MemoryLifetime: support unchecked_ref_cast_addr and unconditional_checked_cast_addr instructions

Author: eeckstein

lib/SIL/Verifier/MemoryLifetime.cpp

@@ -357,6 +357,8 @@ bool MemoryLocations::analyzeLocationUsesRecursively(SILValue V, unsigned locIdx
       case SILInstructionKind::LoadBorrowInst:
       case SILInstructionKind::DestroyAddrInst:
       case SILInstructionKind::CheckedCastAddrBranchInst:
+      case SILInstructionKind::UncheckedRefCastAddrInst:
+      case SILInstructionKind::UnconditionalCheckedCastAddrInst:
       case SILInstructionKind::PartialApplyInst:
       case SILInstructionKind::ApplyInst:
       case SILInstructionKind::TryApplyInst:
@@ -914,6 +916,14 @@ void MemoryLifetimeVerifier::initDataflowInBlock(SILBasicBlock *block,
       case SILInstructionKind::DeallocStackInst:
         state.killBits(I.getOperand(0), locations);
         break;
+      case SILInstructionKind::UncheckedRefCastAddrInst:
+      case SILInstructionKind::UnconditionalCheckedCastAddrInst: {
+        SILValue src = I.getOperand(CopyLikeInstruction::Src);
+        SILValue dest = I.getOperand(CopyLikeInstruction::Dest);
+        state.killBits(src, locations);
+        state.genBits(dest, locations);
+        break;
+      }
       case SILInstructionKind::PartialApplyInst:
       case SILInstructionKind::ApplyInst:
       case SILInstructionKind::TryApplyInst: {
@@ -1171,6 +1181,17 @@ void MemoryLifetimeVerifier::checkBlock(SILBasicBlock *block, Bits &bits) {
           requireBitsSet(bits, orig, &I);
         break;
       }
+      case SILInstructionKind::UncheckedRefCastAddrInst:
+      case SILInstructionKind::UnconditionalCheckedCastAddrInst: {
+        SILValue src = I.getOperand(CopyLikeInstruction::Src);
+        SILValue dest = I.getOperand(CopyLikeInstruction::Dest);
+        requireBitsSet(bits, src, &I);
+        locations.clearBits(bits, src);
+        requireBitsClear(bits & nonTrivialLocations, dest, &I);
+        locations.setBits(bits, dest);
+        requireNoStoreBorrowLocation(dest, &I);
+        break;
+      }
       case SILInstructionKind::CheckedCastAddrBranchInst: {
         auto *castInst = cast<CheckedCastAddrBranchInst>(&I);
         requireBitsSet(bits, castInst->getSrc(), &I);

lib/SILOptimizer/Transforms/DestroyHoisting.cpp

@@ -353,6 +353,8 @@ void DestroyHoisting::getUsedLocationsOfInst(Bits &bits, SILInstruction *I) {
     case SILInstructionKind::StoreBorrowInst:
     case SILInstructionKind::CopyAddrInst:
     case SILInstructionKind::InjectEnumAddrInst:
+    case SILInstructionKind::UncheckedRefCastAddrInst:
+    case SILInstructionKind::UnconditionalCheckedCastAddrInst:
     case SILInstructionKind::CheckedCastAddrBranchInst:
     case SILInstructionKind::PartialApplyInst:
     case SILInstructionKind::ApplyInst:

test/SIL/memory_lifetime.sil

@@ -541,3 +541,22 @@ bb3:
   return %res : $()
 }
 
+sil [ossa] @test_unconditional_checked_cast : $@convention(thin) <U, V> (@in U) -> () {
+bb0(%0 : $*U):
+  %s = alloc_stack $V
+  unconditional_checked_cast_addr U in %0 : $*U to V in %s : $*V
+  destroy_addr %s : $*V
+  dealloc_stack %s : $*V
+  %5 = tuple ()
+  return %5 : $()
+}
+
+sil [ossa] @test_unchecked_ref_cast : $@convention(thin) <U : AnyObject, V : AnyObject> (@in U) -> () {
+bb0(%0 : $*U):
+  %s = alloc_stack $V
+  unchecked_ref_cast_addr U in %0 : $*U to V in %s : $*V
+  destroy_addr %s : $*V
+  dealloc_stack %s : $*V
+  %5 = tuple ()
+  return %5 : $()
+}

test/SIL/memory_lifetime_failures.sil

@@ -400,3 +400,48 @@ bb3:
   return %res : $()
 }
 
+// CHECK: SIL memory lifetime failure in @test_unconditional_checked_cast_1: memory is initialized, but shouldn't
+sil [ossa] @test_unconditional_checked_cast_1 : $@convention(thin) <U, V> (@in U) -> () {
+bb0(%0 : $*U):
+  %s = alloc_stack $V
+  unconditional_checked_cast_addr U in %0 : $*U to V in %s : $*V
+  dealloc_stack %s : $*V
+  %5 = tuple ()
+  return %5 : $()
+}
+
+// CHECK: SIL memory lifetime failure in @test_unconditional_checked_cast_2: memory is not initialized, but should
+sil [ossa] @test_unconditional_checked_cast_2 : $@convention(thin) <U, V> (@in_guaranteed U) -> () {
+bb0(%0 : $*U):
+  %u = alloc_stack $U
+  %s = alloc_stack $V
+  unconditional_checked_cast_addr U in %u : $*U to V in %s : $*V
+  destroy_addr %s : $*V
+  dealloc_stack %s : $*V
+  dealloc_stack %u : $*U
+  %5 = tuple ()
+  return %5 : $()
+}
+
+// CHECK: SIL memory lifetime failure in @test_unchecked_ref_cast_1: memory is initialized, but shouldn't
+sil [ossa] @test_unchecked_ref_cast_1 : $@convention(thin) <U : AnyObject, V : AnyObject> (@in U) -> () {
+bb0(%0 : $*U):
+  %s = alloc_stack $V
+  unchecked_ref_cast_addr U in %0 : $*U to V in %s : $*V
+  dealloc_stack %s : $*V
+  %5 = tuple ()
+  return %5 : $()
+}
+
+// CHECK: SIL memory lifetime failure in @test_unchecked_ref_cast_2: memory is not initialized, but should
+sil [ossa] @test_unchecked_ref_cast_2 : $@convention(thin) <U : AnyObject, V : AnyObject> (@in_guaranteed U) -> () {
+bb0(%0 : $*U):
+  %u = alloc_stack $U
+  %s = alloc_stack $V
+  unchecked_ref_cast_addr U in %u : $*U to V in %s : $*V
+  destroy_addr %s : $*V
+  dealloc_stack %s : $*V
+  dealloc_stack %u : $*U
+  %5 = tuple ()
+  return %5 : $()
+}