diff --git a/cranelift/src/cton-util.rs b/cranelift/src/cton-util.rs
index 681ab5b8bc..fea4d879be 100644
--- a/cranelift/src/cton-util.rs
+++ b/cranelift/src/cton-util.rs
@@ -51,7 +51,11 @@ pub type CommandResult = Result<(), String>;
 fn cton_util() -> CommandResult {
     // Parse comand line arguments.
     let args: Args = Docopt::new(USAGE)
-        .and_then(|d| d.help(true).version(Some(format!("Cretonne {}", VERSION))).decode())
+        .and_then(|d| {
+                      d.help(true)
+                          .version(Some(format!("Cretonne {}", VERSION)))
+                          .decode()
+                  })
         .unwrap_or_else(|e| e.exit());
 
     // Find the sub-command to execute.
diff --git a/cranelift/src/filetest/concurrent.rs b/cranelift/src/filetest/concurrent.rs
index effe454d38..9ea1114000 100644
--- a/cranelift/src/filetest/concurrent.rs
+++ b/cranelift/src/filetest/concurrent.rs
@@ -119,10 +119,11 @@ fn worker_thread(thread_num: usize,
 
                 // Tell them we're starting this job.
                 // The receiver should always be present for this as long as we have jobs.
-                replies.send(Reply::Starting {
-                                 jobid: jobid,
-                                 thread_num: thread_num,
-                             })
+                replies
+                    .send(Reply::Starting {
+                              jobid: jobid,
+                              thread_num: thread_num,
+                          })
                     .unwrap();
 
                 let result = catch_unwind(|| runone::run(path.as_path())).unwrap_or_else(|e| {
@@ -141,10 +142,11 @@ fn worker_thread(thread_num: usize,
                     dbg!("FAIL: {}", msg);
                 }
 
-                replies.send(Reply::Done {
-                                 jobid: jobid,
-                                 result: result,
-                             })
+                replies
+                    .send(Reply::Done {
+                              jobid: jobid,
+                              result: result,
+                          })
                     .unwrap();
             }
         })
diff --git a/cranelift/src/filetest/legalizer.rs b/cranelift/src/filetest/legalizer.rs
index 39854769ac..1a5f774664 100644
--- a/cranelift/src/filetest/legalizer.rs
+++ b/cranelift/src/filetest/legalizer.rs
@@ -41,7 +41,8 @@ impl SubTest for TestLegalizer {
 
         comp_ctx.flowgraph();
         comp_ctx.legalize(isa);
-        comp_ctx.verify(isa).map_err(|e| pretty_verifier_error(&comp_ctx.func, e))?;
+        comp_ctx.verify(isa)
+            .map_err(|e| pretty_verifier_error(&comp_ctx.func, e))?;
 
         let mut text = String::new();
         write_function(&mut text, &comp_ctx.func, Some(isa)).map_err(|e| e.to_string())?;
diff --git a/cranelift/src/filetest/regalloc.rs b/cranelift/src/filetest/regalloc.rs
index 5f70f51100..daf7adcb07 100644
--- a/cranelift/src/filetest/regalloc.rs
+++ b/cranelift/src/filetest/regalloc.rs
@@ -47,7 +47,8 @@ impl SubTest for TestRegalloc {
         // TODO: Should we have an option to skip legalization?
         comp_ctx.legalize(isa);
         comp_ctx.regalloc(isa);
-        comp_ctx.verify(isa).map_err(|e| pretty_verifier_error(&comp_ctx.func, e))?;
+        comp_ctx.verify(isa)
+            .map_err(|e| pretty_verifier_error(&comp_ctx.func, e))?;
 
         let mut text = String::new();
         write_function(&mut text, &comp_ctx.func, Some(isa)).map_err(|e| e.to_string())?;
diff --git a/cranelift/src/filetest/runner.rs b/cranelift/src/filetest/runner.rs
index 91331a0299..1993ca5877 100644
--- a/cranelift/src/filetest/runner.rs
+++ b/cranelift/src/filetest/runner.rs
@@ -104,10 +104,11 @@ impl TestRunner {
     ///
     /// Any problems reading `file` as a test case file will be reported as a test failure.
     pub fn push_test<P: Into<PathBuf>>(&mut self, file: P) {
-        self.tests.push(QueueEntry {
-                            path: file.into(),
-                            state: State::New,
-                        });
+        self.tests
+            .push(QueueEntry {
+                      path: file.into(),
+                      state: State::New,
+                  });
     }
 
     /// Begin running tests concurrently.
@@ -206,7 +207,9 @@ impl TestRunner {
         }
 
         // Check for any asynchronous replies without blocking.
-        while let Some(reply) = self.threads.as_mut().and_then(ConcurrentRunner::try_get) {
+        while let Some(reply) = self.threads
+                  .as_mut()
+                  .and_then(ConcurrentRunner::try_get) {
             self.handle_reply(reply);
         }
     }
@@ -303,12 +306,12 @@ impl TestRunner {
             return;
         }
 
-        for t in self.tests.iter().filter(|entry| match **entry {
-                                              QueueEntry { state: State::Done(Ok(dur)), .. } => {
-                                                  dur > cut
-                                              }
-                                              _ => false,
-                                          }) {
+        for t in self.tests
+                .iter()
+                .filter(|entry| match **entry {
+                            QueueEntry { state: State::Done(Ok(dur)), .. } => dur > cut,
+                            _ => false,
+                        }) {
             println!("slow: {}", t)
         }
 
diff --git a/cranelift/src/filetest/runone.rs b/cranelift/src/filetest/runone.rs
index ec61c98240..bc16725d74 100644
--- a/cranelift/src/filetest/runone.rs
+++ b/cranelift/src/filetest/runone.rs
@@ -120,5 +120,6 @@ fn run_one_test<'a>(tuple: (&'a SubTest, &'a Flags, Option<&'a TargetIsa>),
         context.verified = true;
     }
 
-    test.run(func, context).map_err(|e| format!("{}: {}", name, e))
+    test.run(func, context)
+        .map_err(|e| format!("{}: {}", name, e))
 }
diff --git a/cranelift/src/filetest/subtest.rs b/cranelift/src/filetest/subtest.rs
index ede013ef9f..923439d490 100644
--- a/cranelift/src/filetest/subtest.rs
+++ b/cranelift/src/filetest/subtest.rs
@@ -76,11 +76,13 @@ impl<'a> filecheck::VariableMap for Context<'a> {
 /// Run filecheck on `text`, using directives extracted from `context`.
 pub fn run_filecheck(text: &str, context: &Context) -> Result<()> {
     let checker = build_filechecker(context)?;
-    if checker.check(&text, context).map_err(|e| format!("filecheck: {}", e))? {
+    if checker.check(&text, context)
+           .map_err(|e| format!("filecheck: {}", e))? {
         Ok(())
     } else {
         // Filecheck mismatch. Emit an explanation as output.
-        let (_, explain) = checker.explain(&text, context).map_err(|e| format!("explain: {}", e))?;
+        let (_, explain) = checker.explain(&text, context)
+            .map_err(|e| format!("explain: {}", e))?;
         Err(format!("filecheck failed:\n{}{}", checker, explain))
     }
 }
@@ -90,10 +92,12 @@ pub fn build_filechecker(context: &Context) -> Result<Checker> {
     let mut builder = CheckerBuilder::new();
     // Preamble comments apply to all functions.
     for comment in context.preamble_comments {
-        builder.directive(comment.text).map_err(|e| format!("filecheck: {}", e))?;
+        builder.directive(comment.text)
+            .map_err(|e| format!("filecheck: {}", e))?;
     }
     for comment in &context.details.comments {
-        builder.directive(comment.text).map_err(|e| format!("filecheck: {}", e))?;
+        builder.directive(comment.text)
+            .map_err(|e| format!("filecheck: {}", e))?;
     }
     let checker = builder.finish();
     if checker.is_empty() {
diff --git a/cranelift/src/rsfilecheck.rs b/cranelift/src/rsfilecheck.rs
index 734c067a36..79d913bce9 100644
--- a/cranelift/src/rsfilecheck.rs
+++ b/cranelift/src/rsfilecheck.rs
@@ -18,10 +18,12 @@ pub fn run(files: Vec<String>, verbose: bool) -> CommandResult {
     }
 
     let mut buffer = String::new();
-    io::stdin().read_to_string(&mut buffer).map_err(|e| format!("stdin: {}", e))?;
+    io::stdin().read_to_string(&mut buffer)
+        .map_err(|e| format!("stdin: {}", e))?;
 
     if verbose {
-        let (success, explain) = checker.explain(&buffer, NO_VARIABLES).map_err(|e| e.to_string())?;
+        let (success, explain) = checker.explain(&buffer, NO_VARIABLES)
+            .map_err(|e| e.to_string())?;
         print!("{}", explain);
         if success {
             println!("OK");
@@ -29,10 +31,12 @@ pub fn run(files: Vec<String>, verbose: bool) -> CommandResult {
         } else {
             Err("Check failed".to_string())
         }
-    } else if checker.check(&buffer, NO_VARIABLES).map_err(|e| e.to_string())? {
+    } else if checker.check(&buffer, NO_VARIABLES)
+                  .map_err(|e| e.to_string())? {
         Ok(())
     } else {
-        let (_, explain) = checker.explain(&buffer, NO_VARIABLES).map_err(|e| e.to_string())?;
+        let (_, explain) = checker.explain(&buffer, NO_VARIABLES)
+            .map_err(|e| e.to_string())?;
         print!("{}", explain);
         Err("Check failed".to_string())
     }
@@ -41,6 +45,7 @@ pub fn run(files: Vec<String>, verbose: bool) -> CommandResult {
 fn read_checkfile(filename: &str) -> Result<Checker, String> {
     let buffer = read_to_string(&filename).map_err(|e| format!("{}: {}", filename, e))?;
     let mut builder = CheckerBuilder::new();
-    builder.text(&buffer).map_err(|e| format!("{}: {}", filename, e))?;
+    builder.text(&buffer)
+        .map_err(|e| format!("{}: {}", filename, e))?;
     Ok(builder.finish())
 }
diff --git a/cranelift/test-all.sh b/cranelift/test-all.sh
index 7c4938902f..522cf594a2 100755
--- a/cranelift/test-all.sh
+++ b/cranelift/test-all.sh
@@ -30,7 +30,7 @@ function banner() {
 # rustfmt is installed.
 #
 # This version should always be bumped to the newest version available.
-RUSTFMT_VERSION="0.8.0"
+RUSTFMT_VERSION="0.8.1"
 
