test/SILOptimizer/copy_propagation.sil

// RUN: %target-sil-opt -copy-propagation -enable-sil-opaque-values -enable-sil-verify-all %s | %FileCheck %s

sil_stage canonical

import Builtin
import Swift

// Once Mem2Reg supports ownership, it will leave behind extra copies as
// seen in the SIL test below for simple assignment:
// public func testVarAssign<T>(_ t: T) -> T {
//  var u = t
//  return u
// }
// CopyPropagation should leave behind a single copy and no destroys.
//
// CHECK-LABEL: sil [ossa] @testVarAssign : $@convention(thin) <T> (@in_guaranteed T) -> @out T {
// CHECK: bb0(%0 : @guaranteed $T):
// CHECK-NOT: destroy
// CHECK:   [[CPY:%.*]] = copy_value %0 : $T
// CHECK-NOT: destroy
// CHECK:   return [[CPY]] : $T
// CHECK-LABEL: } // end sil function 'testVarAssign'
sil [ossa] @testVarAssign : $@convention(thin) <T> (@in_guaranteed T) -> @out T {
bb0(%0 : @guaranteed $T):
  %1 = copy_value %0 : $T
  %2 = copy_value %1 : $T
  destroy_value %1 : $T
  return %2 : $T
}

// CHECK: sil [ossa] @multiReturnValue : $@convention(thin) <T> (@in_guaranteed T) -> (@out T, @out T) {
// CHECK: bb0(%0 : @guaranteed $T):
// CHECK-NOT: destroy
// CHECK:   [[CPY1:%.*]] = copy_value %0 : $T
// CHECK-NOT: destroy
// CHECK:   [[CPY2:%.*]] = copy_value %0 : $T
// CHECK-NOT: destroy
// CHECK:   [[R:%.*]] = tuple ([[CPY1]] : $T, [[CPY2]] : $T)
// CHECK-NOT: destroy
// CHECK:   return [[R]] : $(T, T)
// CHECK-LABEL: } // end sil function 'multiReturnValue'
sil [ossa] @multiReturnValue : $@convention(thin) <T> (@in_guaranteed T) -> (@out T, @out T) {
bb0(%0 : @guaranteed $T):
  %1 = copy_value %0 : $T
  %2 = copy_value %1 : $T
  %3 = copy_value %1 : $T
  %4 = tuple (%2 : $T, %3 : $T)
  destroy_value %1 : $T
  return %4 : $(T, T)
}

// CHECK-LABEL: sil [ossa] @multiCallResult : $@convention(thin) <T> (@in_guaranteed T) -> @out T {
// CHECK: bb0(%0 : @guaranteed $T):
// CHECK-NEXT: // function_ref multiReturnValue
// CHECK-NEXT: [[F:%.*]] = function_ref @multiReturnValue : $@convention(thin) <τ_0_0> (@in_guaranteed τ_0_0) -> (@out τ_0_0, @out τ_0_0)
// CHECK-NEXT: [[CALL:%.*]] = apply [[F]]<T>(%0) : $@convention(thin) <τ_0_0> (@in_guaranteed τ_0_0) -> (@out τ_0_0, @out τ_0_0)
// CHECK-NEXT: ([[D1:%.*]], [[D2:%.*]]) = destructure_tuple [[CALL]] : $(T, T)
// CHECK-NEXT: destroy_value [[D2]] : $T
// CHECK-NEXT: return [[D1]] : $T
// CHECK-LABEL: } // end sil function 'multiCallResult'
sil [ossa] @multiCallResult : $@convention(thin) <T> (@in_guaranteed T) -> @out T {
bb0(%0 : @guaranteed $T):
  %1 = copy_value %0 : $T
  %2 = function_ref @multiReturnValue : $@convention(thin) <τ_0_0> (@in_guaranteed τ_0_0) -> (@out τ_0_0, @out τ_0_0)
  %3 = apply %2<T>(%1) : $@convention(thin) <τ_0_0> (@in_guaranteed τ_0_0) -> (@out τ_0_0, @out τ_0_0)
  (%4, %5) = destructure_tuple %3 : $(T, T)
  %6 = copy_value %4 : $T
  %7 = copy_value %5 : $T
  destroy_value %1 : $T
  destroy_value %4 : $T
  destroy_value %5 : $T
  destroy_value %7 : $T
  return %6 : $T
}

// CHECK-LABEL: sil [ossa] @testPhi : $@convention(thin) <T> (@in_guaranteed T, @in_guaranteed T, Bool) -> @out T {
// CHECK: bb0(%0 : @guaranteed $T, %1 : @guaranteed $T, %2 : $Bool):
// CHECK-NEXT: %3 = struct_extract %2 : $Bool, #Bool._value
// CHECK-NEXT: cond_br %3, bb1, bb2
//
// CHECK: bb1:
// CHECK-NEXT: %5 = copy_value %0 : $T
// CHECK-NEXT: br bb3(%5 : $T)
//
// CHECK: bb2:
// CHECK-NEXT: %7 = copy_value %1 : $T
// CHECK-NEXT: br bb3(%7 : $T)
//
// CHECK: bb3(%9 : @owned $T):
// CHECK-NEXT: return %9 : $T
// CHECK-LABEL: } // end sil function 'testPhi'
sil [ossa] @testPhi : $@convention(thin) <T> (@in_guaranteed T, @in_guaranteed T, Bool) -> @out T {
bb0(%0 : @guaranteed $T, %1 : @guaranteed $T, %2 : $Bool):
  %3 = copy_value %0 : $T
  %4 = copy_value %1 : $T
  %5 = struct_extract %2 : $Bool, #Bool._value
  cond_br %5, bb1, bb2

bb1:
  %7 = copy_value %3 : $T
  br bb3(%7 : $T)

bb2:
  %9 = copy_value %4 : $T
  br bb3(%9 : $T)

bb3(%11 : @owned $T):
  destroy_value %4 : $T
  destroy_value %3 : $T
  return %11 : $T
}

