rustup: more flexible write_bytes avoids allocations and removes itertools dependency

diff --git a/Cargo.lock b/Cargo.lock
index 0f04aa04bb4546eac780668c1149d5fcb3703eef..1aa15f8b6846a50f421b1e1164341a55c2b13914 100644 (file)
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -215,11 +215,6 @@ dependencies = [
  "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "either"
-version = "1.5.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
 [[package]]
 name = "env_logger"
 version = "0.6.2"
@@ -299,14 +294,6 @@ dependencies = [
  "quick-error 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "itertools"
-version = "0.8.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "either 1.5.3 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "itoa"
 version = "0.4.4"
@@ -365,7 +352,6 @@ dependencies = [
  "env_logger 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "getrandom 0.1.12 (registry+https://github.com/rust-lang/crates.io-index)",
  "hex 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "itertools 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "num-traits 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -849,7 +835,6 @@ dependencies = [
 "checksum diff 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)" = "3c2b69f912779fbb121ceb775d74d51e915af17aaebc38d28a592843a2dd0a3a"
 "checksum directories 2.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "551a778172a450d7fc12e629ca3b0428d00f6afa9a43da1b630d54604e97371c"
 "checksum dirs-sys 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "afa0b23de8fd801745c471deffa6e12d248f962c9fd4b4c33787b055599bde7b"
-"checksum either 1.5.3 (registry+https://github.com/rust-lang/crates.io-index)" = "bb1f6b1ce1c140482ea30ddd3335fc0024ac7ee112895426e0a629a6c20adfe3"
 "checksum env_logger 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)" = "aafcde04e90a5226a6443b7aabdb016ba2f8307c847d524724bd9b346dd1a2d3"
 "checksum failure 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "f8273f13c977665c5db7eb2b99ae520952fe5ac831ae4cd09d80c4c7042b5ed9"
 "checksum failure_derive 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "0bc225b78e0391e4b8683440bf2e63c2deeeb2ce5189eab46e2b68c6d3725d08"
@@ -859,7 +844,6 @@ dependencies = [
 "checksum getrandom 0.1.12 (registry+https://github.com/rust-lang/crates.io-index)" = "473a1265acc8ff1e808cd0a1af8cee3c2ee5200916058a2ca113c29f2d903571"
 "checksum hex 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "805026a5d0141ffc30abb3be3173848ad46a1b1664fe632428479619a3644d77"
 "checksum humantime 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "df004cfca50ef23c36850aaaa59ad52cc70d0e90243c3c7737a4dd32dc7a3c4f"
-"checksum itertools 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "5b8467d9c1cebe26feb08c640139247fac215782d35371ade9a2136ed6085358"
 "checksum itoa 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)" = "501266b7edd0174f8530248f87f99c88fbe60ca4ef3dd486835b8d8d53136f7f"
 "checksum kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7507624b29483431c0ba2d82aece8ca6cdba9382bff4ddd0f7490560c056098d"
 "checksum lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"

diff --git a/Cargo.toml b/Cargo.toml
index 4c39341e10c1456339cb08aa478c9434a8378ddc..6e317ce9459704460419664c95813efb0ea2d637 100644 (file)
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -40,7 +40,6 @@ log = "0.4"
 shell-escape = "0.1.4"
 hex = "0.3.2"
 rand = "0.7"
-itertools = "0.8"
 
 # A noop dependency that changes in the Rust repository, it's a bit of a hack.
 # See the `src/tools/rustc-workspace-hack/README.md` file in `rust-lang/rust`

diff --git a/rust-version b/rust-version
index 42aa6d8d76a0348c9f012f7312cdcb60388e2820..543d4e269d410c996b0ef876ad567f8b3d59bcc8 100644 (file)
--- a/rust-version
+++ b/rust-version
@@ -1 +1 @@
-f466f52c1bf8f2e4454e31c683a88625ad4b4033
+55e00631e5bc5b16d40232914e57deeea197a8e4

diff --git a/src/helpers.rs b/src/helpers.rs
index 0245540debbe74bf18b5d18c4d1b3b3df6781fc1..f7be3de8e481227ba2d0077d757ec4d146bf9822 100644 (file)
--- a/src/helpers.rs
+++ b/src/helpers.rs
@@ -1,4 +1,4 @@
-use std::mem;
+use std::{mem, iter};
 use std::ffi::{OsStr, OsString};
 
