From 0c843613423cdd6fdf8d8efe462bfc66640c14f2 Mon Sep 17 00:00:00 2001
From: Scott McMurray <scottmcm@users.noreply.github.com>
Date: Sat, 25 May 2024 15:58:26 -0700
Subject: [PATCH] Simplify the `unchecked_sh[lr]` ub-checks a bit

---
 library/core/src/num/int_macros.rs                          | 6 ++----
 library/core/src/num/uint_macros.rs                         | 6 ++----
 ...s.unchecked_shl_unsigned_smaller.Inline.panic-abort.diff | 2 +-
 ....unchecked_shl_unsigned_smaller.Inline.panic-unwind.diff | 2 +-
 ...ifts.unchecked_shr_signed_bigger.Inline.panic-abort.diff | 2 +-
 ...fts.unchecked_shr_signed_bigger.Inline.panic-unwind.diff | 2 +-
 6 files changed, 8 insertions(+), 12 deletions(-)

diff --git a/library/core/src/num/int_macros.rs b/library/core/src/num/int_macros.rs
index b8b4f581a7e63..c9c6e34eaad8e 100644
--- a/library/core/src/num/int_macros.rs
+++ b/library/core/src/num/int_macros.rs
@@ -1282,8 +1282,7 @@ macro_rules! int_impl {
                 concat!(stringify!($SelfT), "::unchecked_shl cannot overflow"),
                 (
                     rhs: u32 = rhs,
-                    bits: u32 = Self::BITS,
-                ) => rhs < bits,
+                ) => rhs < <$ActualT>::BITS,
             );
 
             // SAFETY: this is guaranteed to be safe by the caller.
@@ -1381,8 +1380,7 @@ macro_rules! int_impl {
                 concat!(stringify!($SelfT), "::unchecked_shr cannot overflow"),
                 (
                     rhs: u32 = rhs,
-                    bits: u32 = Self::BITS,
-                ) => rhs < bits,
+                ) => rhs < <$ActualT>::BITS,
             );
 
             // SAFETY: this is guaranteed to be safe by the caller.
diff --git a/library/core/src/num/uint_macros.rs b/library/core/src/num/uint_macros.rs
index 141d164de14a2..f70c34199acec 100644
--- a/library/core/src/num/uint_macros.rs
+++ b/library/core/src/num/uint_macros.rs
@@ -1369,8 +1369,7 @@ macro_rules! uint_impl {
                 concat!(stringify!($SelfT), "::unchecked_shl cannot overflow"),
                 (
                     rhs: u32 = rhs,
-                    bits: u32 = Self::BITS,
-                ) => rhs < bits,
+                ) => rhs < <$ActualT>::BITS,
             );
 
             // SAFETY: this is guaranteed to be safe by the caller.
@@ -1468,8 +1467,7 @@ macro_rules! uint_impl {
                 concat!(stringify!($SelfT), "::unchecked_shr cannot overflow"),
                 (
                     rhs: u32 = rhs,
-                    bits: u32 = Self::BITS,
-                ) => rhs < bits,
+                ) => rhs < <$ActualT>::BITS,
             );
 
             // SAFETY: this is guaranteed to be safe by the caller.
diff --git a/tests/mir-opt/inline/unchecked_shifts.unchecked_shl_unsigned_smaller.Inline.panic-abort.diff b/tests/mir-opt/inline/unchecked_shifts.unchecked_shl_unsigned_smaller.Inline.panic-abort.diff
index 652e24a5f8ec3..0d9d58316ea19 100644
--- a/tests/mir-opt/inline/unchecked_shifts.unchecked_shl_unsigned_smaller.Inline.panic-abort.diff
+++ b/tests/mir-opt/inline/unchecked_shifts.unchecked_shl_unsigned_smaller.Inline.panic-abort.diff
@@ -29,7 +29,7 @@
       }
   
       bb1: {
-+         _6 = core::num::<impl u16>::unchecked_shl::precondition_check(_4, const core::num::<impl u16>::BITS) -> [return: bb2, unwind unreachable];
++         _6 = core::num::<impl u16>::unchecked_shl::precondition_check(_4) -> [return: bb2, unwind unreachable];
 +     }
 + 
 +     bb2: {
diff --git a/tests/mir-opt/inline/unchecked_shifts.unchecked_shl_unsigned_smaller.Inline.panic-unwind.diff b/tests/mir-opt/inline/unchecked_shifts.unchecked_shl_unsigned_smaller.Inline.panic-unwind.diff
index dbcae605f7699..82f7eceaa1808 100644
--- a/tests/mir-opt/inline/unchecked_shifts.unchecked_shl_unsigned_smaller.Inline.panic-unwind.diff
+++ b/tests/mir-opt/inline/unchecked_shifts.unchecked_shl_unsigned_smaller.Inline.panic-unwind.diff
@@ -29,7 +29,7 @@
       }
   
       bb1: {
-+         _6 = core::num::<impl u16>::unchecked_shl::precondition_check(_4, const core::num::<impl u16>::BITS) -> [return: bb2, unwind unreachable];
++         _6 = core::num::<impl u16>::unchecked_shl::precondition_check(_4) -> [return: bb2, unwind unreachable];
 +     }
 + 
 +     bb2: {
diff --git a/tests/mir-opt/inline/unchecked_shifts.unchecked_shr_signed_bigger.Inline.panic-abort.diff b/tests/mir-opt/inline/unchecked_shifts.unchecked_shr_signed_bigger.Inline.panic-abort.diff
index 88d0621c2877c..6894b24669908 100644
--- a/tests/mir-opt/inline/unchecked_shifts.unchecked_shr_signed_bigger.Inline.panic-abort.diff
+++ b/tests/mir-opt/inline/unchecked_shifts.unchecked_shr_signed_bigger.Inline.panic-abort.diff
@@ -29,7 +29,7 @@
       }
   
       bb1: {
-+         _6 = core::num::<impl i64>::unchecked_shr::precondition_check(_4, const core::num::<impl i64>::BITS) -> [return: bb2, unwind unreachable];
++         _6 = core::num::<impl i64>::unchecked_shr::precondition_check(_4) -> [return: bb2, unwind unreachable];
 +     }
 + 
 +     bb2: {
diff --git a/tests/mir-opt/inline/unchecked_shifts.unchecked_shr_signed_bigger.Inline.panic-unwind.diff b/tests/mir-opt/inline/unchecked_shifts.unchecked_shr_signed_bigger.Inline.panic-unwind.diff
index 6d4c73cf576a6..070f4a1c5c835 100644
--- a/tests/mir-opt/inline/unchecked_shifts.unchecked_shr_signed_bigger.Inline.panic-unwind.diff
+++ b/tests/mir-opt/inline/unchecked_shifts.unchecked_shr_signed_bigger.Inline.panic-unwind.diff
@@ -29,7 +29,7 @@
       }
   
       bb1: {
-+         _6 = core::num::<impl i64>::unchecked_shr::precondition_check(_4, const core::num::<impl i64>::BITS) -> [return: bb2, unwind unreachable];
++         _6 = core::num::<impl i64>::unchecked_shr::precondition_check(_4) -> [return: bb2, unwind unreachable];
 +     }
 + 
 +     bb2: {