// CHECK-LABEL: sil [ossa] @testConsume : $@convention(thin) <T> (@in T, @inout T) -> () {
// CHECK: bb0(%0 : @owned $T, %1 : $*T):
//
// The original copy_value is deleted.
// CHECK-NEXT:   debug_value %0 : $T
//
// A new copy_value is inserted before the consuming store.
// CHECK-NEXT:   %3 = copy_value %0 : $T
// CHECK-NEXT:   store %3 to [init] %1 : $*T
//
// The non-consuming use now uses the original value.
// CHECK-NEXT:   debug_value %0 : $T
//
// A new destroy is inserted after the last use.
// CHECK-NEXT:   destroy_value %0 : $T
// CHECK-NEXT:   debug_value_addr %1 : $*T
//
// The original destroy is deleted.
// CHECK-NEXT:   %8 = tuple ()
// CHECK-NEXT:   return %8 : $()
// CHECK-LABEL: // end sil function 'testConsume'
sil [ossa] @testConsume : $@convention(thin) <T> (@in T, @inout T) -> () {
bb0(%arg : @owned $T, %addr : $*T):
  %copy = copy_value %arg : $T
  debug_value %copy : $T
  store %copy to [init] %addr : $*T
  debug_value %arg : $T
  debug_value_addr %addr : $*T
  destroy_value %arg : $T
  %v = tuple ()
  return %v : $()
}

// CHECK-LABEL: sil [ossa] @testDestroyEdge : $@convention(thin) <T> (@in T, @inout T, Builtin.Int1) -> () {
// CHECK: bb0(%0 : @owned $T, %1 : $*T, %2 : $Builtin.Int1):
// CHECK-NEXT:   cond_br %2, bb2, bb1
//
// CHECK: bb1:
//
// The critical edge is split.
// CHECK-NEXT:   destroy_value %0 : $T
// CHECK-NEXT:   br bb3
//
// CHECK: bb2:
// The original copy is deleted.
// CHECK-NEXT:   debug_value %0 : $T
// CHECK-NEXT:   destroy_value %0 : $T
// CHECK-NEXT:   br bb3
//
// CHECK: bb3:
// The original destroy is deleted.
// CHECK-NEXT:   %9 = tuple ()
// CHECK-NEXT:   return %9 : $()
// CHECK-LABEL: } // end sil function 'testDestroyEdge'
sil [ossa] @testDestroyEdge : $@convention(thin) <T> (@in T, @inout T, Builtin.Int1) -> () {
bb0(%arg : @owned $T, %addr : $*T, %z : $Builtin.Int1):
  cond_br %z, bb1, bb2

bb1:
  debug_value %arg : $T
  %copy = copy_value %arg : $T
  destroy_value %copy : $T
  br bb2

bb2:
  destroy_value %arg : $T
  %10 = tuple ()
  return %10 : $()
}

sil [ossa] @takeGuaranteedAndOwnedArg : $@convention(thin) <T> (@in_guaranteed T, @in T) -> ()

// Test the same user instruction with both @guaranteed and @owned operands taking the same copied value.
// We need to keep the value alive to the end of the instruction.
//
// CHECK-LABEL: sil [ossa] @testGuaranteedAndOwnedArg : $@convention(thin) <T> (@in T) -> () {
// CHECK: bb0(%0 : @owned $T):
// CHECK-NEXT: // function_ref takeGuaranteedAndOwnedArg
// CHECK-NEXT: function_ref @takeGuaranteedAndOwnedArg : $@convention(thin) <τ_0_0> (@in_guaranteed τ_0_0, @in τ_0_0) -> ()
// CHECK-NEXT: [[CPY:%.*]] = copy_value %0 : $T
// CHECK-NEXT: apply %{{.*}}<T>(%0, [[CPY]]) : $@convention(thin) <τ_0_0> (@in_guaranteed τ_0_0, @in τ_0_0) -> ()
// CHECK-NEXT: destroy_value %0 : $T
// CHECK-NEXT: return %{{.*}} : $()
// CHECK-LABEL: } // end sil function 'testGuaranteedAndOwnedArg'
sil [ossa] @testGuaranteedAndOwnedArg : $@convention(thin) <T> (@in T) -> () {
bb(%0 : @owned $T):
  %copy = copy_value %0 : $T
  %f = function_ref @takeGuaranteedAndOwnedArg : $@convention(thin) <T> (@in_guaranteed T, @in T) -> ()
  %call = apply %f<T>(%0, %copy) : $@convention(thin) <T> (@in_guaranteed T, @in T) -> ()
  destroy_value %0 : $T
  return %call : $()
}