test/SILOptimizer/dead_code_elimination.sil

// RUN: %target-sil-opt -enable-sil-verify-all -dce %s | %FileCheck %s

sil_stage canonical

import Builtin
import Swift

// CHECK-LABEL: sil @dead1
sil @dead1 : $@convention(thin) (Int32, Int32) -> Int32 {
// CHECK: bb0
bb0(%0 : $Int32, %1 : $Int32):
  %3 = struct_extract %0 : $Int32, #Int32._value
  %4 = struct_extract %1 : $Int32, #Int32._value
  %5 = integer_literal $Builtin.Int1, -1
  %6 = builtin "sadd_with_overflow_Int32"(%3 : $Builtin.Int32, %4 : $Builtin.Int32, %5 : $Builtin.Int1) : $(Builtin.Int32, Builtin.Int1)
  %7 = tuple_extract %6 : $(Builtin.Int32, Builtin.Int1), 0
  %8 = struct $Int32 (%7 : $Builtin.Int32)
// CHECK-NEXT: return %0
  return %0 : $Int32
}

// CHECK-LABEL: sil @dead2
sil @dead2 : $@convention(thin) () -> () {
// CHECK: bb0
bb0:
// CHECK-NOT: integer_literal $Builtin.Int32, 2
  %0 = integer_literal $Builtin.Int32, 2
// CHECK-NOT: integer_literal $Builtin.Int32, 0
  %1 = integer_literal $Builtin.Int32, 0
// CHECK-NEXT: br bb1
  br bb1(%0 : $Builtin.Int32, %1 : $Builtin.Int32)

// CHECK: bb1
bb1(%3 : $Builtin.Int32, %4 : $Builtin.Int32):
// CHECK-NEXT: br bb3
  %5 = integer_literal $Builtin.Int32, 100
  %7 = builtin "cmp_slt_Int32"(%4 : $Builtin.Int32, %5 : $Builtin.Int32) : $Builtin.Int1
  cond_br %7, bb2, bb3

// CHECK: bb2
bb2:
// CHECK-NEXT: br bb1
  %9 = integer_literal $Builtin.Int32, 3
  %11 = integer_literal $Builtin.Int1, -1
  %12 = builtin "sadd_with_overflow_Int32"(%3 : $Builtin.Int32, %9 : $Builtin.Int32, %11 : $Builtin.Int1) : $(Builtin.Int32, Builtin.Int1)
  %13 = tuple_extract %12 : $(Builtin.Int32, Builtin.Int1), 0
  %14 = integer_literal $Builtin.Int32, 1
  %15 = builtin "sadd_with_overflow_Int32"(%4 : $Builtin.Int32, %14 : $Builtin.Int32, %11 : $Builtin.Int1) : $(Builtin.Int32, Builtin.Int1)
  %16 = tuple_extract %15 : $(Builtin.Int32, Builtin.Int1), 0
  br bb1(%13 : $Builtin.Int32, %16 : $Builtin.Int32)

// CHECK: bb3
bb3:
// CHECK-NEXT: [[RESULT:%[a-zA-Z0-9]+]] = tuple ()
  %18 = tuple ()
// CHECK-NEXT: return [[RESULT]]
  return %18 : $()
}

// CHECK-LABEL: sil @dead3
sil @dead3 : $@convention(thin) () -> () {
bb0:
// CHECK: bb0
  br bb1
// CHECK: bb1
bb1:
// CHECK:      bb1:
// CHECK-NEXT:   br bb1
  %0 = integer_literal $Builtin.Int32, 0
  br bb1
}

// CHECK-LABEL: sil hidden @test_dce_bbargs
sil hidden @test_dce_bbargs : $@convention(thin) () -> () {
bb0:
  %0 = integer_literal $Builtin.Int32, 0
  %1 = struct $Int32 (%0 : $Builtin.Int32)
  %2 = integer_literal $Builtin.Int32, 0
  %3 = struct $Int32 (%2 : $Builtin.Int32)
  %4 = integer_literal $Builtin.Int32, 0
  %5 = struct $Int32 (%4 : $Builtin.Int32)
  %6 = integer_literal $Builtin.Int32, 0
  %7 = struct $Int32 (%6 : $Builtin.Int32)
  %8 = integer_literal $Builtin.Int32, 0
  %9 = struct $Int32 (%8 : $Builtin.Int32)
  %10 = integer_literal $Builtin.Int32, 0
  %11 = struct $Int32 (%10 : $Builtin.Int32)
  br bb1(%1 : $Int32, %3 : $Int32, %11 : $Int32, %7 : $Int32, %9 : $Int32)

