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// RUN: %target-swift-emit-silgen %s | %FileCheck %s
// Some fake predicates for pattern guards.
func runced() -> Bool { return true }
func funged() -> Bool { return true }
func ansed() -> Bool { return true }
func foo() -> Int { return 0 }
func bar() -> Int { return 0 }
func a() {}
func b() {}
func c() {}
func d() {}
func e() {}
func f() {}
func g() {}
func z(_ i: Int) {}
// CHECK-LABEL: sil hidden [ossa] @$s18switch_fallthrough5test1yyF
func test1() {
switch foo() {
// CHECK: cond_br {{%.*}}, [[YES_CASE1:bb[0-9]+]], {{bb[0-9]+}}
// CHECK: [[YES_CASE1]]:
case foo():
// CHECK: function_ref @$s18switch_fallthrough1ayyF
// CHECK: br [[CASE2:bb[0-9]+]]
a()
fallthrough
case bar():
// CHECK: [[CASE2]]:
// CHECK: function_ref @$s18switch_fallthrough1byyF
// CHECK: br [[CASE3:bb[0-9]+]]
b()
fallthrough
case _:
// CHECK: [[CASE3]]:
// CHECK: function_ref @$s18switch_fallthrough1cyyF
c()
}
// CHECK: function_ref @$s18switch_fallthrough1dyyF
d()
}
// Fallthrough should work even if the next case is normally unreachable
// CHECK-LABEL: sil hidden [ossa] @$s18switch_fallthrough5test2yyF
func test2() {
switch foo() {
// CHECK: cond_br {{%.*}}, [[YES_CASE1:bb[0-9]+]], {{bb[0-9]+}}
// CHECK: [[YES_CASE1]]:
case foo():
// CHECK: function_ref @$s18switch_fallthrough1ayyF
// CHECK: br [[CASE2:bb[0-9]+]]
a()
fallthrough
case _:
// CHECK: [[CASE2]]:
// CHECK: function_ref @$s18switch_fallthrough1byyF
// CHECK: br [[CASE3:bb[0-9]+]]
b()
fallthrough
case _:
// CHECK: [[CASE3]]:
// CHECK: function_ref @$s18switch_fallthrough1cyyF
c()
}
// CHECK: function_ref @$s18switch_fallthrough1dyyF
d()
}
// CHECK-LABEL: sil hidden [ossa] @$s18switch_fallthrough5test3yyF
func test3() {
switch (foo(), bar()) {
// CHECK: cond_br {{%.*}}, [[YES_CASE1:bb[0-9]+]], {{bb[0-9]+}}
// CHECK: [[YES_CASE1]]:
case (foo(), bar()):
// CHECK: function_ref @$s18switch_fallthrough1ayyF
// CHECK: br [[CASE2:bb[0-9]+]]
a()
fallthrough
case (foo(), _):
// CHECK: [[CASE2]]:
// CHECK: function_ref @$s18switch_fallthrough1byyF
// CHECK: br [[CASE3:bb[0-9]+]]
b()
fallthrough
case (_, _):
// CHECK: [[CASE3]]:
// CHECK: function_ref @$s18switch_fallthrough1cyyF
// CHECK: br [[CASE4:bb[0-9]+]]
c()
fallthrough
case (_, _):
// CHECK: [[CASE4]]:
// CHECK: function_ref @$s18switch_fallthrough1dyyF
d()
}
// CHECK: function_ref @$s18switch_fallthrough1eyyF
e()
}
// Fallthrough should clean up nested pattern variables from the exited scope.
func test4() {
switch (foo(), bar()) {
// CHECK: [[A:%.*]] = alloc_box ${ var (Int, Int) }
// CHECK: cond_br {{%.*}}, [[CASE1:bb[0-9]+]], {{bb[0-9]+}}
case var a where runced():
// CHECK: [[CASE1]]:
// CHECK: br [[CASE2:bb[0-9]+]]
fallthrough
case _ where funged():
// CHECK: [[CASE2]]:
// CHECK: br [[CONT:bb[0-9]+]]
()
// CHECK: [[B:%.*]] = alloc_box ${ var Int }
// CHECK: [[C:%.*]] = alloc_box ${ var Int }
// CHECK: cond_br {{%.*}}, [[CASE4:bb[0-9]+]],
case (var b, var c) where ansed():
// CHECK: [[CASE4]]:
// CHECK: br [[CASE5:bb[0-9]+]]
fallthrough
case _:
// CHECK: [[CASE5]]:
// CHECK: br [[CONT]]
()
}
// CHECK: [[CONT]]:
// CHECK-NEXT: tuple ()
// CHECK-NEXT: return
}
// Fallthrough into case block with binding // CHECK-LABEL: sil hidden [ossa] @$s18switch_fallthrough5test5yyF
func test5() {
switch (foo(), bar()) {
// CHECK: cond_br {{%.*}}, [[YES_CASE1:bb[0-9]+]], {{bb[0-9]+}}
// CHECK: [[YES_CASE1]]:
case (var n, foo()):
// Check that the var is boxed and unboxed and the final value is the one that falls through into the next case
// CHECK: [[BOX:%.*]] = alloc_box ${ var Int }, var, name "n"
// CHECK: [[N_LIFETIME:%.*]] = begin_borrow [var_decl] [[BOX]]
// CHECK: [[N_BOX:%.*]] = project_box [[N_LIFETIME]] : ${ var Int }, 0
// CHECK: function_ref @$s18switch_fallthrough1ayyF
// CHECK: [[N:%.*]] = load [trivial] [[N_BOX]] : $*Int
// CHECK: destroy_value [[BOX]] : ${ var Int }
// CHECK: br [[CASE2:bb[0-9]+]]([[N]] : $Int)
a()
fallthrough
case (foo(), let n):
// CHECK: cond_br {{%.*}}, [[YES_SECOND_CONDITION:bb[0-9]+]], {{bb[0-9]+}}
// CHECK: [[YES_SECOND_CONDITION]]:
// CHECK: br [[CASE2]]([[SECOND_N:%.*]] : $Int)
// CHECK: [[CASE2]]([[INCOMING_N:%.*]] : $Int):
// CHECK: debug_value [[INCOMING_N]] : $Int, let, name "n"
// CHECK: [[Z:%.*]] = function_ref @$s18switch_fallthrough1zyySiF
// CHECK: apply [[Z]]([[INCOMING_N]]) : $@convention(thin) (Int) -> ()
// CHECK: br [[CONT:bb[0-9]+]]
z(n)
case (_, _):
break
}
// CHECK: [[CONT]]:
// CHECK: function_ref @$s18switch_fallthrough1eyyF
e()
}
// rdar://problem/67704651 - crash due to nested fallthrough
func testNestedFallthrough(x: (Int, String), y: (Int, Int)) {
switch x {
case (17, let s):
switch y {
case (42, let i):
print("the answer")
default:
print("nope")
}
fallthrough
case (42, let s):
print("42 and \(s)")
default:
print("done")
}
}
|
