Kernel: Clean up IDT code, replace System.h

Put error code in RegisterContext and replaced idt_flush with inline assembly.
System.h was removed and its contents were put in CPU.h (RegisterContext) and IOPorts.h (outportb, etc.)

Kernel/Modules/Intel8254x/Main.cpp

@@ -4,12 +4,12 @@
 
 #include <APIC.h>
 #include <IDT.h>
+#include <IOPorts.h>
 #include <Logging.h>
 #include <Net/Net.h>
 #include <PCI.h>
 #include <Paging.h>
 #include <PhysicalAllocator.h>
-#include <System.h>
 #include <Timer.h>
 #include <Vector.h>
 

Kernel/include/Arch/x86_64/CPU.h

@@ -1,7 +1,6 @@
 #pragma once
 
 #include <Compiler.h>
-#include <System.h>
 #include <TSS.h>
 #include <stdint.h>
 
@@ -14,11 +13,17 @@ typedef struct {
     uint64_t base;
 } __attribute__((packed)) gdt_ptr_t;
 
+typedef struct {
+    uint16_t limit;
+    uint64_t base;
+} __attribute__((packed)) idt_ptr_t;
+
 struct CPU {
     CPU* self;
     uint64_t id; // APIC/CPU id
     void* gdt;   // GDT
     gdt_ptr_t gdtPtr;
+    idt_ptr_t idtPtr;
     Thread* currentThread = nullptr;
     Thread* idleThread = nullptr;
     Process* idleProcess;
@@ -95,6 +100,52 @@ typedef struct {
     uint32_t features_edx; // CPU features (edx)
 } __attribute__((packed)) cpuid_info_t;
 
+struct RegisterContext {
+    uint64_t r15;
+    uint64_t r14;
+    uint64_t r13;
+    uint64_t r12;
+    uint64_t r11;
+    uint64_t r10;
+    uint64_t r9;
+    uint64_t r8;
+    uint64_t rbp;
+    uint64_t rdi;
+    uint64_t rsi;
+    uint64_t rdx;
+    uint64_t rcx;
+    uint64_t rbx;
+    uint64_t rax;
+    uint64_t err;
+    uint64_t rip;
+    uint64_t cs;
+    uint64_t rflags;
+    uint64_t rsp;
+    uint64_t ss;
+};
+
+typedef struct {
+    uint16_t fcw; // FPU Control Word
+    uint16_t fsw; // FPU Status Word
+    uint8_t ftw;  // FPU Tag Words
+    uint8_t zero; // Literally just contains a zero
+    uint16_t fop; // FPU Opcode
+    uint64_t rip;
+    uint64_t rdp;
+    uint32_t mxcsr;      // SSE Control Register
+    uint32_t mxcsrMask;  // SSE Control Register Mask
+    uint8_t st[8][16];   // FPU Registers, Last 6 bytes reserved
+    uint8_t xmm[16][16]; // XMM Registers
+} __attribute__((packed)) fx_state_t;
+
+static inline int CheckInterrupts() {
+    unsigned long flags;
+    asm volatile("pushf;"
+                 "pop %%rax;"
+                 : "=a"(flags)::"cc");
+    return (flags & 0x200);
+}
+
 cpuid_info_t CPUID();
 
 ALWAYS_INLINE uintptr_t GetRBP() {

Kernel/include/Arch/x86_64/IDT.h

@@ -1,39 +1,32 @@
 #pragma once
 
+#include <CPU.h>
 #include <stdint.h>
-#include <System.h>
 
 #define IRQ0 32
 
 #define IPI_HALT 0xFE
 #define IPI_SCHEDULE 0xFD
 
 typedef struct {
-	uint16_t base_low;
-	uint16_t sel;
-	uint8_t ist;
-	uint8_t flags;
-	uint16_t base_med;
-	uint32_t base_high;
-	uint32_t null;
+    uint16_t base_low;
+    uint16_t sel;
+    uint8_t ist;
+    uint8_t flags;
+    uint16_t base_med;
+    uint32_t base_high;
+    uint32_t null;
 } __attribute__((packed)) idt_entry_t;
 
-typedef struct {
-	uint16_t limit;
-	uint64_t base;
-} __attribute__((packed)) idt_ptr_t;
-
-typedef void(*isr_t)(void*, RegisterContext*);
+typedef void (*isr_t)(void*, RegisterContext*);
 
 extern "C" void idt_flush();
 
-namespace IDT{
-	void Initialize();
-	void RegisterInterruptHandler(uint8_t interrupt, isr_t handler, void* data = nullptr);
-
-	void DisablePIC();
+namespace IDT {
+void Initialize();
+void RegisterInterruptHandler(uint8_t interrupt, isr_t handler, void* data = nullptr);
 
-	uint8_t ReserveUnusedInterrupt();
+void DisablePIC();
 
-	int GetErrCode();
-}
+uint8_t ReserveUnusedInterrupt();
+} // namespace IDT

Kernel/include/Arch/x86_64/IOPorts.h

@@ -0,0 +1,13 @@
+#pragma once
+
+#include <stdint.h>
+
+void outportb(uint16_t port, uint8_t value);
+void outportw(uint16_t port, uint16_t value);
+void outportd(uint16_t port, uint32_t value);
+void outportl(uint16_t port, uint32_t value);
+
+uint8_t inportb(uint16_t port);
+uint16_t inportw(uint16_t port);
+uint32_t inportd(uint16_t port);
+uint32_t inportl(uint16_t port);

Kernel/include/Arch/x86_64/Paging.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <System.h>
+#include <CPU.h>
 #include <stdint.h>
 
 #define KERNEL_VIRTUAL_BASE 0xFFFFFFFF80000000ULL
@@ -82,7 +82,7 @@ typedef struct PageMap { // Each process will have a maximum of 96GB of virtual
 // Allows handling of page faults without kernel panic
 struct PageFaultTrap {
     uintptr_t instructionPointer;
-    void(*handler)();
+    void (*handler)();
 };
 
 class AddressSpace;

Kernel/include/Arch/x86_64/Scheduler.h

@@ -8,14 +8,13 @@
 #include <Lock.h>
 #include <MM/AddressSpace.h>
 #include <Memory.h>
+#include <Objects/Handle.h>
+#include <Objects/Process.h>
 #include <Paging.h>
-#include <System.h>
+#include <Thread.h>
 #include <Timer.h>
 #include <Vector.h>
 #include <stdint.h>
-#include <Objects/Process.h>
-#include <Objects/Handle.h>
-#include <Thread.h>
 
 #define KERNEL_CS 0x08
 #define KERNEL_SS 0x10