Simplify ds segment register management

src/boucane.cc

@@ -58,12 +58,14 @@ void configure_tss(){
 
 void task1(){
     while(1){
+        asm("mov $0xABC, %rax");
         asm("mov $1, %rdi;int $0x30");
     }
 }
 
 void task2(){
     while(1){
+        asm("mov $0xAEBC, %rax");
         asm("mov $2, %rdi;int $0x30");
     }
 }

src/core/int.S

@@ -26,6 +26,9 @@
     push %rbp
     push %rsi
     push %rdi
+    mov %ds, %rax
+    push %rax
+    mov 56(%rsp), %rax # Restore %rax
     push %rax
     mov $0x10, %ax
     mov %ax, %ds
@@ -33,6 +36,8 @@
 .endm
 
 .macro RESTORE_REGS
+    pop %rax
+    mov %rax,%ds
     pop %rdi    
     pop %rsi    
     pop %rbp    

src/core/scheduler.cc

@@ -23,32 +23,28 @@ void schedule(){
 
     // Save current task
     PROC *t=&procs[active_process];
-    t->registers.rdi=stack[0];
-    t->registers.rsi=stack[1];
-    t->registers.rbp=stack[2];
-    t->registers.rdx=stack[3];
-    t->registers.rcx=stack[4];
-    t->registers.rbx=stack[5];
-    t->registers.rax=stack[6];
-    t->registers.r15=stack[7];
-    t->registers.r14=stack[8];
-    t->registers.r13=stack[9];
-    t->registers.r12=stack[10];
-    t->registers.r11=stack[11];
-    t->registers.r10=stack[12];
-    t->registers.r9=stack[13];
-    t->registers.r8=stack[14];
-    t->registers.rip=stack[15];
-    t->registers.cs=stack[16];
-    t->registers.eflags=stack[17];
-    t->registers.rsp=stack[18];
-    t->registers.ss=stack[19];
-    if (t->registers.cs!=0x8)
-        t->registers.ds=0x23;
-    else
-        t->registers.ds=0x10;
+    t->registers.ds=stack[0];
+    t->registers.rdi=stack[1];
+    t->registers.rsi=stack[2];
+    t->registers.rbp=stack[3];
+    t->registers.rdx=stack[4];
+    t->registers.rcx=stack[5];
+    t->registers.rbx=stack[6];
+    t->registers.rax=stack[7];
+    t->registers.r15=stack[8];
+    t->registers.r14=stack[9];
+    t->registers.r13=stack[10];
+    t->registers.r12=stack[11];
+    t->registers.r11=stack[12];
+    t->registers.r10=stack[13];
+    t->registers.r9=stack[14];
+    t->registers.r8=stack[15];
+    t->registers.rip=stack[16];
+    t->registers.cs=stack[17];
+    t->registers.eflags=stack[18];
+    t->registers.rsp=stack[19];
+    t->registers.ss=stack[20];
 
-    //printk("Old task %d     cs:%x  rsp:%x   ds:%x\n ",active_process+1, t->registers.cs,t->registers.rsp,t->registers.ds);
     // Goto next task
     active_process++;
     if(active_process>=nproc)