turn bkpt! into a function

3 files changed, 44 insertions, 54 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 95f28c7..5289b6f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -37,6 +37,9 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - The safety of assembly wrappers like `wfi` and `interrupt::free` has been
   reviewed. In many cases, the functions are no longer unsafe.
 
+- [breaking-change] `bkpt!` has been turned into a function. It no longer
+  accepts an immediate value.
+
 ### Removed
 
 - `vector_table` and its associated `struct`, `VectorTable`. It's not a good
diff --git a/src/asm.rs b/src/asm.rs
index b94d4ef..c82d45d 100644
--- a/src/asm.rs
+++ b/src/asm.rs
@@ -3,45 +3,30 @@
 /// Puts the processor in Debug state. Debuggers can pick this up as a
 /// "breakpoint".
 ///
-/// Optionally, an "immediate" value (in the 0-255 range) can be passed to
-/// `bkpt!`. The debugger can then read this value using the Program Counter
-/// (PC).
-#[cfg(target_arch = "arm")]
-#[macro_export]
-macro_rules! bkpt {
-    () => {
+/// NOTE calling `bkpt` when the processor is not connected to a debugger will
+/// cause an exception
+#[inline(always)]
+pub fn bkpt() {
+    #[cfg(target_arch = "arm")]
+    unsafe {
         asm!("bkpt"
              :
              :
              :
              : "volatile");
-    };
-    ($imm:expr) => {
-        asm!(concat!("bkpt #", stringify!($imm))
+    }
+}
+
+/// A no-operation. Useful to prevent delay loops from being optimized away.
+pub fn nop() {
+    unsafe {
+        asm!("nop"
              :
              :
              :
              : "volatile");
-    };
-}
-
-/// Puts the processor in Debug state. Debuggers can pick this up as a
-/// "breakpoint".
-///
-/// Optionally, an "immediate" value (in the 0-255 range) can be passed to
-/// `bkpt!`. The debugger can then read this value using the Program Counter
-/// (PC).
-#[cfg(not(target_arch = "arm"))]
-#[macro_export]
-macro_rules! bkpt {
-    () => {
-        asm!("");
-    };
-    ($e:expr) => {
-        asm!("");
-    };
+    }
 }
-
 /// Wait For Event
 pub fn wfe() {
     match () {
@@ -73,14 +58,3 @@ pub fn wfi() {
         () => {}
     }
 }
-
-/// A no-operation. Useful to prevent delay loops from being optimized away.
-pub fn nop() {
-    unsafe {
-        asm!("nop"
-             :
-             :
-             :
-             : "volatile");
-    }
-}
diff --git a/src/exception.rs b/src/exception.rs
index b944d6c..8343d99 100644
--- a/src/exception.rs
+++ b/src/exception.rs
@@ -72,32 +72,48 @@ pub struct Handlers {
     /// Pendable request for system service
     pub pendsv: unsafe extern "C" fn(&PendsvCtxt),
     /// System tick timer
-    pub sys_tick: unsafe extern "C" fn (&SysTickCtxt),
+    pub sys_tick: unsafe extern "C" fn(&SysTickCtxt),
 }
 
 /// Identifies the Nmi exception
-pub struct NmiCtxt { _0: () }
+pub struct NmiCtxt {
+    _0: (),
+}
 
 /// Identifies the HardFault exception
-pub struct HardFaultCtxt { _0: () }
+pub struct HardFaultCtxt {
+    _0: (),
+}
 
 /// Identifies the MemManage exception
-pub struct MemManageCtxt { _0: () }
+pub struct MemManageCtxt {
+    _0: (),
+}
 
 /// Identifies the BusFault exception
-pub struct BusFaultCtxt { _0: () }
+pub struct BusFaultCtxt {
+    _0: (),
+}
 
 /// Identifies the UsageFault exception
-pub struct UsageFaultCtxt { _0: () }
+pub struct UsageFaultCtxt {
+    _0: (),
+}
 
 /// Identifies the Svcall exception
-pub struct SvcallCtxt { _0: () }
+pub struct SvcallCtxt {
+    _0: (),
+}
 
 /// Identifies the Pendsv exception
-pub struct PendsvCtxt { _0: () }
+pub struct PendsvCtxt {
+    _0: (),
+}
 
 /// Identifies the Systick exception
-pub struct SysTickCtxt { _0: () }
+pub struct SysTickCtxt {
+    _0: (),
+}
 
 unsafe impl Token for NmiCtxt {}
 
@@ -134,8 +150,7 @@ pub const DEFAULT_HANDLERS: Handlers = Handlers {
 // This needs asm!, #[naked] and unreachable() to avoid modifying the stack
 // pointer (MSP), that way it points to the stacked registers
 #[naked]
-pub unsafe extern "C" fn default_handler<T>(_token: &T)
-{
+pub unsafe extern "C" fn default_handler<T>(_token: &T) {
     // This is the actual exception handler. `_sf` is a pointer to the previous
     // stack frame
     #[cfg(target_arch = "arm")]
@@ -143,9 +158,7 @@ pub unsafe extern "C" fn default_handler<T>(_token: &T)
         #[cfg(feature = "semihosting")]
         hprintln!("EXCEPTION {:?} @ PC=0x{:08x}", Exception::current(), _sr.pc);
 
-        unsafe {
-            bkpt!();
-        }
+        ::asm::bkpt();
 
         loop {}
     }