Merge #51

51: Test miri on CI r=Amanieu a=gnzlbg



Co-authored-by: gnzlbg <[email protected]>

Author: bors[bot]

.travis.yml

@@ -3,6 +3,15 @@ sudo: false
 
 matrix:
   include:
+    - name: "miri"
+      rust: nightly
+      install:
+        - rustup component add rust-src
+        - cargo +nightly install --force --git https://github.com/rust-lang/miri miri
+        - cargo install xargo
+      script:
+        - cargo clean
+        - cargo +nightly miri test
     - rust: 1.29.0
     - rust: stable
     - rust: beta

src/lib.rs

@@ -43,6 +43,9 @@ extern crate serde;
 #[cfg_attr(test, macro_use)]
 extern crate std as alloc;
 
+#[macro_use]
+mod macros;
+
 mod external_trait_impls;
 mod fx;
 mod map;

src/macros.rs

@@ -0,0 +1,54 @@
+// See the cfg-if crate.
+macro_rules! cfg_if {
+    // match if/else chains with a final `else`
+    ($(
+        if #[cfg($($meta:meta),*)] { $($it:item)* }
+    ) else * else {
+        $($it2:item)*
+    }) => {
+        cfg_if! {
+            @__items
+            () ;
+            $( ( ($($meta),*) ($($it)*) ), )*
+            ( () ($($it2)*) ),
+        }
+    };
+
+    // match if/else chains lacking a final `else`
+    (
+        if #[cfg($($i_met:meta),*)] { $($i_it:item)* }
+        $(
+            else if #[cfg($($e_met:meta),*)] { $($e_it:item)* }
+        )*
+    ) => {
+        cfg_if! {
+            @__items
+            () ;
+            ( ($($i_met),*) ($($i_it)*) ),
+            $( ( ($($e_met),*) ($($e_it)*) ), )*
+            ( () () ),
+        }
+    };
+
+    // Internal and recursive macro to emit all the items
+    //
+    // Collects all the negated cfgs in a list at the beginning and after the
+    // semicolon is all the remaining items
+    (@__items ($($not:meta,)*) ; ) => {};
+    (@__items ($($not:meta,)*) ; ( ($($m:meta),*) ($($it:item)*) ), $($rest:tt)*) => {
+        // Emit all items within one block, applying an approprate #[cfg]. The
+        // #[cfg] will require all `$m` matchers specified and must also negate
+        // all previous matchers.
+        cfg_if! { @__apply cfg(all($($m,)* not(any($($not),*)))), $($it)* }
+
+        // Recurse to emit all other items in `$rest`, and when we do so add all
+        // our `$m` matchers to the list of `$not` matchers as future emissions
+        // will have to negate everything we just matched as well.
+        cfg_if! { @__items ($($not,)* $($m,)*) ; $($rest)* }
+    };
+
+    // Internal macro to Apply a cfg attribute to a list of items
+    (@__apply $m:meta, $($it:item)*) => {
+        $(#[$m] $it)*
+    };
+}

src/map.rs

@@ -2513,10 +2513,11 @@ mod test_map {
     use super::DefaultHashBuilder;
     use super::Entry::{Occupied, Vacant};
     use super::HashMap;
-    use rand::{thread_rng, Rng};
+    use rand::{rngs::SmallRng, Rng, SeedableRng};
     use std::cell::RefCell;
     use std::usize;
     use std::vec::Vec;
+    #[cfg(not(miri))]
     use CollectionAllocErr::*;
 
     #[test]
@@ -2770,6 +2771,7 @@ mod test_map {
     }
 
     #[test]
+    #[cfg(not(miri))] // FIXME: https://github.com/rust-lang/miri/issues/654
     fn test_lots_of_insertions() {
         let mut m = HashMap::new();
 
@@ -3191,6 +3193,7 @@ mod test_map {
 
     #[test]
     #[should_panic]
+    #[cfg(not(miri))] // FIXME: https://github.com/rust-lang/miri/issues/636
     fn test_index_nonexistent() {
         let mut map = HashMap::new();
 
@@ -3262,7 +3265,12 @@ mod test_map {
         }
 
         let mut m = HashMap::new();
-        let mut rng = thread_rng();
+
+        // FIXME: https://github.com/rust-lang/miri/issues/653
+        let mut rng = {
+            let seed = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16];
+            SmallRng::from_seed(seed)
+        };
 
         // Populate the map with some items.
         for _ in 0..50 {
@@ -3372,6 +3380,7 @@ mod test_map {
     }
 
     #[test]
+    #[cfg(not(miri))] // FIXME: https://github.com/rust-lang/miri/issues/655
     fn test_try_reserve() {
         let mut empty_bytes: HashMap<u8, u8> = HashMap::new();
 

src/raw/mod.rs

@@ -36,26 +36,27 @@ unsafe fn offset_from<T>(to: *const T, from: *const T) -> usize {
     (to as usize - from as usize) / mem::size_of::<T>()
 }
 
-// Use the SSE2 implementation if possible: it allows us to scan 16 buckets at
-// once instead of 8. We don't bother with AVX since it would require runtime
-// dispatch and wouldn't gain us much anyways: the probability of finding a
-// match drops off drastically after the first few buckets.
-//
-// I attempted an implementation on ARM using NEON instructions, but it turns
-// out that most NEON instructions have multi-cycle latency, which in the end
-// outweighs any gains over the generic implementation.
-#[cfg(all(
-    target_feature = "sse2",
-    any(target_arch = "x86", target_arch = "x86_64")
-))]
-#[path = "sse2.rs"]
-mod imp;
-#[cfg(not(all(
-    target_feature = "sse2",
-    any(target_arch = "x86", target_arch = "x86_64")
-)))]
-#[path = "generic.rs"]
-mod imp;
+cfg_if! {
+    // Use the SSE2 implementation if possible: it allows us to scan 16 buckets
+    // at once instead of 8. We don't bother with AVX since it would require
+    // runtime dispatch and wouldn't gain us much anyways: the probability of
+    // finding a match drops off drastically after the first few buckets.
+    //
+    // I attempted an implementation on ARM using NEON instructions, but it
+    // turns out that most NEON instructions have multi-cycle latency, which in
+    // the end outweighs any gains over the generic implementation.
+    if #[cfg(all(
+        target_feature = "sse2",
+        any(target_arch = "x86", target_arch = "x86_64"),
+        not(miri)
+    ))] {
+        #[path = "sse2.rs"]
+        mod imp;
+    } else {
+        #[path = "generic.rs"]
+        mod imp;
+    }
+}
 
 mod bitmask;
 

tests/set.rs

@@ -1,3 +1,4 @@
+#![cfg(not(miri))] // FIXME: takes too long
 extern crate hashbrown;
 extern crate rand;