Bailout SwiftCompilerSource's function signature opts for functions with lifetime dependencies

SwiftCompilerSources/Sources/Optimizer/Utilities/FunctionSignatureTransforms.swift

@@ -12,6 +12,29 @@
 
 import SIL
 
+private extension ArgumentConventions {
+  func isLifetimeSourceOrTarget(index argIndex: Int) -> Bool {
+    // Check if `argIndex` is a lifetime target
+    if self[parameterDependencies: argIndex] != nil {
+      return true
+    }
+
+    // Check if `argIndex` is a lifetime source in resultDependencies
+    if self[resultDependsOn: argIndex] != nil {
+      return true
+    }
+
+    // Check if `argIndex` is a lifetime source in parameterDependencies
+    for targetIndex in firstParameterIndex..<self.count {
+      if getDependence(target: targetIndex, source: argIndex) != nil {
+        return true
+      }
+    }
+
+    return false
+  }
+}
+
 /// Replace an apply with metatype arguments with an apply to a specialized function, where the
 /// metatype values are not passed, but rematerialized in the entry block of the specialized function
 ///
@@ -52,6 +75,15 @@ func specializeByRemovingMetatypeArguments(apply: FullApplySite, _ context: Modu
     return
   }
 
+  // If a function has lifetime dependencies, bailout if dead arguments precede lifetime sources or targets
+  if callee.convention.hasLifetimeDependencies() {
+    for (argIndex, _) in callee.arguments.enumerated() where argIndex >= deadArgIndices.first! {
+      if callee.argumentConventions.isLifetimeSourceOrTarget(index: argIndex) {
+        return
+      }
+    }
+  }
+
   let specializedFuncName = context.mangle(withDeadArguments: deadArgIndices, from: callee)
 
   let specializedCallee: Function

test/SILOptimizer/mandatory_performance_optimizations.sil

@@ -1,6 +1,7 @@
-// RUN: %target-sil-opt -sil-print-types -enable-sil-verify-all %s -mandatory-performance-optimizations | %FileCheck %s
+// RUN: %target-sil-opt -sil-print-types -enable-sil-verify-all %s -mandatory-performance-optimizations -enable-experimental-feature Lifetimes | %FileCheck %s
 
 // REQUIRES: swift_in_compiler
+// REQUIRES: swift_feature_Lifetimes
 
 sil_stage canonical
 
@@ -222,6 +223,78 @@ bb0(%0 : $Int, %1 : $@thick Int.Type, %2 : @owned $Builtin.NativeObject):
   return %2 : $Builtin.NativeObject
 }
 
