Use the unsigned integer types for bitwise intrinsics.

Exposing ctpop, ctlz, cttz and bswap as taking signed i8/i16/... is just
exposing the internal LLVM names pointlessly (LLVM doesn't have "signed
integers" or "unsigned integers", it just has sized integer types
with (un)signed *operations*).

These operations are semantically working with raw bytes, which the
unsigned types model better.

src/test/bench/sudoku.rs

@@ -16,7 +16,7 @@ use std::io;
 use std::io::stdio::StdReader;
 use std::io::BufferedReader;
 use std::os;
-use std::intrinsics::cttz16;
+use std::num::Bitwise;
 
 // Computes a single solution to a given 9x9 sudoku
 //
@@ -187,9 +187,7 @@ impl Colors {
         if (0u16 == val) {
             return 0u8;
         } else {
-            unsafe {
-                return cttz16(val as i16) as u8;
-            }
+            return val.trailing_zeros() as u8
         }
     }
 

src/test/run-pass/intrinsics-integer.rs

@@ -1,4 +1,3 @@
-
 // Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
@@ -13,24 +12,24 @@
 
 mod rusti {
     extern "rust-intrinsic" {
-        pub fn ctpop8(x: i8) -> i8;
-        pub fn ctpop16(x: i16) -> i16;
-        pub fn ctpop32(x: i32) -> i32;
-        pub fn ctpop64(x: i64) -> i64;
+        pub fn ctpop8(x: u8) -> u8;
+        pub fn ctpop16(x: u16) -> u16;
+        pub fn ctpop32(x: u32) -> u32;
+        pub fn ctpop64(x: u64) -> u64;
 
-        pub fn ctlz8(x: i8) -> i8;
-        pub fn ctlz16(x: i16) -> i16;
-        pub fn ctlz32(x: i32) -> i32;
-        pub fn ctlz64(x: i64) -> i64;
+        pub fn ctlz8(x: u8) -> u8;
+        pub fn ctlz16(x: u16) -> u16;
+        pub fn ctlz32(x: u32) -> u32;
+        pub fn ctlz64(x: u64) -> u64;
 
-        pub fn cttz8(x: i8) -> i8;
-        pub fn cttz16(x: i16) -> i16;
-        pub fn cttz32(x: i32) -> i32;
-        pub fn cttz64(x: i64) -> i64;
+        pub fn cttz8(x: u8) -> u8;
+        pub fn cttz16(x: u16) -> u16;
+        pub fn cttz32(x: u32) -> u32;
+        pub fn cttz64(x: u64) -> u64;
 
-        pub fn bswap16(x: i16) -> i16;
-        pub fn bswap32(x: i32) -> i32;
-        pub fn bswap64(x: i64) -> i64;
+        pub fn bswap16(x: u16) -> u16;
+        pub fn bswap32(x: u32) -> u32;
+        pub fn bswap64(x: u64) -> u64;
     }
 }
 
@@ -38,83 +37,83 @@ pub fn main() {
     unsafe {
         use rusti::*;
 
-        assert_eq!(ctpop8(0i8), 0i8);
-        assert_eq!(ctpop16(0i16), 0i16);
-        assert_eq!(ctpop32(0i32), 0i32);
-        assert_eq!(ctpop64(0i64), 0i64);
+        assert_eq!(ctpop8(0u8), 0u8);
+        assert_eq!(ctpop16(0u16), 0u16);
+        assert_eq!(ctpop32(0u32), 0u32);
+        assert_eq!(ctpop64(0u64), 0u64);
 
-        assert_eq!(ctpop8(1i8), 1i8);
-        assert_eq!(ctpop16(1i16), 1i16);
-        assert_eq!(ctpop32(1i32), 1i32);
-        assert_eq!(ctpop64(1i64), 1i64);
+        assert_eq!(ctpop8(1u8), 1u8);
+        assert_eq!(ctpop16(1u16), 1u16);
+        assert_eq!(ctpop32(1u32), 1u32);
+        assert_eq!(ctpop64(1u64), 1u64);
 
-        assert_eq!(ctpop8(10i8), 2i8);
-        assert_eq!(ctpop16(10i16), 2i16);
-        assert_eq!(ctpop32(10i32), 2i32);
-        assert_eq!(ctpop64(10i64), 2i64);
+        assert_eq!(ctpop8(10u8), 2u8);
+        assert_eq!(ctpop16(10u16), 2u16);
+        assert_eq!(ctpop32(10u32), 2u32);
+        assert_eq!(ctpop64(10u64), 2u64);
 
-        assert_eq!(ctpop8(100i8), 3i8);
-        assert_eq!(ctpop16(100i16), 3i16);
-        assert_eq!(ctpop32(100i32), 3i32);
-        assert_eq!(ctpop64(100i64), 3i64);
+        assert_eq!(ctpop8(100u8), 3u8);
+        assert_eq!(ctpop16(100u16), 3u16);
+        assert_eq!(ctpop32(100u32), 3u32);
+        assert_eq!(ctpop64(100u64), 3u64);
 
-        assert_eq!(ctpop8(-1i8), 8i8);
-        assert_eq!(ctpop16(-1i16), 16i16);
-        assert_eq!(ctpop32(-1i32), 32i32);
-        assert_eq!(ctpop64(-1i64), 64i64);
+        assert_eq!(ctpop8(-1u8), 8u8);
+        assert_eq!(ctpop16(-1u16), 16u16);
+        assert_eq!(ctpop32(-1u32), 32u32);
+        assert_eq!(ctpop64(-1u64), 64u64);
 
