From 631ce68361f27cb590c14213d777e66976ffd68f Mon Sep 17 00:00:00 2001
From: Camille GILLOT <gillot.camille@gmail.com>
Date: Sat, 21 Oct 2023 13:45:25 +0000
Subject: [PATCH] FileCheck uninhabited_enum_branching.

---
 ...ching.byref.UninhabitedEnumBranching.diff} | 18 ++--
 ...discriminant.UninhabitedEnumBranching.diff | 48 +++++++++
 ...after-uninhabited-enum-branching.after.mir | 65 -------------
 tests/mir-opt/uninhabited_enum_branching.rs   | 70 +++++++++++--
 ...hing.simple.UninhabitedEnumBranching.diff} | 38 +-------
 ...after-uninhabited-enum-branching.after.mir | 97 -------------------
 tests/mir-opt/uninhabited_enum_branching2.rs  | 35 -------
 7 files changed, 126 insertions(+), 245 deletions(-)
 rename tests/mir-opt/{uninhabited_enum_branching2.main.UninhabitedEnumBranching.diff => uninhabited_enum_branching.byref.UninhabitedEnumBranching.diff} (87%)
 create mode 100644 tests/mir-opt/uninhabited_enum_branching.custom_discriminant.UninhabitedEnumBranching.diff
 delete mode 100644 tests/mir-opt/uninhabited_enum_branching.main.SimplifyCfg-after-uninhabited-enum-branching.after.mir
 rename tests/mir-opt/{uninhabited_enum_branching.main.UninhabitedEnumBranching.diff => uninhabited_enum_branching.simple.UninhabitedEnumBranching.diff} (52%)
 delete mode 100644 tests/mir-opt/uninhabited_enum_branching2.main.SimplifyCfg-after-uninhabited-enum-branching.after.mir
 delete mode 100644 tests/mir-opt/uninhabited_enum_branching2.rs

diff --git a/tests/mir-opt/uninhabited_enum_branching2.main.UninhabitedEnumBranching.diff b/tests/mir-opt/uninhabited_enum_branching.byref.UninhabitedEnumBranching.diff
similarity index 87%
rename from tests/mir-opt/uninhabited_enum_branching2.main.UninhabitedEnumBranching.diff
rename to tests/mir-opt/uninhabited_enum_branching.byref.UninhabitedEnumBranching.diff
index 165421acd6916..7919450cdc52a 100644
--- a/tests/mir-opt/uninhabited_enum_branching2.main.UninhabitedEnumBranching.diff
+++ b/tests/mir-opt/uninhabited_enum_branching.byref.UninhabitedEnumBranching.diff
@@ -1,12 +1,12 @@
-- // MIR for `main` before UninhabitedEnumBranching
-+ // MIR for `main` after UninhabitedEnumBranching
+- // MIR for `byref` before UninhabitedEnumBranching
++ // MIR for `byref` after UninhabitedEnumBranching
   
