Rollup merge of #105814 - JakobDegen:custom-mir-terms, r=oli-obk

Support call and drop terminators in custom mir

The only caveat with this change is that cleanup blocks are not supported. I would like to add them, but it's not quite clear to me what the best way to do that is, so I'll have to think about it some more.

r? ``@oli-obk``

6 files changed, 180 insertions, 0 deletions

diff --git a/src/test/mir-opt/building/custom/terminators.assert_nonzero.built.after.mir b/src/test/mir-opt/building/custom/terminators.assert_nonzero.built.after.mir
new file mode 100644
index 00000000000..a1a27226b4e
--- /dev/null
+++ b/src/test/mir-opt/building/custom/terminators.assert_nonzero.built.after.mir
@@ -0,0 +1,17 @@
+// MIR for `assert_nonzero` after built
+
+fn assert_nonzero(_1: i32) -> () {
+    let mut _0: ();                      // return place in scope 0 at $DIR/terminators.rs:+0:27: +0:27
+
+    bb0: {
+        switchInt(_1) -> [0: bb1, otherwise: bb2]; // scope 0 at $DIR/terminators.rs:+3:13: +6:14
+    }
+
+    bb1: {
+        unreachable;                     // scope 0 at $DIR/terminators.rs:+10:13: +10:26
+    }
+
+    bb2: {
+        return;                          // scope 0 at $DIR/terminators.rs:+14:13: +14:21
+    }
+}
diff --git a/src/test/mir-opt/building/custom/terminators.direct_call.built.after.mir b/src/test/mir-opt/building/custom/terminators.direct_call.built.after.mir
new file mode 100644
index 00000000000..1b2345a965e
--- /dev/null
+++ b/src/test/mir-opt/building/custom/terminators.direct_call.built.after.mir
@@ -0,0 +1,16 @@
+// MIR for `direct_call` after built
+
+fn direct_call(_1: i32) -> i32 {
+    let mut _0: i32;                     // return place in scope 0 at $DIR/terminators.rs:+0:27: +0:30
+
+    bb0: {
+        _0 = ident::<i32>(_1) -> bb1;    // scope 0 at $DIR/terminators.rs:+3:13: +3:42
+                                         // mir::Constant
+                                         // + span: $DIR/terminators.rs:15:33: 15:38
+                                         // + literal: Const { ty: fn(i32) -> i32 {ident::<i32>}, val: Value(<ZST>) }
+    }
+
+    bb1: {
+        return;                          // scope 0 at $DIR/terminators.rs:+7:13: +7:21
+    }
+}
diff --git a/src/test/mir-opt/building/custom/terminators.drop_first.built.after.mir b/src/test/mir-opt/building/custom/terminators.drop_first.built.after.mir
new file mode 100644
index 00000000000..c903e594696
--- /dev/null
+++ b/src/test/mir-opt/building/custom/terminators.drop_first.built.after.mir
@@ -0,0 +1,13 @@
+// MIR for `drop_first` after built
+
+fn drop_first(_1: WriteOnDrop<'_>, _2: WriteOnDrop<'_>) -> () {
+    let mut _0: ();                      // return place in scope 0 at $DIR/terminators.rs:+0:59: +0:59
+
+    bb0: {
+        replace(_1 <- move _2) -> bb1;   // scope 0 at $DIR/terminators.rs:+3:13: +3:49
+    }
+
+    bb1: {
+        return;                          // scope 0 at $DIR/terminators.rs:+7:13: +7:21
+    }
+}
diff --git a/src/test/mir-opt/building/custom/terminators.drop_second.built.after.mir b/src/test/mir-opt/building/custom/terminators.drop_second.built.after.mir
new file mode 100644
index 00000000000..f14246f2d12
--- /dev/null
+++ b/src/test/mir-opt/building/custom/terminators.drop_second.built.after.mir
@@ -0,0 +1,13 @@
+// MIR for `drop_second` after built
+
+fn drop_second(_1: WriteOnDrop<'_>, _2: WriteOnDrop<'_>) -> () {
