Merge pull request #61883 from meg-gupta/lbisuniq

LoadBorrowImmutabilityVerifier: Mark is_unique as a write

Author: meg-gupta

lib/SIL/Verifier/LoadBorrowImmutabilityChecker.cpp

@@ -98,7 +98,6 @@ bool GatherWritesVisitor::visitUse(Operand *op, AccessUseType useTy) {
   case SILInstructionKind::DeallocBoxInst:
   case SILInstructionKind::WitnessMethodInst:
   case SILInstructionKind::ExistentialMetatypeInst:
-  case SILInstructionKind::IsUniqueInst:
   case SILInstructionKind::HopToExecutorInst:
   case SILInstructionKind::ExtractExecutorInst:
   case SILInstructionKind::ValueMetatypeInst:
@@ -115,6 +114,7 @@ bool GatherWritesVisitor::visitUse(Operand *op, AccessUseType useTy) {
   case SILInstructionKind::MarkFunctionEscapeInst:
   case SILInstructionKind::DeallocRefInst:
   case SILInstructionKind::DeallocPartialRefInst:
+  case SILInstructionKind::IsUniqueInst:
     writeAccumulator.push_back(op);
     return true;
 

test/SIL/OwnershipVerifier/load_borrow_verify_errors.sil

@@ -1,4 +1,5 @@
 // RUN: %target-sil-opt %s -verify-continue-on-failure=true -o /dev/null 2>&1 | %FileCheck %s
+import Builtin
 
 class Klass {}
 
@@ -71,3 +72,31 @@ bb6(%ld : @guaranteed $Klass):
   return %6 : $()
 }
 
+struct ArrayIntBuffer {
+  var storage : Builtin.NativeObject
+}
+
+struct MyArray<T> {
+  var buffer : ArrayIntBuffer
+}
+
+struct MyStruct {
+}
+
+// CHECK: Write:   %4 = is_unique %1 : $*ArrayIntBuffer
+// CHECK: Begin Error in function test_is_unique
+// CHECK: SIL verification failed: Found load borrow that is invalidated by a local write?!: loadBorrowImmutabilityAnalysis.isImmutable(LBI)
+// CHECK: End Error in function test_is_unique
+sil [ossa] @test_is_unique : $@convention(thin) (@in MyArray<MyStruct>) -> () {
+bb0(%0 : $*MyArray<MyStruct>):
+  %1 = struct_element_addr %0 : $*MyArray<MyStruct>, #MyArray.buffer
+  %2 = load_borrow %1 : $*ArrayIntBuffer
+  %3 = struct $MyArray<MyStruct>(%2 : $ArrayIntBuffer)
+  %6 = is_unique %1 : $*ArrayIntBuffer
+  %7 = struct $MyArray<MyStruct>(%2 : $ArrayIntBuffer)
+  end_borrow %2 : $ArrayIntBuffer
+  destroy_addr %0 : $*MyArray<MyStruct>
+  %t = tuple ()
+  return %t : $()
+}
+