 if cargo install --list | grep -q "^rustfmt v$RUSTFMT_VERSION"; then
     banner "Rust formatting"
diff --git a/cranelift/tests/cfg_traversal.rs b/cranelift/tests/cfg_traversal.rs
index f7fb119463..903b1a1ec1 100644
--- a/cranelift/tests/cfg_traversal.rs
+++ b/cranelift/tests/cfg_traversal.rs
@@ -9,7 +9,10 @@ use self::cton_reader::parse_functions;
 fn test_reverse_postorder_traversal(function_source: &str, ebb_order: Vec<u32>) {
     let func = &parse_functions(function_source).unwrap()[0];
     let cfg = ControlFlowGraph::with_function(&func);
-    let ebbs = ebb_order.iter().map(|n| Ebb::with_number(*n).unwrap()).collect::<Vec<Ebb>>();
+    let ebbs = ebb_order
+        .iter()
+        .map(|n| Ebb::with_number(*n).unwrap())
+        .collect::<Vec<Ebb>>();
 
     let mut postorder_ebbs = cfg.postorder_ebbs();
     let mut postorder_map = EntityMap::with_capacity(postorder_ebbs.len());
diff --git a/lib/cretonne/src/abi.rs b/lib/cretonne/src/abi.rs
index 14a034b8fb..32210fecfb 100644
--- a/lib/cretonne/src/abi.rs
+++ b/lib/cretonne/src/abi.rs
@@ -108,7 +108,10 @@ pub fn legalize_args<AA: ArgAssigner>(args: &mut Vec<ArgumentType>, aa: &mut AA)
             }
             // Split this argument into two smaller ones. Then revisit both.
             ArgAction::Convert(conv) => {
-                let new_arg = ArgumentType { value_type: conv.apply(arg.value_type), ..arg };
+                let new_arg = ArgumentType {
+                    value_type: conv.apply(arg.value_type),
+                    ..arg
+                };
                 args[argno].value_type = new_arg.value_type;
                 if conv.is_split() {
                     args.insert(argno + 1, new_arg);
diff --git a/lib/cretonne/src/context.rs b/lib/cretonne/src/context.rs
index 2d5631f62c..051adc47aa 100644
--- a/lib/cretonne/src/context.rs
+++ b/lib/cretonne/src/context.rs
@@ -69,6 +69,7 @@ impl Context {
 
     /// Run the register allocator.
     pub fn regalloc(&mut self, isa: &TargetIsa) {
-        self.regalloc.run(isa, &mut self.func, &self.cfg, &self.domtree);
+        self.regalloc
+            .run(isa, &mut self.func, &self.cfg, &self.domtree);
     }
 }
diff --git a/lib/cretonne/src/dominator_tree.rs b/lib/cretonne/src/dominator_tree.rs
index b014e85ec1..13d1175d8a 100644
--- a/lib/cretonne/src/dominator_tree.rs
+++ b/lib/cretonne/src/dominator_tree.rs
@@ -88,7 +88,8 @@ impl DominatorTree {
         // Run a finger up the dominator tree from b until we see a.
         // Do nothing if b is unreachable.
         while rpo_a < self.nodes[ebb_b].rpo_number {
-            b = self.idom(ebb_b).expect("Shouldn't meet unreachable here.");
+            b = self.idom(ebb_b)
+                .expect("Shouldn't meet unreachable here.");
             ebb_b = layout.inst_ebb(b).expect("Dominator got removed.");
         }
 
@@ -209,8 +210,9 @@ impl DominatorTree {
             .filter(|&(ebb, _)| self.is_reachable(ebb));
 
         // The RPO must visit at least one predecessor before this node.
-        let mut idom =
-            reachable_preds.next().expect("EBB node must have one reachable predecessor");
+        let mut idom = reachable_preds
+            .next()
+            .expect("EBB node must have one reachable predecessor");
 
         for pred in reachable_preds {
             idom = self.common_dominator(idom, pred, layout);
diff --git a/lib/cretonne/src/entity_list.rs b/lib/cretonne/src/entity_list.rs
index 1a05464c21..0b90265470 100644
--- a/lib/cretonne/src/entity_list.rs
+++ b/lib/cretonne/src/entity_list.rs
@@ -135,7 +135,9 @@ impl<T: EntityRef> ListPool<T> {
         // The `wrapping_sub` handles the special case 0, which is the empty list. This way, the
         // cost of the bounds check that we have to pay anyway is co-opted to handle the special
         // case of the empty list.
-        self.data.get(idx.wrapping_sub(1)).map(|len| len.index())
+        self.data
+            .get(idx.wrapping_sub(1))
+            .map(|len| len.index())
     }
 
     /// Allocate a storage block with a size given by `sclass`.
diff --git a/lib/cretonne/src/ir/builder.rs b/lib/cretonne/src/ir/builder.rs
index 8880351d9b..fb5c4ba20a 100644
--- a/lib/cretonne/src/ir/builder.rs
+++ b/lib/cretonne/src/ir/builder.rs
@@ -65,10 +65,7 @@ impl<'c, 'fc, 'fd> InsertBuilder<'c, 'fc, 'fd> {
     pub fn new(dfg: &'fd mut DataFlowGraph,
                pos: &'c mut Cursor<'fc>)
                -> InsertBuilder<'c, 'fc, 'fd> {
-        InsertBuilder {
-            dfg: dfg,
-            pos: pos,
-        }
+        InsertBuilder { dfg: dfg, pos: pos }
     }
 }
 
@@ -182,8 +179,9 @@ impl<'f> InstBuilderBase<'f> for ReplaceBuilder<'f> {
 
             // Normally, make_inst_results() would also set the first result type, but we're not
             // going to call that, so set it manually.
-            *self.dfg[self.inst].first_type_mut() =
-                self.dfg.compute_result_type(self.inst, 0, ctrl_typevar).unwrap_or_default();
+            *self.dfg[self.inst].first_type_mut() = self.dfg
+                .compute_result_type(self.inst, 0, ctrl_typevar)
+                .unwrap_or_default();
         }
 
         (self.inst, self.dfg)
diff --git a/lib/cretonne/src/ir/dfg.rs b/lib/cretonne/src/ir/dfg.rs
index f7d214182b..22ce7a116d 100644
--- a/lib/cretonne/src/ir/dfg.rs
+++ b/lib/cretonne/src/ir/dfg.rs
@@ -356,25 +356,37 @@ impl DataFlowGraph {
 
     /// Get the fixed value arguments on `inst` as a slice.
     pub fn inst_fixed_args(&self, inst: Inst) -> &[Value] {
-        let fixed_args = self[inst].opcode().constraints().fixed_value_arguments();
+        let fixed_args = self[inst]
+            .opcode()
+            .constraints()
+            .fixed_value_arguments();
         &self.inst_args(inst)[..fixed_args]
     }
 
     /// Get the fixed value arguments on `inst` as a mutable slice.
     pub fn inst_fixed_args_mut(&mut self, inst: Inst) -> &mut [Value] {
-        let fixed_args = self[inst].opcode().constraints().fixed_value_arguments();
+        let fixed_args = self[inst]
+            .opcode()
+            .constraints()
+            .fixed_value_arguments();
         &mut self.inst_args_mut(inst)[..fixed_args]
     }
 
     /// Get the variable value arguments on `inst` as a slice.
     pub fn inst_variable_args(&self, inst: Inst) -> &[Value] {
-        let fixed_args = self[inst].opcode().constraints().fixed_value_arguments();
+        let fixed_args = self[inst]
+            .opcode()
+            .constraints()
+            .fixed_value_arguments();
         &self.inst_args(inst)[fixed_args..]
     }
 
     /// Get the variable value arguments on `inst` as a mutable slice.
     pub fn inst_variable_args_mut(&mut self, inst: Inst) -> &mut [Value] {
-        let fixed_args = self[inst].opcode().constraints().fixed_value_arguments();
+        let fixed_args = self[inst]
+            .opcode()
+            .constraints()
+            .fixed_value_arguments();
         &mut self.inst_args_mut(inst)[fixed_args..]
     }
 
@@ -444,8 +456,8 @@ impl DataFlowGraph {
         // Update the second_result pointer in `inst`.
         if head.is_some() {
             *self.insts[inst]
-                .second_result_mut()
-                .expect("instruction format doesn't allow multiple results") = head.into();
+                 .second_result_mut()
+                 .expect("instruction format doesn't allow multiple results") = head.into();
         }
         *self.insts[inst].first_type_mut() = first_type.unwrap_or_default();
 
@@ -505,7 +517,12 @@ impl DataFlowGraph {
                 (inst, 1)
             }
             ExpandedValue::Table(idx) => {
-                if let ValueData::Inst { num, inst, ref mut next, .. } = self.extended_values[idx] {
+                if let ValueData::Inst {
+                           num,
+                           inst,
+                           ref mut next,
+                           ..
+                       } = self.extended_values[idx] {
                     assert!(next.is_none(), "last_res is not the last result");
                     *next = res.into();
                     assert!(num < u16::MAX, "Too many arguments to EBB");
@@ -518,8 +535,12 @@ impl DataFlowGraph {
 
