get pc for freebsd (#2270)

* get pc for freebsd

* whitespace :|

* fix; i386 to x86

* remove x86 since uc_mcontext isn't yet in libc

* freebsd build of rust uses libcc/unwind

crates/jit/src/unwind/systemv.rs

@@ -90,7 +90,7 @@ impl UnwindRegistry {
         let mut eh_frame = EhFrame(EndianVec::new(RunTimeEndian::default()));
         table.write_eh_frame(&mut eh_frame).unwrap();
 
-        if cfg!(all(target_os = "linux", target_env = "gnu")) {
+        if cfg!(any(all(target_os = "linux", target_env = "gnu"), target_os = "freebsd")) {
             // libgcc expects a terminating "empty" length, so write a 0 length at the end of the table.
             eh_frame.0.write_u32(0).unwrap();
         }
@@ -101,7 +101,7 @@ impl UnwindRegistry {
     }
 
     unsafe fn register_frames(&mut self) {
-        if cfg!(all(target_os = "linux", target_env = "gnu")) {
+        if cfg!(any(all(target_os = "linux", target_env = "gnu"), target_os = "freebsd")) {
             // On gnu (libgcc), `__register_frame` will walk the FDEs until an entry of length 0
             let ptr = self.frame_table.as_ptr();
             __register_frame(ptr);

crates/runtime/src/traphandlers.rs

@@ -73,7 +73,7 @@ cfg_if::cfg_if! {
 
             // On ARM, handle Unaligned Accesses.
             // On Darwin, guard page accesses are raised as SIGBUS.
-            if cfg!(target_arch = "arm") || cfg!(target_os = "macos") {
+            if cfg!(target_arch = "arm") || cfg!(target_os = "macos") || cfg!(target_os = "freebsd") {
                 register(&mut PREV_SIGBUS, libc::SIGBUS);
             }
         }
@@ -167,6 +167,9 @@ cfg_if::cfg_if! {
                 } else if #[cfg(target_os = "macos")] {
                     let cx = &*(cx as *const libc::ucontext_t);
                     (*cx.uc_mcontext).__ss.__rip as *const u8
+                } else if #[cfg(all(target_os = "freebsd", target_arch = "x86_64"))] {
+                    let cx = &*(cx as *const libc::ucontext_t);
+                    cx.uc_mcontext.mc_rip as *const u8
                 } else {
                     compile_error!("unsupported platform");
                 }