Merge pull request #31077 from apple/revert-30429-optimize/remove-dead-in-mand-combine

Revert "[opt] remove trivially dead instructions in mandatory combine"

Author: xedin

lib/SILOptimizer/Mandatory/MandatoryCombine.cpp

@@ -156,7 +156,6 @@ void MandatoryCombiner::addReachableCodeToWorklist(SILFunction &function) {
       ++iterator;
 
       if (isInstructionTriviallyDead(instruction)) {
-        instModCallbacks.deleteInst(instruction);
         continue;
       }
 

test/AutoDiff/SIL/differentiability_witness_function_inst.sil

@@ -13,7 +13,7 @@
 
 // IRGen test.
 
-// RUN: %target-swift-frontend -emit-ir -Xllvm -sil-disable-pass=MandatoryCombine %s | %FileCheck %s --check-prefix=IRGEN --check-prefix %target-cpu
+// RUN: %target-swift-frontend -emit-ir %s | %FileCheck %s --check-prefix=IRGEN --check-prefix %target-cpu
 // NOTE: `%target-cpu`-specific FileCheck lines exist because lowered function types in LLVM IR differ between architectures.
 
 // NOTE(SR-12090): `shell` is required only to run `sed` as a SR-12090 workaround.

test/ClangImporter/macro_literals.swift

@@ -1,4 +1,4 @@
-// RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -Xllvm -sil-print-debuginfo -Xllvm -sil-disable-pass=MandatoryCombine -emit-sil %s | %FileCheck %s
+// RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -Xllvm -sil-print-debuginfo -emit-sil %s | %FileCheck %s
 
 import macros
 

test/Constraints/keypath_dynamic_member_lookup.swift

@@ -39,20 +39,17 @@ var bottomRight = Point(x: 10, y: 10)
 var lens = Lens(Rectangle(topLeft: topLeft,
                           bottomRight: bottomRight))
 
-// A dummy user of variables.
-func user<T>(_ _: T) {}
-
 // CHECK: function_ref @$s29keypath_dynamic_member_lookup4LensV0B6MemberACyqd__Gs15WritableKeyPathCyxqd__G_tcluig
 // CHECK-NEXT: apply %45<Rectangle, Point>({{.*}})
 // CHECK: function_ref @$s29keypath_dynamic_member_lookup4LensV0B6MemberACyqd__Gs7KeyPathCyxqd__G_tcluig
 // CHECK-NEXT: apply %54<Point, Int>({{.*}})
-user(lens.topLeft.x)
+_ = lens.topLeft.x
 
-// CHECK: [[LOOKUP_REF1:%.*]] = function_ref @$s29keypath_dynamic_member_lookup4LensV0B6MemberACyqd__Gs15WritableKeyPathCyxqd__G_tcluig
-// CHECK-NEXT: apply [[LOOKUP_REF1]]<Rectangle, Point>({{.*}})
-// CHECK: [[LOOKUP_REF2:%.*]] = function_ref @$s29keypath_dynamic_member_lookup4LensV0B6MemberACyqd__Gs15WritableKeyPathCyxqd__G_tcluig
-// CHECK-NEXT: apply [[LOOKUP_REF2]]<Point, Int>({{.*}})
-user(lens.topLeft.y)
+// CHECK: function_ref @$s29keypath_dynamic_member_lookup4LensV0B6MemberACyqd__Gs15WritableKeyPathCyxqd__G_tcluig
+// CHECK-NEXT: apply %69<Rectangle, Point>({{.*}})
+// CHECK: function_ref @$s29keypath_dynamic_member_lookup4LensV0B6MemberACyqd__Gs15WritableKeyPathCyxqd__G_tcluig
+// CHECK-NEXT: apply %76<Point, Int>({{.*}})
+_ = lens.topLeft.y
 
