Optimize keypaths in language 6 mode

In language 6 mode keypath instructions are created as existentials and the optimizer needs to look through the `open_existential_ref` instructions to recognize a keypath.

rdar://150173106

Author: eeckstein

lib/SILOptimizer/Utils/KeyPathProjector.cpp

@@ -674,8 +674,8 @@ class CompleteKeyPathProjector : public KeyPathProjector {
 
 KeyPathInst *
 KeyPathProjector::getLiteralKeyPath(SILValue keyPath) {
-  while (auto *upCast = dyn_cast<UpcastInst>(keyPath)) {
-    keyPath = lookThroughOwnershipInsts(upCast->getOperand());
+  while (isa<UpcastInst>(keyPath) || isa<OpenExistentialRefInst>(keyPath)) {
+    keyPath = lookThroughOwnershipInsts(cast<SingleValueInstruction>(keyPath)->getOperand(0));
   }
 
   return dyn_cast<KeyPathInst>(keyPath);

test/SILOptimizer/capture_propagate_keypath.swift

@@ -60,6 +60,8 @@ func testGenStr(_ mymap: ((GenStr<Int>)->Int) -> ()) {
 
 // CHECK-LABEL: sil {{.*}} @$s4test0A22GenericEscapingClosureAA5GetIDVySayAA3StrVGSiGyF :
 // CHECK-NOT:     keypath
+// CHECK:         = function_ref @[[SPECIALIZED_CLOSURE:.*]] : $@convention(thin) (@in_guaranteed Str) -> @out Int
+// CHECK-NOT:     keypath
 // CHECK-LABEL:  } // end sil function '$s4test0A22GenericEscapingClosureAA5GetIDVySayAA3StrVGSiGyF'
 @inline(never)
 func testGenericEscapingClosure() -> GetID<[Str], Int> {
@@ -85,6 +87,10 @@ public func _opaqueIdentity<T>(_ x: T) -> T {
   return x
 }
 
+// CHECK:       sil shared {{.*}}@[[SPECIALIZED_CLOSURE]] :
+// CHECK-NOT:     keypath
+// CHECK:       } // end sil function '[[SPECIALIZED_CLOSURE]]'
+
 func calltests() {
   // CHECK-OUTPUT-LABEL: testSimple:
   print("testSimple:")

test/SILOptimizer/optimize_keypath.swift

@@ -3,8 +3,16 @@
 // RUN: %FileCheck %s < %t/output.sil
 // RUN: %FileCheck -check-prefix=CHECK-ALL %s < %t/output.sil
 
+// RUN: %target-swift-frontend -primary-file %s -O -sil-verify-all -swift-version 6 -Xllvm -sil-print-types -emit-sil >%t/output6.sil
+// RUN: %FileCheck %s < %t/output6.sil
+// RUN: %FileCheck -check-prefix=CHECK-ALL %s < %t/output6.sil
+
 // RUN: %target-build-swift -O %s -o %t/a.out
-// RUN: %target-run %t/a.out | %FileCheck %s -check-prefix=CHECK-OUTPUT
+// RUN: %target-run %t/a.out | %FileCheck %s -check-prefix=CHECK-OUTPUT -check-prefix=CHECK5-OUTPUT
+
+// RUN: %target-build-swift -swift-version 6 -O %s -o %t/a6.out
+// RUN: %target-run %t/a6.out | %FileCheck %s -check-prefix=CHECK-OUTPUT
+
 // REQUIRES: executable_test,optimized_stdlib
 // REQUIRES: CPU=arm64 || CPU=x86_64
 
@@ -28,7 +36,9 @@ struct GenStruct<T : P> : P {
   }
 }
 
+#if !swift(>=6)
 var numGenClassObjs = 0
+#endif
 
 final class GenClass<T : P> : P {
   var ct: T
@@ -39,11 +49,15 @@ final class GenClass<T : P> : P {
   init(_ ct: T) {
     self.ct = ct
     self.gs = .init(ct)
+#if !swift(>=6)
     numGenClassObjs += 1
+#endif
   }
 
   deinit {
+#if !swift(>=6)
     numGenClassObjs -= 1
+#endif
   }
 
   func modifyIt() {
@@ -63,7 +77,9 @@ final class DerivedClass2 : DerivedClass<Int> {
 
 final class SimpleClass : P {
   var i: Int
+#if !swift(>=6)
   static var numObjs = 0
+#endif
 
   var tuple = (0, 1)
 
@@ -78,11 +94,15 @@ final class SimpleClass : P {
   init(_ i: Int, nested: Int? = nil) {
     self.i = i
     self.opt = nested.map { Nested(i: $0) }
+#if !swift(>=6)
     Self.numObjs += 1
+#endif
   }
 
   deinit {
+#if !swift(>=6)
     Self.numObjs -= 1
+#endif
   }
 
   func modifyIt() {
@@ -422,7 +442,7 @@ func testModifyOptionalForceClass(_ s: inout SimpleClass) {
 //
 //     Check if value is null
 // CHECK: switch_enum [[O:%[0-9]+]]
-// CHECK: {{bb.}}:
+// CHECK: bb{{.*}}:
 //         Unwrap value
 //     CHECK: [[A1:%[0-9]+]] = alloc_stack
 //     CHECK: store [[O]] to [[A1]]
@@ -453,7 +473,7 @@ func testOptionalChain(_ s: SimpleStruct) -> Int? {
 // CHECK: [[E2:%[0-9]+]] = begin_access [read] [dynamic] [no_nested_conflict] [[E1]]
 //     Check if value is null
 // CHECK: switch_enum [[O:%[0-9]+]]
-// CHECK: {{bb.}}:
+// CHECK: bb{{.*}}:
 //         Unwrap value
 //     CHECK: [[A1:%[0-9]+]] = alloc_stack
 //     CHECK: store [[O]] to [[A1]]
@@ -483,15 +503,15 @@ func testOptionalChainClass(_ s: SimpleClass) -> Int? {
 //
 //     Check if value is null
 // CHECK: switch_enum [[O:%[0-9]+]]
-// CHECK: {{bb.}}:
+// CHECK: bb{{.*}}:
 //         Unwrap value
 //     CHECK: [[A1:%[0-9]+]] = alloc_stack
 //     CHECK: store [[O]] to [[A1]]
 //     CHECK: [[U:%[0-9]+]] = unchecked_take_enum_data_addr [[A1]]
 //
 //         Unwrap nested optional
 //     CHECK: switch_enum [[O2:%[0-9]+]]
-//     CHECK: {{bb.}}:
+//     CHECK: bb{{.*}}:
 //         CHECK: [[A2:%[0-9]+]] = alloc_stack
 //         CHECK: store [[O2]] to [[A2]]
 //         CHECK: [[U2:%[0-9]+]] = unchecked_take_enum_data_addr [[A2]]
@@ -705,9 +725,11 @@ func testit() {
 
 testit()
 
-// CHECK-OUTPUT: SimpleClass obj count: 0
+#if !swift(>=6)
+// CHECK5-OUTPUT: SimpleClass obj count: 0
 print("SimpleClass obj count: \(SimpleClass.numObjs)")
-// CHECK-OUTPUT: GenClass obj count: 0
+// CHECK5-OUTPUT: GenClass obj count: 0
 print("GenClass obj count: \(numGenClassObjs)")
+#endif