 use rustc::hir::def_id::{DefId, CRATE_DEF_INDEX};
@@ -428,7 +428,7 @@ fn write_os_str_to_c_string(
             return Ok(false);
         }
         // FIXME: We should use `Iterator::chain` instead when rust-lang/rust#65704 lands.
-        self.eval_context_mut().memory.write_bytes(scalar, [bytes, &[0]].concat())?;
+        self.eval_context_mut().memory.write_bytes(scalar, bytes.iter().copied().chain(iter::once(0u8)))?;
         Ok(true)
     }
 }

diff --git a/src/shims/foreign_items.rs b/src/shims/foreign_items.rs
index 66fb53581e680da4b3ecf403f1aae4a4af0f55b7..dea01c63a05b9fb61052c4636d75235f7585c427 100644 (file)
--- a/src/shims/foreign_items.rs
+++ b/src/shims/foreign_items.rs
@@ -1,4 +1,4 @@
-use std::convert::TryInto;
+use std::{iter, convert::TryInto};
 
 use rustc::hir::def_id::DefId;
 use rustc::mir;
@@ -52,7 +52,7 @@ fn malloc(&mut self, size: u64, zero_init: bool, kind: MiriMemoryKind) -> Scalar
             if zero_init {
                 // We just allocated this, the access is definitely in-bounds.
                 this.memory
-                    .write_bytes(ptr.into(), itertools::repeat_n(0u8, size as usize))
+                    .write_bytes(ptr.into(), iter::repeat(0u8).take(size as usize))
                     .unwrap();
             }
             Scalar::Ptr(ptr)
@@ -227,7 +227,7 @@ fn emulate_foreign_item(
                 );
                 // We just allocated this, the access is definitely in-bounds.
                 this.memory
-                    .write_bytes(ptr.into(), itertools::repeat_n(0u8, size as usize))
+                    .write_bytes(ptr.into(), iter::repeat(0u8).take(size as usize))
                     .unwrap();
                 this.write_scalar(Scalar::Ptr(ptr), dest)?;
             }
@@ -839,7 +839,7 @@ fn emulate_foreign_item(
                 let system_info = this.deref_operand(args[0])?;
                 // Initialize with `0`.
                 this.memory
-                    .write_bytes(system_info.ptr, itertools::repeat_n(0, system_info.layout.size.bytes() as usize))?;
+                    .write_bytes(system_info.ptr, iter::repeat(0u8).take(system_info.layout.size.bytes() as usize))?;
                 // Set number of processors.
                 let dword_size = Size::from_bytes(4);
                 let num_cpus = this.mplace_field(system_info, 6)?;

diff --git a/src/shims/intrinsics.rs b/src/shims/intrinsics.rs
index d39e70d8990fbfefd8db05815d9f8d3abe946778..5ef7fba7f59083b093902b40a094b4b2fe851d95 100644 (file)
--- a/src/shims/intrinsics.rs
+++ b/src/shims/intrinsics.rs
@@ -1,3 +1,5 @@
+use std::iter;
+
 use rustc_apfloat::Float;
 use rustc::mir;
 use rustc::mir::interpret::{InterpResult, PointerArithmetic};
@@ -357,7 +359,7 @@ fn call_intrinsic(
                             // Do it in memory
                             let mplace = this.force_allocation(dest)?;
                             mplace.meta.unwrap_none(); // must be sized
-                            this.memory.write_bytes(mplace.ptr, itertools::repeat_n(0, dest.layout.size.bytes() as usize))?;
+                            this.memory.write_bytes(mplace.ptr, iter::repeat(0u8).take(dest.layout.size.bytes() as usize))?;
                         }
                     }
                 }
@@ -562,7 +564,7 @@ fn call_intrinsic(
                 let ptr = this.read_scalar(args[0])?.not_undef()?;
                 let count = this.read_scalar(args[2])?.to_usize(this)?;
                 let byte_count = ty_layout.size * count;
-                this.memory.write_bytes(ptr, itertools::repeat_n(val_byte, byte_count.bytes() as usize))?;
+                this.memory.write_bytes(ptr, iter::repeat(val_byte).take(byte_count.bytes() as usize))?;
             }
 
             name => throw_unsup_format!("unimplemented intrinsic: {}", name),