Rename theano.link.c.vm to theano.link.vm

tests/link/test_lazy.py

@@ -124,7 +124,7 @@ def test_ifelse():
 
     for cloop in cloops:
         for lazy in lazys:
-            linker = theano.link.c.vm.VMLinker(use_cloop=cloop, lazy=lazy)
+            linker = theano.link.vm.VMLinker(use_cloop=cloop, lazy=lazy)
             f = function(
                 [a, b, c],
                 ifelse(a, notimpl(b), c),
@@ -154,11 +154,11 @@ def test_nested():
     t4 = ifelseifelseif(tt.eq(x1, x2), x1, tt.eq(x1, 5), x2, c2, t3, t3 + 0.5)
     t4.name = "t4"
 
-    linker = theano.link.c.vm.VMLinker(lazy=False)
+    linker = theano.link.vm.VMLinker(lazy=False)
     f = function([c1, c2, x1, x2], t4, mode=Mode(linker=linker, optimizer="fast_run"))
     with pytest.raises(NotImplementedOpException):
         f(1, 0, np.array(10, dtype=x1.dtype), 0)
 
-    linker = theano.link.c.vm.VMLinker(lazy=True)
+    linker = theano.link.vm.VMLinker(lazy=True)
     f = function([c1, c2, x1, x2], t4, mode=Mode(linker=linker, optimizer="fast_run"))
     assert f(1, 0, np.array(10, dtype=x1.dtype), 0) == 20.5

tests/link/test_vm.py

@@ -6,11 +6,11 @@ import numpy as np
 import pytest
 
 import theano
-from theano import function, tensor
+from theano import config, function, tensor
 from theano.compile import Mode
 from theano.ifelse import ifelse
-from theano.link.c.cc import OpWiseCLinker
-from theano.link.c.vm import VMLinker
+from theano.link.c.exceptions import MissingGXX
+from theano.link.vm import VMLinker
 
 
 class TestCallbacks:
@@ -128,6 +128,8 @@ def test_speed():
 
         print(f"{name} takes {1000 * (t_b - t_a) / (steps_b - steps_a):f} s/Kop")
 
+    from theano.link.c.cc import OpWiseCLinker
+
     time_linker("c|py", OpWiseCLinker)
     time_linker("vmLinker", VMLinker)
     time_linker("vmLinker_nogc", lambda: VMLinker(allow_gc=False))
@@ -443,3 +445,21 @@ def test_no_recycling():
         m1 = f.fn.thunks[0].thunk.module
         m2 = f2.fn.thunks[0].thunk.module
         assert m1 is m2
+
+
+def test_VMLinker_no_cxx():
+    from importlib import reload
+    from unittest.mock import patch
+
+    with config.change_flags(cxx=""):
+        with pytest.raises(MissingGXX):
+            import theano.link.c.cvm
+
+            reload(theano.link.c.cvm)
+
+        with patch.dict("sys.modules", {"theano.link.c.cvm": None}):
+            linker = VMLinker(allow_gc=False, use_cloop=True)
+            a = tensor.scalar()
+
+            with pytest.raises(ModuleNotFoundError):
+                _ = function([a], a, mode=Mode(optimizer=None, linker=linker))

tests/record.py

 from theano.compile import Mode
 from theano.configdefaults import config
 from theano.link.basic import WrapLinkerMany
-from theano.link.c.vm import VMLinker
+from theano.link.vm import VMLinker
 from theano.printing import hex_digest, min_informative_str
 
 

tests/tensor/nnet/test_conv.py

@@ -607,7 +607,7 @@ class TestConv2D(utt.InferShapeTester):
                             openmp=openmp,
                         )
                         mode = theano.Mode(
-                            linker=theano.link.c.vm.VMLinker(
+                            linker=theano.link.vm.VMLinker(
                                 allow_gc=False, use_cloop=True
                             )
                         )

theano/compile/mode.py

@@ -11,8 +11,8 @@ from theano import config, gof
 from theano.compile.function.types import Supervisor
 from theano.link.basic import PerformLinker
 from theano.link.c.cc import CLinker, OpWiseCLinker
-from theano.link.c.vm import VMLinker
 from theano.link.jax import JAXLinker
+from theano.link.vm import VMLinker
 