+sil [no_locks] [perf_constraint] [ossa] @dont_remove_metatype_arg_lifetime : $@convention(thin) (Int, UnsafeRawPointer) -> @lifetime(borrow 1) Span<Int> {
+bb0(%0 : $Int, %1 : $UnsafeRawPointer):
+  %3 = metatype $@thick Int.Type
+  %7 = function_ref @metatype_arg_lifetime : $@convention(thin) (Int, @thick Int.Type, UnsafeRawPointer) -> @lifetime(borrow 2) Span<Int>
+  %8 = apply %7(%0, %3, %1) : $@convention(thin) (Int, @thick Int.Type, UnsafeRawPointer) -> @lifetime(borrow 2) Span<Int>
+  return %8
+}
+
+sil [ossa] @get_span : $@convention(thin) (UnsafeRawPointer) -> @lifetime(borrow 0) Span<Int>
+
+// CHECK-NOT: sil [signature_optimized_thunk] [ossa] @metatype_arg_lifetime :
+sil [ossa] @metatype_arg_lifetime : $@convention(thin) (Int, @thick Int.Type, UnsafeRawPointer) -> @lifetime(borrow 2) Span<Int> {
+bb0(%0 : $Int, %1 : $@thick Int.Type, %2 : $UnsafeRawPointer):
+  fix_lifetime %1 : $@thick Int.Type
+  %3 = function_ref @get_span : $@convention(thin) (UnsafeRawPointer) -> @lifetime(borrow 0) Span<Int>
+  %4 = apply %3(%2) : $@convention(thin) (UnsafeRawPointer) -> @lifetime(borrow 0) Span<Int>
+  return %4
+}
+
+sil [no_locks] [perf_constraint] [ossa] @can_remove_metatype_arg_lifetime : $@convention(thin) (Int, UnsafeRawPointer) -> @lifetime(borrow 1) Span<Int> {
+bb0(%0 : $Int, %1 : $UnsafeRawPointer):
+  %3 = metatype $@thick Int.Type
+  %7 = function_ref @metatype_arg_lifetime_opt : $@convention(thin) (UnsafeRawPointer, Int, @thick Int.Type) -> @lifetime(borrow 0) Span<Int>
+  %8 = apply %7(%1, %0, %3) : $@convention(thin) (UnsafeRawPointer, Int, @thick Int.Type) -> @lifetime(borrow 0) Span<Int>
+  return %8
+}
+
+// CHECK: sil [signature_optimized_thunk] [ossa] @metatype_arg_lifetime_opt :
+sil [ossa] @metatype_arg_lifetime_opt : $@convention(thin) (UnsafeRawPointer, Int, @thick Int.Type) -> @lifetime(borrow 0) Span<Int> {
+bb0(%2 : $UnsafeRawPointer, %0 : $Int, %1 : $@thick Int.Type):
+  fix_lifetime %1 : $@thick Int.Type
+  %3 = function_ref @get_span : $@convention(thin) (UnsafeRawPointer) -> @lifetime(borrow 0) Span<Int>
+  %4 = apply %3(%2) : $@convention(thin) (UnsafeRawPointer) -> @lifetime(borrow 0) Span<Int>
+  return %4
+}
+
+sil [no_locks] [perf_constraint] [ossa] @dont_remove_metatype_arg_lifetime_inout : $@convention(thin) (Int, @lifetime(copy 2) @inout MutableSpan<Int>, @owned MutableSpan<Int>) -> () {
+bb0(%0 : $Int, %1 : $*MutableSpan<Int>, %2 : @owned $MutableSpan<Int>):
+  %3 = metatype $@thick Int.Type
+  %7 = function_ref @metatype_arg_lifetime_inout : $@convention(thin) (Int, @thick Int.Type, @lifetime(copy 3) @inout MutableSpan<Int>, @owned MutableSpan<Int>) -> ()
+  %8 = apply %7(%0, %3, %1, %2) : $@convention(thin) (Int, @thick Int.Type, @lifetime(copy 3) @inout MutableSpan<Int>, @owned MutableSpan<Int>) -> ()
+  %r = tuple ()
+  return %r
+}
+
+// CHECK-NOT: sil [signature_optimized_thunk] [ossa] @metatype_arg_lifetime_inout :
+sil [ossa] @metatype_arg_lifetime_inout : $@convention(thin) (Int, @thick Int.Type, @lifetime(copy 3) @inout MutableSpan<Int>, @owned MutableSpan<Int>) -> () {
+bb0(%0 : $Int, %1 : $@thick Int.Type, %2 : $*MutableSpan<Int>, %3 : @owned $MutableSpan<Int>):
+  fix_lifetime %1 : $@thick Int.Type
+  destroy_value %3
+  %r = tuple ()
+  return %r
+}
+
+sil [no_locks] [perf_constraint] [ossa] @dont_remove_metatype_arg_lifetime_inout_source : $@convention(thin) (Int, @lifetime(copy 2) @inout MutableSpan<Int>, @owned MutableSpan<Int>) -> () {
+bb0(%0 : $Int, %1 : $*MutableSpan<Int>, %2 : @owned $MutableSpan<Int>):
+  %3 = metatype $@thick Int.Type
+  %7 = function_ref @metatype_arg_lifetime_inout_source : $@convention(thin) (@lifetime(copy 3) @inout MutableSpan<Int>, Int, @thick Int.Type, @owned MutableSpan<Int>) -> ()
+  %8 = apply %7(%1, %0, %3, %2) : $@convention(thin) (@lifetime(copy 3) @inout MutableSpan<Int>, Int, @thick Int.Type, @owned MutableSpan<Int>) -> ()
+  %r = tuple ()
+  return %r
+}
+
+// CHECK-NOT: sil [signature_optimized_thunk] [ossa] @metatype_arg_lifetime_inout_source :
+sil [ossa] @metatype_arg_lifetime_inout_source : $@convention(thin) (@lifetime(copy 3) @inout MutableSpan<Int>, Int, @thick Int.Type, @owned MutableSpan<Int>) -> () {
+bb0(%2 : $*MutableSpan<Int>, %0 : $Int, %1 : $@thick Int.Type, %3 : @owned $MutableSpan<Int>):
+  fix_lifetime %1 : $@thick Int.Type
+  destroy_value %3
+  %r = tuple ()
+  return %r
+}
+
 // CHECK-LABEL: sil [no_locks] [perf_constraint] [ossa] @remove_metatype_arg_throws :
 // CHECK:         [[F:%.*]] = function_ref @$s19metatype_arg_throwsTf4ndn_n : $@convention(thin) (Int, @owned Builtin.NativeObject) -> (@owned Builtin.NativeObject, @error any Error)
 // CHECK:         try_apply [[F]](%0, %1) : $@convention(thin) (Int, @owned Builtin.NativeObject) -> (@owned Builtin.NativeObject, @error any Error), normal bb1, error bb2