 lens.topLeft = Lens(Point(x: 1, y: 2)) // Ok
 lens.bottomRight.y = Lens(12)          // Ok
@@ -241,7 +238,7 @@ func test_recursive_dynamic_lookup(_ lens: Lens<Lens<Point>>) {
   // CHECK: [[FIRST_OBJ:%.*]] = struct_extract {{.*}} : $Lens<Lens<Point>>, #Lens.obj
   // CHECK-NEXT: [[SECOND_OBJ:%.*]] = struct_extract [[FIRST_OBJ]] : $Lens<Point>, #Lens.obj
   // CHECK-NEXT: struct_extract [[SECOND_OBJ]] : $Point, #Point.y
-  user(lens.obj.obj.y)
+  _ = lens.obj.obj.y
   // CHECK: keypath $KeyPath<Point, Int>, (root $Point; stored_property #Point.x : $Int)
   // CHECK-NEXT: keypath $KeyPath<Lens<Point>, Lens<Int>>, (root $Lens<Point>; gettable_property $Lens<Int>,  id @$s29keypath_dynamic_member_lookup4LensV0B6MemberACyqd__Gs7KeyPathCyxqd__G_tcluig : {{.*}})
   // CHECK-NEXT: keypath $KeyPath<Lens<Lens<Point>>, Lens<Lens<Int>>>, (root $Lens<Lens<Point>>; gettable_property $Lens<Lens<Int>>,  id @$s29keypath_dynamic_member_lookup4LensV0B6MemberACyqd__Gs7KeyPathCyxqd__G_tcluig : {{.*}})

test/IRGen/access_markers.sil

@@ -33,9 +33,6 @@ bb0(%0 : $A):
   // CHECK-NEXT: getelementptr inbounds %Ts5Int64V, %Ts5Int64V* [[PROPERTY]], i32 0, i32 0
   // CHECK-NEXT: load i64, i64*
   %4 = load %3 : $*Int64
-  // Use %4 so it's not optimized away.
-  // CHECK-NEXT: store
-  store %4 to undef : $*Int64
 
   // CHECK-NEXT: call void @swift_endAccess([[BUFFER]]* [[SCRATCH1]])
   // CHECK-NEXT: [[T0:%.*]] = bitcast [[BUFFER]]* [[SCRATCH1]] to i8*
@@ -51,9 +48,6 @@ bb0(%0 : $A):
   // CHECK-NEXT: getelementptr inbounds %Ts5Int64V, %Ts5Int64V* [[PROPERTY]], i32 0, i32 0
   // CHECK-NEXT: load i64, i64*
   %7 = load %6 : $*Int64
-  // Use %7 so it's not optimized away.
-  // CHECK-NEXT: store
-  store %7 to undef : $*Int64
 
   // CHECK-NEXT: call void @swift_endAccess([[BUFFER]]* [[SCRATCH2]])
   // CHECK-NEXT: [[T0:%.*]] = bitcast [[BUFFER]]* [[SCRATCH2]] to i8*

test/IRGen/dynamic_self.sil

@@ -1,4 +1,4 @@
-// RUN: %target-swift-frontend -Xllvm -sil-disable-pass=MandatoryCombine -emit-ir %s | %FileCheck %s
+// RUN: %target-swift-frontend -emit-ir %s | %FileCheck %s
 
 // REQUIRES: CPU=i386 || CPU=x86_64
 

test/IRGen/enum.sil

@@ -254,8 +254,6 @@ entry(%u : $*Singleton):
   switch_enum_addr %u : $*Singleton, case #Singleton.value!enumelt: dest
 dest:
   %u2 = unchecked_take_enum_data_addr %u : $*Singleton, #Singleton.value!enumelt
-  // Use u2 so it's not optimized away.
-  copy_addr %u2 to undef : $*(Builtin.Int64, Builtin.Int64)
   %x = tuple ()
   return %x : $()
 }
@@ -981,7 +979,6 @@ entry(%u : $*SinglePayloadSpareBit):
 // CHECK-64:   [[DATA_ADDR:%.*]] = bitcast %T4enum21SinglePayloadSpareBitO* %0 to i63*
 x_dest:
   %u2 = unchecked_take_enum_data_addr %u : $*SinglePayloadSpareBit, #SinglePayloadSpareBit.x!enumelt
-  copy_addr %u2 to undef : $*Builtin.Int63
   %a = function_ref @a : $@convention(thin) () -> ()
   apply %a() : $@convention(thin) () -> ()
   br end
@@ -1492,20 +1489,14 @@ entry(%u : $*MultiPayloadNoSpareBits):
 
 x_dest:
   %x = unchecked_take_enum_data_addr %u : $*MultiPayloadNoSpareBits, #MultiPayloadNoSpareBits.x!enumelt
-  // Dummy use of %x so it's not optimized away.
-  copy_addr %x to undef : $*Builtin.Int64
   br end
 
 y_dest:
   %y = unchecked_take_enum_data_addr %u : $*MultiPayloadNoSpareBits, #MultiPayloadNoSpareBits.y!enumelt
-  // Dummy use of %y so it's not optimized away.
-  copy_addr %y to undef : $*Builtin.Int32
   br end
 
