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 //      _4 = &(promoted[1]: std::option::Option<i32>);
  58 //      _9 = discriminant(_2);
  59 //      switchInt(move _9) -> [0isize: bb5, 1isize: bb3, otherwise: bb7];
  60 //  }
  61 //  bb1: {
  62 //      resume;
  63 //  }
  64 //  bb2: {  // arm1
  65 //      _1 = (const 3i32, const 3i32);
  66 //      goto -> bb13;
  67 //  }
  68 //  bb3: { // binding3(empty) and arm3
  69 //      ReadForMatch(_4);
  70 //      falseEdges -> [real: bb8, imaginary: bb4]; //pre_binding1
  71 //  }
  72 //  bb4: {
  73 //      ReadForMatch(_4);
  74 //      falseEdges -> [real: bb12, imaginary: bb5]; //pre_binding2
  75 //  }
  76 //  bb5: {
  77 //      ReadForMatch(_4);
  78 //      falseEdges -> [real: bb2, imaginary: bb6]; //pre_binding3
  79 //  }
  80 //  bb6: {
  81 //      unreachable;
  82 //  }
  83 //  bb7: {
  84 //      unreachable;
  85 //  }
  86 //  bb8: { // binding1 and guard
  87 //      StorageLive(_7);
  88 //      _7 = &(((promoted[0]: std::option::Option<i32>) as Some).0: i32);
  89 //      StorageLive(_10);
  90 //      _10 = const guard() -> [return: bb9, unwind: bb1];
  91 //  }
  92 //  bb9: {
  93 //      switchInt(move _10) -> [false: bb10, otherwise: bb11];
  94 //  }
  95 //  bb10: { // to pre_binding2
  96 //      falseEdges -> [real: bb4, imaginary: bb4];
  97 //  }
  98 //  bb11: { // bindingNoLandingPads.before.mir2 and arm2
  99 //      StorageLive(_5);
 100 //      _5 = ((_2 as Some).0: i32);
 101 //      StorageLive(_11);
 102 //      _11 = _5;
 103 //      _1 = (const 1i32, move _11);
 104 //      StorageDead(_11);
 105 //      goto -> bb13;
 106 //  }
 107 //  bb12: {
 108 //      StorageLive(_8);
 109 //      _8 = ((_2 as Some).0: i32);
 110 //      StorageLive(_12);
 111 //      _12 = _8;
 112 //      _1 = (const 2i32, move_12);
 113 //      StorageDead(_12);
 114 //      goto -> bb13;
 115 //  }
 116 //  bb13: {
 117 //      ...
 118 //      return;
 119 //  }
 120 // END rustc.full_tested_match.QualifyAndPromoteConstants.after.mir
 121 //
 122 // START rustc.full_tested_match2.QualifyAndPromoteConstants.before.mir
 123 //  bb0: {
 124 //      ...
 125 //      _2 = std::option::Option<i32>::Some(const 42i32,);
 126 //      _3 = discriminant(_2);
 127 //      _4 = &_2;
 128 //      _9 = discriminant(_2);
 129 //      switchInt(move _9) -> [0isize: bb4, 1isize: bb3, otherwise: bb7];
 130 //  }
 131 //  bb1: {
 132 //      resume;
 133 //  }
 134 //  bb2: { // arm2
 135 //      _1 = (const 3i32, const 3i32);
 136 //      goto -> bb13;
 137 //  }
 138 //  bb3: {
 139 //      ReadForMatch(_4);
 140 //      falseEdges -> [real: bb8, imaginary: bb4]; //pre_binding1
 141 //  }
 142 //  bb4: {
 143 //      ReadForMatch(_4);
 144 //      falseEdges -> [real: bb2, imaginary: bb5]; //pre_binding2
 145 //  }
 146 //  bb5: {
 147 //      ReadForMatch(_4);
 148 //      falseEdges -> [real: bb12, imaginary: bb6]; //pre_binding3
 149 //  }
 150 //  bb6: {
 151 //      unreachable;
 152 //  }
 153 //  bb7: {
 154 //      unreachable;
 155 //  }
 156 //  bb8: { // binding1 and guard
 157 //      StorageLive(_7);
 158 //      _7 = &((_2 as Some).0: i32);
 159 //      StorageLive(_10);
 160 //      _10 = const guard() -> [return: bb9, unwind: bb1];
 161 //  }
 162 //  bb9: { // end of guard
 163 //      switchInt(move _10) -> [false: bb10, otherwise: bb11];
 164 //  }
 165 //  bb10: { // to pre_binding3 (can skip 2 since this is `Some`)
 166 //      falseEdges -> [real: bb5, imaginary: bb4];
 167 //  }
 168 //  bb11: { // arm1
 169 //      StorageLive(_5);
 170 //      _5 = ((_2 as Some).0: i32);
 171 //      StorageLive(_11);
 172 //      _11 = _5;
 173 //      _1 = (const 1i32, move _11);
 174 //      StorageDead(_11);
 175 //      goto -> bb13;
 176 //  }
 177 //  bb12: { // binding3 and arm3
 178 //      StorageLive(_8);
 179 //      _8 = ((_2 as Some).0: i32);
 180 //      StorageLive(_12);
 181 //      _12 = _8;
 182 //      _1 = (const 2i32, move _12);
 183 //      StorageDead(_12);
 184 //      goto -> bb13;
 185 //  }
 186 //  bb13: {
 187 //      ...