         // Now update `res` itself.
         if let ExpandedValue::Table(idx) = res.expand() {
-            if let ValueData::Inst { ref mut num, ref mut inst, ref mut next, .. } =
-                self.extended_values[idx] {
+            if let ValueData::Inst {
+                       ref mut num,
+                       ref mut inst,
+                       ref mut next,
+                       ..
+                   } = self.extended_values[idx] {
                 *num = res_num;
                 *inst = res_inst;
                 *next = None.into();
@@ -565,7 +586,8 @@ impl DataFlowGraph {
     ///
     /// Returns the new `Inst` reference where the original instruction has been moved.
     pub fn redefine_first_value(&mut self, pos: &mut Cursor) -> Inst {
-        let orig = pos.current_inst().expect("Cursor must point at an instruction");
+        let orig = pos.current_inst()
+            .expect("Cursor must point at an instruction");
         let data = self[orig].clone();
         // After cloning, any secondary values are attached to both copies. Don't do that, we only
         // want them on the new clone.
@@ -630,12 +652,13 @@ impl DataFlowGraph {
         }
 
         // Not a fixed result, try to extract a return type from the call signature.
-        self.call_signature(inst).and_then(|sigref| {
-                                               self.signatures[sigref]
-                                                   .return_types
-                                                   .get(result_idx - fixed_results)
-                                                   .map(|&arg| arg.value_type)
-                                           })
+        self.call_signature(inst)
+            .and_then(|sigref| {
+                          self.signatures[sigref]
+                              .return_types
+                              .get(result_idx - fixed_results)
+                              .map(|&arg| arg.value_type)
+                      })
     }
 }
 
@@ -815,8 +838,12 @@ impl DataFlowGraph {
         // Now update `arg` itself.
         let arg_ebb = ebb;
         if let ExpandedValue::Table(idx) = arg.expand() {
-            if let ValueData::Arg { ref mut num, ebb, ref mut next, .. } =
-                self.extended_values[idx] {
+            if let ValueData::Arg {
+                       ref mut num,
+                       ebb,
+                       ref mut next,
+                       ..
+                   } = self.extended_values[idx] {
                 *num = arg_num;
                 *next = None.into();
                 assert_eq!(arg_ebb, ebb, "{} should already belong to EBB", arg);
diff --git a/lib/cretonne/src/ir/entities.rs b/lib/cretonne/src/ir/entities.rs
index 42d109bf7a..876598d13a 100644
--- a/lib/cretonne/src/ir/entities.rs
+++ b/lib/cretonne/src/ir/entities.rs
@@ -286,14 +286,18 @@ mod tests {
         assert_eq!(Value::table_with_number(1).unwrap().to_string(), "vx1");
 
         assert_eq!(Value::direct_with_number(u32::MAX / 2), None);
-        assert_eq!(match Value::direct_with_number(u32::MAX / 2 - 1).unwrap().expand() {
+        assert_eq!(match Value::direct_with_number(u32::MAX / 2 - 1)
+                             .unwrap()
+                             .expand() {
                        ExpandedValue::Direct(i) => i.index() as u32,
                        _ => u32::MAX,
                    },
                    u32::MAX / 2 - 1);
 
         assert_eq!(Value::table_with_number(u32::MAX / 2), None);
-        assert_eq!(match Value::table_with_number(u32::MAX / 2 - 1).unwrap().expand() {
+        assert_eq!(match Value::table_with_number(u32::MAX / 2 - 1)
+                             .unwrap()
+                             .expand() {
                        ExpandedValue::Table(i) => i as u32,
                        _ => u32::MAX,
                    },
diff --git a/lib/cretonne/src/ir/extfunc.rs b/lib/cretonne/src/ir/extfunc.rs
index bc293d1169..43daaed192 100644
--- a/lib/cretonne/src/ir/extfunc.rs
+++ b/lib/cretonne/src/ir/extfunc.rs
@@ -221,7 +221,8 @@ mod tests {
         assert_eq!(sig.to_string(), "(i32)");
         sig.return_types.push(ArgumentType::new(F32));
         assert_eq!(sig.to_string(), "(i32) -> f32");
-        sig.argument_types.push(ArgumentType::new(I32.by(4).unwrap()));
+        sig.argument_types
+            .push(ArgumentType::new(I32.by(4).unwrap()));
         assert_eq!(sig.to_string(), "(i32, i32x4) -> f32");
         sig.return_types.push(ArgumentType::new(B8));
         assert_eq!(sig.to_string(), "(i32, i32x4) -> f32, b8");
diff --git a/lib/cretonne/src/ir/instructions.rs b/lib/cretonne/src/ir/instructions.rs
index d3ca0bc62f..1c292f473a 100644
--- a/lib/cretonne/src/ir/instructions.rs
+++ b/lib/cretonne/src/ir/instructions.rs
@@ -304,15 +304,21 @@ impl InstructionData {
     /// here.
     pub fn analyze_branch<'a>(&'a self, pool: &'a ValueListPool) -> BranchInfo<'a> {
         match self {
-            &InstructionData::Jump { destination, ref args, .. } => {
-                BranchInfo::SingleDest(destination, &args.as_slice(pool))
-            }
-            &InstructionData::Branch { destination, ref args, .. } => {
-                BranchInfo::SingleDest(destination, &args.as_slice(pool)[1..])
-            }
-            &InstructionData::BranchIcmp { destination, ref args, .. } => {
-                BranchInfo::SingleDest(destination, &args.as_slice(pool)[2..])
-            }
+            &InstructionData::Jump {
+                 destination,
+                 ref args,
+                 ..
+             } => BranchInfo::SingleDest(destination, &args.as_slice(pool)),
+            &InstructionData::Branch {
+                 destination,
+                 ref args,
+                 ..
+             } => BranchInfo::SingleDest(destination, &args.as_slice(pool)[1..]),
+            &InstructionData::BranchIcmp {
+                 destination,
+                 ref args,
+                 ..
+             } => BranchInfo::SingleDest(destination, &args.as_slice(pool)[2..]),
             &InstructionData::BranchTable { table, .. } => BranchInfo::Table(table),
             _ => BranchInfo::NotABranch,
         }
@@ -601,9 +607,21 @@ impl OperandConstraint {
             Same => Bound(ctrl_type),
             LaneOf => Bound(ctrl_type.lane_type()),
             AsBool => Bound(ctrl_type.as_bool()),
-            HalfWidth => Bound(ctrl_type.half_width().expect("invalid type for half_width")),
-            DoubleWidth => Bound(ctrl_type.double_width().expect("invalid type for double_width")),
-            HalfVector => Bound(ctrl_type.half_vector().expect("invalid type for half_vector")),
+            HalfWidth => {
+                Bound(ctrl_type
+                          .half_width()
+                          .expect("invalid type for half_width"))
+            }
+            DoubleWidth => {
+                Bound(ctrl_type
+                          .double_width()
+                          .expect("invalid type for double_width"))
+            }
+            HalfVector => {
+                Bound(ctrl_type
+                          .half_vector()
+                          .expect("invalid type for half_vector"))
+            }
             DoubleVector => Bound(ctrl_type.by(2).expect("invalid type for double_vector")),
         }
     }
diff --git a/lib/cretonne/src/ir/jumptable.rs b/lib/cretonne/src/ir/jumptable.rs
index e7f98a329d..dd9bc5c187 100644
--- a/lib/cretonne/src/ir/jumptable.rs
+++ b/lib/cretonne/src/ir/jumptable.rs
@@ -66,15 +66,14 @@ impl JumpTableData {
     ///
     /// This returns an iterator that skips any empty slots in the table.
     pub fn entries<'a>(&'a self) -> Entries {
-        Entries(self.table
-                    .iter()
-                    .cloned()
-                    .enumerate())
+        Entries(self.table.iter().cloned().enumerate())
     }
 
     /// Checks if any of the entries branch to `ebb`.
     pub fn branches_to(&self, ebb: Ebb) -> bool {
-        self.table.iter().any(|target_ebb| target_ebb.expand() == Some(ebb))
+        self.table
+            .iter()
+            .any(|target_ebb| target_ebb.expand() == Some(ebb))
     }
 
     /// Access the whole table as a mutable slice.
@@ -109,10 +108,7 @@ impl Display for JumpTableData {
             Some(first) => write!(fmt, "jump_table {}", first)?,
         }
 
-        for dest in self.table
-                .iter()
-                .skip(1)
-                .map(|e| e.expand()) {
+        for dest in self.table.iter().skip(1).map(|e| e.expand()) {
             match dest {
                 None => write!(fmt, ", 0")?,
                 Some(ebb) => write!(fmt, ", {}", ebb)?,
diff --git a/lib/cretonne/src/ir/layout.rs b/lib/cretonne/src/ir/layout.rs
index c34d6a0aba..4f5d2355b2 100644
--- a/lib/cretonne/src/ir/layout.rs
+++ b/lib/cretonne/src/ir/layout.rs
@@ -125,7 +125,10 @@ impl Layout {
     /// Get the last sequence number in `ebb`.
     fn last_ebb_seq(&self, ebb: Ebb) -> SequenceNumber {
         // Get the seq of the last instruction if it exists, otherwise use the EBB header seq.
-        self.ebbs[ebb].last_inst.map(|inst| self.insts[inst].seq).unwrap_or(self.ebbs[ebb].seq)
+        self.ebbs[ebb]
+            .last_inst
+            .map(|inst| self.insts[inst].seq)
+            .unwrap_or(self.ebbs[ebb].seq)
     }
 
     /// Assign a valid sequence number to `ebb` such that the numbers are still monotonic. This may
@@ -134,7 +137,10 @@ impl Layout {
         assert!(self.is_ebb_inserted(ebb));
 
         // Get the sequence number immediately before `ebb`, or 0.
-        let prev_seq = self.ebbs[ebb].prev.map(|prev_ebb| self.last_ebb_seq(prev_ebb)).unwrap_or(0);
+        let prev_seq = self.ebbs[ebb]
+            .prev
+            .map(|prev_ebb| self.last_ebb_seq(prev_ebb))
+            .unwrap_or(0);
 
         // Get the sequence number immediately following `ebb`.
         let next_seq = if let Some(inst) = self.ebbs[ebb].first_inst.expand() {
@@ -159,7 +165,8 @@ impl Layout {
     /// Assign a valid sequence number to `inst` such that the numbers are still monotonic. This may
     /// require renumbering.
     fn assign_inst_seq(&mut self, inst: Inst) {
-        let ebb = self.inst_ebb(inst).expect("inst must be inserted before assigning an seq");
+        let ebb = self.inst_ebb(inst)
+            .expect("inst must be inserted before assigning an seq");
 
