Remove unused return values from resume and cleanup_ret

Given that these instructions are diverging, not every codegen backend
may be able to produce a return value for them.

Author: bjorn3

compiler/rustc_codegen_gcc/src/builder.rs

@@ -1275,15 +1275,15 @@ impl<'a, 'gcc, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'gcc, 'tcx> {
         // TODO(antoyo)
     }
 
-    fn resume(&mut self, _exn: RValue<'gcc>) -> RValue<'gcc> {
+    fn resume(&mut self, _exn: RValue<'gcc>) {
         unimplemented!();
     }
 
     fn cleanup_pad(&mut self, _parent: Option<RValue<'gcc>>, _args: &[RValue<'gcc>]) -> Funclet {
         unimplemented!();
     }
 
-    fn cleanup_ret(&mut self, _funclet: &Funclet, _unwind: Option<Block<'gcc>>) -> RValue<'gcc> {
+    fn cleanup_ret(&mut self, _funclet: &Funclet, _unwind: Option<Block<'gcc>>) {
         unimplemented!();
     }
 

compiler/rustc_codegen_llvm/src/builder.rs

@@ -983,8 +983,10 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
         }
     }
 
-    fn resume(&mut self, exn: &'ll Value) -> &'ll Value {
-        unsafe { llvm::LLVMBuildResume(self.llbuilder, exn) }
+    fn resume(&mut self, exn: &'ll Value) {
+        unsafe {
+            llvm::LLVMBuildResume(self.llbuilder, exn);
+        }
     }
 
     fn cleanup_pad(&mut self, parent: Option<&'ll Value>, args: &[&'ll Value]) -> Funclet<'ll> {
@@ -1001,14 +1003,11 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
         Funclet::new(ret.expect("LLVM does not have support for cleanuppad"))
     }
 
-    fn cleanup_ret(
-        &mut self,
-        funclet: &Funclet<'ll>,
-        unwind: Option<&'ll BasicBlock>,
-    ) -> &'ll Value {
-        let ret =
-            unsafe { llvm::LLVMRustBuildCleanupRet(self.llbuilder, funclet.cleanuppad(), unwind) };
-        ret.expect("LLVM does not have support for cleanupret")
+    fn cleanup_ret(&mut self, funclet: &Funclet<'ll>, unwind: Option<&'ll BasicBlock>) {
+        unsafe {
+            llvm::LLVMRustBuildCleanupRet(self.llbuilder, funclet.cleanuppad(), unwind)
+                .expect("LLVM does not have support for cleanupret");
+        }
     }
 
     fn catch_pad(&mut self, parent: &'ll Value, args: &[&'ll Value]) -> Funclet<'ll> {

compiler/rustc_codegen_ssa/src/traits/builder.rs

@@ -431,15 +431,11 @@ pub trait BuilderMethods<'a, 'tcx>:
         num_clauses: usize,
     ) -> Self::Value;
     fn set_cleanup(&mut self, landing_pad: Self::Value);
-    fn resume(&mut self, exn: Self::Value) -> Self::Value;
+    fn resume(&mut self, exn: Self::Value);
 
     // These are used only by msvc
     fn cleanup_pad(&mut self, parent: Option<Self::Value>, args: &[Self::Value]) -> Self::Funclet;
-    fn cleanup_ret(
-        &mut self,
-        funclet: &Self::Funclet,
-        unwind: Option<Self::BasicBlock>,
-    ) -> Self::Value;
+    fn cleanup_ret(&mut self, funclet: &Self::Funclet, unwind: Option<Self::BasicBlock>);
     fn catch_pad(&mut self, parent: Self::Value, args: &[Self::Value]) -> Self::Funclet;
     fn catch_switch(
         &mut self,