Enable Alias, refactor C API to reflect Op Semantics (apache#41)

* Enable Alias, refactor C API to reflect Op Semantics

* add alias example

Author: tqchen

nnvm/example/src/operator.cc

@@ -127,6 +127,7 @@ NNVM_REGISTER_OP(identity)
 NNVM_REGISTER_OP(add)
 .describe("add two data together")
 .set_num_inputs(2)
+.add_alias("__add_symbol__")
 .attr<FInferShape>("FInferShape", SameShape)
 .attr<FInplaceOption>("FInplaceOption", InplaceIn0Out0)
 .attr<FGradient>(

nnvm/include/dmlc/registry.h

@@ -26,9 +26,19 @@ namespace dmlc {
 template<typename EntryType>
 class Registry {
  public:
-  /*! \return list of functions in the registry */
-  inline static const std::vector<const EntryType*> &List() {
-    return Get()->entry_list_;
+  /*! \return list of entries in the registry(excluding alias) */
+  inline static const std::vector<const EntryType*>& List() {
+    return Get()->const_list_;
+  }
+  /*! \return list all names registered in the registry, including alias */
+  inline static std::vector<std::string> ListAllNames() {
+    const std::map<std::string, EntryType*> &fmap = Get()->fmap_;
+    typename std::map<std::string, EntryType*>::const_iterator p;
+    std::vector<std::string> names;
+    for (p = fmap.begin(); p !=fmap.end(); ++p) {
+      names.push_back(p->first);
+    }
+    return names;
   }
   /*!
    * \brief Find the entry with corresponding name.
@@ -44,6 +54,21 @@ class Registry {
       return NULL;
     }
   }
+  /*!
+   * \brief Add alias to the key_name
+   * \param key_name The original entry key
+   * \param alias The alias key.
+   */
+  inline void AddAlias(const std::string& key_name,
+                       const std::string& alias) {
+    EntryType* e = fmap_.at(key_name);
+    if (fmap_.count(alias)) {
+      CHECK_EQ(e, fmap_.at(alias))
+          << "Entry " << e->name << " already registered under different entry";
+    } else {
+      fmap_[alias] = e;
+    }
+  }
   /*!
    * \brief Internal function to register a name function under name.
    * \param name name of the function
@@ -55,6 +80,7 @@ class Registry {
     EntryType *e = new EntryType();
     e->name = name;
     fmap_[name] = e;
+    const_list_.push_back(e);
     entry_list_.push_back(e);
     return *e;
   }
@@ -79,16 +105,17 @@ class Registry {
 
  private:
   /*! \brief list of entry types */
-  std::vector<const EntryType*> entry_list_;
+  std::vector<EntryType*> entry_list_;
+  /*! \brief list of entry types */
+  std::vector<const EntryType*> const_list_;
   /*! \brief map of name->function */
   std::map<std::string, EntryType*> fmap_;
   /*! \brief constructor */
   Registry() {}
   /*! \brief destructor */
   ~Registry() {
-    for (typename std::map<std::string, EntryType*>::iterator p = fmap_.begin();
-         p != fmap_.end(); ++p) {
-      delete p->second;
+    for (size_t i = 0; i < entry_list_.size(); ++i) {
+      delete entry_list_[i];
     }
   }
 };

nnvm/include/nnvm/c_api.h

@@ -29,7 +29,7 @@
 typedef unsigned int nn_uint;
 
 /*! \brief handle to a function that takes param and creates symbol */
-typedef void *AtomicSymbolCreator;
+typedef void *OpHandle;
 /*! \brief handle to a symbol that can be bind as operator */
 typedef void *SymbolHandle;
 /*! \brief handle to Graph */
@@ -53,17 +53,39 @@ NNVM_DLL void NNAPISetLastError(const char* msg);
 NNVM_DLL const char *NNGetLastError(void);
 
