Fix order of arguments in x86 set intrinsics

src/pystencils/backend/platforms/x86.py

@@ -153,7 +153,7 @@ class X86VectorCpu(GenericVectorCpu):
         )
 
         values = [PsConstantExpr(PsConstant(v, stype)) for v in c.value]
-        return set_func(*values)
+        return set_func(*values[::-1])
 
     def op_intrinsic(
         self, expr: PsExpression, operands: Sequence[PsExpression]
@@ -202,7 +202,7 @@ class X86VectorCpu(GenericVectorCpu):
                 opstr = expr.function.func.function_name
                 if vtype.width > 256:
                     raise MaterializationError("512bit ceil/floor require SVML.")
-                
+
             case MathFunctions.Sqrt if vtype.is_float():
                 opstr = expr.function.name
 

tests/nbackend/test_vectorization.py

@@ -6,6 +6,7 @@ from itertools import chain
 from functools import partial
 from typing import Callable
 
+from pystencils import DEFAULTS
 from pystencils.backend.kernelcreation import (
     KernelCreationContext,
     AstFactory,
@@ -21,7 +22,6 @@ from pystencils.backend.transformations import (
 from pystencils.backend.constants import PsConstant
 from pystencils.codegen.driver import create_cpu_kernel_function
 from pystencils.jit import LegacyCpuJit
-
 from pystencils import Target, fields, Assignment, Field
 from pystencils.field import create_numpy_array_with_layout
 from pystencils.types import PsScalarType, PsIntegerType
@@ -38,7 +38,9 @@ class VectorTestSetup:
 
     @property
     def name(self) -> str:
-        return f"{self.target.name}/{self.numeric_dtype}<{self.lanes}>/{self.index_dtype}"
+        return (
+            f"{self.target.name}/{self.numeric_dtype}<{self.lanes}>/{self.index_dtype}"
+        )
 
 
 def get_setups(target: Target) -> list[VectorTestSetup]:
@@ -71,7 +73,9 @@ def get_setups(target: Target) -> list[VectorTestSetup]:
             ]
 
         case Target.X86_AVX512_FP16:
-            avx512_platform = partial(X86VectorCpu, vector_arch=X86VectorArch.AVX512_FP16)
+            avx512_platform = partial(
+                X86VectorCpu, vector_arch=X86VectorArch.AVX512_FP16
+            )
             return [
                 VectorTestSetup(target, avx512_platform, 8, Fp(16), SInt(32)),
                 VectorTestSetup(target, avx512_platform, 16, Fp(16), SInt(32)),
@@ -187,7 +191,7 @@ def test_update_kernel(vectorization_setup: VectorTestSetup, ghost_layers: int):
 
     resolution = np.finfo(setup.numeric_dtype.numpy_dtype).resolution
     gls = ghost_layers
-    
+
     np.testing.assert_allclose(
         dst_arr[gls:-gls, gls:-gls, :],
         check_arr[gls:-gls, gls:-gls, :],
@@ -242,3 +246,24 @@ def test_only_trailing_iterations(vectorization_setup: VectorTestSetup):
         kernel(f=f_arr)
 
         np.testing.assert_equal(f_arr, 2.0)
+
+
+def test_set(vectorization_setup: VectorTestSetup):
+    setup = vectorization_setup
+    f = fields(f"f(1): {setup.index_dtype}[1D]", layout="fzyx")
+
+    update = [Assignment(f(0), DEFAULTS.spatial_counters[0])]
+
+    kernel = create_vector_kernel(update, f, setup)
+
+    shape = (23, 1)
+    f_arr = create_numpy_array_with_layout(
+        shape, layout=(1, 0), dtype=setup.index_dtype.numpy_dtype
+    )
+
+    f_arr[:] = 42
+
+    kernel(f=f_arr)
+
+    reference = np.array(range(shape[0])).reshape(shape)
+    np.testing.assert_equal(f_arr, reference)