         // Get the sequence number immediately before `inst`.
         let prev_seq = match self.insts[inst].prev.expand() {
@@ -436,8 +443,8 @@ impl Layout {
     /// Insert `inst` before the instruction `before` in the same EBB.
     pub fn insert_inst(&mut self, inst: Inst, before: Inst) {
         assert_eq!(self.inst_ebb(inst), None);
-        let ebb =
-            self.inst_ebb(before).expect("Instruction before insertion point not in the layout");
+        let ebb = self.inst_ebb(before)
+            .expect("Instruction before insertion point not in the layout");
         let after = self.insts[before].prev;
         {
             let inst_node = self.insts.ensure(inst);
@@ -485,8 +492,8 @@ impl Layout {
     ///     i4
     /// ```
     pub fn split_ebb(&mut self, new_ebb: Ebb, before: Inst) {
-        let old_ebb =
-            self.inst_ebb(before).expect("The `before` instruction must be in the layout");
+        let old_ebb = self.inst_ebb(before)
+            .expect("The `before` instruction must be in the layout");
         assert!(!self.is_ebb_inserted(new_ebb));
 
         // Insert new_ebb after old_ebb.
@@ -786,8 +793,9 @@ impl<'f> Cursor<'f> {
                     self.pos = At(next);
                     Some(next)
                 } else {
-                    self.pos =
-                        After(self.layout.inst_ebb(inst).expect("current instruction removed?"));
+                    self.pos = After(self.layout
+                                         .inst_ebb(inst)
+                                         .expect("current instruction removed?"));
                     None
                 }
             }
@@ -837,8 +845,9 @@ impl<'f> Cursor<'f> {
                     self.pos = At(prev);
                     Some(prev)
                 } else {
-                    self.pos =
-                        Before(self.layout.inst_ebb(inst).expect("current instruction removed?"));
+                    self.pos = Before(self.layout
+                                          .inst_ebb(inst)
+                                          .expect("current instruction removed?"));
                     None
                 }
             }
diff --git a/lib/cretonne/src/ir/types.rs b/lib/cretonne/src/ir/types.rs
index 1321636add..550f25804b 100644
--- a/lib/cretonne/src/ir/types.rs
+++ b/lib/cretonne/src/ir/types.rs
@@ -348,12 +348,7 @@ mod tests {
         assert_eq!(big.bits(), 64 * 256);
 
         assert_eq!(big.half_vector().unwrap().to_string(), "f64x128");
-        assert_eq!(B1.by(2)
-                       .unwrap()
-                       .half_vector()
-                       .unwrap()
-                       .to_string(),
-                   "b1");
+        assert_eq!(B1.by(2).unwrap().half_vector().unwrap().to_string(), "b1");
         assert_eq!(I32.half_vector(), None);
         assert_eq!(VOID.half_vector(), None);
 
@@ -383,12 +378,7 @@ mod tests {
         assert_eq!(B1.by(8).unwrap().to_string(), "b1x8");
         assert_eq!(B8.by(1).unwrap().to_string(), "b8");
         assert_eq!(B16.by(256).unwrap().to_string(), "b16x256");
-        assert_eq!(B32.by(4)
-                       .unwrap()
-                       .by(2)
-                       .unwrap()
-                       .to_string(),
-                   "b32x8");
+        assert_eq!(B32.by(4).unwrap().by(2).unwrap().to_string(), "b32x8");
         assert_eq!(B64.by(8).unwrap().to_string(), "b64x8");
         assert_eq!(I8.by(64).unwrap().to_string(), "i8x64");
         assert_eq!(F64.by(2).unwrap().to_string(), "f64x2");
diff --git a/lib/cretonne/src/isa/enc_tables.rs b/lib/cretonne/src/isa/enc_tables.rs
index 71a3eba2e0..cfb0066b8c 100644
--- a/lib/cretonne/src/isa/enc_tables.rs
+++ b/lib/cretonne/src/isa/enc_tables.rs
@@ -90,13 +90,13 @@ pub fn lookup_enclist<OffT1, OffT2>(ctrl_typevar: Type,
                         Legalize::Expand
                     })
         .and_then(|l1idx| {
-            let l1ent = &level1_table[l1idx];
-            let l2off = l1ent.offset.into() as usize;
-            let l2tab = &level2_table[l2off..l2off + (1 << l1ent.log2len)];
-            probe(l2tab, opcode, opcode as usize)
-                .map(|l2idx| l2tab[l2idx].offset.into() as usize)
-                .ok_or(Legalize::Expand)
-        })
+                      let l1ent = &level1_table[l1idx];
+                      let l2off = l1ent.offset.into() as usize;
+                      let l2tab = &level2_table[l2off..l2off + (1 << l1ent.log2len)];
+                      probe(l2tab, opcode, opcode as usize)
+                          .map(|l2idx| l2tab[l2idx].offset.into() as usize)
+                          .ok_or(Legalize::Expand)
+                  })
 }
 
 /// Encoding list entry.
diff --git a/lib/cretonne/src/isa/riscv/binemit.rs b/lib/cretonne/src/isa/riscv/binemit.rs
index 057fac11aa..213d8a132e 100644
--- a/lib/cretonne/src/isa/riscv/binemit.rs
+++ b/lib/cretonne/src/isa/riscv/binemit.rs
@@ -235,7 +235,11 @@ fn put_sb<CS: CodeSink + ?Sized>(bits: u16, rs1: RegUnit, rs2: RegUnit, sink: &m
 }
 
 fn recipe_sb<CS: CodeSink + ?Sized>(func: &Function, inst: Inst, sink: &mut CS) {
-    if let InstructionData::BranchIcmp { destination, ref args, .. } = func.dfg[inst] {
+    if let InstructionData::BranchIcmp {
+               destination,
+               ref args,
+               ..
+           } = func.dfg[inst] {
         let args = &args.as_slice(&func.dfg.value_lists)[0..2];
         sink.reloc_ebb(RelocKind::Branch.into(), destination);
         put_sb(func.encodings[inst].bits(),
@@ -248,7 +252,11 @@ fn recipe_sb<CS: CodeSink + ?Sized>(func: &Function, inst: Inst, sink: &mut CS)
 }
 
 fn recipe_sbzero<CS: CodeSink + ?Sized>(func: &Function, inst: Inst, sink: &mut CS) {
-    if let InstructionData::Branch { destination, ref args, .. } = func.dfg[inst] {
+    if let InstructionData::Branch {
+               destination,
+               ref args,
+               ..
+           } = func.dfg[inst] {
         let args = &args.as_slice(&func.dfg.value_lists)[0..1];
         sink.reloc_ebb(RelocKind::Branch.into(), destination);
         put_sb(func.encodings[inst].bits(),
diff --git a/lib/cretonne/src/legalizer/boundary.rs b/lib/cretonne/src/legalizer/boundary.rs
index 2e3766057d..19e06b7ba4 100644
--- a/lib/cretonne/src/legalizer/boundary.rs
+++ b/lib/cretonne/src/legalizer/boundary.rs
@@ -107,7 +107,8 @@ fn legalize_inst_results<ResType>(dfg: &mut DataFlowGraph,
                                   -> Inst
     where ResType: FnMut(&DataFlowGraph, usize) -> ArgumentType
 {
-    let mut call = pos.current_inst().expect("Cursor must point to a call instruction");
+    let mut call = pos.current_inst()
+        .expect("Cursor must point to a call instruction");
 
     // We theoretically allow for call instructions that return a number of fixed results before
     // the call return values. In practice, it doesn't happen.
@@ -364,10 +365,13 @@ fn legalize_inst_arguments<ArgType>(dfg: &mut DataFlowGraph,
                                     mut get_abi_type: ArgType)
     where ArgType: FnMut(&DataFlowGraph, usize) -> ArgumentType
 {
-    let inst = pos.current_inst().expect("Cursor must point to a call instruction");
+    let inst = pos.current_inst()
+        .expect("Cursor must point to a call instruction");
 
     // Lift the value list out of the call instruction so we modify it.
-    let mut vlist = dfg[inst].take_value_list().expect("Call must have a value list");
+    let mut vlist = dfg[inst]
+        .take_value_list()
+        .expect("Call must have a value list");
 
     // The value list contains all arguments to the instruction, including the callee on an
     // indirect call which isn't part of the call arguments that must match the ABI signature.
@@ -405,7 +409,9 @@ fn legalize_inst_arguments<ArgType>(dfg: &mut DataFlowGraph,
 
     let mut abi_arg = 0;
     for old_arg in 0..have_args {
-        let old_value = vlist.get(old_arg_offset + old_arg, &dfg.value_lists).unwrap();
+        let old_value = vlist
+            .get(old_arg_offset + old_arg, &dfg.value_lists)
+            .unwrap();
         let mut put_arg = |dfg: &mut DataFlowGraph, arg| {
             let abi_type = get_abi_type(dfg, abi_arg);
             if dfg.value_type(arg) == abi_type.value_type {
@@ -435,7 +441,8 @@ fn legalize_inst_arguments<ArgType>(dfg: &mut DataFlowGraph,
 ///
 /// Returns `true` if any instructions were inserted.
 pub fn handle_call_abi(dfg: &mut DataFlowGraph, cfg: &ControlFlowGraph, pos: &mut Cursor) -> bool {
-    let mut inst = pos.current_inst().expect("Cursor must point to a call instruction");
+    let mut inst = pos.current_inst()
+        .expect("Cursor must point to a call instruction");
 
     // Start by checking if the argument types already match the signature.
     let sig_ref = match check_call_signature(dfg, inst) {
@@ -475,7 +482,8 @@ pub fn handle_return_abi(dfg: &mut DataFlowGraph,
                          pos: &mut Cursor,
                          sig: &Signature)
                          -> bool {
-    let inst = pos.current_inst().expect("Cursor must point to a return instruction");
+    let inst = pos.current_inst()
+        .expect("Cursor must point to a return instruction");
 