 z_dest:
   %z = unchecked_take_enum_data_addr %u : $*MultiPayloadNoSpareBits, #MultiPayloadNoSpareBits.z!enumelt
-  // Dummy use of %z so it's not optimized away.
-  copy_addr %z to undef : $*Builtin.Int63
   br end
 
 a_dest:
@@ -1751,20 +1742,14 @@ entry(%u : $*MultiPayloadOneSpareBit):
 
 x_dest:
   %x = unchecked_take_enum_data_addr %u : $*MultiPayloadOneSpareBit, #MultiPayloadOneSpareBit.x!enumelt
-  // Dummy use of %x so it's not optimized away.
-  copy_addr %x to undef : $*Builtin.Int62
   br end
 
 y_dest:
   %y = unchecked_take_enum_data_addr %u : $*MultiPayloadOneSpareBit, #MultiPayloadOneSpareBit.y!enumelt
-  // Dummy use of %y so it's not optimized away.
-  copy_addr %y to undef : $*Builtin.Int63
   br end
 
 z_dest:
   %z = unchecked_take_enum_data_addr %u : $*MultiPayloadOneSpareBit, #MultiPayloadOneSpareBit.z!enumelt
-  // Dummy use of %z so it's not optimized away.
-  copy_addr %z to undef : $*Builtin.Int61
   br end
 
 a_dest:
@@ -2456,8 +2441,6 @@ entry(%0 : $*DynamicSingleton<T>):
 
 dest:
   %1 = unchecked_take_enum_data_addr %0 : $*DynamicSingleton<T>, #DynamicSingleton.value!enumelt
-  // Dummy use of %1 so it's not optimized away.
-  copy_addr %1 to undef : $*T
   %v = tuple ()
   return %v : $()
 }
@@ -2538,8 +2521,6 @@ entry(%x : $Int32):
   // CHECK-64: [[INT_SHR:%.*]] = lshr i64 [[INT_SHL]], 32
   // CHECK-64: [[INT:%.*]] = trunc i64 [[INT_SHR]] to i32
   %e = unchecked_enum_data %d : $Optional<(Optional<()>, Int32)>, #Optional.some!enumelt
-  // Use %e so it's not optimized away.
-  store %e to undef : $*(Optional<()>, Int32)
   return %d : $Optional<(Optional<()>, Int32)>
 }
 

test/IRGen/enum_dynamic_multi_payload.sil

@@ -285,12 +285,8 @@ sil @dynamic_project : $@convention(thin) <T> () -> @out EitherOr<T, Builtin.Int
 entry(%e : $*EitherOr<T, Builtin.Int64>):
   // CHECK: bitcast [[EITHER_OR]]* %0 to %swift.opaque*
   %l = unchecked_take_enum_data_addr %e : $*EitherOr<T, Builtin.Int64>, #EitherOr.Left!enumelt
-  // Dummy use of %l so that it's not optimized away.
-  copy_addr %l to undef : $*T
   // CHECK: bitcast [[EITHER_OR]]* %0 to i64*
   %r = unchecked_take_enum_data_addr %e : $*EitherOr<T, Builtin.Int64>, #EitherOr.Right!enumelt
-  // Dummy use of %r so that it's not optimized away.
-  copy_addr %r to undef : $*Builtin.Int64
 
   return undef : $()
 }

test/IRGen/enum_future.sil

@@ -258,7 +258,6 @@ entry(%u : $*Singleton):
   switch_enum_addr %u : $*Singleton, case #Singleton.value!enumelt: dest
 dest:
   %u2 = unchecked_take_enum_data_addr %u : $*Singleton, #Singleton.value!enumelt
-  copy_addr %u2 to undef : $*(Builtin.Int64, Builtin.Int64)
   %x = tuple ()
   return %x : $()
 }
@@ -984,7 +983,6 @@ entry(%u : $*SinglePayloadSpareBit):
 // CHECK-64:   [[DATA_ADDR:%.*]] = bitcast %T11enum_future21SinglePayloadSpareBitO* %0 to i63*
 x_dest:
   %u2 = unchecked_take_enum_data_addr %u : $*SinglePayloadSpareBit, #SinglePayloadSpareBit.x!enumelt
-  copy_addr %u2 to undef : $*Builtin.Int63
   %a = function_ref @a : $@convention(thin) () -> ()
   apply %a() : $@convention(thin) () -> ()
   br end
@@ -1495,20 +1493,14 @@ entry(%u : $*MultiPayloadNoSpareBits):
 
