[interp] Intrinsify span ctor (dotnet#39195)

* [interp] Fix definition of instruction * [interp] Intrinsify span ctor It is heavily used in bcl for static read only spans. In the future we should do copy propagation through its fields so we avoid creating the span in the first place and remove other unecessary opcodes. * [interp] Allow method inlining if constructor is intrinsified * Fix case where has_references is not yet initialized
davmason · Jul 15, 2020 · ef2ecfd · ef2ecfd
1 parent 4cc3750
commit ef2ecfd
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Showing 4 changed files with 50 additions and 6 deletions.
diff --git a/src/mono/mono/metadata/exception.h b/src/mono/mono/metadata/exception.h
@@ -106,8 +106,7 @@ mono_get_exception_argument_null       (const char *arg);
 MONO_API MonoException *
 mono_get_exception_argument            (const char *arg, const char *msg);
 
-MONO_API MONO_RT_EXTERNAL_ONLY
-MonoException *
+MONO_API MonoException *
 mono_get_exception_argument_out_of_range (const char *arg);
 
 MONO_API MONO_RT_EXTERNAL_ONLY

diff --git a/src/mono/mono/mini/interp/interp.c b/src/mono/mono/mini/interp/interp.c
@@ -5269,6 +5269,23 @@ interp_exec_method (InterpFrame *frame, ThreadContext *context, FrameClauseArgs
 			ip++;
 			MINT_IN_BREAK;
 		}
+		MINT_IN_CASE(MINT_INTRINS_SPAN_CTOR) {
+			gpointer ptr = sp [-2].data.p;
+			int len = sp [-1].data.i;
+			if (len < 0)
+				THROW_EX (mono_get_exception_argument_out_of_range ("length"), ip);
+			*(gpointer*)vt_sp = ptr;
+			*(gint32*)((gpointer*)vt_sp + 1) = len;
+			sp [-2].data.p = vt_sp;
+#if SIZEOF_VOID_P == 8
+			vt_sp += ALIGN_TO (12, MINT_VT_ALIGNMENT);
+#else
+			vt_sp += ALIGN_TO (8, MINT_VT_ALIGNMENT);
+#endif
+			sp--;
+			ip++;
+			MINT_IN_BREAK;
+		}
 		MINT_IN_CASE(MINT_INTRINS_BYREFERENCE_GET_VALUE) {
 			gpointer *byreference_this = (gpointer*)sp [-1].data.p;
 			sp [-1].data.p = *byreference_this;

diff --git a/src/mono/mono/mini/interp/mintops.def b/src/mono/mono/mini/interp/mintops.def
@@ -786,7 +786,8 @@ OPDEF(MINT_PROF_COVERAGE_STORE, "prof_coverage_store", 5, Pop0, Push0, MintOpLon
 OPDEF(MINT_INTRINS_ENUM_HASFLAG, "intrins_enum_hasflag", 2, Pop2, Push1, MintOpClassToken)
 OPDEF(MINT_INTRINS_GET_HASHCODE, "intrins_get_hashcode", 1, Pop1, Push1, MintOpNoArgs)
 OPDEF(MINT_INTRINS_GET_TYPE, "intrins_get_type", 1, Pop1, Push1, MintOpNoArgs)
-OPDEF(MINT_INTRINS_BYREFERENCE_CTOR, "intrins_byreference_ctor", 1, Pop1, Push1, MintOpClassToken)
+OPDEF(MINT_INTRINS_BYREFERENCE_CTOR, "intrins_byreference_ctor", 1, Pop1, Push1, MintOpNoArgs)
+OPDEF(MINT_INTRINS_SPAN_CTOR, "intrins_span_ctor", 1, Pop2, Push1, MintOpNoArgs)
 OPDEF(MINT_INTRINS_BYREFERENCE_GET_VALUE, "intrins_byreference_get_value", 1, Pop1, Push1, MintOpNoArgs)
 OPDEF(MINT_INTRINS_UNSAFE_ADD_BYTE_OFFSET, "intrins_unsafe_add_byte_offset", 1, Pop2, Push1, MintOpNoArgs)
 OPDEF(MINT_INTRINS_UNSAFE_BYTE_OFFSET, "intrins_unsafe_byte_offset", 1, Pop2, Push1, MintOpNoArgs)

diff --git a/src/mono/mono/mini/interp/transform.c b/src/mono/mono/mini/interp/transform.c
@@ -3062,6 +3062,20 @@ mono_test_interp_method_compute_offsets (TransformData *td, InterpMethod *imetho
 	interp_method_compute_offsets (td, imethod, signature, header, error);
 }
 
