Auto merge of #113843 - wesleywiser:replace_rustc_apfloat, r=pnkfelix

Replace in-tree `rustc_apfloat` with the new version of the crate

Replace the in-tree version of `rustc_apfloat` with the new version of the crate which has been correctly licensed. The new crate incorporates upstream changes from LLVM since the original port was done including many correctness fixes and has been extensively fuzz tested to validate correctness.

Fixes #100233
Fixes #102403
Fixes #113407
Fixes #113409
Fixes #55993
Fixes #93224
Closes #93225
Closes #109573

3 files changed, 2 insertions, 14 deletions

diff --git a/src/tools/miri/src/shims/foreign_items.rs b/src/tools/miri/src/shims/foreign_items.rs
index c753eadbbad..763fa9235d0 100644
--- a/src/tools/miri/src/shims/foreign_items.rs
+++ b/src/tools/miri/src/shims/foreign_items.rs
@@ -914,16 +914,6 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 let x = this.read_scalar(x)?.to_f64()?;
                 let exp = this.read_scalar(exp)?.to_i32()?;
 
-                // Saturating cast to i16. Even those are outside the valid exponent range so
-                // `scalbn` below will do its over/underflow handling.
-                let exp = if exp > i32::from(i16::MAX) {
-                    i16::MAX
-                } else if exp < i32::from(i16::MIN) {
-                    i16::MIN
-                } else {
-                    exp.try_into().unwrap()
-                };
-
                 let res = x.scalbn(exp);
                 this.write_scalar(Scalar::from_f64(res), dest)?;
             }
diff --git a/src/tools/tidy/src/deps.rs b/src/tools/tidy/src/deps.rs
index bfb967213e1..57cbfe68be4 100644
--- a/src/tools/tidy/src/deps.rs
+++ b/src/tools/tidy/src/deps.rs
@@ -46,6 +46,7 @@ const EXCEPTIONS: &[(&str, &str)] = &[
     ("instant", "BSD-3-Clause"),                             // rustc_driver/tracing-subscriber/parking_lot
     ("mdbook", "MPL-2.0"),                                   // mdbook
     ("openssl", "Apache-2.0"),                               // opt-dist
+    ("rustc_apfloat", "Apache-2.0 WITH LLVM-exception"),     // rustc (license is the same as LLVM uses)
     ("ryu", "Apache-2.0 OR BSL-1.0"),                        // cargo/... (because of serde)
     ("self_cell", "Apache-2.0"),                             // rustc (fluent translations)
     ("snap", "BSD-3-Clause"),                                // rustc
@@ -224,6 +225,7 @@ const PERMITTED_RUSTC_DEPENDENCIES: &[&str] = &[
     "rustc-hash",
     "rustc-rayon",
     "rustc-rayon-core",
+    "rustc_apfloat",
     "rustc_version",
     "rustix",
     "ruzstd", // via object in thorin-dwp
diff --git a/src/tools/tidy/src/style.rs b/src/tools/tidy/src/style.rs
index d0257d71697..11480e2be60 100644
--- a/src/tools/tidy/src/style.rs
+++ b/src/tools/tidy/src/style.rs
@@ -302,10 +302,6 @@ pub fn check(path: &Path, bad: &mut bool) {
                 return;
             }
         }
-        // apfloat shouldn't be changed because of license problems
-        if is_in(file, "compiler", "rustc_apfloat") {
-            return;
-        }
         let mut skip_cr = contains_ignore_directive(can_contain, &contents, "cr");
         let mut skip_undocumented_unsafe =
             contains_ignore_directive(can_contain, &contents, "undocumented-unsafe");