Hot-Reloading Refactor

Signed-off-by: Jason Volk <jason@zemos.net>

src/core/debug.rs

@@ -0,0 +1,78 @@
+#![allow(dead_code)] // this is a developer's toolbox
+
+use std::{panic, panic::PanicInfo};
+
+/// Log event at given level in debug-mode (when debug-assertions are enabled).
+/// In release-mode it becomes DEBUG level, and possibly subject to elision.
+///
+/// Release-mode can be simulated in debug-mode builds by enabling the feature
+/// 'dev_release_log_level'.
+#[macro_export]
+macro_rules! debug_event {
+	( $level:expr, $($x:tt)+ ) => {
+		if cfg!(debug_assertions) && cfg!(not(feature = "dev_release_log_level")) {
+			tracing::event!( $level, $($x)+ );
+		} else {
+			tracing::debug!( $($x)+ );
+		}
+	}
+}
+
+/// Log message at the ERROR level in debug-mode (when debug-assertions are
+/// enabled). In release-mode it becomes DEBUG level, and possibly subject to
+/// elision.
+#[macro_export]
+macro_rules! debug_error {
+	( $($x:tt)+ ) => {
+		$crate::debug_event!(tracing::Level::ERROR, $($x)+ );
+	}
+}
+
+/// Log message at the WARN level in debug-mode (when debug-assertions are
+/// enabled). In release-mode it becomes DEBUG level, and possibly subject to
+/// elision.
+#[macro_export]
+macro_rules! debug_warn {
+	( $($x:tt)+ ) => {
+		$crate::debug_event!(tracing::Level::WARN, $($x)+ );
+	}
+}
+
+/// Log message at the INFO level in debug-mode (when debug-assertions are
+/// enabled). In release-mode it becomes DEBUG level, and possibly subject to
+/// elision.
+#[macro_export]
+macro_rules! debug_info {
+	( $($x:tt)+ ) => {
+		$crate::debug_event!(tracing::Level::INFO, $($x)+ );
+	}
+}
+
+pub fn set_panic_trap() {
+	let next = panic::take_hook();
+	panic::set_hook(Box::new(move |info| {
+		panic_handler(info, &next);
+	}));
+}
+
+#[inline(always)]
+fn panic_handler(info: &PanicInfo<'_>, next: &dyn Fn(&PanicInfo<'_>)) {
+	trap();
+	next(info);
+}
+
+#[inline(always)]
+#[allow(unexpected_cfgs)]
+pub fn trap() {
+	#[cfg(core_intrinsics)]
+	//SAFETY: embeds llvm intrinsic for hardware breakpoint
+	unsafe {
+		std::intrinsics::breakpoint();
+	}
+
+	#[cfg(all(not(core_intrinsics), target_arch = "x86_64"))]
+	//SAFETY: embeds instruction for hardware breakpoint
+	unsafe {
+		std::arch::asm!("int3");
+	}
+}