Skip to content

Commit eea590a

Browse files
hamishknighthamishknight
committed
[SILGen] Remove mark_uninitialized for if/switch expr branches
We always immediately emit an expression into the initialization, so this isn't providing much value.
1 parent 75c5fc5 commit eea590a

File tree

3 files changed

+56
-87
lines changed

3 files changed

+56
-87
lines changed

‎lib/SILGen/SILGenFunction.cpp

Lines changed: 1 addition & 8 deletions
Original file line numberDiff line numberDiff line change
@@ -1693,15 +1693,8 @@ std::unique_ptr<Initialization> SILGenFunction::getSingleValueStmtInit(Expr *E)
16931693
// SingleValueStmtExpr initialization.
16941694
if (!SingleValueStmtInitStack.back().Exprs.contains(E))
16951695
return nullptr;
1696-
1697-
// This won't give us a useful diagnostic if the result doesn't end up
1698-
// initialized ("variable '<unknown>' used before being initialized"), but it
1699-
// will at least catch a potential miscompile when the SIL verifier is
1700-
// disabled.
1696+
17011697
auto resultAddr = SingleValueStmtInitStack.back().InitializationBuffer;
1702-
resultAddr = B.createMarkUninitialized(
1703-
E, resultAddr, MarkUninitializedInst::Kind::Var);
1704-
17051698
return std::make_unique<KnownAddressInitialization>(resultAddr);
17061699
}
17071700

‎test/SILGen/if_expr.swift

Lines changed: 25 additions & 34 deletions
Original file line numberDiff line numberDiff line change
@@ -6,26 +6,24 @@ func foo() -> Int {
66
}
77

88
// CHECK-LABEL: sil hidden [ossa] @$s7if_expr3fooSiyF : $@convention(thin) () -> Int
9-
// CHECK: [[RESULT_STORAGE:%[0-9]+]] = alloc_stack $Int
9+
// CHECK: [[RESULT:%[0-9]+]] = alloc_stack $Int
1010
// CHECK: cond_br {{%[0-9]+}}, [[TRUEBB:bb[0-9]+]], [[FALSEBB:bb[0-9]+]]
1111
//
1212
// CHECK: [[TRUEBB]]:
13-
// CHECK: [[RESULT:%[0-9]+]] = mark_uninitialized [var] [[RESULT_STORAGE]] : $*Int
1413
// CHECK: [[ONE_BUILTIN:%[0-9]+]] = integer_literal $Builtin.IntLiteral, 1
1514
// CHECK: [[ONE:%[0-9]+]] = apply {{%[0-9]+}}([[ONE_BUILTIN]], {{%[0-9]+}}) : $@convention(method) (Builtin.IntLiteral, @thin Int.Type) -> Int
1615
// CHECK: store [[ONE]] to [trivial] [[RESULT]] : $*Int
1716
// CHECK: br [[EXITBB:bb[0-9]+]]
1817
//
1918
// CHECK: [[FALSEBB]]:
20-
// CHECK: [[RESULT:%[0-9]+]] = mark_uninitialized [var] [[RESULT_STORAGE]] : $*Int
2119
// CHECK: [[TWO_BUILTIN:%[0-9]+]] = integer_literal $Builtin.IntLiteral, 2
2220
// CHECK: [[TWO:%[0-9]+]] = apply {{%[0-9]+}}([[TWO_BUILTIN]], {{%[0-9]+}}) : $@convention(method) (Builtin.IntLiteral, @thin Int.Type) -> Int
2321
// CHECK: store [[TWO]] to [trivial] [[RESULT]] : $*Int
2422
// CHECK: br [[EXITBB]]
2523
//
2624
// CHECK: [[EXITBB]]:
27-
// CHECK: [[VAL:%[0-9]+]] = load [trivial] [[RESULT_STORAGE]] : $*Int
28-
// CHECK: dealloc_stack [[RESULT_STORAGE]] : $*Int
25+
// CHECK: [[VAL:%[0-9]+]] = load [trivial] [[RESULT]] : $*Int
26+
// CHECK: dealloc_stack [[RESULT]] : $*Int
2927
// CHECK: return [[VAL]] : $Int
3028