bb1(%13 : $Int32, %14 : $Int32, %15 : $Int32, %16 : $Int32, %17 : $Int32):
  %18 = integer_literal $Builtin.Int32, 11
  %20 = struct_extract %15 : $Int32, #Int32._value
  %21 = builtin "cmp_slt_Int32"(%20 : $Builtin.Int32, %18 : $Builtin.Int32) : $Builtin.Int1
  %22 = struct $Bool (%21 : $Builtin.Int1)
  %23 = struct_extract %22 : $Bool, #Bool._value
  cond_br %23, bb2, bb10

// CHECK: bb2:
bb2:
  %25 = integer_literal $Builtin.Int32, 0
  %26 = struct $Int32 (%25 : $Builtin.Int32)
// br bb3(undef : $Int32, undef : $Int32,
  br bb3(%13 : $Int32, %14 : $Int32, %26 : $Int32, %17 : $Int32)

bb3(%28 : $Int32, %29 : $Int32, %30 : $Int32, %31 : $Int32):
  %32 = integer_literal $Builtin.Int32, 22
  %34 = struct_extract %30 : $Int32, #Int32._value
  %35 = builtin "cmp_slt_Int32"(%34 : $Builtin.Int32, %32 : $Builtin.Int32) : $Builtin.Int1
  %36 = struct $Bool (%35 : $Builtin.Int1)
  %37 = struct_extract %36 : $Bool, #Bool._value
  cond_br %37, bb4, bb9

// CHECK: bb4:
bb4:
  %39 = integer_literal $Builtin.Int32, 0
  %41 = struct_extract %28 : $Int32, #Int32._value
  %42 = builtin "cmp_eq_Int32"(%39 : $Builtin.Int32, %41 : $Builtin.Int32) : $Builtin.Int1
  %43 = struct $Bool (%42 : $Builtin.Int1)
  %44 = struct_extract %43 : $Bool, #Bool._value
// CHECK-NOT: cond_br
// CHECK: br bb8
  cond_br %44, bb5, bb6(%28 : $Int32)

bb5:
  %46 = integer_literal $Builtin.Int32, 0
  %47 = struct $Int32 (%46 : $Builtin.Int32)
  br bb6(%47 : $Int32)

// CHECK: bb6{{.*}}):
bb6(%49 : $Int32):
  %50 = integer_literal $Builtin.Int32, 10
  %52 = struct_extract %29 : $Int32, #Int32._value
  %53 = builtin "cmp_eq_Int32"(%50 : $Builtin.Int32, %52 : $Builtin.Int32) : $Builtin.Int1
  %54 = struct $Bool (%53 : $Builtin.Int1)
  %55 = struct_extract %54 : $Bool, #Bool._value
// CHECK-NOT: cond_br
// CHECK: br bb8
  cond_br %55, bb7, bb8(%29 : $Int32)

// CHECK: bb7:
bb7:
  %57 = integer_literal $Builtin.Int32, 0
  %58 = struct $Int32 (%57 : $Builtin.Int32)
// CHECK: br bb8
  br bb8(%58 : $Int32)

