sklam · Jun 25, 2021 · May 24, 2021 · May 25, 2021 · May 25, 2021 · May 25, 2021
diff --git a/.flake8 b/.flake8
@@ -186,7 +186,6 @@ exclude =
     numba/tests/test_buffer_protocol.py
     numba/tests/test_casting.py
     numba/tests/test_lists.py
-    numba/tests/test_blackscholes.py
     numba/tests/test_array_analysis.py
     numba/tests/test_serialize.py
     numba/tests/test_iteration.py

diff --git a/numba/core/cpu.py b/numba/core/cpu.py
@@ -296,6 +296,8 @@ def finalize(self, flags, options):
 
         flags.inherit_if_not_set("fastmath")
 
+        flags.inherit_if_not_set("error_model", default="python")
+
         # Add "target_backend" as a option that inherits from the caller
         flags.inherit_if_not_set("target_backend")
 

diff --git a/numba/core/errors.py b/numba/core/errors.py
@@ -651,6 +651,17 @@ def __init__(self, exception):
         self.old_exception = exception
 
 
+class InternalTargetMismatchError(InternalError):
+    """For signalling a target mismatch error occurred internally within the
+    compiler.
+    """
+    def __init__(self, kind, target_hw, hw_clazz):
+        msg = (f"{kind.title()} being resolved on a target from which it does "
+               f"not inherit. Local target is {target_hw}, declared "
+               f"target class is {hw_clazz}.")
+        super().__init__(msg)
+
+
 class RequireLiteralValue(TypingError):
     """
     For signalling that a function's typing requires a constant value for

diff --git a/numba/core/extending.py b/numba/core/extending.py
@@ -203,10 +203,12 @@ def _overload_method_common(typ, attr, **kwargs):
     from numba.core.typing.templates import make_overload_method_template
 
     def decorate(overload_func):
+        copied_kwargs = kwargs.copy() # avoid mutating parent dict
         template = make_overload_method_template(
             typ, attr, overload_func,
-            inline=kwargs.get('inline', 'never'),
-            prefer_literal=kwargs.get('prefer_literal', False)
+            inline=copied_kwargs.pop('inline', 'never'),
+            prefer_literal=copied_kwargs.pop('prefer_literal', False),
+            **copied_kwargs,
         )
         infer_getattr(template)
         overload(overload_func, **kwargs)(overload_func)

diff --git a/numba/core/target_extension.py b/numba/core/target_extension.py
@@ -1,6 +1,7 @@
 from abc import ABC, abstractmethod
 from numba.core.registry import DelayedRegistry, CPUDispatcher
 from numba.core.decorators import jit
+from numba.core.errors import InternalTargetMismatchError
 from threading import local as tls
 
 
@@ -77,6 +78,35 @@ def resolve_dispatcher_from_str(target_str):
     return dispatcher_registry[target_hw]
 
 
+def _get_local_target_checked(tyctx, hwstr, reason):
+    """Returns the local target if it is compatible with the given target
+    name during a type resolution; otherwise, raises an exception.
+
+    Parameters
+    ----------
+    tyctx: typing context
+    hwstr: str
+        target name to check against
+    reason: str
+        Reason for the resolution. Expects a noun.
+    Returns
+    -------
+    target_hw : Target
+
+    Raises
+    ------
+    InternalTargetMismatchError
+    """
+    # Get the class for the target declared by the function
+    hw_clazz = resolve_target_str(hwstr)
+    # get the local target
+    target_hw = get_local_target(tyctx)
+    # make sure the target_hw is in the MRO for hw_clazz else bail
+    if not target_hw.inherits_from(hw_clazz):
+        raise InternalTargetMismatchError(reason, target_hw, hw_clazz)
+    return target_hw
+
+
 class JitDecorator(ABC):
 
     @abstractmethod

diff --git a/numba/core/types/functions.py b/numba/core/types/functions.py
@@ -391,7 +391,10 @@ def copy(self, this):
 
     @property
     def key(self):
-        return self.typing_key, self.this
+        # FIXME: With target-overload, the MethodTemplate can change depending
+        #        on the target.
+        unique_impl = getattr(self.template, "_overload_func", None)
+        return self.typing_key, self.this, unique_impl
 
     def get_impl_key(self, sig):
         """

diff --git a/numba/core/typing/context.py b/numba/core/typing/context.py
@@ -284,7 +284,33 @@ def core(typ):
                 return attrty
 
