Reorder switch_to

redox-os · cd9cf2c5839966b0c32e8dbb6d815c556cd7cb09 · jackpot51 committed Feb 15, 2016 · Feb 15, 2016 · cd9cf2c
1 parent 61ff56e
commit cd9cf2c5839966b0c32e8dbb6d815c556cd7cb09
Unified Split

Showing with 30 additions and 32 deletions.

+1 −1 i386-unknown-redox.json

+28 −30 kernel/arch/context.rs

+1 −1 x86_64-unknown-redox.json
@@ -13,7 +13,7 @@
     "relocation-model": "static",
     "code-model": "kernel",
     "disable-redzone": true,
-    "eliminate_frame_pointer": true,
+    "eliminate-frame-pointer": true,
     "exe-suffix": ".bin",
     "has-rpath": false,
     "no-compiler-rt": true,
@@ -668,19 +668,6 @@ impl Context {
     #[cold]
     #[inline(never)]
     pub unsafe fn switch_to(&mut self, next: &mut Context) {
-        asm!("pushfd
-            pop $0"
-            : "=r"(self.flags)
-            :
-            : "memory"
-            : "intel", "volatile");
-
-        asm!(""
-            : "={esp}"(self.sp)
-            :
-            : "memory"
-            : "intel", "volatile");
-
         asm!("fxsave [$0]"
             :
             : "r"(self.fx)
@@ -697,39 +684,38 @@ impl Context {
                 : "intel", "volatile");
         }
 
-        asm!(""
+        asm!("pushfd
+            pop $0"
+            : "=r"(self.flags)
             :
-            : "{esp}"(next.sp)
             : "memory"
             : "intel", "volatile");
 
-
         asm!("push $0
             popfd"
             :
             : "r"(next.flags)
             : "memory"
             : "intel", "volatile");
-    }
 
-    // This function must not push or pop
-    #[cfg(target_arch = "x86_64")]
-    #[cold]
-    #[inline(never)]
-    pub unsafe fn switch_to(&mut self, next: &mut Context) {
-        asm!("pushfq
-            pop $0"
-            : "=r"(self.flags)
+        asm!("mov $0, esp"
+            : "=r"(self.sp)
             :
             : "memory"
             : "intel", "volatile");
 
-        asm!(""
-            : "={rsp}"(self.sp)
+        asm!("mov esp, $0"
             :
+            : "r"(next.sp)
             : "memory"
             : "intel", "volatile");
+    }
 
+    // This function must not push or pop
+    #[cfg(target_arch = "x86_64")]
+    #[cold]
+    #[inline(never)]
+    pub unsafe fn switch_to(&mut self, next: &mut Context) {
         asm!("fxsave [$0]"
             :
             : "r"(self.fx)
@@ -746,19 +732,31 @@ impl Context {
                 : "intel", "volatile");
         }
 
-        asm!(""
+        asm!("pushfq
+            pop $0"
+            : "=r"(self.flags)
             :
-            : "{rsp}"(next.sp)
             : "memory"
             : "intel", "volatile");
 
-
         asm!("push $0
             popfq"
             :
             : "r"(next.flags)
             : "memory"
             : "intel", "volatile");
+
+        asm!("mov $0, rsp"
+            : "=r"(self.sp)
+            :
+            : "memory"
+            : "intel", "volatile");
+
+        asm!("mov rsp, $0"
+            :
+            : "r"(next.sp)
+            : "memory"
+            : "intel", "volatile");
     }
 }
 
@@ -13,7 +13,7 @@
     "relocation-model": "static",
     "code-model": "kernel",
     "disable-redzone": true,
-    "eliminate_frame_pointer": true,
+    "eliminate-frame-pointer": true,
     "exe-suffix": ".bin",
     "has-rpath": false,
     "no-compiler-rt": true,