// CHECK: bb8(%{{[0-9]+}} : $Int32):
bb8(%60 : $Int32):
  %61 = struct_extract %31 : $Int32, #Int32._value
  %62 = integer_literal $Builtin.Int32, 1
  %64 = integer_literal $Builtin.Int1, -1
// CHECK-NOT: builtin "sadd_with_overflow_Int32"
// CHECK-NOT: cond_fail
  %65 = builtin "sadd_with_overflow_Int32"(%61 : $Builtin.Int32, %62 : $Builtin.Int32, %64 : $Builtin.Int1) : $(Builtin.Int32, Builtin.Int1)
  %66 = tuple_extract %65 : $(Builtin.Int32, Builtin.Int1), 0
  %67 = tuple_extract %65 : $(Builtin.Int32, Builtin.Int1), 1
  cond_fail %67 : $Builtin.Int1
  %69 = struct $Int32 (%66 : $Builtin.Int32)
  %70 = struct_extract %30 : $Int32, #Int32._value
  %71 = integer_literal $Builtin.Int32, 1
  %73 = integer_literal $Builtin.Int1, -1
// CHECK: builtin "ssub_with_overflow_Int32"
  %74 = builtin "ssub_with_overflow_Int32"(%70 : $Builtin.Int32, %71 : $Builtin.Int32, %73 : $Builtin.Int1) : $(Builtin.Int32, Builtin.Int1)
  %75 = tuple_extract %74 : $(Builtin.Int32, Builtin.Int1), 0
  %76 = tuple_extract %74 : $(Builtin.Int32, Builtin.Int1), 1
// CHECK: cond_fail
  cond_fail %76 : $Builtin.Int1
  %78 = struct $Int32 (%75 : $Builtin.Int32)
  %tif = function_ref @take_int32 : $@convention(thin) (Int32) -> ()
  %atif = apply %tif(%78) : $@convention(thin) (Int32) -> ()
// CHECK: br bb3(undef : $Int32, undef : $Int32,
  br bb3(%49 : $Int32, %60 : $Int32, %78 : $Int32, %69 : $Int32)

// CHECK: bb9:
bb9:
  %80 = struct_extract %15 : $Int32, #Int32._value
  %81 = integer_literal $Builtin.Int32, 1
  %83 = integer_literal $Builtin.Int1, -1
  %84 = builtin "sadd_with_overflow_Int32"(%80 : $Builtin.Int32, %81 : $Builtin.Int32, %83 : $Builtin.Int1) : $(Builtin.Int32, Builtin.Int1)
  %85 = tuple_extract %84 : $(Builtin.Int32, Builtin.Int1), 0
  %86 = tuple_extract %84 : $(Builtin.Int32, Builtin.Int1), 1
  cond_fail %86 : $Builtin.Int1
  %88 = struct $Int32 (%85 : $Builtin.Int32)
// CHECK: br bb1(undef : $Int32, undef : $Int32,
  br bb1(%28 : $Int32, %29 : $Int32, %88 : $Int32, %30 : $Int32, %31 : $Int32)

// CHECK: bb10:
bb10:
  %90 = tuple ()
// CHECK: return
  return %90 : $()
}

sil @take_int32 : $@convention(thin) (Int32) -> ()

// CHECK-LABEL: sil @remove_fix_lifetime
// CHECK: bb0:
// CHECK-NEXT: tuple
// CHECK-NEXT: return
sil @remove_fix_lifetime : $@convention(thin) () -> () {
bb0:
  %0 = integer_literal $Builtin.Int32, 0
  %1 = struct $Int32 (%0 : $Builtin.Int32)

  fix_lifetime %1 : $Int32
  fix_lifetime %1 : $Int32

  %90 = tuple ()
  return %90 : $()
}

// CHECK-LABEL: sil @dont_remove_fix_lifetime
// CHECK: fix_lifetime
// CHECK: fix_lifetime
// CHECK: return
sil @dont_remove_fix_lifetime : $@convention(thin) () -> Int32 {
bb0:
  %0 = integer_literal $Builtin.Int32, 0
  %1 = struct $Int32 (%0 : $Builtin.Int32)

  fix_lifetime %1 : $Int32
  fix_lifetime %1 : $Int32

  return %1 : $Int32
}

struct Container {
	var i: Int32
}

// CHECK-LABEL: sil @dont_remove_addr_fix_lifetime
// CHECK: fix_lifetime
// CHECK: fix_lifetime
// CHECK: return
sil @dont_remove_addr_fix_lifetime : $@convention(thin) (@in Container) -> () {
bb0(%0 : $*Container):
  %1 = struct_element_addr %0 : $*Container, #Container.i

  fix_lifetime %1 : $*Int32
  fix_lifetime %1 : $*Int32

  %90 = tuple ()
  return %90 : $()
}

// Check that DCE does not crash with an infinite loop through a cond_br.
// CHECK-LABEL: sil @deal_with_infinite_loop
// CHECK: cond_br
sil @deal_with_infinite_loop : $@convention(thin) () -> () {
bb0:
  br bb1

bb1:
  cond_br undef, bb2, bb3

bb2:
  br bb1

bb3:
  br bb1
}