delegate-address-dependency.c

typedef struct _MonoDelegateCodeCache
{
	gpointer method_ptr;
	gpointer invoke_impl;
} MonoDelegateCodeCache;

typedef struct _MonoDelegate {
	...
	MonoDelegateCodeCache *cache; // initially NULL
	
	MonoDelegateCodeCache _priv_dont_access_cache;  // inline struct
} MonoDelegate;

void
mono_delegate_trampoline (...)
{
	// start writing to del->_priv_dont_access cache
	MonoDelegateCodeCache *cache = &del->_priv_dont_access_cache;
	
	...
	cache->method_ptr = ...
		
	cache->invoke_impl = ...
		
	mono_write_barrier();
	
	// publish by setting del->cache to a non-NULL value
	del->cache = cache;
}

gpointer
get_delegate_invoke_impl (...)
{
	...
	load_indirect(code, cache_reg, del, MONO_STRUCT_OFFSET (MonoDelegate, cache));
	// address dependency between del->cache and del->cache->code_ptr, no read barrier needed
	load_indirect(code, code_reg, cache_reg, MONO_STRUCT_OFFSET (MonoDelegateCodeCache, code_ptr));
	branch_and_link(code, code_reg);
	...
	return code;
}