Rollup of 10 pull requests

compiler/rustc_codegen_gcc/src/intrinsic/mod.rs

@@ -316,7 +316,7 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallMethods<'tcx> for Builder<'a, 'gcc, 'tcx> {
                     extended_asm.add_input_operand(None, "r", result.llval);
                     extended_asm.add_clobber("memory");
                     extended_asm.set_volatile_flag(true);
-                    
+
                     // We have copied the value to `result` already.
                     return;
                 }
@@ -363,10 +363,6 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallMethods<'tcx> for Builder<'a, 'gcc, 'tcx> {
         cond
     }
 
-    fn sideeffect(&mut self) {
-        // TODO(antoyo)
-    }
-
     fn type_test(&mut self, _pointer: Self::Value, _typeid: Self::Value) -> Self::Value {
         // Unsupported.
         self.context.new_rvalue_from_int(self.int_type, 0)

compiler/rustc_codegen_llvm/src/context.rs

@@ -597,7 +597,6 @@ impl CodegenCx<'b, 'tcx> {
         ifn!("llvm.trap", fn() -> void);
         ifn!("llvm.debugtrap", fn() -> void);
         ifn!("llvm.frameaddress", fn(t_i32) -> i8p);
-        ifn!("llvm.sideeffect", fn() -> void);
 
         ifn!("llvm.powi.f32", fn(t_f32, t_i32) -> t_f32);
         ifn!("llvm.powi.f64", fn(t_f64, t_i32) -> t_f64);

compiler/rustc_codegen_llvm/src/intrinsic.rs

@@ -392,15 +392,6 @@ impl IntrinsicCallMethods<'tcx> for Builder<'a, 'll, 'tcx> {
         self.call_intrinsic("llvm.expect.i1", &[cond, self.const_bool(expected)])
     }
 
-    fn sideeffect(&mut self) {
-        // This kind of check would make a ton of sense in the caller, but currently the only
-        // caller of this function is in `rustc_codegen_ssa`, which is agnostic to whether LLVM
-        // codegen backend being used, and so is unable to check the LLVM version.
-        if unsafe { llvm::LLVMRustVersionMajor() } < 12 {
-            self.call_intrinsic("llvm.sideeffect", &[]);
-        }
-    }
-
     fn type_test(&mut self, pointer: Self::Value, typeid: Self::Value) -> Self::Value {
         // Test the called operand using llvm.type.test intrinsic. The LowerTypeTests link-time
         // optimization pass replaces calls to this intrinsic with code to test type membership.

compiler/rustc_codegen_ssa/src/mir/block.rs

@@ -980,17 +980,6 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             }
 
             mir::TerminatorKind::Goto { target } => {
-                if bb == target {
-                    // This is an unconditional branch back to this same basic block. That means we
-                    // have something like a `loop {}` statement. LLVM versions before 12.0
-                    // miscompile this because they assume forward progress. For older versions
-                    // try to handle just this specific case which comes up commonly in practice
-                    // (e.g., in embedded code).
-                    //
-                    // NB: the `sideeffect` currently checks for the LLVM version used internally.
-                    bx.sideeffect();
-                }
-
                 helper.funclet_br(self, &mut bx, target);
             }
 

compiler/rustc_codegen_ssa/src/traits/intrinsic.rs

@@ -20,10 +20,6 @@ pub trait IntrinsicCallMethods<'tcx>: BackendTypes {
     fn abort(&mut self);
     fn assume(&mut self, val: Self::Value);
     fn expect(&mut self, cond: Self::Value, expected: bool) -> Self::Value;
-    /// Emits a forced side effect.
-    ///
-    /// Currently has any effect only when LLVM versions prior to 12.0 are used as the backend.
-    fn sideeffect(&mut self);
     /// Trait method used to test whether a given pointer is associated with a type identifier.
     fn type_test(&mut self, pointer: Self::Value, typeid: Self::Value) -> Self::Value;
     /// Trait method used to inject `va_start` on the "spoofed" `VaListImpl` in

compiler/rustc_data_structures/src/sorted_map/index_map.rs

@@ -34,39 +34,47 @@ pub struct SortedIndexMultiMap<I: Idx, K, V> {
 }
 
 impl<I: Idx, K: Ord, V> SortedIndexMultiMap<I, K, V> {
+    #[inline]
     pub fn new() -> Self {
         SortedIndexMultiMap { items: IndexVec::new(), idx_sorted_by_item_key: Vec::new() }
     }
 
+    #[inline]
     pub fn len(&self) -> usize {
         self.items.len()
     }
 
+    #[inline]
     pub fn is_empty(&self) -> bool {
         self.items.is_empty()
     }
 
     /// Returns an iterator over the items in the map in insertion order.
+    #[inline]
     pub fn into_iter(self) -> impl DoubleEndedIterator<Item = (K, V)> {
         self.items.into_iter()
     }
 
     /// Returns an iterator over the items in the map in insertion order along with their indices.
+    #[inline]
     pub fn into_iter_enumerated(self) -> impl DoubleEndedIterator<Item = (I, (K, V))> {
         self.items.into_iter_enumerated()
     }
 
     /// Returns an iterator over the items in the map in insertion order.
+    #[inline]
     pub fn iter(&self) -> impl '_ + DoubleEndedIterator<Item = (&K, &V)> {
         self.items.iter().map(|(ref k, ref v)| (k, v))
     }
 
     /// Returns an iterator over the items in the map in insertion order along with their indices.
+    #[inline]
     pub fn iter_enumerated(&self) -> impl '_ + DoubleEndedIterator<Item = (I, (&K, &V))> {
         self.items.iter_enumerated().map(|(i, (ref k, ref v))| (i, (k, v)))
     }
 
     /// Returns the item in the map with the given index.
+    #[inline]
     pub fn get(&self, idx: I) -> Option<&(K, V)> {
         self.items.get(idx)
     }
@@ -75,6 +83,7 @@ impl<I: Idx, K: Ord, V> SortedIndexMultiMap<I, K, V> {
     ///
     /// If there are multiple items that are equivalent to `key`, they will be yielded in
     /// insertion order.
+    #[inline]
     pub fn get_by_key(&'a self, key: K) -> impl 'a + Iterator<Item = &'a V> {
         self.get_by_key_enumerated(key).map(|(_, v)| v)
     }
@@ -84,6 +93,7 @@ impl<I: Idx, K: Ord, V> SortedIndexMultiMap<I, K, V> {
     ///
     /// If there are multiple items that are equivalent to `key`, they will be yielded in
     /// insertion order.
+    #[inline]
     pub fn get_by_key_enumerated(&'a self, key: K) -> impl '_ + Iterator<Item = (I, &V)> {
         let lower_bound = self.idx_sorted_by_item_key.partition_point(|&i| self.items[i].0 < key);
         self.idx_sorted_by_item_key[lower_bound..].iter().map_while(move |&i| {