 
 _logger = logging.getLogger("theano.compile.mode")
@@ -409,7 +409,7 @@ class Mode:
 # string as the key
 # Use VM_linker to allow lazy evaluation by default.
 FAST_COMPILE = Mode(
-    theano.link.c.vm.VMLinker(use_cloop=False, c_thunks=False), "fast_compile"
+    theano.link.vm.VMLinker(use_cloop=False, c_thunks=False), "fast_compile"
 )
 if theano.config.cxx:
     FAST_RUN = Mode("cvm", "fast_run")

theano/compile/nanguardmode.py

@@ -292,7 +292,7 @@ class NanGuardMode(Mode):
             if getattr(var.tag, "nan_guard_mode_check", True):
                 do_check_on(value, None, var=var)
 
-        wrap_linker = theano.link.c.vm.VMLinker(
+        wrap_linker = theano.link.vm.VMLinker(
             callback=nan_check, callback_input=nan_check_input
         )
         super().__init__(wrap_linker, optimizer=self.provided_optimizer)

theano/link/c/cvm.py

+from theano import config
+from theano.link.c.exceptions import MissingGXX
+from theano.link.vm import VM
+
+
+try:
+    # If cxx is explicitly set to an empty string, we do not want to import
+    # either lazy-linker C code or lazy-linker compiled C code from the cache.
+    if not config.cxx:
+        raise MissingGXX(
+            "lazylinker will not be imported if theano.config.cxx is not set."
+        )
+    from theano.link.c import lazylinker_c
+
+    class CVM(lazylinker_c.CLazyLinker, VM):
+        def __init__(self, fgraph, *args, **kwargs):
+            self.fgraph = fgraph
+            lazylinker_c.CLazyLinker.__init__(self, *args, **kwargs)
+            # skip VM.__init__
+
+
+except ImportError:
+    pass
+except (OSError, MissingGXX):
+    # OSError happens when g++ is not installed.  In that case, we
+    # already changed the default linker to something else then CVM.
+    # Currently this is the py linker.
+    # Here we assert that the default linker is not cvm.
+    if config._config_var_dict["linker"].default.startswith("cvm"):
+        raise

theano/link/c/vm.py → theano/link/vm.py

@@ -15,7 +15,6 @@ from collections import defaultdict
 from theano import config
 from theano.gof import Constant, Variable
 from theano.link.basic import Container, LocalLinker
-from theano.link.c.exceptions import MissingGXX
 from theano.link.utils import gc_helper, map_storage, raise_with_op
 
 
@@ -693,32 +692,6 @@ class Stack(VM):
         self.node_cleared_order.append(final_index)
 
 
-try:
-    # If cxx is explicitely set to an empty string, we do not want to import neither lazylinker C code
-    # nor lazylinker compiled C code from cache.
-    if not config.cxx:
-        raise MissingGXX(
-            "lazylinker will not be imported if theano.config.cxx is not set."
-        )
-    from theano.link.c import lazylinker_c
-
-    class CVM(lazylinker_c.CLazyLinker, VM):
-        def __init__(self, fgraph, *args, **kwargs):
-            self.fgraph = fgraph
-            lazylinker_c.CLazyLinker.__init__(self, *args, **kwargs)
-            # skip VM.__init__
-
-
-except ImportError:
-    pass
-except (OSError, MissingGXX) as e:
-    # OSError happens when g++ is not installed.  In that case, we
-    # already changed the default linker to something else then CVM.
-    # Currently this is the py linker.
-    # Here we assert that the default linker is not cvm.
-    assert not config._config_var_dict["linker"].default.startswith("cvm"), e
-
-
 class VMLinker(LocalLinker):
     """
     Class that satisfies the Linker interface by acting as a VM factory.
@@ -948,6 +921,9 @@ class VMLinker(LocalLinker):
                 callback_input=self.callback_input,
             )
         elif self.use_cloop:
+
+            from theano.link.c.cvm import CVM
+
             # create a map from nodes to ints and vars to ints
             nodes_idx = {}
             vars_idx = {}