Add printing support for Dim3s. (#14)

---------

Co-authored-by: Graham Markall <[email protected]>

Author: brycelelbach

numba_cuda/numba/cuda/printimpl.py

@@ -4,6 +4,7 @@
 from numba.core.errors import NumbaWarning
 from numba.core.imputils import Registry
 from numba.cuda import nvvmutils
+from numba.cuda.types import Dim3
 from warnings import warn
 
 registry = Registry()
@@ -53,6 +54,15 @@ def const_print_impl(ty, context, builder, sigval):
     return rawfmt, [val]
 
 
+@print_item.register(Dim3)
+def dim3_print_impl(ty, context, builder, val):
+    rawfmt = "(%d, %d, %d)"
+    x = builder.extract_value(val, 0)
+    y = builder.extract_value(val, 1)
+    z = builder.extract_value(val, 2)
+    return rawfmt, [x, y, z]
+
+
 @lower(print, types.VarArg(types.Any))
 def print_varargs(context, builder, sig, args):
     """This function is a generic 'print' wrapper for arbitrary types.

numba_cuda/numba/cuda/tests/cudapy/test_print.py

@@ -1,4 +1,5 @@
 from numba.cuda.testing import CUDATestCase, skip_on_cudasim
+import numpy as np
 import subprocess
 import sys
 import unittest
@@ -43,6 +44,19 @@ def printstring():
 cuda.synchronize()
 """
 
+
+printdim3_usecase = """\
+from numba import cuda
+
+@cuda.jit
+def printdim3():
+    print(cuda.threadIdx)
+
+printdim3[1, (2, 2, 2)]()
+cuda.synchronize()
+"""
+
+
 printempty_usecase = """\
 from numba import cuda
 
@@ -105,6 +119,12 @@ def test_string(self):
         expected = ['%d hop! 999' % i for i in range(3)]
         self.assertEqual(sorted(lines), expected)
 
+    def test_dim3(self):
+        output, _ = self.run_code(printdim3_usecase)
+        lines = [line.strip() for line in output.splitlines(True)]
+        expected = [str(i) for i in np.ndindex(2, 2, 2)]
+        self.assertEqual(sorted(lines), expected)
+
     @skip_on_cudasim('cudasim can print unlimited output')
     def test_too_many_args(self):
         # Tests that we emit the format string and warn when there are more