3129
class C {}
@@ -36,25 +34,23 @@ func bar(_ x: C) -> C {
3634

3735
// CHECK-LABEL: sil hidden [ossa] @$s7if_expr3baryAA1CCADF : $@convention(thin) (@guaranteed C) -> @owned C
3836
// CHECK: bb0([[CPARAM:%[0-9]+]] : @guaranteed $C):
39-
// CHECK: [[RESULT_STORAGE:%[0-9]+]] = alloc_stack $C
37+
// CHECK: [[RESULT:%[0-9]+]] = alloc_stack $C
4038
// CHECK: cond_br {{%[0-9]+}}, [[TRUEBB:bb[0-9]+]], [[FALSEBB:bb[0-9]+]]
4139
//
4240
// CHECK: [[TRUEBB]]:
43-
// CHECK: [[RESULT:%[0-9]+]] = mark_uninitialized [var] [[RESULT_STORAGE]] : $*C
4441
// CHECK: [[C:%[0-9]+]] = copy_value [[CPARAM]] : $C
4542
// CHECK: store [[C]] to [init] [[RESULT]] : $*C
4643
// CHECK: br [[EXITBB:bb[0-9]+]]
4744
//
4845
// CHECK: [[FALSEBB]]:
49-
// CHECK: [[RESULT:%[0-9]+]] = mark_uninitialized [var] [[RESULT_STORAGE]] : $*C
5046
// CHECK: [[CTOR:%[0-9]+]] = function_ref @$s7if_expr1CCACycfC : $@convention(method) (@thick C.Type) -> @owned C
5147
// CHECK: [[C:%[0-9]+]] = apply [[CTOR]]({{%[0-9]+}}) : $@convention(method) (@thick C.Type) -> @owned C
5248
// CHECK: store [[C]] to [init] [[RESULT]] : $*C
5349
// CHECK: br [[EXITBB]]
5450
//
5551
// CHECK: [[EXITBB]]:
56-
// CHECK: [[VAL:%[0-9]+]] = load [take] [[RESULT_STORAGE]] : $*C
57-
// CHECK: dealloc_stack [[RESULT_STORAGE]] : $*C
52+
// CHECK: [[VAL:%[0-9]+]] = load [take] [[RESULT]] : $*C
53+
// CHECK: dealloc_stack [[RESULT]] : $*C
5854
// CHECK: return [[VAL]] : $C
5955

6056
struct Err: Error {}
@@ -70,7 +66,7 @@ func baz() throws -> Int {
7066
}
7167

7268
// CHECK-LABEL: sil hidden [ossa] @$s7if_expr3bazSiyKF : $@convention(thin) () -> (Int, @error any Error)
73-
// CHECK: [[RESULT_STORAGE:%[0-9]+]] = alloc_stack $Int
69+
// CHECK: [[RESULT:%[0-9]+]] = alloc_stack $Int
7470
// CHECK: cond_br {{%[0-9]+}}, [[TRUEBB:bb[0-9]+]], [[FALSEBB:bb[0-9]+]]
7571
//
7672
// CHECK: [[FALSEBB]]:
@@ -83,33 +79,32 @@ func baz() throws -> Int {
8379
// CHECK: br [[EXITBB:bb[0-9]+]]
8480
//
8581
// CHECK: [[EXITBB]]:
86-
// CHECK: [[VAL:%[0-9]+]] = load [trivial] [[RESULT_STORAGE]] : $*Int
87-
// CHECK: dealloc_stack [[RESULT_STORAGE]] : $*Int
82+
// CHECK: [[VAL:%[0-9]+]] = load [trivial] [[RESULT]] : $*Int
83+
// CHECK: dealloc_stack [[RESULT]] : $*Int
8884
// CHECK: return [[VAL]] : $Int
8985

9086
func qux() throws -> Int {
9187
if .random() { 0 } else { try baz() }
9288
}
9389

9490
// CHECK-LABEL: sil hidden [ossa] @$s7if_expr3quxSiyKF : $@convention(thin) () -> (Int, @error any Error)
95-
// CHECK: [[RESULT_STORAGE:%[0-9]+]] = alloc_stack $Int
91+
// CHECK: [[RESULT:%[0-9]+]] = alloc_stack $Int
9692
// CHECK: cond_br {{%[0-9]+}}, [[TRUEBB:bb[0-9]+]], [[FALSEBB:bb[0-9]+]]
9793
//
9894
// CHECK: [[FALSEBB]]:
99-
// CHECK: [[RESULT:%[0-9]+]] = mark_uninitialized [var] [[RESULT_STORAGE]] : $*Int
10095
// CHECK: try_apply {{%[0-9]+}}() : $@convention(thin) () -> (Int, @error any Error), normal [[NORMALBB:bb[0-9]+]], error [[ERRORBB:bb[0-9]+]]
10196
//
10297
// CHECK: [[NORMALBB]]([[BAZVAL:%[0-9]+]] : $Int):
10398
// CHECK: store [[BAZVAL]] to [trivial] [[RESULT]] : $*Int
10499
// CHECK: br [[EXITBB:bb[0-9]+]]
105100
//
106101
// CHECK: [[EXITBB]]:
107-
// CHECK: [[VAL:%[0-9]+]] = load [trivial] [[RESULT_STORAGE]] : $*Int
108-
// CHECK: dealloc_stack [[RESULT_STORAGE]] : $*Int
102+
// CHECK: [[VAL:%[0-9]+]] = load [trivial] [[RESULT]] : $*Int
103+
// CHECK: dealloc_stack [[RESULT]] : $*Int
109104
// CHECK: return [[VAL]] : $Int
110105
//
111106
// CHECK: [[ERRORBB]]([[ERR:%[0-9]+]] : @owned $any Error):
112-
// CHECK: dealloc_stack [[RESULT_STORAGE]] : $*Int
107+
// CHECK: dealloc_stack [[RESULT]] : $*Int
113108
// CHECK: throw [[ERR]] : $any Error
114109

