Add reference types R32 and R64

-Add resumable_trap, safepoint, isnull, and null instructions
-Add Stackmap struct and StackmapSink trait

Co-authored-by: Mir Ahmed <mirahmed753@gmail.com>
Co-authored-by: Dan Gohman <sunfish@mozilla.com>

cranelift/src/bugpoint.rs

@@ -1,6 +1,6 @@
 //! CLI tool to reduce Cranelift IR files crashing during compilation.
 
-use crate::disasm::{PrintRelocs, PrintTraps};
+use crate::disasm::{PrintRelocs, PrintStackmaps, PrintTraps};
 use crate::utils::{parse_sets_and_triple, read_to_string};
 use cranelift_codegen::ir::{
     Ebb, FuncRef, Function, GlobalValueData, Inst, InstBuilder, InstructionData, StackSlots,
@@ -730,11 +730,16 @@ impl<'a> CrashCheckContext<'a> {
         let res = match std::panic::catch_unwind(std::panic::AssertUnwindSafe(|| {
             let mut relocs = PrintRelocs::new(false);
             let mut traps = PrintTraps::new(false);
+            let mut stackmaps = PrintStackmaps::new(false);
             let mut mem = vec![];
 
-            let _ = self
-                .context
-                .compile_and_emit(self.isa, &mut mem, &mut relocs, &mut traps);
+            let _ = self.context.compile_and_emit(
+                self.isa,
+                &mut mem,
+                &mut relocs,
+                &mut traps,
+                &mut stackmaps,
+            );
         })) {
             Ok(()) => CheckResult::Succeed,
             Err(err) => CheckResult::Crash(get_panic_string(err)),