-  fn main() -> () {
+  fn byref() -> () {
       let mut _0: ();
       let _1: Plop;
-      let mut _2: Test1;
+      let mut _2: Test3;
       let _3: &str;
-      let mut _4: &Test1;
+      let mut _4: &Test3;
       let mut _5: isize;
       let _6: &str;
       let _7: &str;
@@ -23,12 +23,12 @@
       bb0: {
           StorageLive(_1);
           StorageLive(_2);
-          _2 = Test1::C;
-          _1 = Plop { xx: const 51_u32, test1: move _2 };
+          _2 = Test3::C;
+          _1 = Plop { xx: const 51_u32, test3: move _2 };
           StorageDead(_2);
           StorageLive(_3);
           StorageLive(_4);
-          _4 = &(_1.1: Test1);
+          _4 = &(_1.1: Test3);
           _5 = discriminant((*_4));
 -         switchInt(move _5) -> [0: bb3, 1: bb4, 2: bb5, 3: bb1, otherwise: bb2];
 +         switchInt(move _5) -> [0: bb12, 1: bb12, 2: bb5, 3: bb1, otherwise: bb12];
@@ -71,7 +71,7 @@
           StorageDead(_4);
           StorageDead(_3);
           StorageLive(_9);
-          _10 = discriminant((_1.1: Test1));
+          _10 = discriminant((_1.1: Test3));
 -         switchInt(move _10) -> [0: bb8, 1: bb9, 2: bb10, 3: bb7, otherwise: bb2];
 +         switchInt(move _10) -> [0: bb12, 1: bb12, 2: bb10, 3: bb7, otherwise: bb12];
       }
diff --git a/tests/mir-opt/uninhabited_enum_branching.custom_discriminant.UninhabitedEnumBranching.diff b/tests/mir-opt/uninhabited_enum_branching.custom_discriminant.UninhabitedEnumBranching.diff
new file mode 100644
index 0000000000000..5e15298a78c12
--- /dev/null
+++ b/tests/mir-opt/uninhabited_enum_branching.custom_discriminant.UninhabitedEnumBranching.diff
@@ -0,0 +1,48 @@
+- // MIR for `custom_discriminant` before UninhabitedEnumBranching
++ // MIR for `custom_discriminant` after UninhabitedEnumBranching
+  
+  fn custom_discriminant() -> () {
+      let mut _0: ();
+      let _1: &str;
+      let mut _2: Test2;
+      let mut _3: isize;
+      let _4: &str;
+  
+      bb0: {
+          StorageLive(_1);
+          StorageLive(_2);
+          _2 = Test2::D;
+          _3 = discriminant(_2);
+-         switchInt(move _3) -> [4: bb3, 5: bb1, otherwise: bb2];
++         switchInt(move _3) -> [4: bb3, 5: bb1, otherwise: bb5];
+      }
+  
+      bb1: {
+          StorageLive(_4);
+          _4 = const "E";
+          _1 = &(*_4);
+          StorageDead(_4);
+          goto -> bb4;
+      }
+  
+      bb2: {
+          unreachable;
+      }
+  
+      bb3: {
+          _1 = const "D";
+          goto -> bb4;
+      }
+  
+      bb4: {
+          StorageDead(_2);
+          StorageDead(_1);
+          _0 = const ();
+          return;
++     }
++ 
++     bb5: {
++         unreachable;
+      }
+  }
+  
diff --git a/tests/mir-opt/uninhabited_enum_branching.main.SimplifyCfg-after-uninhabited-enum-branching.after.mir b/tests/mir-opt/uninhabited_enum_branching.main.SimplifyCfg-after-uninhabited-enum-branching.after.mir
deleted file mode 100644
index 1df3b74b3e7d9..0000000000000
--- a/tests/mir-opt/uninhabited_enum_branching.main.SimplifyCfg-after-uninhabited-enum-branching.after.mir
+++ /dev/null
@@ -1,65 +0,0 @@
-// MIR for `main` after SimplifyCfg-after-uninhabited-enum-branching
-
-fn main() -> () {
-    let mut _0: ();
-    let _1: &str;
-    let mut _2: Test1;
-    let mut _3: isize;
-    let _4: &str;
-    let _5: &str;
-    let _6: &str;
-    let mut _7: Test2;
-    let mut _8: isize;
-    let _9: &str;
-    let mut _10: bool;
-    let mut _11: bool;
-    let mut _12: bool;
-
-    bb0: {
-        StorageLive(_1);
-        StorageLive(_2);
-        _2 = Test1::C;
-        _3 = discriminant(_2);
-        _10 = Ne(_3, const 0_isize);
-        assume(move _10);
-        _11 = Ne(_3, const 1_isize);
-        assume(move _11);
-        _12 = Eq(_3, const 2_isize);
-        assume(move _12);
-        StorageLive(_5);
-        _5 = const "C";
-        _1 = &(*_5);
-        StorageDead(_5);
-        StorageDead(_2);
-        StorageDead(_1);
-        StorageLive(_6);
-        StorageLive(_7);
-        _7 = Test2::D;
-        _8 = discriminant(_7);
-        switchInt(move _8) -> [4: bb3, 5: bb2, otherwise: bb1];
-    }
-
-    bb1: {
-        unreachable;
-    }
-
-    bb2: {
-        StorageLive(_9);
-        _9 = const "E";
-        _6 = &(*_9);
-        StorageDead(_9);
-        goto -> bb4;
-    }
-
-    bb3: {
-        _6 = const "D";
-        goto -> bb4;
-    }
-
-    bb4: {
-        StorageDead(_7);
-        StorageDead(_6);
-        _0 = const ();
-        return;
-    }
-}
diff --git a/tests/mir-opt/uninhabited_enum_branching.rs b/tests/mir-opt/uninhabited_enum_branching.rs
index 96ae84eca5093..60389117b1614 100644
--- a/tests/mir-opt/uninhabited_enum_branching.rs
+++ b/tests/mir-opt/uninhabited_enum_branching.rs
@@ -1,11 +1,11 @@
-// skip-filecheck
-enum Empty { }
+// unit-test: UninhabitedEnumBranching
+enum Empty {}
 