     // Check if the returned types already match the signature.
     if check_return_signature(dfg, inst, sig) {
diff --git a/lib/cretonne/src/legalizer/split.rs b/lib/cretonne/src/legalizer/split.rs
index 3dda54abe7..d1f55a6266 100644
--- a/lib/cretonne/src/legalizer/split.rs
+++ b/lib/cretonne/src/legalizer/split.rs
@@ -125,7 +125,9 @@ fn split_any(dfg: &mut DataFlowGraph,
                     "Predecessor not a branch: {}",
                     dfg.display_inst(inst));
             let fixed_args = branch_opc.constraints().fixed_value_arguments();
-            let mut args = dfg[inst].take_value_list().expect("Branches must have value lists.");
+            let mut args = dfg[inst]
+                .take_value_list()
+                .expect("Branches must have value lists.");
             let num_args = args.len(&dfg.value_lists);
             // Get the old value passed to the EBB argument we're repairing.
             let old_arg = args.get(fixed_args + repair.num, &dfg.value_lists)
@@ -142,12 +144,14 @@ fn split_any(dfg: &mut DataFlowGraph,
             let (lo, hi) = split_value(dfg, pos, old_arg, repair.concat, &mut repairs);
 
             // The `lo` part replaces the original argument.
-            *args.get_mut(fixed_args + repair.num, &mut dfg.value_lists).unwrap() = lo;
+            *args.get_mut(fixed_args + repair.num, &mut dfg.value_lists)
+                 .unwrap() = lo;
 
             // The `hi` part goes at the end. Since multiple repairs may have been scheduled to the
             // same EBB, there could be multiple arguments missing.
             if num_args > fixed_args + repair.hi_num {
-                *args.get_mut(fixed_args + repair.hi_num, &mut dfg.value_lists).unwrap() = hi;
+                *args.get_mut(fixed_args + repair.hi_num, &mut dfg.value_lists)
+                     .unwrap() = hi;
             } else {
                 // We need to append one or more arguments. If we're adding more than one argument,
                 // there must be pending repairs on the stack that will fill in the correct values
diff --git a/lib/cretonne/src/partition_slice.rs b/lib/cretonne/src/partition_slice.rs
index 0986613040..9626b5fd37 100644
--- a/lib/cretonne/src/partition_slice.rs
+++ b/lib/cretonne/src/partition_slice.rs
@@ -35,10 +35,7 @@ mod tests {
 
     fn check(x: &[u32], want: &[u32]) {
         assert_eq!(x.len(), want.len());
-        let want_count = want.iter()
-            .cloned()
-            .filter(|&x| x % 10 == 0)
-            .count();
+        let want_count = want.iter().cloned().filter(|&x| x % 10 == 0).count();
         let mut v = Vec::new();
         v.extend(x.iter().cloned());
         let count = partition_slice(&mut v[..], |&x| x % 10 == 0);
diff --git a/lib/cretonne/src/regalloc/coloring.rs b/lib/cretonne/src/regalloc/coloring.rs
index 9bc10c30b3..b8c08bd278 100644
--- a/lib/cretonne/src/regalloc/coloring.rs
+++ b/lib/cretonne/src/regalloc/coloring.rs
@@ -232,7 +232,9 @@ impl<'a> Context<'a> {
             if let Affinity::Reg(rc_index) = lv.affinity {
                 let regclass = self.reginfo.rc(rc_index);
                 // TODO: Fall back to a top-level super-class. Sub-classes are only hints.
-                let regunit = regs.iter(regclass).next().expect("Out of registers for arguments");
+                let regunit = regs.iter(regclass)
+                    .next()
+                    .expect("Out of registers for arguments");
                 regs.take(regclass, regunit);
                 *locations.ensure(lv.value) = ValueLoc::Reg(regunit);
             }
diff --git a/lib/cretonne/src/regalloc/context.rs b/lib/cretonne/src/regalloc/context.rs
index 195c480372..2c59ab9797 100644
--- a/lib/cretonne/src/regalloc/context.rs
+++ b/lib/cretonne/src/regalloc/context.rs
@@ -52,6 +52,7 @@ impl Context {
         // TODO: Second pass: Spilling.
 
         // Third pass: Reload and coloring.
-        self.coloring.run(isa, func, domtree, &mut self.liveness, &mut self.tracker);
+        self.coloring
+            .run(isa, func, domtree, &mut self.liveness, &mut self.tracker);
     }
 }
diff --git a/lib/cretonne/src/regalloc/live_value_tracker.rs b/lib/cretonne/src/regalloc/live_value_tracker.rs
index 19ed62e8fb..75b18ef019 100644
--- a/lib/cretonne/src/regalloc/live_value_tracker.rs
+++ b/lib/cretonne/src/regalloc/live_value_tracker.rs
@@ -68,11 +68,12 @@ impl LiveValueVec {
 
     /// Add a new live value to `values`.
     fn push(&mut self, value: Value, endpoint: Inst, affinity: Affinity) {
-        self.values.push(LiveValue {
-                             value: value,
-                             endpoint: endpoint,
-                             affinity: affinity,
-                         });
+        self.values
+            .push(LiveValue {
+                      value: value,
+                      endpoint: endpoint,
+                      affinity: affinity,
+                  });
     }
 
     /// Remove all elements.
@@ -163,11 +164,14 @@ impl LiveValueTracker {
             // If the immediate dominator exits, we must have a stored list for it. This is a
             // requirement to the order EBBs are visited: All dominators must have been processed
             // before the current EBB.
-            let idom_live_list =
-                self.idom_sets.get(&idom).expect("No stored live set for dominator");
+            let idom_live_list = self.idom_sets
+                .get(&idom)
+                .expect("No stored live set for dominator");
             // Get just the values that are live-in to `ebb`.
             for &value in idom_live_list.as_slice(&self.idom_pool) {
-                let lr = liveness.get(value).expect("Immediate dominator value has no live range");
+                let lr = liveness
+                    .get(value)
+                    .expect("Immediate dominator value has no live range");
 
                 // Check if this value is live-in here.
                 if let Some(endpoint) = lr.livein_local_end(ebb, program_order) {
@@ -179,7 +183,9 @@ impl LiveValueTracker {
         // Now add all the live arguments to `ebb`.
         let first_arg = self.live.values.len();
         for value in dfg.ebb_args(ebb) {
-            let lr = liveness.get(value).expect("EBB argument value has no live range");
+            let lr = liveness
+                .get(value)
+                .expect("EBB argument value has no live range");
             assert_eq!(lr.def(), ebb.into());
             match lr.def_local_end().into() {
                 ExpandedProgramPoint::Inst(endpoint) => {
@@ -259,16 +265,15 @@ impl LiveValueTracker {
 
     /// Save the current set of live values so it is associated with `idom`.
     fn save_idom_live_set(&mut self, idom: Inst) {
-        let values = self.live
-            .values
-            .iter()
-            .map(|lv| lv.value);
+        let values = self.live.values.iter().map(|lv| lv.value);
         let pool = &mut self.idom_pool;
         // If there already is a set saved for `idom`, just keep it.
-        self.idom_sets.entry(idom).or_insert_with(|| {
-                                                      let mut list = ValueList::default();
-                                                      list.extend(values, pool);
-                                                      list
-                                                  });
+        self.idom_sets
+            .entry(idom)
+            .or_insert_with(|| {
+                                let mut list = ValueList::default();
+                                list.extend(values, pool);
+                                list
+                            });
     }
 }
diff --git a/lib/cretonne/src/regalloc/liveness.rs b/lib/cretonne/src/regalloc/liveness.rs
index 40faff0591..3344c5b841 100644
--- a/lib/cretonne/src/regalloc/liveness.rs
+++ b/lib/cretonne/src/regalloc/liveness.rs
@@ -205,7 +205,8 @@ fn get_or_create<'a>(lrset: &'a mut LiveRangeSet,
                 def = inst.into();
                 // Initialize the affinity from the defining instruction's result constraints.
                 // Don't do this for call return values which are always tied to a single register.
-                affinity = recipe_constraints.get(func.encodings[inst].recipe())
+                affinity = recipe_constraints
+                    .get(func.encodings[inst].recipe())
                     .and_then(|rc| rc.outs.get(rnum))
                     .map(Affinity::new)
                     .unwrap_or_default();
@@ -315,7 +316,8 @@ impl Liveness {
                 let recipe = func.encodings[inst].recipe();
                 // Iterator of constraints, one per value operand.
                 // TODO: Should we fail here if the instruction doesn't have a valid encoding?
-                let mut operand_constraints = recipe_constraints.get(recipe)
+                let mut operand_constraints = recipe_constraints
+                    .get(recipe)
                     .map(|c| c.ins)
                     .unwrap_or(&[])
                     .iter();
diff --git a/lib/cretonne/src/regalloc/liverange.rs b/lib/cretonne/src/regalloc/liverange.rs
index 116ccce4aa..94c16cb9ae 100644
--- a/lib/cretonne/src/regalloc/liverange.rs
+++ b/lib/cretonne/src/regalloc/liverange.rs
@@ -221,14 +221,16 @@ impl LiveRange {
     /// Return `Ok(n)` if `liveins[n]` already contains `ebb`.
     /// Otherwise, return `Err(n)` with the index where such an interval should be inserted.
     fn find_ebb_interval<PO: ProgramOrder>(&self, ebb: Ebb, order: &PO) -> Result<usize, usize> {
-        self.liveins.binary_search_by(|intv| order.cmp(intv.begin, ebb)).or_else(|n| {
-            // The interval at `n-1` may cover `ebb`.
-            if n > 0 && order.cmp(self.liveins[n - 1].end, ebb) == Ordering::Greater {
-                Ok(n - 1)
-            } else {
-                Err(n)
-            }
-        })
+        self.liveins
+            .binary_search_by(|intv| order.cmp(intv.begin, ebb))
+            .or_else(|n| {
+                         // The interval at `n-1` may cover `ebb`.
+                         if n > 0 && order.cmp(self.liveins[n - 1].end, ebb) == Ordering::Greater {
+                             Ok(n - 1)
+                         } else {
+                             Err(n)
+                         }
+                     })
     }
 
