Optimizer: reimplement simplifications for copy_value and destroy_value in swift

So that they can run in the OnoneSimplification pass

Author: eeckstein

SwiftCompilerSources/Sources/Optimizer/InstructionSimplification/CMakeLists.txt

@@ -14,7 +14,9 @@ swift_compiler_sources(Optimizer
   SimplifyCondBranch.swift
   SimplifyCondFail.swift
   SimplifyConvertEscapeToNoEscape.swift
+  SimplifyCopyValue.swift
   SimplifyDebugStep.swift
+  SimplifyDestroyValue.swift
   SimplifyDestructure.swift
   SimplifyGlobalValue.swift
   SimplifyInitEnumDataAddr.swift

SwiftCompilerSources/Sources/Optimizer/InstructionSimplification/SimplifyCopyValue.swift

@@ -0,0 +1,22 @@
+//===--- SimplifyCopyValue.swift ------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2023 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+import SIL
+
+extension CopyValueInst : OnoneSimplifyable, SILCombineSimplifyable {
+  func simplify(_ context: SimplifyContext) {
+    if fromValue.ownership == .none {
+      uses.replaceAll(with: fromValue, context)
+      context.erase(instruction: self)
+    }
+  }
+}

SwiftCompilerSources/Sources/Optimizer/InstructionSimplification/SimplifyDestroyValue.swift

@@ -0,0 +1,21 @@
+//===--- SimplifyDestroyValue.swift ---------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2023 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+import SIL
+
+extension DestroyValueInst : OnoneSimplifyable, SILCombineSimplifyable {
+  func simplify(_ context: SimplifyContext) {
+    if destroyedValue.ownership == .none {
+      context.erase(instruction: self)
+    }
+  }
+}

SwiftCompilerSources/Sources/Optimizer/PassManager/PassRegistration.swift

@@ -97,6 +97,8 @@ private func registerSwiftPasses() {
   registerForSILCombine(RetainValueInst.self,      { run(RetainValueInst.self, $0) })
   registerForSILCombine(ReleaseValueInst.self,     { run(ReleaseValueInst.self, $0) })
   registerForSILCombine(LoadInst.self,             { run(LoadInst.self, $0) })
+  registerForSILCombine(CopyValueInst.self,        { run(CopyValueInst.self, $0) })
+  registerForSILCombine(DestroyValueInst.self,     { run(DestroyValueInst.self, $0) })
 
   // Test passes
   registerPass(functionUsesDumper, { functionUsesDumper.run($0) })

include/swift/SILOptimizer/PassManager/Passes.def

@@ -493,6 +493,8 @@ SWIFT_SILCOMBINE_PASS(StrongReleaseInst)
 SWIFT_SILCOMBINE_PASS(RetainValueInst)
 SWIFT_SILCOMBINE_PASS(ReleaseValueInst)
 SWIFT_SILCOMBINE_PASS(LoadInst)
+SWIFT_SILCOMBINE_PASS(CopyValueInst)
+SWIFT_SILCOMBINE_PASS(DestroyValueInst)
 
 #undef IRGEN_PASS
 #undef SWIFT_MODULE_PASS

lib/SILOptimizer/SILCombiner/SILCombiner.h

@@ -241,8 +241,6 @@ class SILCombiner :
   SILInstruction *optimizeStringObject(BuiltinInst *BI);
   SILInstruction *visitBuiltinInst(BuiltinInst *BI);
   SILInstruction *visitCondFailInst(CondFailInst *CFI);
-  SILInstruction *visitCopyValueInst(CopyValueInst *cvi);
-  SILInstruction *visitDestroyValueInst(DestroyValueInst *dvi);
   SILInstruction *visitRefToRawPointerInst(RefToRawPointerInst *RRPI);
   SILInstruction *visitUpcastInst(UpcastInst *UCI);
 

lib/SILOptimizer/SILCombiner/SILCombinerMiscVisitors.cpp

@@ -865,37 +865,6 @@ SILInstruction *SILCombiner::visitCondFailInst(CondFailInst *CFI) {
   return nullptr;
 }
 
-SILInstruction *SILCombiner::visitCopyValueInst(CopyValueInst *cvi) {
-  assert(cvi->getFunction()->hasOwnership());
-
-  // Sometimes when RAUWing code we get copy_value on .none values (consider
-  // transformations around function types that result in given a copy_value a
-  // thin_to_thick_function argument). In such a case, just RAUW with the
-  // copy_value's operand since it is a no-op.
-  if (cvi->getOperand()->getOwnershipKind() == OwnershipKind::None) {
-    replaceInstUsesWith(*cvi, cvi->getOperand());
-    return eraseInstFromFunction(*cvi);
-  }
-
-  return nullptr;
-}
-
-SILInstruction *SILCombiner::visitDestroyValueInst(DestroyValueInst *dvi) {
-  assert(dvi->getFunction()->hasOwnership());
-
-  // Sometimes when RAUWing code we get destroy_value on .none values. In such a
-  // case, just delete the destroy_value.
-  //
-  // As an example, consider transformations around function types that result
-  // in a thin_to_thick_function being passed to a destroy_value.
-  if (dvi->getOperand()->getOwnershipKind() == OwnershipKind::None) {
-    eraseInstFromFunction(*dvi);
-    return nullptr;
-  }
-
-  return nullptr;
-}
-
 /// Create a value from stores to an address.
 ///
 /// If there are only stores to \p addr, return the stored value. Also, if there

