NFC: [OSSACompleteLifetime] Allow forced verifying

Author: nate-chandler

include/swift/SIL/OSSALifetimeCompletion.h

@@ -57,12 +57,20 @@ class OSSALifetimeCompletion {
   /// Extend trivial variables for lifetime diagnostics (only in SILGenCleanup).
   HandleTrivialVariable_t handleTrivialVariable;
 
+  /// Whether verification of the computed liveness should be run even when the
+  /// global setting is off.
+  /// TODO: Remove this option.
+  bool ForceLivenessVerification;
+
 public:
-  OSSALifetimeCompletion(SILFunction *function, const DominanceInfo *domInfo,
-                         DeadEndBlocks &deadEndBlocks,
-                         HandleTrivialVariable_t handleTrivialVariable = IgnoreTrivialVariable)
+  OSSALifetimeCompletion(
+      SILFunction *function, const DominanceInfo *domInfo,
+      DeadEndBlocks &deadEndBlocks,
+      HandleTrivialVariable_t handleTrivialVariable = IgnoreTrivialVariable,
+      bool forceLivenessVerification = false)
       : domInfo(domInfo), deadEndBlocks(deadEndBlocks),
-        completedValues(function), handleTrivialVariable(handleTrivialVariable) {}
+        completedValues(function), handleTrivialVariable(handleTrivialVariable),
+        ForceLivenessVerification(forceLivenessVerification) {}
 
   /// The kind of boundary at which to complete the lifetime.
   ///

lib/SIL/Utils/OSSALifetimeCompletion.cpp

@@ -501,8 +501,9 @@ bool OSSALifetimeCompletion::analyzeAndUpdateLifetime(
   };
   Walker walker(*this, scopedAddress, boundary, liveness);
   AddressUseKind result = walker.walk(scopedAddress.value);
-  if (VerifyLifetimeCompletion && boundary != Boundary::Availability
-      && result != AddressUseKind::NonEscaping) {
+  if ((VerifyLifetimeCompletion || ForceLivenessVerification) &&
+      boundary != Boundary::Availability &&
+      result != AddressUseKind::NonEscaping) {
     llvm::errs() << "Incomplete liveness for:\n" << scopedAddress.value;
     if (auto *escapingUse = walker.getEscapingUse()) {
       llvm::errs() << "  escapes at:\n";

test/SILOptimizer/dead_code_elimination_ossa.sil

@@ -15,12 +15,18 @@ class C {}
 
 sil @getC : $@convention(thin) () -> @owned C
 sil @barrier : $@convention(thin) () -> ()
+sil @initC : $@convention(thin) (Builtin.Word) -> (@owned C, Builtin.RawPointer)
+sil [readnone] @finalC : $@convention(thin) (@owned C) -> @owned C
 
 struct CAndBit {
     var c: C
     var bit: Int1
 }
 
+struct Bool {
+  var _value: Builtin.Int1
+}
+
 struct MO: ~Copyable {
   var x: Int
   deinit
@@ -507,3 +513,28 @@ bb0(%0 : @owned $Outer):
   return %6 : $()
 }
 
+// CHECK-LABEL: sil [ossa] @dont_remove_lifetime_end_of_escaping_value
+// CHECK:         [[FINALIZE:%[^,]+]] = function_ref @finalC
+// CHECK:         apply [[FINALIZE]]
+// CHECK-LABEL: } // end sil function 'dont_remove_lifetime_end_of_escaping_value'
+sil [ossa] @dont_remove_lifetime_end_of_escaping_value : $@convention(thin) (Bool) -> () {
+bb0(%0 : $Bool):
+  %1 = integer_literal $Builtin.Word, 1
+  %2 = function_ref @initC : $@convention(thin) (Builtin.Word) -> (@owned C, Builtin.RawPointer)
+  %3 = apply %2(%1) : $@convention(thin) (Builtin.Word) -> (@owned C, Builtin.RawPointer)
+  (%4, %5) = destructure_tuple %3
+  %6 = mark_dependence %5 on %4
+  %7 = pointer_to_address %6 to [strict] $*Bool
+  store %0 to [trivial] %7
+  br bb1
+
+bb1:
+  %13 = function_ref @finalC : $@convention(thin) (@owned C) -> @owned C
+  %14 = apply %13(%4) : $@convention(thin) (@owned C) -> @owned C
+  destroy_value %14
+  br bb2
+
+bb2:
+  %17 = tuple ()
+  return %17
+}