 // test matching an enum with uninhabited variants
 enum Test1 {
     A(Empty),
     B(Empty),
-    C
+    C,
 }
 
 // test an enum where the discriminants don't match the variant indexes
@@ -15,17 +15,75 @@ enum Test2 {
     E = 5,
 }
 
-// EMIT_MIR uninhabited_enum_branching.main.UninhabitedEnumBranching.diff
-// EMIT_MIR uninhabited_enum_branching.main.SimplifyCfg-after-uninhabited-enum-branching.after.mir
-fn main() {
+// test matching an enum with uninhabited variants and multiple inhabited
+enum Test3 {
+    A(Empty),
+    B(Empty),
+    C,
+    D,
+}
+
+struct Plop {
+    xx: u32,
+    test3: Test3,
+}
+
+// EMIT_MIR uninhabited_enum_branching.simple.UninhabitedEnumBranching.diff
+fn simple() {
+    // CHECK-LABEL: fn simple(
+    // CHECK: [[discr:_.*]] = discriminant(
+    // CHECK: switchInt(move [[discr]]) -> [0: [[unreachable:bb.*]], 1: [[unreachable]], 2: bb1, otherwise: [[unreachable]]];
+    // CHECK: [[unreachable]]: {
+    // CHECK-NEXT: unreachable;
     match Test1::C {
         Test1::A(_) => "A(Empty)",
         Test1::B(_) => "B(Empty)",
         Test1::C => "C",
     };
+}
 