 x_dest:
   %x = unchecked_take_enum_data_addr %u : $*MultiPayloadNoSpareBits, #MultiPayloadNoSpareBits.x!enumelt
-  // Use %x so it's not optimized away.
-  copy_addr %x to undef : $*Builtin.Int64
   br end
 
 y_dest:
   %y = unchecked_take_enum_data_addr %u : $*MultiPayloadNoSpareBits, #MultiPayloadNoSpareBits.y!enumelt
-  // Use %y so it's not optimized away.
-  copy_addr %y to undef : $*Builtin.Int32
   br end
 
 z_dest:
   %z = unchecked_take_enum_data_addr %u : $*MultiPayloadNoSpareBits, #MultiPayloadNoSpareBits.z!enumelt
-  // Use %z so it's not optimized away.
-  copy_addr %z to undef : $*Builtin.Int63
   br end
 
 a_dest:
@@ -1754,20 +1746,14 @@ entry(%u : $*MultiPayloadOneSpareBit):
 
 x_dest:
   %x = unchecked_take_enum_data_addr %u : $*MultiPayloadOneSpareBit, #MultiPayloadOneSpareBit.x!enumelt
-  // Use %x so it's not optimized away.
-  copy_addr %x to undef : $*Builtin.Int62
   br end
 
 y_dest:
   %y = unchecked_take_enum_data_addr %u : $*MultiPayloadOneSpareBit, #MultiPayloadOneSpareBit.y!enumelt
-  // Use %y so it's not optimized away.
-  copy_addr %y to undef : $*Builtin.Int63
   br end
 
 z_dest:
   %z = unchecked_take_enum_data_addr %u : $*MultiPayloadOneSpareBit, #MultiPayloadOneSpareBit.z!enumelt
-  // Use %z so it's not optimized away.
-  copy_addr %z to undef : $*Builtin.Int61
   br end
 
 a_dest:
@@ -2459,8 +2445,6 @@ entry(%0 : $*DynamicSingleton<T>):
 
 dest:
   %1 = unchecked_take_enum_data_addr %0 : $*DynamicSingleton<T>, #DynamicSingleton.value!enumelt
-  // Use %1 so it's not optimized away.
-  copy_addr %1 to undef : $*T
   %v = tuple ()
   return %v : $()
 }
@@ -2541,8 +2525,6 @@ entry(%x : $Int32):
   // CHECK-64: [[INT_SHR:%.*]] = lshr i64 [[INT_SHL]], 32
   // CHECK-64: [[INT:%.*]] = trunc i64 [[INT_SHR]] to i32
   %e = unchecked_enum_data %d : $Optional<(Optional<()>, Int32)>, #Optional.some!enumelt
-  // Use %e so it's not optimized away.
-  store %e to undef : $*(Optional<()>, Int32)
   return %d : $Optional<(Optional<()>, Int32)>
 }
 

test/IRGen/existentials.sil

@@ -73,16 +73,12 @@ entry(%w : $*@sil_weak CP?, %a : $CP?):
   // CHECK: [[SRC_WITNESS_ADDR:%.*]] = getelementptr inbounds { %swift.weak, i8** }, { %swift.weak, i8** }* %0, i32 0, i32 1
   // CHECK: [[DEST_WITNESS:%.*]] = load i8**, i8*** [[SRC_WITNESS_ADDR]]
   %b = load_weak [take] %w : $*@sil_weak CP?
-  // Use %b so it isn't removed.
-  store_weak %b to undef : $*@sil_weak CP?
 
   // CHECK: [[SRC_REF_ADDR:%.*]] = getelementptr inbounds { %swift.weak, i8** }, { %swift.weak, i8** }* %0, i32 0, i32 0
   // CHECK: [[DEST_REF:%.*]] = call %swift.refcounted* @swift_weakLoadStrong(%swift.weak* [[SRC_REF_ADDR]])
   // CHECK: [[SRC_WITNESS_ADDR:%.*]] = getelementptr inbounds { %swift.weak, i8** }, { %swift.weak, i8** }* %0, i32 0, i32 1
   // CHECK: [[DEST_WITNESS:%.*]] = load i8**, i8*** [[SRC_WITNESS_ADDR]]
   %c = load_weak        %w : $*@sil_weak CP?
-  // Use %c so it isn't removed.
-  store_weak %c to undef : $*@sil_weak CP?
 
   // CHECK: call { %swift.weak, i8** }* @"$s12existentials2CP_pSgXwWOb"({ %swift.weak, i8** }* %0, { %swift.weak, i8** }* [[V]])
   copy_addr [take] %w to [initialization] %v : $*@sil_weak CP?