Fix even more clippy warnings

compiler/rustc_target/src/abi/call/mod.rs

@@ -474,31 +474,19 @@ impl<'a, Ty> ArgAbi<'a, Ty> {
     }
 
     pub fn is_indirect(&self) -> bool {
-        match self.mode {
-            PassMode::Indirect(..) => true,
-            _ => false,
-        }
+        matches!(self.mode, PassMode::Indirect(..))
     }
 
     pub fn is_sized_indirect(&self) -> bool {
-        match self.mode {
-            PassMode::Indirect(_, None) => true,
-            _ => false,
-        }
+        matches!(self.mode, PassMode::Indirect(_, None))
     }
 
     pub fn is_unsized_indirect(&self) -> bool {
-        match self.mode {
-            PassMode::Indirect(_, Some(_)) => true,
-            _ => false,
-        }
+        matches!(self.mode, PassMode::Indirect(_, Some(_)))
     }
 
     pub fn is_ignore(&self) -> bool {
-        match self.mode {
-            PassMode::Ignore => true,
-            _ => false,
-        }
+        matches!(self.mode, PassMode::Ignore)
     }
 }
 

compiler/rustc_target/src/abi/call/riscv.rs

@@ -333,10 +333,8 @@ where
     let mut avail_gprs = 8;
     let mut avail_fprs = 8;
 
-    if !fn_abi.ret.is_ignore() {
-        if classify_ret(cx, &mut fn_abi.ret, xlen, flen) {
-            avail_gprs -= 1;
-        }
+    if !fn_abi.ret.is_ignore() && classify_ret(cx, &mut fn_abi.ret, xlen, flen) {
+        avail_gprs -= 1;
     }
 
     for (i, arg) in fn_abi.args.iter_mut().enumerate() {

compiler/rustc_target/src/abi/call/wasm32.rs

@@ -24,10 +24,8 @@ where
     C: LayoutOf<Ty = Ty, TyAndLayout = TyAndLayout<'a, Ty>> + HasDataLayout,
 {
     ret.extend_integer_width_to(32);
-    if ret.layout.is_aggregate() {
-        if !unwrap_trivial_aggregate(cx, ret) {
-            ret.make_indirect();
-        }
+    if ret.layout.is_aggregate() && !unwrap_trivial_aggregate(cx, ret) {
+        ret.make_indirect();
     }
 }
 
@@ -37,10 +35,8 @@ where
     C: LayoutOf<Ty = Ty, TyAndLayout = TyAndLayout<'a, Ty>> + HasDataLayout,
 {
     arg.extend_integer_width_to(32);
-    if arg.layout.is_aggregate() {
-        if !unwrap_trivial_aggregate(cx, arg) {
-            arg.make_indirect_byval();
-        }
+    if arg.layout.is_aggregate() && !unwrap_trivial_aggregate(cx, arg) {
+        arg.make_indirect_byval();
     }
 }
 

compiler/rustc_target/src/abi/mod.rs

@@ -557,17 +557,11 @@ impl Primitive {
     }
 
     pub fn is_float(self) -> bool {
-        match self {
-            F32 | F64 => true,
-            _ => false,
-        }
+        matches!(self, F32 | F64)
     }
 
     pub fn is_int(self) -> bool {
-        match self {
-            Int(..) => true,
-            _ => false,
-        }
+        matches!(self, Int(..))
     }
 }
 
@@ -794,18 +788,12 @@ impl Abi {
 
     /// Returns `true` if this is an uninhabited type
     pub fn is_uninhabited(&self) -> bool {
-        match *self {
-            Abi::Uninhabited => true,
-            _ => false,
-        }
+        matches!(*self, Abi::Uninhabited)
     }
 
     /// Returns `true` is this is a scalar type
     pub fn is_scalar(&self) -> bool {
-        match *self {
-            Abi::Scalar(_) => true,
-            _ => false,
-        }
+        matches!(*self, Abi::Scalar(_))
     }
 }
 

compiler/rustc_target/src/asm/mod.rs

@@ -478,10 +478,7 @@ pub enum InlineAsmType {
 
 impl InlineAsmType {
     pub fn is_integer(self) -> bool {
-        match self {
-            Self::I8 | Self::I16 | Self::I32 | Self::I64 | Self::I128 => true,
-            _ => false,
-        }
+        matches!(self, Self::I8 | Self::I16 | Self::I32 | Self::I64 | Self::I128)
     }
 
     pub fn size(self) -> Size {