     /// Extend the local interval for `ebb` so it reaches `to` which must belong to `ebb`.
@@ -307,11 +309,12 @@ impl LiveRange {
                     }
                     // Cannot coalesce; insert new interval
                     (false, false) => {
-                        self.liveins.insert(n,
-                                            Interval {
-                                                begin: ebb,
-                                                end: to,
-                                            });
+                        self.liveins
+                            .insert(n,
+                                    Interval {
+                                        begin: ebb,
+                                        end: to,
+                                    });
                     }
                 }
 
@@ -361,7 +364,9 @@ impl LiveRange {
     /// answer, but it is also possible that an even later program point is returned. So don't
     /// depend on the returned `Inst` to belong to `ebb`.
     pub fn livein_local_end<PO: ProgramOrder>(&self, ebb: Ebb, order: &PO) -> Option<Inst> {
-        self.find_ebb_interval(ebb, order).ok().map(|n| self.liveins[n].end)
+        self.find_ebb_interval(ebb, order)
+            .ok()
+            .map(|n| self.liveins[n].end)
     }
 }
 
diff --git a/lib/cretonne/src/verifier.rs b/lib/cretonne/src/verifier.rs
index 589f117e73..776755d4c4 100644
--- a/lib/cretonne/src/verifier.rs
+++ b/lib/cretonne/src/verifier.rs
@@ -177,8 +177,9 @@ impl<'a> Verifier<'a> {
 
         let fixed_results = inst_data.opcode().constraints().fixed_results();
         // var_results is 0 if we aren't a call instruction
-        let var_results =
-            dfg.call_signature(inst).map(|sig| dfg.signatures[sig].return_types.len()).unwrap_or(0);
+        let var_results = dfg.call_signature(inst)
+            .map(|sig| dfg.signatures[sig].return_types.len())
+            .unwrap_or(0);
         let total_results = fixed_results + var_results;
 
         if total_results == 0 {
@@ -218,9 +219,21 @@ impl<'a> Verifier<'a> {
             &MultiAry { ref args, .. } => {
                 self.verify_value_list(inst, args)?;
             }
-            &Jump { destination, ref args, .. } |
-            &Branch { destination, ref args, .. } |
-            &BranchIcmp { destination, ref args, .. } => {
+            &Jump {
+                 destination,
+                 ref args,
+                 ..
+             } |
+            &Branch {
+                 destination,
+                 ref args,
+                 ..
+             } |
+            &BranchIcmp {
+                 destination,
+                 ref args,
+                 ..
+             } => {
                 self.verify_ebb(inst, destination)?;
                 self.verify_value_list(inst, args)?;
             }
@@ -265,10 +278,7 @@ impl<'a> Verifier<'a> {
     }
 
     fn verify_sig_ref(&self, inst: Inst, s: SigRef) -> Result<()> {
-        if !self.func
-                .dfg
-                .signatures
-                .is_valid(s) {
+        if !self.func.dfg.signatures.is_valid(s) {
             err!(inst, "invalid signature reference {}", s)
         } else {
             Ok(())
@@ -276,10 +286,7 @@ impl<'a> Verifier<'a> {
     }
 
     fn verify_func_ref(&self, inst: Inst, f: FuncRef) -> Result<()> {
-        if !self.func
-                .dfg
-                .ext_funcs
-                .is_valid(f) {
+        if !self.func.dfg.ext_funcs.is_valid(f) {
             err!(inst, "invalid function reference {}", f)
         } else {
             Ok(())
@@ -326,7 +333,8 @@ impl<'a> Verifier<'a> {
                                 def_inst);
                 }
                 // Defining instruction dominates the instruction that uses the value.
-                if !self.domtree.dominates(def_inst, loc_inst, &self.func.layout) {
+                if !self.domtree
+                        .dominates(def_inst, loc_inst, &self.func.layout) {
                     return err!(loc_inst, "uses value from non-dominating {}", def_inst);
                 }
             }
@@ -343,7 +351,8 @@ impl<'a> Verifier<'a> {
                                 ebb);
                 }
                 // The defining EBB dominates the instruction using this value.
-                if !self.domtree.ebb_dominates(ebb, loc_inst, &self.func.layout) {
+                if !self.domtree
+                        .ebb_dominates(ebb, loc_inst, &self.func.layout) {
                     return err!(loc_inst, "uses value arg from non-dominating {}", ebb);
                 }
             }
@@ -378,10 +387,7 @@ impl<'a> Verifier<'a> {
                 return err!(ebb, "entry block arguments must match function signature");
             }
 
-            for (i, arg) in self.func
-                    .dfg
-                    .ebb_args(ebb)
-                    .enumerate() {
+            for (i, arg) in self.func.dfg.ebb_args(ebb).enumerate() {
                 let arg_type = self.func.dfg.value_type(arg);
                 if arg_type != expected_types[i].value_type {
                     return err!(ebb,
@@ -452,11 +458,7 @@ impl<'a> Verifier<'a> {
     fn typecheck_fixed_args(&self, inst: Inst, ctrl_type: Type) -> Result<()> {
         let constraints = self.func.dfg[inst].opcode().constraints();
 
-        for (i, &arg) in self.func
-                .dfg
-                .inst_fixed_args(inst)
-                .iter()
-                .enumerate() {
+        for (i, &arg) in self.func.dfg.inst_fixed_args(inst).iter().enumerate() {
             let arg_type = self.func.dfg.value_type(arg);
             match constraints.value_argument_constraint(i, ctrl_type) {
                 ResolvedConstraint::Bound(expected_type) => {
@@ -510,13 +512,17 @@ impl<'a> Verifier<'a> {
         match self.func.dfg[inst].analyze_call(&self.func.dfg.value_lists) {
             CallInfo::Direct(func_ref, _) => {
                 let sig_ref = self.func.dfg.ext_funcs[func_ref].signature;
-                let arg_types =
-                    self.func.dfg.signatures[sig_ref].argument_types.iter().map(|a| a.value_type);
+                let arg_types = self.func.dfg.signatures[sig_ref]
+                    .argument_types
+                    .iter()
+                    .map(|a| a.value_type);
                 self.typecheck_variable_args_iterator(inst, arg_types)?;
             }
             CallInfo::Indirect(sig_ref, _) => {
-                let arg_types =
-                    self.func.dfg.signatures[sig_ref].argument_types.iter().map(|a| a.value_type);
+                let arg_types = self.func.dfg.signatures[sig_ref]
+                    .argument_types
+                    .iter()
+                    .map(|a| a.value_type);
                 self.typecheck_variable_args_iterator(inst, arg_types)?;
             }
             CallInfo::NotACall => {}
@@ -673,10 +679,11 @@ mod tests {
         let mut func = Function::new();
         let ebb0 = func.dfg.make_ebb();
         func.layout.append_ebb(ebb0);
-        let nullary_with_bad_opcode = func.dfg.make_inst(InstructionData::Nullary {
-                                                             opcode: Opcode::Jump,
-                                                             ty: types::VOID,
-                                                         });
+        let nullary_with_bad_opcode = func.dfg
+            .make_inst(InstructionData::Nullary {
+                           opcode: Opcode::Jump,
+                           ty: types::VOID,
+                       });
         func.layout.append_inst(nullary_with_bad_opcode, ebb0);
         let verifier = Verifier::new(&func);
         assert_err_with_msg!(verifier.run(), "instruction format");
diff --git a/lib/cretonne/src/write.rs b/lib/cretonne/src/write.rs
index e1ac42ac09..e2cd0fe3f5 100644
--- a/lib/cretonne/src/write.rs
+++ b/lib/cretonne/src/write.rs
@@ -262,7 +262,11 @@ pub fn write_operands(w: &mut Write, dfg: &DataFlowGraph, inst: Inst) -> Result
         IntCompare { cond, args, .. } => write!(w, " {}, {}, {}", cond, args[0], args[1]),
         IntCompareImm { cond, arg, imm, .. } => write!(w, " {}, {}, {}", cond, arg, imm),
         FloatCompare { cond, args, .. } => write!(w, " {}, {}, {}", cond, args[0], args[1]),
-        Jump { destination, ref args, .. } => {
+        Jump {
+            destination,
+            ref args,
+            ..
+        } => {
             if args.is_empty() {
                 write!(w, " {}", destination)
             } else {
@@ -272,7 +276,11 @@ pub fn write_operands(w: &mut Write, dfg: &DataFlowGraph, inst: Inst) -> Result
                        DisplayValues(args.as_slice(pool)))
             }
         }
-        Branch { destination, ref args, .. } => {
+        Branch {
+            destination,
+            ref args,
+            ..
+        } => {
             let args = args.as_slice(pool);
             write!(w, " {}, {}", args[0], destination)?;
             if args.len() > 1 {
@@ -280,7 +288,12 @@ pub fn write_operands(w: &mut Write, dfg: &DataFlowGraph, inst: Inst) -> Result
             }
             Ok(())
         }
-        BranchIcmp { cond, destination, ref args, .. } => {
+        BranchIcmp {
+            cond,
+            destination,
+            ref args,
+            ..
+        } => {
             let args = args.as_slice(pool);
             write!(w, " {}, {}, {}, {}", cond, args[0], args[1], destination)?;
             if args.len() > 2 {
diff --git a/lib/filecheck/src/checker.rs b/lib/filecheck/src/checker.rs
index c854f3b6b8..031a50d9e3 100644
--- a/lib/filecheck/src/checker.rs
+++ b/lib/filecheck/src/checker.rs
@@ -183,11 +183,13 @@ impl Checker {
                     continue;
                 }
                 Directive::Regex(ref var, ref rx) => {
-                    state.vars.insert(var.clone(),
-                                      VarDef {
-                                          value: Value::Regex(Cow::Borrowed(rx)),
-                                          offset: 0,
-                                      });
+                    state
+                        .vars
+                        .insert(var.clone(),
+                                VarDef {
+                                    value: Value::Regex(Cow::Borrowed(rx)),
+                                    offset: 0,
+                                });
                     continue;
                 }
             };
@@ -208,10 +210,14 @@ impl Checker {
                         state.recorder.directive(not_idx);
                         if let Some((s, e)) = rx.find(&text[not_begin..match_begin]) {
                             // Matched `not:` pattern.
-                            state.recorder.matched_not(rx.as_str(), (not_begin + s, not_begin + e));
+                            state
+                                .recorder
+                                .matched_not(rx.as_str(), (not_begin + s, not_begin + e));
                             return Ok(false);
                         } else {
-                            state.recorder.missed_not(rx.as_str(), (not_begin, match_begin));
+                            state
+                                .recorder
+                                .missed_not(rx.as_str(), (not_begin, match_begin));
                         }
                     }
                 }
@@ -410,9 +416,11 @@ mod tests {
                    Ok(true));
         assert_eq!(b.directive("regex: X = tommy").map_err(e2s),
                    Err("expected '=' after variable 'X' in regex: X = tommy".to_string()));
-        assert_eq!(b.directive("[arm]not:    patt $x $(y) here").map_err(e2s),
+        assert_eq!(b.directive("[arm]not:    patt $x $(y) here")
+                       .map_err(e2s),
                    Ok(true));
-        assert_eq!(b.directive("[x86]sameln: $x $(y=[^]]*) there").map_err(e2s),
+        assert_eq!(b.directive("[x86]sameln: $x $(y=[^]]*) there")
+                       .map_err(e2s),
                    Ok(true));
         // Windows line ending sneaking in.
         assert_eq!(b.directive("regex: Y=foo\r").map_err(e2s), Ok(true));
diff --git a/lib/filecheck/src/explain.rs b/lib/filecheck/src/explain.rs
index 04a6cd233e..49780321b5 100644
--- a/lib/filecheck/src/explain.rs
+++ b/lib/filecheck/src/explain.rs
@@ -119,7 +119,8 @@ impl<'a> Display for Explainer<'a> {
                      m.regex)?;
 