+static gboolean
+type_has_references (MonoType *type)
+{
+	if (MONO_TYPE_IS_REFERENCE (type))
+		return TRUE;
+	if (MONO_TYPE_ISSTRUCT (type)) {
+		MonoClass *klass = mono_class_from_mono_type_internal (type);
+		if (!m_class_is_inited (klass))
+			mono_class_init_internal (klass);
+		return m_class_has_references (klass);
+	}
+	return FALSE;
+}
+
 /* Return false is failure to init basic blocks due to being in inline method */
 static gboolean
 init_bb_start (TransformData *td, MonoMethodHeader *header, gboolean inlining)
@@ -4729,6 +4743,7 @@ generate_code (TransformData *td, MonoMethod *method, MonoMethodHeader *header,
 
 				PUSH_TYPE (td, stack_type [mint_type (m_class_get_byval_arg (klass))], klass);
 			} else {
+				gboolean can_inline = TRUE;
 				if (m_class_get_parent (klass) == mono_defaults.array_class) {
 					interp_add_ins (td, MINT_NEWOBJ_ARRAY);
 					td->last_ins->data [0] = get_data_item_index (td, m->klass);
@@ -4743,6 +4758,14 @@ generate_code (TransformData *td, MonoMethod *method, MonoMethodHeader *header,
 					/* public ByReference(ref T value) */
 					g_assert (csignature->hasthis && csignature->param_count == 1);
 					interp_add_ins (td, MINT_INTRINS_BYREFERENCE_CTOR);
+				} else if (m_class_get_image (klass) == mono_defaults.corlib &&
+						(!strcmp (m_class_get_name (m->klass), "Span`1") ||
+						!strcmp (m_class_get_name (m->klass), "ReadOnlySpan`1")) &&
+						csignature->param_count == 2 &&
+						csignature->params [0]->type == MONO_TYPE_PTR &&
+						!type_has_references (mono_method_get_context (m)->class_inst->type_argv [0])) {
+					/* ctor frequently used with ReadOnlySpan over static arrays */
+					interp_add_ins (td, MINT_INTRINS_SPAN_CTOR);
 				} else if (klass != mono_defaults.string_class &&
 						!mono_class_is_marshalbyref (klass) &&
 						!mono_class_has_finalizer (klass) &&
@@ -4800,6 +4823,7 @@ generate_code (TransformData *td, MonoMethod *method, MonoMethodHeader *header,
 					move_stack (td, (td->sp - td->stack) - csignature->param_count, -2);
 					// Set the method to be executed as part of newobj instruction
 					newobj_fast->data [0] = get_data_item_index (td, mono_interp_get_imethod (domain, m, error));
+					can_inline = FALSE;
 				} else {
 					// Runtime (interp_exec_method_full in interp.c) inserts
 					// extra stack to hold this and return value, before call.
@@ -4809,8 +4833,10 @@ generate_code (TransformData *td, MonoMethod *method, MonoMethodHeader *header,
 					td->last_ins->data [0] = get_data_item_index (td, mono_interp_get_imethod (domain, m, error));
 				}
 				goto_if_nok (error, exit);
-				/* The constructor was not inlined, abort inlining of current method */
-				INLINE_FAILURE;
+				if (!can_inline) {
+					/* The constructor was not inlined, abort inlining of current method */
+					INLINE_FAILURE;
+				}
 
 				td->sp -= csignature->param_count;
 				if (mint_type (m_class_get_byval_arg (klass)) == MINT_TYPE_VT) {
@@ -4827,7 +4853,8 @@ generate_code (TransformData *td, MonoMethod *method, MonoMethodHeader *header,
 					}
 				}
 				if ((vt_stack_used != 0 || vt_res_size != 0) &&
-						td->last_ins->opcode != MINT_INTRINS_BYREFERENCE_CTOR) {
+						td->last_ins->opcode != MINT_INTRINS_BYREFERENCE_CTOR &&
+						td->last_ins->opcode != MINT_INTRINS_SPAN_CTOR) {
 					/* FIXME Remove this once vtsp and sp are unified */
 					interp_add_ins (td, MINT_VTRESULT);
 					td->last_ins->data [0] = vt_res_size;