dialects: (csl) added csl.addressof_fn (#3135)

Functions like `csl.addressof`, but takes a prop `fn_name` instead of an
SSAValue. Result type is a single const pointer to a function (this is a
limitation imposed by the CSL language.

tests/filecheck/backend/csl/print_csl.mlir

@@ -114,6 +114,10 @@
   %ptr_to_arr = "csl.addressof"(%uninit_array) : (memref<10xf32>) -> !csl.ptr<memref<10xf32>, #csl<ptr_kind single>, #csl<ptr_const var>>
   %ptr_to_val = "csl.addressof"(%const27) : (i16) -> !csl.ptr<i16, #csl<ptr_kind single>, #csl<ptr_const const>>
 
+  %ptr_1_fn = "csl.addressof_fn"() <{fn_name = @args_no_return}> : () -> !csl.ptr<(i32, i32) -> (), #csl<ptr_kind single>, #csl<ptr_const const>>
+  %ptr_2_fn = "csl.addressof_fn"() <{fn_name = @no_args_return}> : () -> !csl.ptr<() -> (f32), #csl<ptr_kind single>, #csl<ptr_const const>>
+
+
 
   "csl.export"(%global_ptr) <{
     type = !csl.ptr<f32, #csl<ptr_kind many>, #csl<ptr_const var>>,
@@ -453,6 +457,8 @@ csl.func @builtins() {
 // CHECK-NEXT: const const_ptr : [*]const i32 = &const_array;
 // CHECK-NEXT: var ptr_to_arr : *[10]f32 = &uninit_array;
 // CHECK-NEXT: const ptr_to_val : *const i16 = &const27;
+// CHECK-NEXT: const ptr_1_fn : *const fn(i32, i32) void = &args_no_return;
+// CHECK-NEXT: const ptr_2_fn : *const fn() f32 = &no_args_return;
 // CHECK-NEXT: comptime {
 // CHECK-NEXT:   @export_symbol(global_ptr, "ptr_name");
 // CHECK-NEXT: }

tests/filecheck/dialects/csl/ops.mlir

@@ -82,6 +82,8 @@ csl.func @initialize() {
     %many_arr_ptr = "csl.addressof"(%arr) : (memref<10xf32>) -> !csl.ptr<f32, #csl<ptr_kind many>, #csl<ptr_const const>>
     %single_arr_ptr = "csl.addressof"(%arr) : (memref<10xf32>) -> !csl.ptr<memref<10xf32>, #csl<ptr_kind single>, #csl<ptr_const const>>
 
