src/test/mir-opt/match_false_edges.rs

   1 // Copyright 2012-2016 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 // compile-flags: -Z borrowck=mir
  12
  13 fn guard() -> bool {
  14     false
  15 }
  16
  17 fn guard2(_:i32) -> bool {
  18     true
  19 }
  20
  21 // no_mangle to make sure this gets instantiated even in an executable.
  22 #[no_mangle]
  23 pub fn full_tested_match() {
  24     let _ = match Some(42) {
  25         Some(x) if guard() => (1, x),
  26         Some(y) => (2, y),
  27         None => (3, 3),
  28     };
  29 }
  30
  31 // no_mangle to make sure this gets instantiated even in an executable.
  32 #[no_mangle]
  33 pub fn full_tested_match2() {
  34     let _ = match Some(42) {
  35         Some(x) if guard() => (1, x),
  36         None => (3, 3),
  37         Some(y) => (2, y),
  38     };
  39 }
  40
  41 fn main() {
  42     let _ = match Some(1) {
  43         Some(_w) if guard() => 1,
  44         _x => 2,
  45         Some(y) if guard2(y) => 3,
  46         _z => 4,
  47     };
  48 }
  49
  50 // END RUST SOURCE
  51 //
  52 // START rustc.full_tested_match.QualifyAndPromoteConstants.after.mir
  53 //  bb0: {
  54 //      ...
  55 //      _2 = std::option::Option<i32>::Some(const 42i32,);
  56 //      _3 = discriminant(_2);
  57 //      _14 = promoted[1];
  58 //      _4 = &(*_14);
  59 //      _9 = discriminant(_2);
  60 //      switchInt(move _9) -> [0isize: bb5, 1isize: bb3, otherwise: bb7];
  61 //  }
  62 //  bb1: {
  63 //      resume;
  64 //  }
  65 //  bb2: {  // arm1
  66 //      _1 = (const 3i32, const 3i32);
  67 //      goto -> bb13;
  68 //  }
  69 //  bb3: { // binding3(empty) and arm3
  70 //      ReadForMatch(_4);
  71 //      falseEdges -> [real: bb8, imaginary: bb4]; //pre_binding1
  72 //  }
  73 //  bb4: {
  74 //      ReadForMatch(_4);
  75 //      falseEdges -> [real: bb12, imaginary: bb5]; //pre_binding2
  76 //  }
  77 //  bb5: {
  78 //      ReadForMatch(_4);
  79 //      falseEdges -> [real: bb2, imaginary: bb6]; //pre_binding3
  80 //  }
  81 //  bb6: {
  82 //      unreachable;
  83 //  }
  84 //  bb7: {
  85 //      unreachable;
  86 //  }
  87 //  bb8: { // binding1 and guard
  88 //      StorageLive(_7);
  89 //      _13 = promoted[0];
  90 //      _7 = &(((*_13) as Some).0: i32);
  91 //      StorageLive(_10);
  92 //      _10 = const guard() -> [return: bb9, unwind: bb1];
  93 //  }
  94 //  bb9: {
  95 //      switchInt(move _10) -> [false: bb10, otherwise: bb11];
  96 //  }
  97 //  bb10: { // to pre_binding2
  98 //      falseEdges -> [real: bb4, imaginary: bb4];
  99 //  }
 100 //  bb11: { // bindingNoLandingPads.before.mir2 and arm2
 101 //      StorageLive(_5);
 102 //      _5 = ((_2 as Some).0: i32);
 103 //      StorageLive(_11);
 104 //      _11 = _5;
 105 //      _1 = (const 1i32, move _11);
 106 //      StorageDead(_11);
 107 //      goto -> bb13;
 108 //  }
 109 //  bb12: {
 110 //      StorageLive(_8);
 111 //      _8 = ((_2 as Some).0: i32);
 112 //      StorageLive(_12);
 113 //      _12 = _8;
 114 //      _1 = (const 2i32, move_12);
 115 //      StorageDead(_12);
 116 //      goto -> bb13;
 117 //  }
 118 //  bb13: {
 119 //      ...
 120 //      return;
 121 //  }
 122 // END rustc.full_tested_match.QualifyAndPromoteConstants.after.mir
 123 //
 124 // START rustc.full_tested_match2.QualifyAndPromoteConstants.before.mir
 125 //  bb0: {
 126 //      ...
