move things from rustc_target::abi to rustc_abi

Author: HKalbasi

Cargo.lock

@@ -3202,6 +3202,20 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "rustc_abi"
+version = "0.0.0"
+dependencies = [
+ "bitflags",
+ "rand 0.8.5",
+ "rand_xoshiro",
+ "rustc_data_structures",
+ "rustc_index",
+ "rustc_macros",
+ "rustc_serialize",
+ "tracing",
+]
+
 [[package]]
 name = "rustc_apfloat"
 version = "0.0.0"
@@ -4281,8 +4295,7 @@ name = "rustc_target"
 version = "0.0.0"
 dependencies = [
  "bitflags",
- "rand 0.8.5",
- "rand_xoshiro",
+ "rustc_abi",
  "rustc_data_structures",
  "rustc_feature",
  "rustc_index",
@@ -4363,8 +4376,6 @@ dependencies = [
 name = "rustc_ty_utils"
 version = "0.0.0"
 dependencies = [
- "rand 0.8.5",
- "rand_xoshiro",
  "rustc_data_structures",
  "rustc_errors",
  "rustc_hir",

compiler/rustc_abi/Cargo.toml

@@ -0,0 +1,24 @@
+[package]
+name = "rustc_abi"
+version = "0.0.0"
+edition = "2021"
+
+[dependencies]
+bitflags = "1.2.1"
+tracing = "0.1"
+rand = { version = "0.8.4", default-features = false, optional = true }
+rand_xoshiro = { version = "0.6.0", optional = true }
+rustc_data_structures = { path = "../rustc_data_structures", optional = true  }
+rustc_index = { path = "../rustc_index", default-features = false }
+rustc_macros = { path = "../rustc_macros", optional = true }
+rustc_serialize = { path = "../rustc_serialize", optional = true  }
+
+[features]
+default = ["nightly", "randomize"]
+randomize = ["rand", "rand_xoshiro"]
+nightly = [
+    "rustc_data_structures",
+    "rustc_index/nightly",
+    "rustc_macros",
+    "rustc_serialize",
+]

compiler/rustc_target/src/abi/layout.rs renamed to compiler/rustc_abi/src/layout.rs

@@ -7,7 +7,9 @@ use std::{
     ops::{Bound, Deref},
 };
 
+#[cfg(feature = "randomize")]
 use rand::{seq::SliceRandom, SeedableRng};
+#[cfg(feature = "randomize")]
 use rand_xoshiro::Xoshiro128StarStar;
 
 use tracing::debug;
@@ -91,14 +93,16 @@ pub trait LayoutCalculator {
             // If `-Z randomize-layout` was enabled for the type definition we can shuffle
             // the field ordering to try and catch some code making assumptions about layouts
             // we don't guarantee
-            if repr.can_randomize_type_layout() {
-                // `ReprOptions.layout_seed` is a deterministic seed that we can use to
-                // randomize field ordering with
-                let mut rng = Xoshiro128StarStar::seed_from_u64(repr.field_shuffle_seed);
-
-                // Shuffle the ordering of the fields
-                optimizing.shuffle(&mut rng);
+            if repr.can_randomize_type_layout() && cfg!(feature = "randomize") {
+                #[cfg(feature = "randomize")]
+                {
+                    // `ReprOptions.layout_seed` is a deterministic seed that we can use to
+                    // randomize field ordering with
+                    let mut rng = Xoshiro128StarStar::seed_from_u64(repr.field_shuffle_seed);
 
+                    // Shuffle the ordering of the fields
+                    optimizing.shuffle(&mut rng);
+                }
                 // Otherwise we just leave things alone and actually optimize the type's fields
             } else {
                 match kind {
@@ -900,7 +904,7 @@ pub trait LayoutCalculator {
         let mut abi = Abi::Aggregate { sized: true };
         let index = V::new(0);
         for field in &variants[index] {
-            assert!(!field.is_unsized());
+            assert!(field.is_sized());
             align = align.max(field.align);
 
             // If all non-ZST fields have the same ABI, forward this ABI