Adding upstream version 86.0.1.upstream/86.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 35 insertions, 0 deletions

diff --git a/third_party/rust/cranelift-frontend/src/variable.rs b/third_party/rust/cranelift-frontend/src/variable.rs
new file mode 100644
index 0000000000..9a40b9dfe9
--- /dev/null
+++ b/third_party/rust/cranelift-frontend/src/variable.rs
@@ -0,0 +1,35 @@
+//! A basic `Variable` implementation.
+//!
+//! Frontends can use any indexing scheme they see fit and
+//! generate the appropriate `Variable` instances.
+//!
+//! Note: The `Variable` is used by Cranelift to index into densely allocated
+//! arrays containing information about your mutable variables
+//! Thus, make sure that Variable's indexes are allocated contiguously and
+//! starting at `0`.
+
+use core::u32;
+use cranelift_codegen::entity::EntityRef;
+
+///! An opaque reference to a variable.
+#[derive(Copy, Clone, PartialEq, Eq, Debug)]
+pub struct Variable(u32);
+
+impl Variable {
+    /// Create a new Variable with the given index.
+    pub fn with_u32(index: u32) -> Self {
+        debug_assert!(index < u32::MAX);
+        Self(index)
+    }
+}
+
+impl EntityRef for Variable {
+    fn new(index: usize) -> Self {
+        debug_assert!(index < (u32::MAX as usize));
+        Self(index as u32)
+    }
+
+    fn index(self) -> usize {
+        self.0 as usize
+    }
+}