115110
func optionalVoidCrash() {
@@ -141,24 +136,23 @@ func testClosure() throws -> Int {
141136
}
142137

143138
// CHECK-LABEL: sil private [ossa] @$s7if_expr11testClosureSiyKFSiyKcfU_ : $@convention(thin) () -> (Int, @error any Error)
144-
// CHECK: [[RESULT_STORAGE:%[0-9]+]] = alloc_stack $Int
139+
// CHECK: [[RESULT:%[0-9]+]] = alloc_stack $Int
145140
// CHECK: cond_br {{%[0-9]+}}, [[TRUEBB:bb[0-9]+]], [[FALSEBB:bb[0-9]+]]
146141
//
147142
// CHECK: [[FALSEBB]]:
148-
// CHECK: [[RESULT:%[0-9]+]] = mark_uninitialized [var] [[RESULT_STORAGE]] : $*Int
149143
// CHECK: try_apply {{%[0-9]+}}() : $@convention(thin) () -> (Int, @error any Error), normal [[NORMALBB:bb[0-9]+]], error [[ERRORBB:bb[0-9]+]]
150144
//
151145
// CHECK: [[NORMALBB]]([[BAZVAL:%[0-9]+]] : $Int):
152146
// CHECK: store [[BAZVAL]] to [trivial] [[RESULT]] : $*Int
153147
// CHECK: br [[EXITBB:bb[0-9]+]]
154148
//
155149
// CHECK: [[EXITBB]]:
156-
// CHECK: [[VAL:%[0-9]+]] = load [trivial] [[RESULT_STORAGE]] : $*Int
157-
// CHECK: dealloc_stack [[RESULT_STORAGE]] : $*Int
150+
// CHECK: [[VAL:%[0-9]+]] = load [trivial] [[RESULT]] : $*Int
151+
// CHECK: dealloc_stack [[RESULT]] : $*Int
158152
// CHECK: return [[VAL]] : $Int
159153
//
160154
// CHECK: [[ERRORBB]]([[ERR:%[0-9]+]] : @owned $any Error):
161-
// CHECK: dealloc_stack [[RESULT_STORAGE]] : $*Int
155+
// CHECK: dealloc_stack [[RESULT]] : $*Int
162156
// CHECK: throw [[ERR]] : $any Error
163157

164158
func testNested() throws -> Int {
@@ -174,7 +168,7 @@ func testNested() throws -> Int {
174168
}
175169

176170
// CHECK-LABEL: sil hidden [ossa] @$s7if_expr10testNestedSiyKF : $@convention(thin) () -> (Int, @error any Error)
177-
// CHECK: [[RESULT_STORAGE:%[0-9]+]] = alloc_stack $Int
171+
// CHECK: [[RESULT:%[0-9]+]] = alloc_stack $Int
178172
// CHECK: cond_br {{%[0-9]+}}, [[TRUEBB:bb[0-9]+]], [[FALSEBB:bb[0-9]+]]
179173
//
180174
// CHECK: [[FALSEBB]]:
@@ -187,8 +181,8 @@ func testNested() throws -> Int {
187181
// CHECK: br [[EXITBB:bb[0-9]+]]
188182
//
189183
// CHECK: [[EXITBB]]:
190-
// CHECK: [[VAL:%[0-9]+]] = load [trivial] [[RESULT_STORAGE]] : $*Int
191-
// CHECK: dealloc_stack [[RESULT_STORAGE]] : $*Int
184+
// CHECK: [[VAL:%[0-9]+]] = load [trivial] [[RESULT]] : $*Int
185+
// CHECK: dealloc_stack [[RESULT]] : $*Int
192186
// CHECK: return [[VAL]] : $Int
193187

