[sil] Fix parsing of mark_must_check.

As a bonus I put in an extra serialization test as well.

Author: gottesmm

lib/SIL/Parser/ParseSIL.cpp

@@ -3431,11 +3431,6 @@ bool SILParser::parseSpecificSILInstruction(SILBuilder &B,
   }
 
   case SILInstructionKind::MarkMustCheckInst: {
-    if (parseTypedValueRef(Val, B))
-      return true;
-    if (parseSILDebugLocation(InstLoc, B))
-      return true;
-
     StringRef AttrName;
     if (!parseSILOptional(AttrName, *this)) {
       auto diag = diag::sil_markmustcheck_requires_attribute;
@@ -3454,6 +3449,12 @@ bool SILParser::parseSpecificSILInstruction(SILBuilder &B,
       P.diagnose(InstLoc.getSourceLoc(), diag, AttrName);
       return true;
     }
+
+    if (parseTypedValueRef(Val, B))
+      return true;
+    if (parseSILDebugLocation(InstLoc, B))
+      return true;
+
     auto *MVI = B.createMarkMustCheckInst(InstLoc, Val, CKind);
     ResultVal = MVI;
     break;

test/SIL/Parser/basic2_moveonly.sil

@@ -0,0 +1,34 @@
+// RUN: %target-sil-opt -enable-experimental-move-only %s | %target-sil-opt -enable-experimental-move-only | %FileCheck %s
+
+// Once move only is no longer behind a feature flag, merge this into basic2.
+
+sil_stage raw
+
+class Klass {}
+@_moveOnly struct MoveOnlyPair {
+  var lhs: Klass
+  var rhs: Klass
+}
+
+// CHECK-LABEL: sil [ossa] @testMarkMustCheckInst : $@convention(thin) (@guaranteed Klass) -> () {
+// CHECK: mark_must_check [no_implicit_copy] %{{[0-9]+}} : $*MoveOnlyPair
+// CHECK: } // end sil function 'testMarkMustCheckInst'
+sil [ossa] @testMarkMustCheckInst : $@convention(thin) (@guaranteed Klass) -> () {
+bb0(%0 : @guaranteed $Klass):
+  %1 = alloc_box ${ var MoveOnlyPair }
+  %2 = project_box %1 : ${ var MoveOnlyPair }, 0
+  %3 = mark_must_check [no_implicit_copy] %2 : $*MoveOnlyPair
+  %3c = begin_access [modify] [static] %3 : $*MoveOnlyPair
+  %3a = struct_element_addr %3c : $*MoveOnlyPair, #MoveOnlyPair.lhs
+  %3b = struct_element_addr %3c : $*MoveOnlyPair, #MoveOnlyPair.rhs
+  %0a = copy_value %0 : $Klass
+  %0b = copy_value %0 : $Klass
+  store %0a to [init] %3a : $*Klass
+  store %0b to [init] %3b : $*Klass
+  end_access %3c : $*MoveOnlyPair
+
+  destroy_value %1 : ${ var MoveOnlyPair }
+
+  %9999 = tuple()
+  return %9999 : $()
+}

test/SIL/Serialization/basic2_moveonly.sil

@@ -0,0 +1,37 @@
+// RUN: %empty-directory(%t)
+// RUN: %target-sil-opt -enable-experimental-move-only %s -emit-sib -o %t/tmp.sib -module-name basic2
+// RUN: %target-sil-opt -enable-experimental-move-only %t/tmp.sib -o %t/tmp.2.sib -module-name basic2
+// RUN: %target-sil-opt -enable-experimental-move-only %t/tmp.2.sib -module-name basic2 -emit-sorted-sil | %FileCheck %s
+
+// Once move only is no longer behind a feature flag, merge this into basic2.
+
+sil_stage raw
+
+class Klass {}
+@_moveOnly struct MoveOnlyPair {
+  var lhs: Klass
+  var rhs: Klass
+}
+
+// CHECK-LABEL: sil [ossa] @testMarkMustCheckInst : $@convention(thin) (@guaranteed Klass) -> () {
+// CHECK: mark_must_check [no_implicit_copy] %{{[0-9]+}} : $*MoveOnlyPair
+// CHECK: } // end sil function 'testMarkMustCheckInst'
+sil [ossa] @testMarkMustCheckInst : $@convention(thin) (@guaranteed Klass) -> () {
+bb0(%0 : @guaranteed $Klass):
+  %1 = alloc_box ${ var MoveOnlyPair }
+  %2 = project_box %1 : ${ var MoveOnlyPair }, 0
+  %3 = mark_must_check [no_implicit_copy] %2 : $*MoveOnlyPair
+  %3c = begin_access [modify] [static] %3 : $*MoveOnlyPair
+  %3a = struct_element_addr %3c : $*MoveOnlyPair, #MoveOnlyPair.lhs
+  %3b = struct_element_addr %3c : $*MoveOnlyPair, #MoveOnlyPair.rhs
+  %0a = copy_value %0 : $Klass
+  %0b = copy_value %0 : $Klass
+  store %0a to [init] %3a : $*Klass
+  store %0b to [init] %3b : $*Klass
+  end_access %3c : $*MoveOnlyPair
+
+  destroy_value %1 : ${ var MoveOnlyPair }
+
+  %9999 = tuple()
+  return %9999 : $()
+}