 /*!
- * \brief list all the available AtomicSymbolEntry
+ * \brief list all the available operator names, include entries.
+ * \param out_size the size of returned array
+ * \param out_array the output operator name array.
+ * \return 0 when success, -1 when failure happens
+ */
+NNVM_DLL int NNListAllOpNames(nn_uint *out_size,
+                              const char*** out_array);
+
+/*!
+ * \brief Get operator handle given name.
+ * \param op_name The name of the operator.
+ * \param op_out The returnning op handle.
+ */
+NNVM_DLL int NNGetOpHandle(const char* op_name,
+                           OpHandle* op_out);
+
+/*!
+ * \brief list all the available operators.
+ *  This won't include the alias, use ListAllNames
+ *  instead to get all alias names.
+ *
  * \param out_size the size of returned array
  * \param out_array the output AtomicSymbolCreator array
  * \return 0 when success, -1 when failure happens
  */
-NNVM_DLL int NNSymbolListAtomicSymbolCreators(nn_uint *out_size,
-                                              AtomicSymbolCreator **out_array);
+NNVM_DLL int NNListUniqueOps(nn_uint *out_size,
+                             OpHandle **out_array);
+
 /*!
  * \brief Get the detailed information about atomic symbol.
- * \param creator the AtomicSymbolCreator.
- * \param name The returned name of the creator.
+ * \param op The operator handle.
+ * \param real_name The returned name of the creator.
+ *   This name is not the alias name of the atomic symbol.
  * \param description The returned description of the symbol.
  * \param num_doc_args Number of arguments that contain documents.
  * \param arg_names Name of the arguments of doc args
@@ -72,24 +94,24 @@ NNVM_DLL int NNSymbolListAtomicSymbolCreators(nn_uint *out_size,
  * \param return_type Return type of the function, if any.
  * \return 0 when success, -1 when failure happens
  */
-NNVM_DLL int NNSymbolGetAtomicSymbolInfo(AtomicSymbolCreator creator,
-                                         const char **name,
-                                         const char **description,
-                                         nn_uint *num_doc_args,
-                                         const char ***arg_names,
-                                         const char ***arg_type_infos,
-                                         const char ***arg_descriptions,
-                                         const char **return_type);
+NNVM_DLL int NNGetOpInfo(OpHandle op,
+                         const char **real_name,
+                         const char **description,
+                         nn_uint *num_doc_args,
+                         const char ***arg_names,
+                         const char ***arg_type_infos,
+                         const char ***arg_descriptions,
+                         const char **return_type);
 /*!
  * \brief Create an AtomicSymbol functor.
- * \param creator the AtomicSymbolCreator
+ * \param op The operator handle
  * \param num_param the number of parameters
  * \param keys the keys to the params
  * \param vals the vals of the params
  * \param out pointer to the created symbol handle
  * \return 0 when success, -1 when failure happens
  */
-NNVM_DLL int NNSymbolCreateAtomicSymbol(AtomicSymbolCreator creator,
+NNVM_DLL int NNSymbolCreateAtomicSymbol(OpHandle op,
                                         nn_uint num_param,
                                         const char **keys,
                                         const char **vals,

nnvm/include/nnvm/op.h

@@ -199,6 +199,13 @@ class Op {
    * \return reference to self.
    */
   inline Op& set_attr_parser(std::function<void (NodeAttrs* attrs)> fn);  // NOLINT(*)
+  /*!
+   * \brief Add another alias to this operator.
+   *   The same Op can be queried with Op::Get(alias)
+   * \param alias The alias of the operator.
+   * \return reference to self.
+   */
+  Op& add_alias(const std::string& alias);  // NOLINT(*)
   /*!
    * \brief Register additional attributes to operator.
    * \param attr_name The name of the attribute.

nnvm/python/nnvm/_base.py

@@ -45,7 +45,7 @@ def _load_lib():
 