194188
func testVar() -> Int {
@@ -517,18 +511,17 @@ func testNever3() -> Int {
517511
}
518512
}
519513
// CHECK-LABEL: sil hidden [ossa] @$s7if_expr10testNever3SiyF : $@convention(thin) () -> Int
520-
// CHECK: [[RESULT_STORAGE:%[0-9]+]] = alloc_stack $Int
514+
// CHECK: [[RESULT:%[0-9]+]] = alloc_stack $Int
521515
// CHECK: cond_br {{%[0-9]+}}, [[BB_TRUE:bb[0-9]+]], [[BB_FALSE:bb[0-9]+]]
522516
//
523517
// CHECK: [[BB_TRUE]]:
524518
// CHECK: function_ref fatalError(_:file:line:)
525519
// CHECK: unreachable
526520
//
527521
// CHECK: [[BB_FALSE]]:
528-
// CHECK: [[RESULT:%[0-9]+]] = mark_uninitialized [var] [[RESULT_STORAGE]] : $*Int
529522
// CHECK: store {{%[0-9]+}} to [trivial] [[RESULT]] : $*Int
530-
// CHECK: [[RET:%[0-9]+]] = load [trivial] [[RESULT_STORAGE]] : $*Int
531-
// CHECK: dealloc_stack [[RESULT_STORAGE]] : $*Int
523+
// CHECK: [[RET:%[0-9]+]] = load [trivial] [[RESULT]] : $*Int
524+
// CHECK: dealloc_stack [[RESULT]] : $*Int
532525
// CHECK: return [[RET]]
533526

534527
func never() -> Never { fatalError() }
@@ -551,11 +544,10 @@ func testNever5() -> (Never, Int) {
551544
}
552545
}
553546
// CHECK-LABEL: sil hidden [ossa] @$s7if_expr10testNever5s5NeverO_SityF : $@convention(thin) () -> (Never, Int)
554-
// CHECK: [[RESULT_STORAGE:%[0-9]+]] = alloc_stack $(Never, Int)
547+
// CHECK: [[RESULT:%[0-9]+]] = alloc_stack $(Never, Int)
555548
// CHECK: cond_br {{%[0-9]+}}, [[BB_TRUE:bb[0-9]+]], [[BB_FALSE:bb[0-9]+]]
556549
//
557550
// CHECK: [[BB_TRUE]]:
558-
// CHECK: [[RESULT:%[0-9]+]] = mark_uninitialized [var] [[RESULT_STORAGE]] : $*(Never, Int)
559551
// CHECK: [[ELT_0:%[0-9]+]] = tuple_element_addr [[RESULT]] : $*(Never, Int), 0
560552
// CHECK: [[ELT_1:%[0-9]+]] = tuple_element_addr [[RESULT]] : $*(Never, Int), 1
561553
// CHECK: ([[RET_0:%[0-9]+]], [[RET_1:%[0-9]+]]) = destructure_tuple {{%[0-9]+}} : $(Never, Int)
@@ -564,15 +556,14 @@ func testNever5() -> (Never, Int) {
564556
// CHECK: br [[BB_EXIT:bb[0-9]+]]
565557
//
566558
// CHECK: [[BB_FALSE]]:
567-
// CHECK: [[RESULT:%[0-9]+]] = mark_uninitialized [var] [[RESULT_STORAGE]] : $*(Never, Int)
568559
// CHECK: [[ELT_0:%[0-9]+]] = tuple_element_addr [[RESULT]] : $*(Never, Int), 0
569560
// CHECK: [[ELT_1:%[0-9]+]] = tuple_element_addr [[RESULT]] : $*(Never, Int), 1
570561
// CHECK: store {{%[0-9]+}} to [trivial] [[ELT_0]] : $*Never
571562
// CHECK: store {{%[0-9]+}} to [trivial] [[ELT_1]] : $*Int
572563
// CHECK: br [[BB_EXIT:bb[0-9]+]]
573564
//
574565
// CHECK: [[BB_EXIT]]:
575-
// CHECK: dealloc_stack [[RESULT_STORAGE]] : $*(Never, Int)
566+
// CHECK: dealloc_stack [[RESULT]] : $*(Never, Int)
576567
// CHECK: [[RET:%[0-9]+]] = tuple ({{%[0-9]+}} : $Never, {{%[0-9]+}} : $Int)
577568
// CHECK: return [[RET]]
578569

0 commit comments

Comments
 (0)