 127 //      _2 = std::option::Option<i32>::Some(const 42i32,);
 128 //      _3 = discriminant(_2);
 129 //      _4 = &_2;
 130 //      _9 = discriminant(_2);
 131 //      switchInt(move _9) -> [0isize: bb4, 1isize: bb3, otherwise: bb7];
 132 //  }
 133 //  bb1: {
 134 //      resume;
 135 //  }
 136 //  bb2: { // arm2
 137 //      _1 = (const 3i32, const 3i32);
 138 //      goto -> bb13;
 139 //  }
 140 //  bb3: {
 141 //      ReadForMatch(_4);
 142 //      falseEdges -> [real: bb8, imaginary: bb4]; //pre_binding1
 143 //  }
 144 //  bb4: {
 145 //      ReadForMatch(_4);
 146 //      falseEdges -> [real: bb2, imaginary: bb5]; //pre_binding2
 147 //  }
 148 //  bb5: {
 149 //      ReadForMatch(_4);
 150 //      falseEdges -> [real: bb12, imaginary: bb6]; //pre_binding3
 151 //  }
 152 //  bb6: {
 153 //      unreachable;
 154 //  }
 155 //  bb7: {
 156 //      unreachable;
 157 //  }
 158 //  bb8: { // binding1 and guard
 159 //      StorageLive(_7);
 160 //      _7 = &((_2 as Some).0: i32);
 161 //      StorageLive(_10);
 162 //      _10 = const guard() -> [return: bb9, unwind: bb1];
 163 //  }
 164 //  bb9: { // end of guard
 165 //      switchInt(move _10) -> [false: bb10, otherwise: bb11];
 166 //  }
 167 //  bb10: { // to pre_binding3 (can skip 2 since this is `Some`)
 168 //      falseEdges -> [real: bb5, imaginary: bb4];
 169 //  }
 170 //  bb11: { // arm1
 171 //      StorageLive(_5);
 172 //      _5 = ((_2 as Some).0: i32);
 173 //      StorageLive(_11);
 174 //      _11 = _5;
 175 //      _1 = (const 1i32, move _11);
 176 //      StorageDead(_11);
 177 //      goto -> bb13;
 178 //  }
 179 //  bb12: { // binding3 and arm3
 180 //      StorageLive(_8);
 181 //      _8 = ((_2 as Some).0: i32);
 182 //      StorageLive(_12);
 183 //      _12 = _8;
 184 //      _1 = (const 2i32, move _12);
 185 //      StorageDead(_12);
 186 //      goto -> bb13;
 187 //  }
 188 //  bb13: {
 189 //      ...
 190 //      return;
 191 //  }
 192 // END rustc.full_tested_match2.QualifyAndPromoteConstants.before.mir
 193 //
 194 // START rustc.main.QualifyAndPromoteConstants.before.mir
 195 // bb0: {
 196 //     ...
 197 //     _2 = std::option::Option<i32>::Some(const 1i32,);
 198 //     _3 = discriminant(_2);
 199 //     _4 = &_2;
 200 //     _13 = discriminant(_2);
 201 //     switchInt(move _13) -> [1isize: bb2, otherwise: bb3];
 202 // }
 203 // bb1: {
 204 //     resume;
 205 // }
 206 // bb2: {
 207 //     ReadForMatch(_4);
 208 //     falseEdges -> [real: bb7, imaginary: bb3]; //pre_binding1
 209 // }
 210 // bb3: {
 211 //     ReadForMatch(_4);
 212 //     falseEdges -> [real: bb11, imaginary: bb4]; //pre_binding2
 213 // }
 214 // bb4: {
 215 //     ReadForMatch(_4);
 216 //     falseEdges -> [real: bb12, imaginary: bb5]; //pre_binding3
 217 // }
 218 // bb5: {
 219 //     ReadForMatch(_4);
 220 //     falseEdges -> [real: bb16, imaginary: bb6]; //pre_binding4
 221 // }
 222 // bb6: {
 223 //     unreachable;
 224 // }
 225 // bb7: { // binding1: Some(w) if guard()
 226 //     StorageLive(_7);
 227 //     _7 = &((_2 as Some).0: i32);
 228 //     StorageLive(_14);
 229 //     _14 = const guard() -> [return: bb8, unwind: bb1];
 230 // }
 231 // bb8: { //end of guard
 232 //     switchInt(move _14) -> [false: bb9, otherwise: bb10];
 233 // }
 234 // bb9: { // to pre_binding2
 235 //     falseEdges -> [real: bb3, imaginary: bb3];
 236 // }
 237 // bb10: { // set up bindings for arm1
 238 //     StorageLive(_5);
 239 //     _5 = ((_2 as Some).0: i32);
 240 //     _1 = const 1i32;
 241 //     goto -> bb17;
 242 // }
 243 // bb11: { // binding2 & arm2
 244 //     StorageLive(_8);
 245 //     _8 = _2;
 246 //     _1 = const 2i32;
 247 //     goto -> bb17;
 248 // }
 249 // bb12: { // binding3: Some(y) if guard2(y)
 250 //     StorageLive(_11);
 251 //     _11 = &((_2 as Some).0: i32);
 252 //     StorageLive(_16);
 253 //     StorageLive(_17);
 254 //     _17 = (*_11);
 255 //     _16 = const guard2(move _17) -> [return: bb13, unwind: bb1];
 256 // }
 257 // bb13: { // end of guard2
 258 //     StorageDead(_17);
 259 //     switchInt(move _16) -> [false: bb14, otherwise: bb15];
 260 // }
 261 // bb14: { // to pre_binding4
 262 //     falseEdges -> [real: bb5, imaginary: bb5];
 263 // }
 264 // bb15: { // set up bindings for arm3
 265 //     StorageLive(_9);
 266 //     _9 = ((_2 as Some).0: i32);
 267 //     _1 = const 3i32;
 268 //     goto -> bb17;
 269 // }
 270 // bb16: { // binding4 & arm4
 271 //     StorageLive(_12);
 272 //     _12 = _2;
 273 //     _1 = const 4i32;
 274 //     goto -> bb17;
 275 // }
 276 // bb17: {
 277 //     ...
 278 //     return;
 279 // }
 280 // END rustc.main.QualifyAndPromoteConstants.before.mir