+    let mut _0: ();                      // return place in scope 0 at $DIR/terminators.rs:+0:60: +0:60
+
+    bb0: {
+        drop(_2) -> bb1;                 // scope 0 at $DIR/terminators.rs:+3:13: +3:30
+    }
+
+    bb1: {
+        return;                          // scope 0 at $DIR/terminators.rs:+7:13: +7:21
+    }
+}
diff --git a/src/test/mir-opt/building/custom/terminators.indirect_call.built.after.mir b/src/test/mir-opt/building/custom/terminators.indirect_call.built.after.mir
new file mode 100644
index 00000000000..2f1b14069ab
--- /dev/null
+++ b/src/test/mir-opt/building/custom/terminators.indirect_call.built.after.mir
@@ -0,0 +1,13 @@
+// MIR for `indirect_call` after built
+
+fn indirect_call(_1: i32, _2: fn(i32) -> i32) -> i32 {
+    let mut _0: i32;                     // return place in scope 0 at $DIR/terminators.rs:+0:48: +0:51
+
+    bb0: {
+        _0 = _2(_1) -> bb1;              // scope 0 at $DIR/terminators.rs:+3:13: +3:38
+    }
+
+    bb1: {
+        return;                          // scope 0 at $DIR/terminators.rs:+7:13: +7:21
+    }
+}
diff --git a/src/test/mir-opt/building/custom/terminators.rs b/src/test/mir-opt/building/custom/terminators.rs
new file mode 100644
index 00000000000..c23233fcf9a
--- /dev/null
+++ b/src/test/mir-opt/building/custom/terminators.rs
@@ -0,0 +1,108 @@
+#![feature(custom_mir, core_intrinsics)]
+
+extern crate core;
+use core::intrinsics::mir::*;
+
+fn ident<T>(t: T) -> T {
+    t
+}
+
+// EMIT_MIR terminators.direct_call.built.after.mir
+#[custom_mir(dialect = "built")]
+fn direct_call(x: i32) -> i32 {
+    mir!(
+        {
+            Call(RET, retblock, ident(x))
+        }
+
+        retblock = {
+            Return()
+        }
+    )
+}
+
+// EMIT_MIR terminators.indirect_call.built.after.mir
+#[custom_mir(dialect = "built")]
+fn indirect_call(x: i32, f: fn(i32) -> i32) -> i32 {
+    mir!(
+        {
+            Call(RET, retblock, f(x))
+        }
+
+        retblock = {
+            Return()
+        }
+    )
+}
+
+struct WriteOnDrop<'a>(&'a mut i32, i32);
+
+impl<'a> Drop for WriteOnDrop<'a> {
+    fn drop(&mut self) {
+        *self.0 = self.1;
+    }
+}
+
+// EMIT_MIR terminators.drop_first.built.after.mir
+#[custom_mir(dialect = "built")]
+fn drop_first<'a>(a: WriteOnDrop<'a>, b: WriteOnDrop<'a>) {
+    mir!(
+        {
+            DropAndReplace(a, Move(b), retblock)
+        }
+
+        retblock = {
+            Return()
+        }
+    )
+}
+
+// EMIT_MIR terminators.drop_second.built.after.mir
+#[custom_mir(dialect = "built")]
+fn drop_second<'a>(a: WriteOnDrop<'a>, b: WriteOnDrop<'a>) {
+    mir!(
+        {
+            Drop(b, retblock)
+        }
+
+        retblock = {
+            Return()
+        }
+    )
+}
+
+// EMIT_MIR terminators.assert_nonzero.built.after.mir
+#[custom_mir(dialect = "built")]
+fn assert_nonzero(a: i32) {
+    mir!(
+        {
+            match a {
+                0 => unreachable,
+                _ => retblock
+            }
+        }
+
+        unreachable = {
+            Unreachable()
+        }
+
+        retblock = {
+            Return()
+        }
+    )
+}
+
+fn main() {
+    assert_eq!(direct_call(5), 5);
+    assert_eq!(indirect_call(5, ident), 5);
+
+    let mut a = 0;
+    let mut b = 0;
+    drop_first(WriteOnDrop(&mut a, 1), WriteOnDrop(&mut b, 1));
+    assert_eq!((a, b), (1, 0));
+
+    let mut a = 0;
+    let mut b = 0;
+    drop_second(WriteOnDrop(&mut a, 1), WriteOnDrop(&mut b, 1));
+    assert_eq!((a, b), (0, 1));
+}