+// EMIT_MIR uninhabited_enum_branching.custom_discriminant.UninhabitedEnumBranching.diff
+fn custom_discriminant() {
+    // CHECK-LABEL: fn custom_discriminant(
+    // CHECK: [[discr:_.*]] = discriminant(
+    // CHECK: switchInt(move [[discr]]) -> [4: bb3, 5: bb1, otherwise: bb5];
+    // CHECK: bb5: {
+    // CHECK-NEXT: unreachable;
     match Test2::D {
         Test2::D => "D",
         Test2::E => "E",
     };
 }
+
+// EMIT_MIR uninhabited_enum_branching.byref.UninhabitedEnumBranching.diff
+fn byref() {
+    // CHECK-LABEL: fn byref(
+    let plop = Plop { xx: 51, test3: Test3::C };
+
+    // CHECK: [[ref_discr:_.*]] = discriminant((*
+    // CHECK: switchInt(move [[ref_discr]]) -> [0: [[unreachable:bb.*]], 1: [[unreachable]], 2: bb5, 3: bb1, otherwise: [[unreachable]]];
+    match &plop.test3 {
+        Test3::A(_) => "A(Empty)",
+        Test3::B(_) => "B(Empty)",
+        Test3::C => "C",
+        Test3::D => "D",
+    };
+
+    // CHECK: [[discr:_.*]] = discriminant(
+    // CHECK: switchInt(move [[discr]]) -> [0: [[unreachable]], 1: [[unreachable]], 2: bb10, 3: bb7, otherwise: [[unreachable]]];
+    match plop.test3 {
+        Test3::A(_) => "A(Empty)",
+        Test3::B(_) => "B(Empty)",
+        Test3::C => "C",
+        Test3::D => "D",
+    };
+
+    // CHECK: [[unreachable]]: {
+    // CHECK-NEXT: unreachable;
+}
+
+fn main() {
+    simple();
+    custom_discriminant();
+    byref();
+}
diff --git a/tests/mir-opt/uninhabited_enum_branching.main.UninhabitedEnumBranching.diff b/tests/mir-opt/uninhabited_enum_branching.simple.UninhabitedEnumBranching.diff
similarity index 52%
rename from tests/mir-opt/uninhabited_enum_branching.main.UninhabitedEnumBranching.diff
rename to tests/mir-opt/uninhabited_enum_branching.simple.UninhabitedEnumBranching.diff
index 5b107f80ce80b..410db79802edc 100644
--- a/tests/mir-opt/uninhabited_enum_branching.main.UninhabitedEnumBranching.diff
+++ b/tests/mir-opt/uninhabited_enum_branching.simple.UninhabitedEnumBranching.diff
@@ -1,17 +1,13 @@
-- // MIR for `main` before UninhabitedEnumBranching
-+ // MIR for `main` after UninhabitedEnumBranching
+- // MIR for `simple` before UninhabitedEnumBranching
++ // MIR for `simple` after UninhabitedEnumBranching
   
-  fn main() -> () {
+  fn simple() -> () {
       let mut _0: ();
       let _1: &str;
       let mut _2: Test1;
       let mut _3: isize;
       let _4: &str;
       let _5: &str;
-      let _6: &str;
-      let mut _7: Test2;
-      let mut _8: isize;
-      let _9: &str;
   
       bb0: {
           StorageLive(_1);
@@ -19,7 +15,7 @@
           _2 = Test1::C;
           _3 = discriminant(_2);
 -         switchInt(move _3) -> [0: bb3, 1: bb4, 2: bb1, otherwise: bb2];
-+         switchInt(move _3) -> [0: bb9, 1: bb9, 2: bb1, otherwise: bb9];
++         switchInt(move _3) -> [0: bb6, 1: bb6, 2: bb1, otherwise: bb6];
       }
   
