diff --git a/compiler/rustc_span/src/span_encoding.rs b/compiler/rustc_span/src/span_encoding.rs
index be4a72896d761..f467a7bcc18fe 100644
--- a/compiler/rustc_span/src/span_encoding.rs
+++ b/compiler/rustc_span/src/span_encoding.rs
@@ -124,6 +124,7 @@ enum Fmt<'a> {
 }
 
 impl InlineCtxt {
+    #[inline]
     fn data(self) -> SpanData {
         let len = self.len as u32;
         debug_assert!(len <= MAX_LEN);
@@ -134,12 +135,14 @@ impl InlineCtxt {
             parent: None,
         }
     }
+    #[inline]
     fn to_span(self) -> Span {
         unsafe { transmute(self) }
     }
 }
 
 impl InlineParent {
+    #[inline]
     fn data(self) -> SpanData {
         let len = (self.len_with_tag & !PARENT_TAG) as u32;
         debug_assert!(len <= MAX_LEN);
@@ -150,33 +153,39 @@ impl InlineParent {
             parent: Some(LocalDefId { local_def_index: DefIndex::from_u32(self.parent as u32) }),
         }
     }
+    #[inline]
     fn to_span(self) -> Span {
         unsafe { transmute(self) }
     }
 }
 
 impl PartiallyInterned {
+    #[inline]
     fn data(self) -> SpanData {
         SpanData {
             ctxt: SyntaxContext::from_u32(self.ctxt as u32),
             ..with_span_interner(|interner| interner.spans[self.index as usize])
         }
     }
+    #[inline]
     fn to_span(self) -> Span {
         unsafe { transmute(self) }
     }
 }
 
 impl Interned {
+    #[inline]
     fn data(self) -> SpanData {
         with_span_interner(|interner| interner.spans[self.index as usize])
     }
+    #[inline]
     fn to_span(self) -> Span {
         unsafe { transmute(self) }
     }
 }
 
 impl Fmt<'_> {
+    #[inline]
     fn data(self) -> SpanData {
         match self {
             Fmt::InlineCtxt(span) => span.data(),
@@ -241,6 +250,7 @@ impl Span {
         }
     }
 
+    #[inline]
     fn fmt(&mut self) -> Fmt<'_> {
         if self.len_with_tag_or_marker != BASE_LEN_INTERNED_MARKER {
             if self.len_with_tag_or_marker & PARENT_TAG == 0 {
@@ -291,6 +301,7 @@ impl Span {
     // For optimization we are interested in cases in which the context is inline and the context
     // update doesn't change format. All non-inline or format changing scenarios require accessing
     // interner and can fall back to `Span::new`.
+    #[inline]
     pub fn update_ctxt(&mut self, update: impl FnOnce(SyntaxContext) -> SyntaxContext) {
         // FIXME(#125017): Update ctxt inline without touching interner when possible.
         let data = self.data();
@@ -299,6 +310,7 @@ impl Span {
 
     // Returns either syntactic context, if it can be retrieved without taking the interner lock,
     // or an index into the interner if it cannot.
+    #[inline]
     fn inline_ctxt(mut self) -> Result<SyntaxContext, usize> {
         match self.fmt() {
             Fmt::InlineCtxt(InlineCtxt { ctxt, .. })