1 files changed, 42 insertions, 47 deletions
diff --git a/lib/builtins/clzsi2.c b/lib/builtins/clzsi2.c
index 25b8ed2c4c240..3f9f27f413315 100644
--- a/lib/builtins/clzsi2.c
+++ b/lib/builtins/clzsi2.c
@@ -1,53 +1,48 @@
-/* ===-- clzsi2.c - Implement __clzsi2 -------------------------------------===
- *
- *               The LLVM Compiler Infrastructure
- *
- * This file is dual licensed under the MIT and the University of Illinois Open
- * Source Licenses. See LICENSE.TXT for details.
- *
- * ===----------------------------------------------------------------------===
- *
- * This file implements __clzsi2 for the compiler_rt library.
- *
- * ===----------------------------------------------------------------------===
- */
+//===-- clzsi2.c - Implement __clzsi2 -------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements __clzsi2 for the compiler_rt library.
+//
+//===----------------------------------------------------------------------===//
 
 #include "int_lib.h"
 
-/* Returns: the number of leading 0-bits */
+// Returns: the number of leading 0-bits
 
-/* Precondition: a != 0 */
+// Precondition: a != 0
 
-COMPILER_RT_ABI si_int
-__clzsi2(si_int a)
-{
-    su_int x = (su_int)a;
-    si_int t = ((x & 0xFFFF0000) == 0) << 4;  /* if (x is small) t = 16 else 0 */
-    x >>= 16 - t;      /* x = [0 - 0xFFFF] */
-    su_int r = t;       /* r = [0, 16] */
-    /* return r + clz(x) */
-    t = ((x & 0xFF00) == 0) << 3;
-    x >>= 8 - t;       /* x = [0 - 0xFF] */
-    r += t;            /* r = [0, 8, 16, 24] */
-    /* return r + clz(x) */
-    t = ((x & 0xF0) == 0) << 2;
-    x >>= 4 - t;       /* x = [0 - 0xF] */
-    r += t;            /* r = [0, 4, 8, 12, 16, 20, 24, 28] */
-    /* return r + clz(x) */
-    t = ((x & 0xC) == 0) << 1;
-    x >>= 2 - t;       /* x = [0 - 3] */
-    r += t;            /* r = [0 - 30] and is even */
-    /* return r + clz(x) */
-/*     switch (x)
- *     {
- *     case 0:
- *         return r + 2;
- *     case 1:
- *         return r + 1;
- *     case 2:
- *     case 3:
- *         return r;
- *     }
- */
-    return r + ((2 - x) & -((x & 2) == 0));
+COMPILER_RT_ABI si_int __clzsi2(si_int a) {
+  su_int x = (su_int)a;
+  si_int t = ((x & 0xFFFF0000) == 0) << 4; // if (x is small) t = 16 else 0
+  x >>= 16 - t;                            // x = [0 - 0xFFFF]
+  su_int r = t;                            // r = [0, 16]
+  // return r + clz(x)
+  t = ((x & 0xFF00) == 0) << 3;
+  x >>= 8 - t; // x = [0 - 0xFF]
+  r += t;      // r = [0, 8, 16, 24]
+  // return r + clz(x)
+  t = ((x & 0xF0) == 0) << 2;
+  x >>= 4 - t; // x = [0 - 0xF]
+  r += t;      // r = [0, 4, 8, 12, 16, 20, 24, 28]
+  // return r + clz(x)
+  t = ((x & 0xC) == 0) << 1;
+  x >>= 2 - t; // x = [0 - 3]
+  r += t;      // r = [0 - 30] and is even
+  // return r + clz(x)
+  //     switch (x)
+  //     {
+  //     case 0:
+  //         return r + 2;
+  //     case 1:
+  //         return r + 1;
+  //     case 2:
+  //     case 3:
+  //         return r;
+  //     }
+  return r + ((2 - x) & -((x & 2) == 0));
 }