0 };
-    uintptr_t m_relocation_table_offset { 0 };
+    FlatPtr m_relocation_table_offset { 0 };
 
     // DT_FLAGS
     Elf32_Word m_dt_flags { 0 };
diff --git a/Libraries/LibGUI/CppSyntaxHighlighter.cpp b/Libraries/LibGUI/CppSyntaxHighlighter.cpp
index acee7903aa..3f1d5c4340 100644
--- a/Libraries/LibGUI/CppSyntaxHighlighter.cpp
+++ b/Libraries/LibGUI/CppSyntaxHighlighter.cpp
@@ -77,7 +77,7 @@ void CppSyntaxHighlighter::highlight_matching_token_pair()
         bool forward = direction == Direction::Forward;
         for (forward ? ++i : --i; forward ? (i < document.spans().size()) : (i >= 0); forward ? ++i : --i) {
             auto& span = document.spans().at(i);
-            auto span_token_type = (CppToken::Type)((uintptr_t)span.data);
+            auto span_token_type = (CppToken::Type)((FlatPtr)span.data);
             if (span_token_type == not_type) {
                 ++nesting_level;
             } else if (span_token_type == type) {
@@ -116,7 +116,7 @@ void CppSyntaxHighlighter::highlight_matching_token_pair()
 
     for (size_t i = 0; i < document.spans().size(); ++i) {
         auto& span = const_cast<GUI::TextDocumentSpan&>(document.spans().at(i));
-        auto token_type = (CppToken::Type)((uintptr_t)span.data);
+        auto token_type = (CppToken::Type)((FlatPtr)span.data);
 
         for (auto& pair : pairs) {
             if (token_type == pair.open && span.range.start() == m_editor->cursor()) {
diff --git a/Libraries/LibGUI/Layout.cpp b/Libraries/LibGUI/Layout.cpp
index 38be0a87e1..71c37e9369 100644
--- a/Libraries/LibGUI/Layout.cpp
+++ b/Libraries/LibGUI/Layout.cpp
@@ -138,7 +138,7 @@ void Layout::save_to(JsonObject& json)
         JsonObject entry_object;
         if (entry.type == Entry::Type::Widget) {
             entry_object.set("type", "Widget");
-            entry_object.set("widget", (uintptr_t)entry.widget.ptr());
+            entry_object.set("widget", (FlatPtr)entry.widget.ptr());
         } else if (entry.type == Entry::Type::Spacer) {
             entry_object.set("type", "Spacer");
         } else {
diff --git a/Userland/syscall.cpp b/Userland/syscall.cpp
index 0ccb7edd49..1c826c2a52 100644
--- a/Userland/syscall.cpp
+++ b/Userland/syscall.cpp
@@ -46,10 +46,10 @@ Syscall::Function syscall_table[] = {
     ENUMERATE_SYSCALLS
 };
 
-uintptr_t arg[SC_NARG];
+FlatPtr arg[SC_NARG];
 char buf[BUFSIZ];
 
-uintptr_t parse(char* s);
+FlatPtr parse(char* s);
 
 int main(int argc, char** argv)
 {
@@ -104,13 +104,13 @@ int main(int argc, char** argv)
     return -1;
 }
 
-uintptr_t parse(char* s)
+FlatPtr parse(char* s)
 {
     char* t;
-    uintptr_t l;
+    FlatPtr l;
 
     if (strcmp(s, "buf") == 0) {
-        return (uintptr_t)buf;
+        return (FlatPtr)buf;
     }
 
     l = strtoul(s, &t, 0);
@@ -118,5 +118,5 @@ uintptr_t parse(char* s)
         return l;
     }
 
-    return (uintptr_t)s;
+    return (FlatPtr)s;
 }