             // Emit any variable definitions.
-            if let Ok(found) = self.vardefs.binary_search_by_key(&m.directive, |v| v.directive) {
+            if let Ok(found) = self.vardefs
+                   .binary_search_by_key(&m.directive, |v| v.directive) {
                 let mut first = found;
                 while first > 0 && self.vardefs[first - 1].directive == m.directive {
                     first -= 1;
@@ -147,50 +148,55 @@ impl<'a> Recorder for Explainer<'a> {
     }
 
     fn matched_check(&mut self, regex: &str, matched: MatchRange) {
-        self.matches.push(Match {
-                              directive: self.directive,
-                              is_match: true,
-                              is_not: false,
-                              regex: regex.to_owned(),
-                              range: matched,
-                          });
+        self.matches
+            .push(Match {
+                      directive: self.directive,
+                      is_match: true,
+                      is_not: false,
+                      regex: regex.to_owned(),
+                      range: matched,
+                  });
     }
 
     fn matched_not(&mut self, regex: &str, matched: MatchRange) {
-        self.matches.push(Match {
-                              directive: self.directive,
-                              is_match: true,
-                              is_not: true,
-                              regex: regex.to_owned(),
-                              range: matched,
-                          });
+        self.matches
+            .push(Match {
+                      directive: self.directive,
+                      is_match: true,
+                      is_not: true,
+                      regex: regex.to_owned(),
+                      range: matched,
+                  });
     }
 
     fn missed_check(&mut self, regex: &str, searched: MatchRange) {
-        self.matches.push(Match {
-                              directive: self.directive,
-                              is_match: false,
-                              is_not: false,
-                              regex: regex.to_owned(),
-                              range: searched,
-                          });
+        self.matches
+            .push(Match {
+                      directive: self.directive,
+                      is_match: false,
+                      is_not: false,
+                      regex: regex.to_owned(),
+                      range: searched,
+                  });
     }
 
     fn missed_not(&mut self, regex: &str, searched: MatchRange) {
-        self.matches.push(Match {
-                              directive: self.directive,
-                              is_match: false,
-                              is_not: true,
-                              regex: regex.to_owned(),
-                              range: searched,
-                          });
+        self.matches
+            .push(Match {
+                      directive: self.directive,
+                      is_match: false,
+                      is_not: true,
+                      regex: regex.to_owned(),
+                      range: searched,
+                  });
     }
 
     fn defined_var(&mut self, varname: &str, value: &str) {
-        self.vardefs.push(VarDef {
-                              directive: self.directive,
-                              varname: varname.to_owned(),
-                              value: value.to_owned(),
-                          });
+        self.vardefs
+            .push(VarDef {
+                      directive: self.directive,
+                      varname: varname.to_owned(),
+                      value: value.to_owned(),
+                  });
     }
 }
diff --git a/lib/reader/src/parser.rs b/lib/reader/src/parser.rs
index e8d88dde89..ca98bd98f2 100644
--- a/lib/reader/src/parser.rs
+++ b/lib/reader/src/parser.rs
@@ -107,7 +107,8 @@ impl<'a> Context<'a> {
     // Get the index of a recipe name if it exists.
     fn find_recipe_index(&self, recipe_name: &str) -> Option<u16> {
         if let Some(unique_isa) = self.unique_isa {
-            unique_isa.recipe_names()
+            unique_isa
+                .recipe_names()
                 .iter()
                 .position(|&name| name == recipe_name)
                 .map(|idx| idx as u16)
@@ -118,17 +119,14 @@ impl<'a> Context<'a> {
 
     // Allocate a new stack slot and add a mapping number -> StackSlot.
     fn add_ss(&mut self, number: u32, data: StackSlotData, loc: &Location) -> Result<()> {
-        self.map.def_ss(number, self.function.stack_slots.push(data), loc)
+        self.map
+            .def_ss(number, self.function.stack_slots.push(data), loc)
     }
 
     // Allocate a new signature and add a mapping number -> SigRef.
     fn add_sig(&mut self, number: u32, data: Signature, loc: &Location) -> Result<()> {
-        self.map.def_sig(number,
-                         self.function
-                             .dfg
-                             .signatures
-                             .push(data),
-                         loc)
+        self.map
+            .def_sig(number, self.function.dfg.signatures.push(data), loc)
     }
 
     // Resolve a reference to a signature.
@@ -141,12 +139,8 @@ impl<'a> Context<'a> {
 
     // Allocate a new external function and add a mapping number -> FuncRef.
     fn add_fn(&mut self, number: u32, data: ExtFuncData, loc: &Location) -> Result<()> {
-        self.map.def_fn(number,
-                        self.function
-                            .dfg
-                            .ext_funcs
-                            .push(data),
-                        loc)
+        self.map
+            .def_fn(number, self.function.dfg.ext_funcs.push(data), loc)
     }
 
     // Resolve a reference to a function.
@@ -159,7 +153,8 @@ impl<'a> Context<'a> {
 
     // Allocate a new jump table and add a mapping number -> JumpTable.
     fn add_jt(&mut self, number: u32, data: JumpTableData, loc: &Location) -> Result<()> {
-        self.map.def_jt(number, self.function.jump_tables.push(data), loc)
+        self.map
+            .def_jt(number, self.function.jump_tables.push(data), loc)
     }
 
     // Resolve a reference to a jump table.
@@ -238,19 +233,34 @@ impl<'a> Context<'a> {
                     }
 
                     InstructionData::MultiAry { ref mut args, .. } => {
-                        self.map.rewrite_values(args.as_mut_slice(value_lists), loc)?;
+                        self.map
+                            .rewrite_values(args.as_mut_slice(value_lists), loc)?;
                     }
 
-                    InstructionData::Jump { ref mut destination, ref mut args, .. } |
-                    InstructionData::Branch { ref mut destination, ref mut args, .. } |
-                    InstructionData::BranchIcmp { ref mut destination, ref mut args, .. } => {
+                    InstructionData::Jump {
+                        ref mut destination,
+                        ref mut args,
+                        ..
+                    } |
+                    InstructionData::Branch {
+                        ref mut destination,
+                        ref mut args,
+                        ..
+                    } |
+                    InstructionData::BranchIcmp {
+                        ref mut destination,
+                        ref mut args,
+                        ..
+                    } => {
                         self.map.rewrite_ebb(destination, loc)?;
-                        self.map.rewrite_values(args.as_mut_slice(value_lists), loc)?;
+                        self.map
+                            .rewrite_values(args.as_mut_slice(value_lists), loc)?;
                     }
 
                     InstructionData::Call { ref mut args, .. } |
                     InstructionData::IndirectCall { ref mut args, .. } => {
-                        self.map.rewrite_values(args.as_mut_slice(value_lists), loc)?;
+                        self.map
+                            .rewrite_values(args.as_mut_slice(value_lists), loc)?;
                     }
                 }
             }
@@ -307,10 +317,11 @@ impl<'a> Parser<'a> {
                         Token::Comment(text) => {
                             // Gather comments, associate them with `comment_entity`.
                             if let Some(entity) = self.comment_entity {
-                                self.comments.push(Comment {
-                                                       entity: entity,
-                                                       text: text,
-                                                   });
+                                self.comments
+                                    .push(Comment {
+                                              entity: entity,
+                                              text: text,
+                                          });
                             }
                         }
                         _ => self.lookahead = Some(token),
@@ -464,7 +475,8 @@ impl<'a> Parser<'a> {
             self.consume();
             // Lexer just gives us raw text that looks like an integer.
             // Parse it as a u8 to check for overflow and other issues.
-            text.parse().map_err(|_| self.error("expected u8 decimal immediate"))
+            text.parse()
+                .map_err(|_| self.error("expected u8 decimal immediate"))
         } else {
             err!(self.loc, err_msg)
         }
@@ -477,7 +489,8 @@ impl<'a> Parser<'a> {
             self.consume();
             // Lexer just gives us raw text that looks like an integer.
             // Parse it as a u32 to check for overflow and other issues.
-            text.parse().map_err(|_| self.error("expected u32 decimal immediate"))
+            text.parse()
+                .map_err(|_| self.error("expected u32 decimal immediate"))
         } else {
             err!(self.loc, err_msg)
         }
@@ -714,7 +727,9 @@ impl<'a> Parser<'a> {
             sig.return_types = self.parse_argument_list(unique_isa)?;
         }
 