 188 //      return;
 189 //  }
 190 // END rustc.full_tested_match2.QualifyAndPromoteConstants.before.mir
 191 //
 192 // START rustc.main.QualifyAndPromoteConstants.before.mir
 193 // bb0: {
 194 //     ...
 195 //     _2 = std::option::Option<i32>::Some(const 1i32,);
 196 //     _3 = discriminant(_2);
 197 //     _4 = &_2;
 198 //     _13 = discriminant(_2);
 199 //     switchInt(move _13) -> [1isize: bb2, otherwise: bb3];
 200 // }
 201 // bb1: {
 202 //     resume;
 203 // }
 204 // bb2: {
 205 //     ReadForMatch(_4);
 206 //     falseEdges -> [real: bb7, imaginary: bb3]; //pre_binding1
 207 // }
 208 // bb3: {
 209 //     ReadForMatch(_4);
 210 //     falseEdges -> [real: bb11, imaginary: bb4]; //pre_binding2
 211 // }
 212 // bb4: {
 213 //     ReadForMatch(_4);
 214 //     falseEdges -> [real: bb12, imaginary: bb5]; //pre_binding3
 215 // }
 216 // bb5: {
 217 //     ReadForMatch(_4);
 218 //     falseEdges -> [real: bb16, imaginary: bb6]; //pre_binding4
 219 // }
 220 // bb6: {
 221 //     unreachable;
 222 // }
 223 // bb7: { // binding1: Some(w) if guard()
 224 //     StorageLive(_7);
 225 //     _7 = &((_2 as Some).0: i32);
 226 //     StorageLive(_14);
 227 //     _14 = const guard() -> [return: bb8, unwind: bb1];
 228 // }
 229 // bb8: { //end of guard
 230 //     switchInt(move _14) -> [false: bb9, otherwise: bb10];
 231 // }
 232 // bb9: { // to pre_binding2
 233 //     falseEdges -> [real: bb3, imaginary: bb3];
 234 // }
 235 // bb10: { // set up bindings for arm1
 236 //     StorageLive(_5);
 237 //     _5 = ((_2 as Some).0: i32);
 238 //     _1 = const 1i32;
 239 //     goto -> bb17;
 240 // }
 241 // bb11: { // binding2 & arm2
 242 //     StorageLive(_8);
 243 //     _8 = _2;
 244 //     _1 = const 2i32;
 245 //     goto -> bb17;
 246 // }
 247 // bb12: { // binding3: Some(y) if guard2(y)
 248 //     StorageLive(_11);
 249 //     _11 = &((_2 as Some).0: i32);
 250 //     StorageLive(_16);
 251 //     StorageLive(_17);
 252 //     _17 = (*_11);
 253 //     _16 = const guard2(move _17) -> [return: bb13, unwind: bb1];
 254 // }
 255 // bb13: { // end of guard2
 256 //     StorageDead(_17);
 257 //     switchInt(move _16) -> [false: bb14, otherwise: bb15];
 258 // }
 259 // bb14: { // to pre_binding4
 260 //     falseEdges -> [real: bb5, imaginary: bb5];
 261 // }
 262 // bb15: { // set up bindings for arm3
 263 //     StorageLive(_9);
 264 //     _9 = ((_2 as Some).0: i32);
 265 //     _1 = const 3i32;
 266 //     goto -> bb17;
 267 // }
 268 // bb16: { // binding4 & arm4
 269 //     StorageLive(_12);
 270 //     _12 = _2;
 271 //     _1 = const 4i32;
 272 //     goto -> bb17;
 273 // }
 274 // bb17: {
 275 //     ...
 276 //     return;
 277 // }
 278 // END rustc.main.QualifyAndPromoteConstants.before.mir