From ab8a947fa0e8f8397ad9c831741e6429fbed2c0b Mon Sep 17 00:00:00 2001
From: Nicholas Nethercote <nnethercote@mozilla.com>
Date: Fri, 9 Nov 2018 09:57:02 +1100
Subject: [PATCH 1/4] Move `static_assert!` into librustc_data_structures.
This means it can be used by more crates.
---
src/librustc/macros.rs | 10 ----------
src/librustc_data_structures/lib.rs | 1 +
src/librustc_data_structures/macros.rs | 21 +++++++++++++++++++++
3 files changed, 22 insertions(+), 10 deletions(-)
create mode 100644 src/librustc_data_structures/macros.rs
diff --git a/src/librustc/macros.rs b/src/librustc/macros.rs
index f21f949c9f5..781a0fa3f66 100644
--- a/src/librustc/macros.rs
+++ b/src/librustc/macros.rs
@@ -62,16 +62,6 @@ macro_rules! span_bug {
})
}
-#[macro_export]
-macro_rules! static_assert {
- ($name:ident: $test:expr) => {
- // Use the bool to access an array such that if the bool is false, the access
- // is out-of-bounds.
- #[allow(dead_code)]
- static $name: () = [()][!$test as usize];
- }
-}
-
#[macro_export]
macro_rules! __impl_stable_hash_field {
($field:ident, $ctx:expr, $hasher:expr) => ($field.hash_stable($ctx, $hasher));
diff --git a/src/librustc_data_structures/lib.rs b/src/librustc_data_structures/lib.rs
index 07e5548216f..135abebdacb 100644
--- a/src/librustc_data_structures/lib.rs
+++ b/src/librustc_data_structures/lib.rs
@@ -57,6 +57,7 @@ extern crate rustc_cratesio_shim;
pub use rustc_serialize::hex::ToHex;
+pub mod macros;
pub mod svh;
pub mod base_n;
pub mod bit_set;
diff --git a/src/librustc_data_structures/macros.rs b/src/librustc_data_structures/macros.rs
new file mode 100644
index 00000000000..3cc91b0e93f
--- /dev/null
+++ b/src/librustc_data_structures/macros.rs
@@ -0,0 +1,21 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+/// A simple static assertion macro. The first argument should be a unique
+/// ALL_CAPS identifier that describes the condition.
+#[macro_export]
+macro_rules! static_assert {
+ ($name:ident: $test:expr) => {
+ // Use the bool to access an array such that if the bool is false, the access
+ // is out-of-bounds.
+ #[allow(dead_code)]
+ static $name: () = [()][!$test as usize];
+ }
+}
From 49f482f5372c247dc50c1a2159a1ba5ee3cf5f15 Mon Sep 17 00:00:00 2001
From: Nicholas Nethercote <nnethercote@mozilla.com>
Date: Fri, 9 Nov 2018 10:19:51 +1100
Subject: [PATCH 2/4] Move a `static_assert!` to a better spot.
And make it x86_64-only so it can use `==` instead of `<=`.
---
src/librustc/mir/mod.rs | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/src/librustc/mir/mod.rs b/src/librustc/mir/mod.rs
index 8a32e8f46c2..46b61d8ffe6 100644
--- a/src/librustc/mir/mod.rs
+++ b/src/librustc/mir/mod.rs
@@ -1719,14 +1719,14 @@ pub struct Statement<'tcx> {
pub kind: StatementKind<'tcx>,
}
+// `Statement` is used a lot. Make sure it doesn't unintentionally get bigger.
+#[cfg(target_arch = "x86_64")]
+static_assert!(MEM_SIZE_OF_STATEMENT: mem::size_of::<Statement<'_>>() == 56);
+
impl<'tcx> Statement<'tcx> {
/// Changes a statement to a nop. This is both faster than deleting instructions and avoids
/// invalidating statement indices in `Location`s.
pub fn make_nop(&mut self) {
- // `Statement` contributes significantly to peak memory usage. Make
- // sure it doesn't get bigger.
- static_assert!(STATEMENT_IS_AT_MOST_56_BYTES: mem::size_of::<Statement<'_>>() <= 56);
-
self.kind = StatementKind::Nop
}
From fb3dd9f64ee9b34d6d0e25363ceda3a6ba9dcec3 Mon Sep 17 00:00:00 2001
From: Nicholas Nethercote <nnethercote@mozilla.com>
Date: Fri, 9 Nov 2018 10:10:46 +1100
Subject: [PATCH 3/4] Add a static assertion about the size of `ast::Expr`.
