Only save ip and 'archdep' regs when signalling.

src/arch/aarch64/interrupt/handler.rs

@@ -123,8 +123,8 @@ impl InterruptStack {
     pub fn set_stack_pointer(&mut self, sp: usize) {
         self.iret.sp_el0 = sp;
     }
-    pub fn stack_pointer(&self) -> usize {
-        self.iret.sp_el0
+    pub fn sig_archdep_reg(&self) -> usize {
+        self.scratch.x0
     }
     pub fn set_instr_pointer(&mut self, ip: usize) {
         self.iret.elr_el1 = ip;
@@ -132,9 +132,6 @@ impl InterruptStack {
     pub fn instr_pointer(&self) -> usize {
         self.iret.elr_el1
     }
-    pub fn flags(&self) -> usize {
-        0 // TODO
-    }
     // TODO: This can maybe be done in userspace?
     pub fn set_syscall_ret_reg(&mut self, ret: usize) {
         self.scratch.x0 = ret;

src/arch/x86/interrupt/handler.rs

@@ -13,12 +13,6 @@ pub struct ScratchRegisters {
 }
 
 impl ScratchRegisters {
-    pub fn a(&self) -> usize {
-        self.eax
-    }
-    pub fn b(&self) -> usize {
-        self.edx
-    }
     pub fn dump(&self) {
         println!("EAX:   {:08x}", { self.eax });
         println!("ECX:   {:08x}", { self.ecx });
@@ -133,13 +127,10 @@ impl InterruptStack {
     pub fn set_stack_pointer(&mut self, esp: usize) {
         self.iret.esp = esp;
     }
-    pub fn stack_pointer(&self) -> usize {
-        self.iret.esp
-    }
     pub fn instr_pointer(&self) -> usize {
         self.iret.eip
     }
-    pub fn flags(&self) -> usize {
+    pub fn sig_archdep_reg(&self) -> usize {
         self.iret.eflags
     }
     pub fn set_instr_pointer(&mut self, eip: usize) {

src/arch/x86_64/interrupt/handler.rs

@@ -107,13 +107,10 @@ impl InterruptStack {
     pub fn set_stack_pointer(&mut self, rsp: usize) {
         self.iret.rsp = rsp;
     }
-    pub fn stack_pointer(&self) -> usize {
-        self.iret.rsp
-    }
     pub fn instr_pointer(&self) -> usize {
         self.iret.rip
     }
-    pub fn flags(&self) -> usize {
+    pub fn sig_archdep_reg(&self) -> usize {
         self.iret.rflags
     }
     pub fn set_instr_pointer(&mut self, rip: usize) {
@@ -199,14 +196,6 @@ impl InterruptStack {
         self.iret.rflags & FLAG_SINGLESTEP == FLAG_SINGLESTEP
     }
 }
-impl ScratchRegisters {
-    pub fn a(&self) -> usize {
-        self.rax
-    }
-    pub fn b(&self) -> usize {
-        self.rdx
-    }
-}
 
 #[macro_export]
 macro_rules! push_scratch {

src/context/signal.rs

@@ -83,10 +83,7 @@ pub fn signal_handler() {
     };
 
     let ip = regs.instr_pointer();
-    let sp = regs.stack_pointer();
-    let fl = regs.flags();
-    let scratch_a = regs.scratch.a();
-    let scratch_b = regs.scratch.b();
+    let archdep_reg = regs.sig_archdep_reg();
 
     regs.set_instr_pointer(sigh_instr_ptr);
 
@@ -94,10 +91,7 @@ pub fn signal_handler() {
         .expect("cannot have been unset while holding the lock");
 
     thread_ctl.saved_ip.set(ip);
-    thread_ctl.saved_sp.set(sp);
-    thread_ctl.saved_flags.set(fl);
-    thread_ctl.saved_scratch_a.set(scratch_a);
-    thread_ctl.saved_scratch_b.set(scratch_b);
+    thread_ctl.saved_archdep_reg.set(archdep_reg);
 
     thread_ctl.control_flags.store((control_flags | SigcontrolFlags::INHIBIT_DELIVERY).bits(), Ordering::Release);
 }