[move-only] When assigning a var that escapes into a closure into another local, emit the correct error message.

With some of the changes that I have made, we began to emit a mark_must_check
[no_copy] on a copy_addr here. This change teaches the move address checker how
to recognize that in this case if we have a project_box it is actually b/c we
have something captured by an escaping closure.

Author: gottesmm

lib/SILOptimizer/Mandatory/MoveOnlyAddressCheckerUtils.cpp

@@ -1526,6 +1526,13 @@ bool GatherUsesVisitor::visitUse(Operand *op) {
 
     if (markedValue->getCheckKind() ==
         MarkMustCheckInst::CheckKind::NoConsumeOrAssign) {
+      if (isa<ProjectBoxInst>(stripAccessMarkers(markedValue->getOperand()))) {
+        LLVM_DEBUG(llvm::dbgs()
+                   << "Found mark must check [nocopy] use of escaping box: " << *user);
+        diagnosticEmitter.emitAddressEscapingClosureCaptureLoadedAndConsumed(markedValue);
+        emittedEarlyDiagnostic = true;
+        return true;
+      }
       LLVM_DEBUG(llvm::dbgs()
                  << "Found mark must check [nocopy] error: " << *user);
       diagnosticEmitter.emitAddressDiagnosticNoCopy(markedValue, copyAddr);

test/SILOptimizer/moveonly_addresschecker_diagnostics.swift

@@ -3109,9 +3109,9 @@ public func closureCaptureClassUseAfterConsumeError() {
         consumeVal(x2) // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable mutable capture of an escaping closure. One can only read from it or assign over it}}
     }
     f()
-    // TODO: This is wrong
-    let x3 = x2 // expected-note {{consuming use here}}
-    // expected-error @-1 {{'x2' has guaranteed ownership but was consumed}}
+    consumeVal(x2) // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable mutable capture of an escaping closure. One can only read from it or assign over it}}
+    let x3 = x2 // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable mutable capture of an escaping closure. One can only read from it or assign over it}}
+    x2 = Klass()
     let _ = x3
 }
 

test/SILOptimizer/moveonly_objectchecker_diagnostics.swift

@@ -2870,9 +2870,9 @@ public func closureCaptureClassOwnedArgUseAfterConsume4(_ x2: consuming Klass) {
         consumeVal(x2) // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable mutable capture of an escaping closure. One can only read from it or assign over it}}
     }
     f()
-    // TODO: This is wrong
-    let x3 = x2 // expected-note {{consuming use here}}
-    // expected-error @-1 {{'x2' has guaranteed ownership but was consumed}}
+    let x3 = x2 // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable mutable capture of an escaping closure. One can only read from it or assign over it}}
+    consumeVal(x2) // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable mutable capture of an escaping closure. One can only read from it or assign over it}}
+    x2 = Klass()
     let _ = x3
 }
 
@@ -3107,8 +3107,29 @@ public func closureAndClosureCaptureClassUseAfterConsume2(_ x: borrowing Klass)
     }
     f()
     consumeVal(x2) // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable immutable capture of an escaping closure. One can only read from it}}
+    let x3 = x2 // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable immutable capture of an escaping closure. One can only read from it}}
+    _ = x3
 }
 
+public func closureAndClosureCaptureClassUseAfterConsume3(_ x: borrowing Klass) { // expected-error {{'x' has guaranteed ownership but was consumed}}
+    var x2 = x
+    // expected-note @-1 {{consuming use here}}
+    x2 = x
+    // expected-note @-1 {{consuming use here}}
+
+    let f = {
+        let g = {
+            borrowVal(x2)
+            consumeVal(x2) // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable mutable capture of an escaping closure. One can only read from it or assign over it}}
+            consumeVal(x2) // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable mutable capture of an escaping closure. One can only read from it or assign over it}}
+        }
+        g()
+    }
+    f()
+    consumeVal(x2) // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable mutable capture of an escaping closure. One can only read from it or assign over it}}
+    let x3 = x2 // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable mutable capture of an escaping closure. One can only read from it or assign over it}}
+    _ = x3
+}
 
 public func closureAndClosureCaptureClassArgUseAfterConsume(_ x2: borrowing Klass) {
     // expected-error @-1 {{'x2' consumed in closure. This is illegal since if the closure is invoked more than once the binding will be uninitialized on later invocations}}

test/SILOptimizer/moveonly_trivial_addresschecker_diagnostics.swift

@@ -1218,9 +1218,11 @@ public func closureCaptureClassUseAfterConsumeError() {
         consumeVal(x2) // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable mutable capture of an escaping closure. One can only read from it or assign over it}}
     }
     f()
-    // TODO: MG This is wrong
-    let x3 = x2 // expected-note {{consuming use here}}
-    // expected-error @-1 {{'x2' has guaranteed ownership but was consumed}}
+    let x3 = x2 // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable mutable capture of an escaping closure. One can only read from it or assign over it}}
+    consumeVal(x2) // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable mutable capture of an escaping closure. One can only read from it or assign over it}}
+    var x4 = x2 // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable mutable capture of an escaping closure. One can only read from it or assign over it}}
+    x4 = x2 // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable mutable capture of an escaping closure. One can only read from it or assign over it}}
+    _ = x4
     let _ = x3
 }
 

test/SILOptimizer/moveonly_trivial_objectchecker_diagnostics.swift

@@ -1829,9 +1829,8 @@ public func closureCaptureClassOwnedArgUseAfterConsume4(_ x2: consuming NonTrivi
         consumeVal(x2) // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable mutable capture of an escaping closure. One can only read from it or assign over it}} 
     }
     f()
-    // TODO (MG): This is wrong
-    let x3 = x2 // expected-note {{consuming use here}}
-    // expected-error @-1 {{'x2' has guaranteed ownership but was consumed}}
+    let x3 = x2 // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable mutable capture of an escaping closure. One can only read from it or assign over it}}
+    consumeVal(x2) // expected-error {{'x2' was consumed but it is illegal to consume a noncopyable mutable capture of an escaping closure. One can only read from it or assign over it}}
     let _ = x3
 }