docs: improve all new safety comments

Signed-off-by: Florian Hartung <florian.hartung@dlr.de>

Author: florianhartung

src/core/reader/types/mod.rs

@@ -233,7 +233,8 @@ impl BlockType {
                 },
             }),
             BlockType::Type(type_idx) => {
-                // SAFETY: Upheld by the caller
+                // SAFETY: The caller ensures that this `IdxVec` is the same one
+                // used to validate the `TypeIdx` in `self`.
                 let func_type = unsafe { func_types.get(*type_idx) };
                 Ok(func_type.clone())
             }

src/execution/const_interpreter_loop.rs

@@ -57,8 +57,8 @@ pub(crate) fn run_const<T: Config>(
 
                 let module_instance = store.modules.get(module);
 
-                // SAFETY: Validation guarantees the global index to be valid
-                // for the current module.
+                // SAFETY: Validation guarantees the global index to be valid in
+                // the current module.
                 let global_addr = *unsafe { module_instance.global_addrs.get(global_idx) };
 
                 let global = store.globals.get(global_addr);
@@ -100,7 +100,7 @@ pub(crate) fn run_const<T: Config>(
                 // index next.
                 let func_idx = unsafe { FuncIdx::read_unchecked(wasm) };
                 // SAFETY: Validation guarantees the function index to be valid
-                // for the current module.
+                // in the current module.
                 let func_addr = unsafe { store.modules.get(module).func_addrs.get(func_idx) };
                 stack.push_value::<T>(Value::Ref(Ref::Func(*func_addr)))?;
             }