       bb1: {
@@ -50,35 +46,11 @@
       bb5: {
           StorageDead(_2);
           StorageDead(_1);
-          StorageLive(_6);
-          StorageLive(_7);
-          _7 = Test2::D;
-          _8 = discriminant(_7);
--         switchInt(move _8) -> [4: bb7, 5: bb6, otherwise: bb2];
-+         switchInt(move _8) -> [4: bb7, 5: bb6, otherwise: bb9];
-      }
-  
-      bb6: {
-          StorageLive(_9);
-          _9 = const "E";
-          _6 = &(*_9);
-          StorageDead(_9);
-          goto -> bb8;
-      }
-  
-      bb7: {
-          _6 = const "D";
-          goto -> bb8;
-      }
-  
-      bb8: {
-          StorageDead(_7);
-          StorageDead(_6);
           _0 = const ();
           return;
 +     }
 + 
-+     bb9: {
++     bb6: {
 +         unreachable;
       }
   }
diff --git a/tests/mir-opt/uninhabited_enum_branching2.main.SimplifyCfg-after-uninhabited-enum-branching.after.mir b/tests/mir-opt/uninhabited_enum_branching2.main.SimplifyCfg-after-uninhabited-enum-branching.after.mir
deleted file mode 100644
index 06375b3ffaebf..0000000000000
--- a/tests/mir-opt/uninhabited_enum_branching2.main.SimplifyCfg-after-uninhabited-enum-branching.after.mir
+++ /dev/null
@@ -1,97 +0,0 @@
-// MIR for `main` after SimplifyCfg-after-uninhabited-enum-branching
-
-fn main() -> () {
-    let mut _0: ();
-    let _1: Plop;
-    let mut _2: Test1;
-    let _3: &str;
-    let mut _4: &Test1;
-    let mut _5: isize;
-    let _6: &str;
-    let _7: &str;
-    let _8: &str;
-    let _9: &str;
-    let mut _10: isize;
-    let _11: &str;
-    let _12: &str;
-    let _13: &str;
-    let mut _14: bool;
-    let mut _15: bool;
-    let mut _16: bool;
-    let mut _17: bool;
-    scope 1 {
-        debug plop => _1;
-    }
-
-    bb0: {
-        StorageLive(_1);
-        StorageLive(_2);
-        _2 = Test1::C;
-        _1 = Plop { xx: const 51_u32, test1: move _2 };
-        StorageDead(_2);
-        StorageLive(_3);
-        StorageLive(_4);
-        _4 = &(_1.1: Test1);
-        _5 = discriminant((*_4));
-        _16 = Ne(_5, const 0_isize);
-        assume(move _16);
-        _17 = Ne(_5, const 1_isize);
-        assume(move _17);
-        switchInt(move _5) -> [2: bb3, 3: bb1, otherwise: bb2];
-    }
-
-    bb1: {
-        StorageLive(_8);
-        _8 = const "D";
-        _3 = &(*_8);
-        StorageDead(_8);
-        goto -> bb4;
-    }
-
-    bb2: {
-        unreachable;
-    }
-
-    bb3: {
-        StorageLive(_7);
-        _7 = const "C";
-        _3 = &(*_7);
-        StorageDead(_7);
-        goto -> bb4;
-    }
-
-    bb4: {
-        StorageDead(_4);
-        StorageDead(_3);
-        StorageLive(_9);
-        _10 = discriminant((_1.1: Test1));
-        _14 = Ne(_10, const 0_isize);
-        assume(move _14);
-        _15 = Ne(_10, const 1_isize);
-        assume(move _15);
-        switchInt(move _10) -> [2: bb6, 3: bb5, otherwise: bb2];
-    }
-
-    bb5: {
-        StorageLive(_13);
-        _13 = const "D";
-        _9 = &(*_13);
-        StorageDead(_13);
-        goto -> bb7;
-    }
-
-    bb6: {
-        StorageLive(_12);
-        _12 = const "C";
-        _9 = &(*_12);
-        StorageDead(_12);
-        goto -> bb7;
-    }
-
-    bb7: {
-        StorageDead(_9);
-        _0 = const ();
-        StorageDead(_1);
-        return;
-    }
-}
diff --git a/tests/mir-opt/uninhabited_enum_branching2.rs b/tests/mir-opt/uninhabited_enum_branching2.rs
deleted file mode 100644
index 751f2ae01f8ba..0000000000000
--- a/tests/mir-opt/uninhabited_enum_branching2.rs
+++ /dev/null
@@ -1,35 +0,0 @@
-// skip-filecheck
-enum Empty { }
-
-// test matching an enum with uninhabited variants
-enum Test1 {
-    A(Empty),
-    B(Empty),
-    C,
-    D,
-}
-
-struct Plop {
-    xx: u32,
-    test1: Test1,
-}
-
-// EMIT_MIR uninhabited_enum_branching2.main.UninhabitedEnumBranching.diff
-// EMIT_MIR uninhabited_enum_branching2.main.SimplifyCfg-after-uninhabited-enum-branching.after.mir
-fn main() {
-    let plop = Plop { xx: 51, test1: Test1::C };
-
-    match &plop.test1 {
-        Test1::A(_) => "A(Empty)",
-        Test1::B(_) => "B(Empty)",
-        Test1::C => "C",
-        Test1::D => "D",
-    };
-
-    match plop.test1 {
-        Test1::A(_) => "A(Empty)",
-        Test1::B(_) => "B(Empty)",
-        Test1::C => "C",
-        Test1::D => "D",
-    };
-}