Auto merge of rust-lang#66908 - Centril:rollup-26givp6, r=Centril

Rollup of 9 pull requests

Successful merges:

 - rust-lang#66612 (Initial implementation of or-pattern usefulness checking)
 - rust-lang#66705 (Atomic as_mut_ptr)
 - rust-lang#66759 (impl TrustedLen for vec::Drain)
 - rust-lang#66858 (Use LLVMAddAnalysisPasses instead of Rust's wrapper)
 - rust-lang#66870 (SimplifyArmIdentity only for locals with the same type)
 - rust-lang#66883 (rustc_typeck: gate AnonConst's generics on feature(const_generics).)
 - rust-lang#66889 (Make python-generated source files compatible with rustfmt)
 - rust-lang#66894 (Remove unneeded prelude imports in libcore tests)
 - rust-lang#66895 (Feature gating *declarations* => new crate `rustc_feature`)

Failed merges:

 - rust-lang#66905 (rustc_plugin: Remove some remaining plugin features)

r? @ghost

Cargo.lock

@@ -3199,6 +3199,7 @@ dependencies = [
  "rustc_data_structures",
  "rustc_error_codes",
  "rustc_errors",
+ "rustc_feature",
  "rustc_fs_util",
  "rustc_index",
  "rustc_macros",
@@ -3574,6 +3575,7 @@ dependencies = [
  "rustc_data_structures",
  "rustc_error_codes",
  "rustc_errors",
+ "rustc_feature",
  "rustc_interface",
  "rustc_lint",
  "rustc_metadata",
@@ -3607,6 +3609,15 @@ dependencies = [
  "unicode-width",
 ]
 
+[[package]]
+name = "rustc_feature"
+version = "0.0.0"
+dependencies = [
+ "lazy_static 1.3.0",
+ "rustc_data_structures",
+ "syntax_pos",
+]
+
 [[package]]
 name = "rustc_fs_util"
 version = "0.0.0"
@@ -3682,6 +3693,7 @@ dependencies = [
  "rustc",
  "rustc_data_structures",
  "rustc_error_codes",
+ "rustc_feature",
  "rustc_index",
  "rustc_target",
  "syntax",
@@ -3786,6 +3798,7 @@ dependencies = [
  "rustc_data_structures",
  "rustc_error_codes",
  "rustc_errors",
+ "rustc_feature",
  "rustc_lexer",
  "rustc_target",
  "smallvec 1.0.0",
@@ -3802,6 +3815,7 @@ dependencies = [
  "rustc_data_structures",
  "rustc_error_codes",
  "rustc_errors",
+ "rustc_feature",
  "rustc_index",
  "rustc_parse",
  "rustc_target",
@@ -3844,6 +3858,7 @@ dependencies = [
  "rustc_data_structures",
  "rustc_error_codes",
  "rustc_errors",
+ "rustc_feature",
  "rustc_metadata",
  "smallvec 1.0.0",
  "syntax",
@@ -4442,6 +4457,7 @@ dependencies = [
  "rustc_data_structures",
  "rustc_error_codes",
  "rustc_errors",
+ "rustc_feature",
  "rustc_index",
  "rustc_lexer",
  "rustc_macros",
@@ -4458,6 +4474,7 @@ dependencies = [
  "log",
  "rustc_data_structures",
  "rustc_errors",
+ "rustc_feature",
  "rustc_lexer",
  "rustc_parse",
  "serialize",
@@ -4475,6 +4492,7 @@ dependencies = [
  "rustc_data_structures",
  "rustc_error_codes",
  "rustc_errors",
+ "rustc_feature",
  "rustc_parse",
  "rustc_target",
  "smallvec 1.0.0",

src/etc/dec2flt_table.py

@@ -111,14 +111,18 @@ def print_proper_powers():
     print("pub const MIN_E: i16 = {};".format(MIN_E))
     print("pub const MAX_E: i16 = {};".format(MAX_E))
     print()
+    print("#[rustfmt::skip]")
     typ = "([u64; {0}], [i16; {0}])".format(len(powers))
-    print("pub const POWERS: ", typ, " = ([", sep='')
+    print("pub const POWERS: ", typ, " = (", sep='')
+    print("    [")
     for z in powers:
-        print("    0x{:x},".format(z.sig))
-    print("], [")
+        print("        0x{:x},".format(z.sig))
+    print("    ],")
+    print("    [")
     for z in powers:
-        print("    {},".format(z.exp))
-    print("]);")
+        print("        {},".format(z.exp))
+    print("    ],")
+    print(");")
 
 
 def print_short_powers(num_bits, significand_size):
@@ -127,6 +131,7 @@ def print_short_powers(num_bits, significand_size):
     max_e = int(ceil(log(max_sig, 5)))
     e_range = range(max_e)
     typ = "[f{}; {}]".format(num_bits, len(e_range))
+    print("#[rustfmt::skip]")
     print("pub const F", num_bits, "_SHORT_POWERS: ", typ, " = [", sep='')
     for e in e_range:
         print("    1e{},".format(e))

src/liballoc/vec.rs

@@ -2703,6 +2703,9 @@ impl<T> ExactSizeIterator for Drain<'_, T> {
     }
 }
 
+#[unstable(feature = "trusted_len", issue = "37572")]
+unsafe impl<T> TrustedLen for Drain<'_, T> {}
+
 #[stable(feature = "fused", since = "1.26.0")]
 impl<T> FusedIterator for Drain<'_, T> {}