---
src/libsyntax/ast.rs | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index 2f17bc0548c..fa6fe347833 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -20,6 +20,7 @@ use print::pprust;
use ptr::P;
use rustc_data_structures::indexed_vec;
use rustc_data_structures::indexed_vec::Idx;
+use rustc_data_structures::static_assert;
use rustc_target::spec::abi::Abi;
use source_map::{dummy_spanned, respan, Spanned};
use symbol::{keywords, Symbol};
@@ -924,6 +925,10 @@ pub struct Expr {
pub attrs: ThinVec<Attribute>,
}
+// `Expr` is used a lot. Make sure it doesn't unintentionally get bigger.
+#[cfg(target_arch = "x86_64")]
+static_assert!(MEM_SIZE_OF_EXPR: std::mem::size_of::<Expr>() == 88);
+
impl Expr {
/// Whether this expression would be valid somewhere that expects a value, for example, an `if`
/// condition.
From 2bd4d5b1a0b05827401970f0cfbe17e6b6f32d0d Mon Sep 17 00:00:00 2001
From: Nicholas Nethercote <nnethercote@mozilla.com>
Date: Tue, 13 Nov 2018 06:34:11 +1100
Subject: [PATCH 4/4] Move two `static_assert!`s to better spots.
And make them x86_64-only so they can use `==` instead of `<=`.
---
src/librustc/ty/context.rs | 6 ------
src/librustc/ty/mod.rs | 4 ++++
src/librustc/ty/sty.rs | 4 ++++
src/libsyntax/ast.rs | 1 +
4 files changed, 9 insertions(+), 6 deletions(-)
diff --git a/src/librustc/ty/context.rs b/src/librustc/ty/context.rs
index 82095a2f5b0..f78fad9f7aa 100644
--- a/src/librustc/ty/context.rs
+++ b/src/librustc/ty/context.rs
@@ -823,12 +823,6 @@ impl<'a, 'gcx> HashStable<StableHashingContext<'a>> for TypeckTables<'gcx> {
impl<'tcx> CommonTypes<'tcx> {
fn new(interners: &CtxtInterners<'tcx>) -> CommonTypes<'tcx> {
- // Ensure our type representation does not grow
- #[cfg(target_pointer_width = "64")]
- static_assert!(ASSERT_TY_KIND: ::std::mem::size_of::<ty::TyKind<'_>>() <= 24);
- #[cfg(target_pointer_width = "64")]
- static_assert!(ASSERT_TYS: ::std::mem::size_of::<ty::TyS<'_>>() <= 32);
-
let mk = |sty| CtxtInterners::intern_ty(interners, interners, sty);
let mk_region = |r| {
if let Some(r) = interners.region.borrow().get(&r) {
diff --git a/src/librustc/ty/mod.rs b/src/librustc/ty/mod.rs
index ef9b3e3efab..32503426135 100644
--- a/src/librustc/ty/mod.rs
+++ b/src/librustc/ty/mod.rs
@@ -514,6 +514,10 @@ pub struct TyS<'tcx> {
outer_exclusive_binder: ty::DebruijnIndex,
}
+// `TyS` is used a lot. Make sure it doesn't unintentionally get bigger.
+#[cfg(target_arch = "x86_64")]
+static_assert!(MEM_SIZE_OF_TY_S: ::std::mem::size_of::<TyS<'_>>() == 32);
+
impl<'tcx> Ord for TyS<'tcx> {
fn cmp(&self, other: &TyS<'tcx>) -> Ordering {
self.sty.cmp(&other.sty)
diff --git a/src/librustc/ty/sty.rs b/src/librustc/ty/sty.rs
index a4130bf15cb..bd3a34cae90 100644
--- a/src/librustc/ty/sty.rs
+++ b/src/librustc/ty/sty.rs
@@ -211,6 +211,10 @@ pub enum TyKind<'tcx> {
Error,
}
+// `TyKind` is used a lot. Make sure it doesn't unintentionally get bigger.
+#[cfg(target_arch = "x86_64")]
+static_assert!(MEM_SIZE_OF_TY_KIND: ::std::mem::size_of::<TyKind<'_>>() == 24);
+
/// A closure can be modeled as a struct that looks like:
///
/// struct Closure<'l0...'li, T0...Tj, CK, CS, U0...Uk> {
diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index fa6fe347833..808e19d6f12 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -20,6 +20,7 @@ use print::pprust;
use ptr::P;
use rustc_data_structures::indexed_vec;
use rustc_data_structures::indexed_vec::Idx;
+#[cfg(target_arch = "x86_64")]
use rustc_data_structures::static_assert;
use rustc_target::spec::abi::Abi;
use source_map::{dummy_spanned, respan, Spanned};