Rollup merge of #94146 - est31:let_else, r=cjgillot

Adopt let else in more places

Continuation of #89933, #91018, #91481, #93046, #93590, #94011.

I have extended my clippy lint to also recognize tuple passing and match statements. The diff caused by fixing it is way above 1 thousand lines. Thus, I split it up into multiple pull requests to make reviewing easier. This is the biggest of these PRs and handles the changes outside of rustdoc, rustc_typeck, rustc_const_eval, rustc_trait_selection, which were handled in PRs #94139, #94142, #94143, #94144.

1 files changed, 2 insertions, 8 deletions

diff --git a/compiler/rustc_codegen_llvm/src/back/write.rs b/compiler/rustc_codegen_llvm/src/back/write.rs
index 384596dfff5..e60ad170434 100644
--- a/compiler/rustc_codegen_llvm/src/back/write.rs
+++ b/compiler/rustc_codegen_llvm/src/back/write.rs
@@ -826,20 +826,14 @@ pub(crate) unsafe fn codegen(
                 let input =
                     unsafe { slice::from_raw_parts(input_ptr as *const u8, input_len as usize) };
 
-                let input = match str::from_utf8(input) {
-                    Ok(s) => s,
-                    Err(_) => return 0,
-                };
+                let Ok(input) = str::from_utf8(input) else { return 0 };
 
                 let output = unsafe {
                     slice::from_raw_parts_mut(output_ptr as *mut u8, output_len as usize)
                 };
                 let mut cursor = io::Cursor::new(output);
 
-                let demangled = match rustc_demangle::try_demangle(input) {
-                    Ok(d) => d,
-                    Err(_) => return 0,
-                };
+                let Ok(demangled) = rustc_demangle::try_demangle(input) else { return 0 };
 
                 if write!(cursor, "{:#}", demangled).is_err() {
                     // Possible only if provided buffer is not big enough