     def find_matching_getattr_template(self, typ, attr):
-        for template in self._get_attribute_templates(typ):
+        from numba.core.target_extension import (target_registry,
+                                                 get_local_target)
+
+        templates = list(self._get_attribute_templates(typ))
+
+        # get the current target target
+        target_hw = get_local_target(self)
+
+        # fish out templates that are specific to the target if a target is
+        # specified
+        DEFAULT_TARGET = 'generic'
+        usable = []
+        for ix, temp_cls in enumerate(templates):
+            md = getattr(temp_cls, "metadata", {})
+            hw = md.get('target', DEFAULT_TARGET)
+            if hw is not None:
+                hw_clazz = target_registry[hw]
+                if target_hw.inherits_from(hw_clazz):
+                    usable.append((temp_cls, hw_clazz, ix))
+
+        # sort templates based on target specificity
+        def key(x):
+            return target_hw.__mro__.index(x[1])
+
+        order = [x[0] for x in sorted(usable, key=key)]
+
+        for template in order:
             return_type = template.resolve(typ, attr)
             if return_type is not None:
                 return {

diff --git a/numba/core/typing/templates.py b/numba/core/typing/templates.py
@@ -13,7 +13,11 @@
 
 import numba
 from numba.core import types, utils
-from numba.core.errors import TypingError, InternalError
+from numba.core.errors import (
+    TypingError,
+    InternalError,
+    InternalTargetMismatchError,
+)
 from numba.core.cpu_options import InlineOptions
 
 # info store for inliner callback functions e.g. cost model
@@ -887,23 +891,13 @@ def generic(self, args, kws):
         """
         Type the intrinsic by the arguments.
         """
-        from numba.core.target_extension import (get_local_target,
-                                                 resolve_target_str,
+        from numba.core.target_extension import (_get_local_target_checked,
                                                  dispatcher_registry)
         from numba.core.imputils import builtin_registry
 
         cache_key = self.context, args, tuple(kws.items())
         hwstr = self.metadata.get('target', 'generic')
-        # Get the class for the target declared by the function
-        hw_clazz = resolve_target_str(hwstr)
-        # get the local target
-        target_hw = get_local_target(self.context)
-        # make sure the target_hw is in the MRO for hw_clazz else bail
-        if not target_hw.inherits_from(hw_clazz):
-            msg = (f"Intrinsic being resolved on a target from which it does "
-                   f"not inherit. Local target is {target_hw}, declared "
-                   f"target class is {hw_clazz}.")
-            raise InternalError(msg)
+        target_hw = _get_local_target_checked(self.context, hwstr, "intrinsic")
         disp = dispatcher_registry[target_hw]
         tgtctx = disp.targetdescr.target_context
         # This is all workarounds...
@@ -990,28 +984,12 @@ def make_intrinsic_template(handle, defn, name, kwargs):
 
 
 class AttributeTemplate(object):
-    _initialized = False
-
     def __init__(self, context):
-        self._lazy_class_init()
         self.context = context
 
     def resolve(self, value, attr):
         return self._resolve(value, attr)
 
-    @classmethod
-    def _lazy_class_init(cls):
-        if not cls._initialized:
-            cls.do_class_init()
-            cls._initialized = True
-
-    @classmethod
-    def do_class_init(cls):
-        """
-        Class-wide initialization.  Can be overridden by subclasses to
-        register permanent typing or target hooks.
-        """
-
     def _resolve(self, value, attr):
         fn = getattr(self, "resolve_%s" % attr, None)
         if fn is None:
@@ -1038,15 +1016,33 @@ class _OverloadAttributeTemplate(AttributeTemplate):
     def __init__(self, context):
         super(_OverloadAttributeTemplate, self).__init__(context)
         self.context = context
+        self._init_once()
 
-    @classmethod
-    def do_class_init(cls):
-        """
-        Register attribute implementation.
+    def _get_target_registry(self):
+        """Returns the registry for the current target
         """
-        from numba.core.imputils import lower_getattr
+        from numba.core.target_extension import (_get_local_target_checked,
+                                                 dispatcher_registry)
+        hwstr = self.metadata.get('target', 'generic')
+        target_hw = _get_local_target_checked(self.context, hwstr, "attribute")
+        # Get resgistry for the current hardware
+        disp = dispatcher_registry[target_hw]
+        tgtctx = disp.targetdescr.target_context
+        tgtctx.refresh()
+        if builtin_registry in tgtctx._registries:
+            reg = builtin_registry
+        else:
+            # Pick a registry in which to install intrinsics
+            registries = iter(tgtctx._registries)
+            reg = next(registries)
+        return reg
+
+    def _init_once(self):
+        cls = type(self)
         attr = cls._attr
 
+        lower_getattr = self._get_target_registry().lower_getattr
+
         @lower_getattr(cls.key, attr)
         def getattr_impl(context, builder, typ, value):
             typingctx = context.typing_context
@@ -1082,24 +1078,30 @@ class _OverloadMethodTemplate(_OverloadAttributeTemplate):
     """
     is_method = True
 
-    @classmethod
-    def do_class_init(cls):
+    def _init_once(self):
         """
-        Register generic method implementation.
+        Overriding parent definition
         """
-        from numba.core.imputils import lower_builtin
-        attr = cls._attr
+        attr = self._attr
 
