Function pointer example

Author: Ivan Butygin

sdc/_concurrent_hash.cpp

@@ -91,6 +91,16 @@ void deleteiter_int_hashmap(void* obj)
     delete static_cast<int_hashmap_iters*>(obj);
 }
 
+using funcptr_t = int32_t(*)(int32_t,int32_t,int32_t);
+int32_t test_funcptr(funcptr_t func, int32_t a, int32_t b)
+{
+    int32_t res = 0;
+    for (int i = 0; i < 10; ++i)
+    {
+        res += func(a, b, i);
+    }
+    return res;
+}
 
 PyMODINIT_FUNC PyInit_hconcurrent_hash()
 {
@@ -118,6 +128,8 @@ PyMODINIT_FUNC PyInit_hconcurrent_hash()
     REGISTER(iterkey_int_hashmap)
     REGISTER(iterval_int_hashmap)
     REGISTER(deleteiter_int_hashmap)
+
+    REGISTER(test_funcptr)
 #undef REGISTER
     return m;
 }

sdc/concurrent_hash.py

@@ -28,8 +28,7 @@
 import sdc
 
 from numba import types, typing, generated_jit
-from numba.extending import models, register_model
-from numba.extending import lower_builtin, overload_method, overload, intrinsic
+from numba.extending import lower_builtin, overload_method, overload, intrinsic, register_jitable
 
 from llvmlite import ir as lir
 import llvmlite.binding as ll
@@ -45,6 +44,8 @@
 ll.add_symbol('iterval_int_hashmap', hconcurrent_hash.iterval_int_hashmap)
 ll.add_symbol('deleteiter_int_hashmap', hconcurrent_hash.deleteiter_int_hashmap)
 
+ll.add_symbol('test_funcptr', hconcurrent_hash.test_funcptr)
+
 _create_int_hashmap = types.ExternalFunction("create_int_hashmap",
                                              types.voidptr())
 _delete_int_hashmap = types.ExternalFunction("delete_int_hashmap",
@@ -65,6 +66,9 @@
 _deleteiter_int_hashmap = types.ExternalFunction("deleteiter_int_hashmap",
                                                  types.void(types.voidptr))
 
+_test_funcptr = types.ExternalFunction("test_funcptr",
+                                       types.int32(types.voidptr,types.int32,types.int32))
+
 
 def create_int_hashmap():
     pass
@@ -102,6 +106,10 @@ def deleteiter_int_hashmap():
     pass
 
 
+def test_funcptr():
+    pass
+
+
 @overload(create_int_hashmap)
 def create_int_hashmap_overload():
     return lambda: _create_int_hashmap()
@@ -145,3 +153,18 @@ def iterval_int_hashmap_overload(h):
 @overload(deleteiter_int_hashmap)
 def deleteiter_int_hashmap_overload(h):
     return lambda h: _deleteiter_int_hashmap(h)
+
+
+
+@register_jitable
+def sink(*args):
+    args[0]
+
+@overload(test_funcptr)
+def test_funcptr_overload(a,b,c):
+    def func(a,b,c):
+        res = _test_funcptr(a,b,c)
+        sink(a,b,c)
+        return res
+
+    return func

sdc/tests/test_dataframe.py

@@ -1794,7 +1794,14 @@ def test_impl():
     def test_tbb(self):
         import sdc.concurrent_hash
 
-        def test_impl():
+        @numba.cfunc("int32(int32, int32, int32)")
+        def callback(x, y, z):
+            return x + y + z
+
+        global funcptr
+        funcptr = callback.address
+
+        def test_impl1():
             h = sdc.concurrent_hash.create_int_hashmap()
 
             sdc.concurrent_hash.addelem_int_hashmap(h, 1, 2)
@@ -1814,8 +1821,15 @@ def test_impl():
             sdc.concurrent_hash.deleteiter_int_hashmap(it)
             sdc.concurrent_hash.delete_int_hashmap(h)
 
-        hpat_func = self.jit(test_impl)
-        hpat_func()
+        hpat_func1 = self.jit(test_impl1)
+        hpat_func1()
+
+        def test_impl2():
+            r = sdc.concurrent_hash.test_funcptr(funcptr, 2, 3)
+            print('res', r)
+
+        hpat_func2 = self.jit(test_impl2)
+        hpat_func2()
 
 
 if __name__ == "__main__":