Update to use the new asm! macro

It's much easier to understand and has a simpler syntax. This breaks compatibility with nightlies older than 08/06/2020 (dd/mm/yyyy)

Author: katietheqt-old

src/protected/stage_3/src/lib.rs

@@ -1,5 +1,4 @@
 #![no_std]
-#![feature(llvm_asm)]
 
 use shared::println;
 
@@ -9,5 +8,12 @@ mod panic;
 pub extern "C" fn third_stage() -> ! {
 	println!("[Bootloader] [32] Stage 3");
 
+	unsafe {
+	    let ptr = 0x110000 as *mut u32;
+	    *ptr = 0xdeadbeef;
+    }
+
+    println!("[Bootloader] [32] > 1MB");
+
 	loop {}
 }

src/real/bootsector/src/console.rs

@@ -17,6 +17,9 @@ pub fn print(s: &[u8]) {
 pub fn print_char(c: u8) {
     let ax = u16::from(c) | 0x0e00;
     unsafe {
-        llvm_asm!("int 0x10" :: "{ax}"(ax) :: "intel" );
+        asm!("int 0x10",
+            in("ax") ax,
+            options(nostack)
+        );
     }
 }

src/real/bootsector/src/lib.rs

@@ -1,4 +1,4 @@
-#![feature(llvm_asm, global_asm)]
+#![feature(asm, global_asm)]
 #![no_std]
 #![allow(dead_code)]
 
@@ -34,10 +34,13 @@ extern "C" fn rust_start(disk_number: u16) -> ! {
 
 fn check_int13h_extensions(disk_number: u16) {
     unsafe {
-        llvm_asm!("
-			int 0x13
-    		jc no_int13h_extensions
-        " :: "{ah}"(0x41), "{bx}"(0x55aa), "{dl}"(disk_number) :: "intel", "volatile");
+        asm!("
+            int 0x13
+            jc no_int13h_extensions",
+
+            in("ax") 0x41, in("bx") 0x55aa, in("dx") disk_number,
+            options(nostack)
+        )
     }
 }
 

src/real/stage_2/src/lib.rs

@@ -1,4 +1,4 @@
-#![feature(global_asm, llvm_asm)]
+#![feature(global_asm, asm)]
 #![no_std]
 
 use shared::linker_symbol;
@@ -52,8 +52,11 @@ pub fn second_stage() -> ! {
 
 fn enable_a20() {
     unsafe {
-        llvm_asm!("in al, 0x92
-                   or al, 2
-                   out 0x92, al" ::: "al" : "intel", "volatile");
+        asm!("in {0}, 0x92
+              or {0}, 2
+              out 0x92, {0}",
+            out(reg) _,
+            options(nostack)
+        );
     }
 }

src/shared/src/dap.rs

@@ -31,9 +31,11 @@ impl DiskAddressPacket {
     #[inline(always)]
     pub unsafe fn perform_load(&self, disk_number: u16) {
         let self_addr = self as *const Self as u16;
-        llvm_asm!("
+        asm!("
             int 0x13
-            jc dap_load_failed
-        " :: "{si}"(self_addr), "{ax}"(0x4200), "{dx}"(disk_number) : "bx" : "intel", "volatile");
+            jc dap_load_failed",
+            in("si") self_addr, in("ax") 0x4200, in("dx") disk_number, out("bx") _,
+            options(nostack)
+        );
     }
 }

src/shared/src/lib.rs

@@ -1,6 +1,6 @@
 #![feature(abi_x86_interrupt)]
 #![feature(const_fn)]
-#![feature(llvm_asm, global_asm)]
+#![feature(asm, global_asm)]
 #![no_std]
 
 pub mod console;

src/shared/src/macros.rs

@@ -3,9 +3,10 @@ macro_rules! linker_symbol {
 	($symbol_name:ident) => {unsafe {
 	    let symbol_value: u32;
 
-		llvm_asm!(concat!("lea eax, ", stringify!($symbol_name))
-			: "={eax}"(symbol_value)
-			::: "intel", "volatile");
+		asm!(
+			concat!("lea {}, ", stringify!($symbol_name)),
+			out(reg) symbol_value
+		);
 
 		symbol_value
 	}};

src/shared/src/structures/gdt.rs

@@ -51,7 +51,10 @@ impl GlobalDescriptorTable {
             limit: (self.table.len() * size_of::<u64>() - 1) as u16,
         };
 
-        llvm_asm!("lgdt ($0)" :: "r" (&ptr) : "memory");
+        asm!("lgdt [{}]",
+             in(reg) &ptr,
+             options(nostack)
+        );
     }
 
     #[inline]

src/shared/src/structures/idt.rs

@@ -86,7 +86,10 @@ impl InterruptDescriptorTable {
             limit: (size_of::<Self>() - 1) as u16,
         };
 
-        llvm_asm!("lidt ($0)" :: "r" (&ptr) : "memory");
+        asm!("lidt [{}]",
+             in(reg) &ptr,
+             options(nostack)
+        );
     }
 }
 
@@ -142,7 +145,11 @@ impl<F> Entry<F> {
         self.offset_high = (addr >> 16) as u16;
 
         let segment: u16;
-        unsafe { llvm_asm!("mov %cs, $0" : "=r" (segment) ) };
+
+        unsafe { asm!("mov {:x}, cs",
+                      out(reg) segment,
+                      options(nostack, nomem)
+               ) };
 
         self.gdt_selector = segment;
 

src/shared/src/utils.rs

@@ -1,6 +1,6 @@
 #[inline(always)]
 pub fn hlt() {
     unsafe {
-        llvm_asm!("hlt" :::: "intel","volatile");
+        asm!("hlt");
     }
 }