-        if sig.argument_types.iter().all(|a| a.location.is_assigned()) {
+        if sig.argument_types
+               .iter()
+               .all(|a| a.location.is_assigned()) {
             sig.compute_argument_bytes();
         }
 
@@ -816,35 +831,23 @@ impl<'a> Parser<'a> {
             match self.token() {
                 Some(Token::StackSlot(..)) => {
                     self.gather_comments(ctx.function.stack_slots.next_key());
-                    self.parse_stack_slot_decl().and_then(|(num, dat)| {
-                                                              ctx.add_ss(num, dat, &self.loc)
-                                                          })
+                    self.parse_stack_slot_decl()
+                        .and_then(|(num, dat)| ctx.add_ss(num, dat, &self.loc))
                 }
                 Some(Token::SigRef(..)) => {
-                    self.gather_comments(ctx.function
-                                             .dfg
-                                             .signatures
-                                             .next_key());
-                    self.parse_signature_decl(ctx.unique_isa).and_then(|(num, dat)| {
-                                                                           ctx.add_sig(num,
-                                                                                       dat,
-                                                                                       &self.loc)
-                                                                       })
+                    self.gather_comments(ctx.function.dfg.signatures.next_key());
+                    self.parse_signature_decl(ctx.unique_isa)
+                        .and_then(|(num, dat)| ctx.add_sig(num, dat, &self.loc))
                 }
                 Some(Token::FuncRef(..)) => {
-                    self.gather_comments(ctx.function
-                                             .dfg
-                                             .ext_funcs
-                                             .next_key());
-                    self.parse_function_decl(ctx).and_then(|(num, dat)| {
-                                                               ctx.add_fn(num, dat, &self.loc)
-                                                           })
+                    self.gather_comments(ctx.function.dfg.ext_funcs.next_key());
+                    self.parse_function_decl(ctx)
+                        .and_then(|(num, dat)| ctx.add_fn(num, dat, &self.loc))
                 }
                 Some(Token::JumpTable(..)) => {
                     self.gather_comments(ctx.function.jump_tables.next_key());
-                    self.parse_jump_table_decl().and_then(|(num, dat)| {
-                                                              ctx.add_jt(num, dat, &self.loc)
-                                                          })
+                    self.parse_jump_table_decl()
+                        .and_then(|(num, dat)| ctx.add_jt(num, dat, &self.loc))
                 }
                 // More to come..
                 _ => return Ok(()),
@@ -861,7 +864,8 @@ impl<'a> Parser<'a> {
         self.match_identifier("stack_slot", "expected 'stack_slot'")?;
 
         // stack-slot-decl ::= StackSlot(ss) "=" "stack_slot" * Bytes {"," stack-slot-flag}
-        let bytes: i64 = self.match_imm64("expected byte-size in stack_slot decl")?.into();
+        let bytes: i64 = self.match_imm64("expected byte-size in stack_slot decl")?
+            .into();
         if bytes < 0 {
             return err!(self.loc, "negative stack slot size");
         }
@@ -903,11 +907,10 @@ impl<'a> Parser<'a> {
         let data = match self.token() {
             Some(Token::Identifier("function")) => {
                 let (loc, name, sig) = self.parse_function_spec(ctx.unique_isa)?;
-                let sigref = ctx.function
-                    .dfg
-                    .signatures
-                    .push(sig);
-                ctx.map.def_entity(sigref.into(), &loc).expect("duplicate SigRef entities created");
+                let sigref = ctx.function.dfg.signatures.push(sig);
+                ctx.map
+                    .def_entity(sigref.into(), &loc)
+                    .expect("duplicate SigRef entities created");
                 ExtFuncData {
                     name: name,
                     signature: sigref,
@@ -1224,7 +1227,9 @@ impl<'a> Parser<'a> {
         let inst = ctx.function.dfg.make_inst(inst_data);
         let num_results = ctx.function.dfg.make_inst_results(inst, ctrl_typevar);
         ctx.function.layout.append_inst(inst, ebb);
-        ctx.map.def_entity(inst.into(), &opcode_loc).expect("duplicate inst references created");
+        ctx.map
+            .def_entity(inst.into(), &opcode_loc)
+            .expect("duplicate inst references created");
 
         if let Some(encoding) = encoding {
             *ctx.function.encodings.ensure(inst) = encoding;
@@ -1282,18 +1287,21 @@ impl<'a> Parser<'a> {
                      inst_data: &InstructionData)
                      -> Result<Type> {
         let constraints = opcode.constraints();
-        let ctrl_type = match explicit_ctrl_type {
-            Some(t) => t,
-            None => {
-                if constraints.use_typevar_operand() {
-                    // This is an opcode that supports type inference, AND there was no explicit
-                    // type specified. Look up `ctrl_value` to see if it was defined already.
-                    // TBD: If it is defined in another block, the type should have been specified
-                    // explicitly. It is unfortunate that the correctness of IL depends on the
-                    // layout of the blocks.
-                    let ctrl_src_value = inst_data.typevar_operand(&ctx.function.dfg.value_lists)
-                        .expect("Constraints <-> Format inconsistency");
-                    ctx.function.dfg.value_type(match ctx.map.get_value(ctrl_src_value) {
+        let ctrl_type =
+            match explicit_ctrl_type {
+                Some(t) => t,
+                None => {
+                    if constraints.use_typevar_operand() {
+                        // This is an opcode that supports type inference, AND there was no
+                        // explicit type specified. Look up `ctrl_value` to see if it was defined
+                        // already.
+                        // TBD: If it is defined in another block, the type should have been
+                        // specified explicitly. It is unfortunate that the correctness of IL
+                        // depends on the layout of the blocks.
+                        let ctrl_src_value = inst_data
+                            .typevar_operand(&ctx.function.dfg.value_lists)
+                            .expect("Constraints <-> Format inconsistency");
+                        ctx.function.dfg.value_type(match ctx.map.get_value(ctrl_src_value) {
                         Some(v) => v,
                         None => {
                             if let Some(v) = ctx.aliases
@@ -1308,19 +1316,19 @@ impl<'a> Parser<'a> {
                             }
                         }
                     })
-                } else if constraints.is_polymorphic() {
-                    // This opcode does not support type inference, so the explicit type variable
-                    // is required.
-                    return err!(self.loc,
-                                "type variable required for polymorphic opcode, e.g. '{}.{}'",
-                                opcode,
-                                constraints.ctrl_typeset().unwrap().example());
-                } else {
-                    // This is a non-polymorphic opcode. No typevar needed.
-                    VOID
+                    } else if constraints.is_polymorphic() {
+                        // This opcode does not support type inference, so the explicit type
+                        // variable is required.
+                        return err!(self.loc,
+                                    "type variable required for polymorphic opcode, e.g. '{}.{}'",
+                                    opcode,
+                                    constraints.ctrl_typeset().unwrap().example());
+                    } else {
+                        // This is a non-polymorphic opcode. No typevar needed.
+                        VOID
+                    }
                 }
-            }
-        };
+            };
 
         // Verify that `ctrl_type` is valid for the controlling type variable. We don't want to
         // attempt deriving types from an incorrect basis.
@@ -1629,7 +1637,8 @@ impl<'a> Parser<'a> {
             InstructionFormat::BranchTable => {
                 let arg = self.match_value("expected SSA value operand")?;
                 self.match_token(Token::Comma, "expected ',' between operands")?;
-                let table = self.match_jt().and_then(|num| ctx.get_jt(num, &self.loc))?;
+                let table = self.match_jt()
+                    .and_then(|num| ctx.get_jt(num, &self.loc))?;
                 InstructionData::BranchTable {
                     opcode: opcode,
                     ty: VOID,
@@ -1679,7 +1688,8 @@ mod tests {
         assert_eq!(v4.to_string(), "v0");
         let vx3 = details.map.lookup_str("vx3").unwrap();
         assert_eq!(vx3.to_string(), "vx0");
-        let aliased_to = func.dfg.resolve_aliases(Value::table_with_number(0).unwrap());
+        let aliased_to = func.dfg
+            .resolve_aliases(Value::table_with_number(0).unwrap());
         assert_eq!(aliased_to.to_string(), "v0");
     }
 
@@ -1696,11 +1706,20 @@ mod tests {
                    "(i8 uext inreg, f32, f64) -> i32 sext, f64");
 
         // `void` is not recognized as a type by the lexer. It should not appear in files.
-        assert_eq!(Parser::new("() -> void").parse_signature(None).unwrap_err().to_string(),
+        assert_eq!(Parser::new("() -> void")
+                       .parse_signature(None)
+                       .unwrap_err()
+                       .to_string(),
                    "1: expected argument type");
-        assert_eq!(Parser::new("i8 -> i8").parse_signature(None).unwrap_err().to_string(),
+        assert_eq!(Parser::new("i8 -> i8")
+                       .parse_signature(None)
+                       .unwrap_err()
+                       .to_string(),
                    "1: expected function signature: ( args... )");
-        assert_eq!(Parser::new("(i8 -> i8").parse_signature(None).unwrap_err().to_string(),
+        assert_eq!(Parser::new("(i8 -> i8")
+                       .parse_signature(None)
+                       .unwrap_err()
+                       .to_string(),
                    "1: expected ')' after function arguments");
     }
 
diff --git a/lib/reader/src/testcommand.rs b/lib/reader/src/testcommand.rs
index 6d9dd9969e..a147487c77 100644
--- a/lib/reader/src/testcommand.rs
+++ b/lib/reader/src/testcommand.rs
@@ -40,7 +40,10 @@ impl<'a> TestCommand<'a> {
         let cmd = parts.next().unwrap_or("");
         TestCommand {
             command: cmd,
-            options: parts.filter(|s| !s.is_empty()).map(TestOption::new).collect(),
+            options: parts
+                .filter(|s| !s.is_empty())
+                .map(TestOption::new)
+                .collect(),
         }
     }
 }