+    %function_ptr = "csl.addressof_fn"() <{fn_name = @initialize}> : () -> !csl.ptr<() -> (), #csl<ptr_kind single>, #csl<ptr_const const>>
+
     %dsd_1d = "csl.get_mem_dsd"(%arr, %scalar) : (memref<10xf32>, i32) -> !csl<dsd mem1d_dsd>
     %dsd_2d = "csl.get_mem_dsd"(%arr, %scalar, %scalar) <{"strides" = [3, 4], "offsets" = [1, 2]}> : (memref<10xf32>, i32, i32) -> !csl<dsd mem4d_dsd>
     %dsd_3d = "csl.get_mem_dsd"(%arr, %scalar, %scalar, %scalar) : (memref<10xf32>, i32, i32, i32) -> !csl<dsd mem4d_dsd>
@@ -370,6 +372,7 @@ csl.func @builtins() {
 // CHECK-NEXT:       %scalar_ptr = "csl.addressof"(%scalar) : (i32) -> !csl.ptr<i32, #csl<ptr_kind single>, #csl<ptr_const const>>
 // CHECK-NEXT:       %many_arr_ptr = "csl.addressof"(%arr) : (memref<10xf32>) -> !csl.ptr<f32, #csl<ptr_kind many>, #csl<ptr_const const>>
 // CHECK-NEXT:       %single_arr_ptr = "csl.addressof"(%arr) : (memref<10xf32>) -> !csl.ptr<memref<10xf32>, #csl<ptr_kind single>, #csl<ptr_const const>>
+// CHECK-NEXT:       %function_ptr = "csl.addressof_fn"() <{"fn_name" = @initialize}> : () -> !csl.ptr<() -> (), #csl<ptr_kind single>, #csl<ptr_const const>>
 // CHECK-NEXT:       %dsd_1d = "csl.get_mem_dsd"(%arr, %scalar) : (memref<10xf32>, i32) -> !csl<dsd mem1d_dsd>
 // CHECK-NEXT:       %dsd_2d = "csl.get_mem_dsd"(%arr, %scalar, %scalar) <{"strides" = [3 : i64, 4 : i64], "offsets" = [1 : i64, 2 : i64]}> : (memref<10xf32>, i32, i32) -> !csl<dsd mem4d_dsd>
 // CHECK-NEXT:       %dsd_3d = "csl.get_mem_dsd"(%arr, %scalar, %scalar, %scalar) : (memref<10xf32>, i32, i32, i32) -> !csl<dsd mem4d_dsd>
@@ -605,6 +608,7 @@ csl.func @builtins() {
 // CHECK-GENERIC-NEXT:       %scalar_ptr = "csl.addressof"(%scalar) : (i32) -> !csl.ptr<i32, #csl<ptr_kind single>, #csl<ptr_const const>>
 // CHECK-GENERIC-NEXT:       %many_arr_ptr = "csl.addressof"(%arr) : (memref<10xf32>) -> !csl.ptr<f32, #csl<ptr_kind many>, #csl<ptr_const const>>
 // CHECK-GENERIC-NEXT:       %single_arr_ptr = "csl.addressof"(%arr) : (memref<10xf32>) -> !csl.ptr<memref<10xf32>, #csl<ptr_kind single>, #csl<ptr_const const>>
+// CHECK-GENERIC-NEXT:       %function_ptr = "csl.addressof_fn"() <{"fn_name" = @initialize}> : () -> !csl.ptr<() -> (), #csl<ptr_kind single>, #csl<ptr_const const>>
 // CHECK-GENERIC-NEXT:       %dsd_1d = "csl.get_mem_dsd"(%arr, %scalar) : (memref<10xf32>, i32) -> !csl<dsd mem1d_dsd>
 // CHECK-GENERIC-NEXT:       %dsd_2d = "csl.get_mem_dsd"(%arr, %scalar, %scalar) <{"strides" = [3 : i64, 4 : i64], "offsets" = [1 : i64, 2 : i64]}> : (memref<10xf32>, i32, i32) -> !csl<dsd mem4d_dsd>
 // CHECK-GENERIC-NEXT:       %dsd_3d = "csl.get_mem_dsd"(%arr, %scalar, %scalar, %scalar) : (memref<10xf32>, i32, i32, i32) -> !csl<dsd mem4d_dsd>

xdsl/backend/csl/print_csl.py

@@ -544,6 +544,11 @@ def print_block(self, body: Block):
                     ty = cast(csl.PtrType, res.type)
                     use = self._var_use(res, ty.constness.data.value)
                     self.print(f"{use} = &{val_name};")
+
+                case csl.AddressOfFnOp(fn_name=name, res=res):
+                    ty = cast(csl.PtrType, res.type)
+                    use = self._var_use(res, ty.constness.data.value)
+                    self.print(f"{use} = &{name.string_value()};")
                 case csl.SymbolExportOp(value=val, type=ty) as exp:
                     name = exp.get_name()
                     q_name = f'"{name}"'

xdsl/dialects/csl/csl.py

@@ -1529,6 +1529,39 @@ def verify_(self) -> None:
         return super().verify_()
 
 
+@irdl_op_definition
+class AddressOfFnOp(IRDLOperation):
+    """
+    Takes the address of a function from symbol ref.
+
+    Result has to have kind SINGLE and constness CONST
+    """
+
+    name = "csl.addressof_fn"
+    fn_name = prop_def(SymbolRefAttr)
+
+    res = result_def(PtrType)
+
+    def __init__(self, fn_name: str | SymbolRefAttr):
+        if isinstance(fn_name, str):
+            fn_name = SymbolRefAttr(fn_name)
+
+        super().__init__(properties={"fn_name": fn_name})
+
+    def verify_(self) -> None:
+        ty = self.res.type
+        assert isa(ty, PtrType)
+        if not isa(ty.type, FunctionType):
+            raise VerifyException("Pointed to type must be a function type")
+        if ty.kind.data != PtrKind.SINGLE:
+            raise VerifyException("Pointer kind must be 'single'")
+
+        if ty.constness.data != PtrConst.CONST:
+            raise VerifyException("Function pointers must be const")
+
+        return super().verify_()
+
+
 @irdl_op_definition
 class AddressOfOp(IRDLOperation):
     """
@@ -1733,6 +1766,7 @@ def __init__(self, struct_a: Operation, struct_b: Operation):
     [
         Add16Op,
         Add16cOp,
+        AddressOfFnOp,
         AddressOfOp,
         And16Op,
         CallOp,