 # type definitions
 nn_uint = ctypes.c_uint
-SymbolCreatorHandle = ctypes.c_void_p
+OpHandle = ctypes.c_void_p
 SymbolHandle = ctypes.c_void_p
 GraphHandle = ctypes.c_void_p
 

nnvm/python/nnvm/ctypes/README renamed to nnvm/python/nnvm/_ctypes/README

@@ -8,7 +8,7 @@
 import sys
 from .._base import _LIB
 from .._base import c_array, c_str, nn_uint, py_str, string_types
-from .._base import SymbolHandle
+from .._base import SymbolHandle, OpHandle
 from .._base import check_call, ctypes2docstring
 from ..name import NameManager
 from ..attribute import AttrScope
@@ -114,25 +114,25 @@ def _set_symbol_class(cls):
     _symbol_cls = cls
 
 
-def _make_atomic_symbol_function(handle):
+def _make_atomic_symbol_function(handle, name):
     """Create an atomic symbol function by handle and funciton name."""
-    name = ctypes.c_char_p()
+    real_name = ctypes.c_char_p()
     desc = ctypes.c_char_p()
     num_args = nn_uint()
     arg_names = ctypes.POINTER(ctypes.c_char_p)()
     arg_types = ctypes.POINTER(ctypes.c_char_p)()
     arg_descs = ctypes.POINTER(ctypes.c_char_p)()
     ret_type = ctypes.c_char_p()
 
-    check_call(_LIB.NNSymbolGetAtomicSymbolInfo(
-        handle, ctypes.byref(name), ctypes.byref(desc),
+    check_call(_LIB.NNGetOpInfo(
+        handle, ctypes.byref(real_name), ctypes.byref(desc),
         ctypes.byref(num_args),
         ctypes.byref(arg_names),
         ctypes.byref(arg_types),
         ctypes.byref(arg_descs),
         ctypes.byref(ret_type)))
     param_str = ctypes2docstring(num_args, arg_names, arg_types, arg_descs)
-    func_name = py_str(name.value)
+    func_name = name
     desc = py_str(desc.value)
 
     doc_str = ('%s\n\n' +
@@ -199,22 +199,25 @@ def creator(*args, **kwargs):
     return creator
 
 
-def _init_symbol_module():
+def _init_symbol_module(symbol_class, root_namespace):
     """List and add all the atomic symbol functions to current module."""
-    plist = ctypes.POINTER(ctypes.c_void_p)()
+    _set_symbol_class(symbol_class)
+    plist = ctypes.POINTER(ctypes.c_char_p)()
     size = ctypes.c_uint()
 
-    check_call(_LIB.NNSymbolListAtomicSymbolCreators(ctypes.byref(size),
-                                                     ctypes.byref(plist)))
-    module_obj = sys.modules["nnvm.symbol"]
-    module_internal = sys.modules["nnvm._symbol_internal"]
+    check_call(_LIB.NNListAllOpNames(ctypes.byref(size),
+                                     ctypes.byref(plist)))
+    op_names = []
     for i in range(size.value):
-        hdl = SymbolHandle(plist[i])
-        function = _make_atomic_symbol_function(hdl)
+        op_names.append(py_str(plist[i]))
+
+    module_obj = sys.modules["%s.symbol" % root_namespace]
+    module_internal = sys.modules["%s._symbol_internal" % root_namespace]
+    for name in op_names:
+        hdl = OpHandle()
+        check_call(_LIB.NNGetOpHandle(c_str(name), ctypes.byref(hdl)))
+        function = _make_atomic_symbol_function(hdl, name)
         if function.__name__.startswith('_'):
             setattr(module_internal, function.__name__, function)
         else:
             setattr(module_obj, function.__name__, function)
-
-# Initialize the atomic symbol in startups
-_init_symbol_module()

nnvm/python/nnvm/ctypes/__init__.py renamed to nnvm/python/nnvm/_ctypes/__init__.py

@@ -1,5 +1,5 @@
 ctypedef void* SymbolHandle
-ctypedef void* AtomicSymbolCreator
+ctypedef void* OpHandle
 ctypedef unsigned nn_uint
 
 cdef py_str(const char* x):