-        @lower_builtin((cls.key, attr), cls.key, types.VarArg(types.Any))
-        def method_impl(context, builder, sig, args):
-            typ = sig.args[0]
-            typing_context = context.typing_context
-            fnty = cls._get_function_type(typing_context, typ)
-            sig = cls._get_signature(typing_context, fnty, sig.args, {})
-            call = context.get_function(fnty, sig)
-            # Link dependent library
-            context.add_linking_libs(getattr(call, 'libs', ()))
-            return call(builder, args)
+        try:
+            registry = self._get_target_registry()
+        except InternalTargetMismatchError:
+            # Target mismatch. Do not register attribute lookup here.
+            pass
+        else:
+            lower_builtin = registry.lower
+
+            @lower_builtin((self.key, attr), self.key, types.VarArg(types.Any))
+            def method_impl(context, builder, sig, args):
+                typ = sig.args[0]
+                typing_context = context.typing_context
+                fnty = self._get_function_type(typing_context, typ)
+                sig = self._get_signature(typing_context, fnty, sig.args, {})
+                call = context.get_function(fnty, sig)
+                # Link dependent library
+                context.add_linking_libs(getattr(call, 'libs', ()))
+                return call(builder, args)
 
     def _resolve(self, typ, attr):
         if self._attr != attr:
@@ -1132,7 +1134,8 @@ def generic(_, args, kws):
 
 def make_overload_attribute_template(typ, attr, overload_func, inline,
                                      prefer_literal=False,
-                                     base=_OverloadAttributeTemplate):
+                                     base=_OverloadAttributeTemplate,
+                                     **kwargs):
     """
     Make a template class for attribute *attr* of *typ* overloaded by
     *overload_func*.
@@ -1145,20 +1148,22 @@ def make_overload_attribute_template(typ, attr, overload_func, inline,
                _inline_overloads={},
                _overload_func=staticmethod(overload_func),
                prefer_literal=prefer_literal,
+               metadata=kwargs,
                )
     obj = type(base)(name, (base,), dct)
     return obj
 
 
 def make_overload_method_template(typ, attr, overload_func, inline,
-                                  prefer_literal=False):
+                                  prefer_literal=False, **kwargs):
     """
     Make a template class for method *attr* of *typ* overloaded by
     *overload_func*.
     """
     return make_overload_attribute_template(
         typ, attr, overload_func, inline=inline,
         base=_OverloadMethodTemplate, prefer_literal=prefer_literal,
+        **kwargs,
     )
 
 

diff --git a/numba/np/arrayobj.py b/numba/np/arrayobj.py
@@ -32,6 +32,7 @@
 from numba.cpython import slicing
 from numba.cpython.unsafe.tuple import tuple_setitem, build_full_slice_tuple
 from numba.core.overload_glue import glue_lowering
+from numba.core.extending import overload_classmethod
 
 
 def set_range_metadata(builder, load, lower_bound, upper_bound):
@@ -3475,10 +3476,16 @@ def _empty_nd_impl(context, builder, arrtype, shapes):
              " the maximum possible size.",)
         )
 
-    align = context.get_preferred_array_alignment(arrtype.dtype)
-    meminfo = context.nrt.meminfo_alloc_aligned(builder, size=allocsize,
-                                                align=align)
+    dtype = arrtype.dtype
+    align_val = context.get_preferred_array_alignment(dtype)
+    align = context.get_constant(types.uint32, align_val)
+    args = (context.get_dummy_value(), allocsize, align)
 
+    mip = types.MemInfoPointer(types.voidptr)
+    arytypeclass = types.TypeRef(type(arrtype))
+    argtypes = signature(mip, arytypeclass, types.intp, types.uint32)
+
+    meminfo = context.compile_internal(builder, _call_allocator, argtypes, args)
     data = context.nrt.meminfo_data(builder, meminfo)
 
     intp_t = context.get_value_type(types.intp)
@@ -3495,6 +3502,35 @@ def _empty_nd_impl(context, builder, arrtype, shapes):
     return ary
 
 
+@overload_classmethod(types.Array, "_allocate")
+def _ol_array_allocate(cls, allocsize, align):
+    """Implements a Numba-only default target (cpu) classmethod on the array type.
+    """
+    def impl(cls, allocsize, align):
+        return intrin_alloc(allocsize, align)
+    return impl
+
+
+def _call_allocator(arrtype, size, align):
+    """Trampoline to call the intrinsic used for allocation
+    """
+    return arrtype._allocate(size, align)
+
+
+@intrinsic
+def intrin_alloc(typingctx, allocsize, align):
+    """Intrinsic to call into the allocator for Array
+    """
+    def codegen(context, builder, signature, args):
+        [allocsize, align] = args
+        meminfo = context.nrt.meminfo_alloc_aligned(builder, allocsize, align)
+        return meminfo
+
+    mip = types.MemInfoPointer(types.voidptr)    # return untyped pointer
+    sig = signature(mip, allocsize, align)
+    return sig, codegen
+
+
 def _zero_fill_array(context, builder, ary):
     """
     Zero-fill an array.  The array must be contiguous.