test/SILOptimizer/definite-init-convert-to-escape.swift

@@ -67,7 +67,6 @@ public func returnOptionalEscape() -> (() ->())?
 // CHECK:   [[BLOCK_PROJ:%.*]] = project_block_storage [[BLOCK_SLOT]]
 // CHECK:   store [[MDI]] to [[BLOCK_PROJ]]
 // CHECK:   [[BLOCK:%.*]] = init_block_storage_header [[BLOCK_SLOT]]
-// CHECK:   release_value [[NONE]]
 // CHECK:   [[SOME_2:%.*]] = enum $Optional<{{.*}}>, #Optional.some!enumelt, [[MDI]]
 // CHECK:   [[BLOCK_COPY:%.*]] = copy_block [[BLOCK]]
 // CHECK:   [[BLOCK_SOME:%.*]]  = enum $Optional<{{.*}}>, #Optional.some!enumelt, [[BLOCK_COPY]]

test/SILOptimizer/definite_init_value_types.swift

@@ -1,5 +1,7 @@
 // RUN: %target-swift-frontend -enable-copy-propagation=requested-passes-only -enable-lexical-lifetimes=false -emit-sil %s | %FileCheck %s
 
+// REQUIRES: swift_in_compiler
+
 enum ValueEnum {
   case a(String)
   case b
@@ -57,7 +59,6 @@ enum ValueEnum {
   // CHECK:      bb6:
   // CHECK-NEXT:   [[NEW_STATE:%.*]] = integer_literal $Builtin.Int1, -1
   // CHECK-NEXT:   store [[NEW_STATE]] to [[STATE]]
-  // CHECK-NEXT:   retain_value [[NEW_SELF]]
   // CHECK-NEXT:   store [[NEW_SELF]] to [[SELF_ACCESS]]
   // CHECK-NEXT:   end_access [[SELF_ACCESS]]
   // CHECK-NEXT:   destroy_addr [[SELF_BOX]]

test/SILOptimizer/mandatory_inlining_reasync.swift

@@ -13,8 +13,7 @@ func reasyncFunction(_ value: Optional<Int>, _ fn: () async throws -> Int) reasy
 
 // CHECK-LABEL: sil hidden @$s26mandatory_inlining_reasync20callsReasyncFunctionSiyF : $@convention(thin) () -> Int {
 // CHECK: [[FN:%.*]] = function_ref @$s26mandatory_inlining_reasync20callsReasyncFunctionSiyFSiyXEfU_ : $@convention(thin) () -> Int
-// CHECK-NEXT: [[THICK:%.*]] = thin_to_thick_function [[FN]] : $@convention(thin) () -> Int to $@noescape @callee_guaranteed () -> Int
-// CHECK-NEXT: [[RESULT:%.*]] = apply [[THICK]]() : $@noescape @callee_guaranteed () -> Int
+// CHECK-NEXT: [[RESULT:%.*]] = apply [[FN]]() : $@convention(thin) () -> Int
 // CHECK-NEXT:  return [[RESULT]] : $Int
 func callsReasyncFunction() -> Int {
   return reasyncFunction(nil, { return 321 } )

test/SILOptimizer/simplify_copy_value.sil

@@ -0,0 +1,28 @@
+// RUN: %target-sil-opt -enable-sil-verify-all %s -onone-simplification -simplify-instruction=copy_value | %FileCheck %s
+
+// REQUIRES: swift_in_compiler
+
+sil_stage canonical
+
+import Builtin
+import Swift
+import SwiftShims
+
+sil @cl : $@convention(thin) () -> Int
+
+// CHECK-LABEL: sil [ossa] @remove_copy :
+// CHECK:         [[F:%.*]] = thin_to_thick_function %0 : $@convention(thin) () -> Int to $@callee_guaranteed () -> Int
+// CHECK-NEXT:    destroy_value [[F]]
+// CHECK:       } // end sil function 'remove_copy'
+sil [ossa] @remove_copy : $@convention(thin) () -> () {
+bb0:
+  %0 = function_ref @cl : $@convention(thin) () -> Int
+  %1 = thin_to_thick_function %0 : $@convention(thin) () -> Int to $@callee_guaranteed () -> Int
+  %2 = copy_value %1 : $@callee_guaranteed () -> Int
+  destroy_value %2 : $@callee_guaranteed () -> Int
+  %4 = tuple ()
+  return %4 : $()
+}
+
+
+

test/SILOptimizer/simplify_destroy_value.sil

@@ -0,0 +1,27 @@
+// RUN: %target-sil-opt -enable-sil-verify-all %s -onone-simplification -simplify-instruction=destroy_value | %FileCheck %s
+
+// REQUIRES: swift_in_compiler
+
+sil_stage canonical
+
+import Builtin
+import Swift
+import SwiftShims
+
+sil @cl : $@convention(thin) () -> Int
+
+// CHECK-LABEL: sil [ossa] @remove_copy :
+// CHECK-NOT:     destroy_value
+// CHECK:       } // end sil function 'remove_copy'
+sil [ossa] @remove_copy : $@convention(thin) () -> () {
+bb0:
+  %0 = function_ref @cl : $@convention(thin) () -> Int
+  %1 = thin_to_thick_function %0 : $@convention(thin) () -> Int to $@callee_guaranteed () -> Int
+  destroy_value %1 : $@callee_guaranteed () -> Int
+  %4 = tuple ()
+  return %4 : $()
+}
+
+
+
+