-        assert_eq!(ctlz8(0i8), 8i8);
-        assert_eq!(ctlz16(0i16), 16i16);
-        assert_eq!(ctlz32(0i32), 32i32);
-        assert_eq!(ctlz64(0i64), 64i64);
+        assert_eq!(ctlz8(0u8), 8u8);
+        assert_eq!(ctlz16(0u16), 16u16);
+        assert_eq!(ctlz32(0u32), 32u32);
+        assert_eq!(ctlz64(0u64), 64u64);
 
-        assert_eq!(ctlz8(1i8), 7i8);
-        assert_eq!(ctlz16(1i16), 15i16);
-        assert_eq!(ctlz32(1i32), 31i32);
-        assert_eq!(ctlz64(1i64), 63i64);
+        assert_eq!(ctlz8(1u8), 7u8);
+        assert_eq!(ctlz16(1u16), 15u16);
+        assert_eq!(ctlz32(1u32), 31u32);
+        assert_eq!(ctlz64(1u64), 63u64);
 
-        assert_eq!(ctlz8(10i8), 4i8);
-        assert_eq!(ctlz16(10i16), 12i16);
-        assert_eq!(ctlz32(10i32), 28i32);
-        assert_eq!(ctlz64(10i64), 60i64);
+        assert_eq!(ctlz8(10u8), 4u8);
+        assert_eq!(ctlz16(10u16), 12u16);
+        assert_eq!(ctlz32(10u32), 28u32);
+        assert_eq!(ctlz64(10u64), 60u64);
 
-        assert_eq!(ctlz8(100i8), 1i8);
-        assert_eq!(ctlz16(100i16), 9i16);
-        assert_eq!(ctlz32(100i32), 25i32);
-        assert_eq!(ctlz64(100i64), 57i64);
+        assert_eq!(ctlz8(100u8), 1u8);
+        assert_eq!(ctlz16(100u16), 9u16);
+        assert_eq!(ctlz32(100u32), 25u32);
+        assert_eq!(ctlz64(100u64), 57u64);
 
-        assert_eq!(cttz8(-1i8), 0i8);
-        assert_eq!(cttz16(-1i16), 0i16);
-        assert_eq!(cttz32(-1i32), 0i32);
-        assert_eq!(cttz64(-1i64), 0i64);
+        assert_eq!(cttz8(-1u8), 0u8);
+        assert_eq!(cttz16(-1u16), 0u16);
+        assert_eq!(cttz32(-1u32), 0u32);
+        assert_eq!(cttz64(-1u64), 0u64);
 
-        assert_eq!(cttz8(0i8), 8i8);
-        assert_eq!(cttz16(0i16), 16i16);
-        assert_eq!(cttz32(0i32), 32i32);
-        assert_eq!(cttz64(0i64), 64i64);
+        assert_eq!(cttz8(0u8), 8u8);
+        assert_eq!(cttz16(0u16), 16u16);
+        assert_eq!(cttz32(0u32), 32u32);
+        assert_eq!(cttz64(0u64), 64u64);
 
-        assert_eq!(cttz8(1i8), 0i8);
-        assert_eq!(cttz16(1i16), 0i16);
-        assert_eq!(cttz32(1i32), 0i32);
-        assert_eq!(cttz64(1i64), 0i64);
+        assert_eq!(cttz8(1u8), 0u8);
+        assert_eq!(cttz16(1u16), 0u16);
+        assert_eq!(cttz32(1u32), 0u32);
+        assert_eq!(cttz64(1u64), 0u64);
 
-        assert_eq!(cttz8(10i8), 1i8);
-        assert_eq!(cttz16(10i16), 1i16);
-        assert_eq!(cttz32(10i32), 1i32);
-        assert_eq!(cttz64(10i64), 1i64);
+        assert_eq!(cttz8(10u8), 1u8);
+        assert_eq!(cttz16(10u16), 1u16);
+        assert_eq!(cttz32(10u32), 1u32);
+        assert_eq!(cttz64(10u64), 1u64);
 
-        assert_eq!(cttz8(100i8), 2i8);
-        assert_eq!(cttz16(100i16), 2i16);
-        assert_eq!(cttz32(100i32), 2i32);
-        assert_eq!(cttz64(100i64), 2i64);
+        assert_eq!(cttz8(100u8), 2u8);
+        assert_eq!(cttz16(100u16), 2u16);
+        assert_eq!(cttz32(100u32), 2u32);
+        assert_eq!(cttz64(100u64), 2u64);
 
-        assert_eq!(cttz8(-1i8), 0i8);
-        assert_eq!(cttz16(-1i16), 0i16);
-        assert_eq!(cttz32(-1i32), 0i32);
-        assert_eq!(cttz64(-1i64), 0i64);
+        assert_eq!(cttz8(-1u8), 0u8);
+        assert_eq!(cttz16(-1u16), 0u16);
+        assert_eq!(cttz32(-1u32), 0u32);
+        assert_eq!(cttz64(-1u64), 0u64);
 
-        assert_eq!(bswap16(0x0A0Bi16), 0x0B0Ai16);
-        assert_eq!(bswap32(0x0ABBCC0Di32), 0x0DCCBB0Ai32);
-        assert_eq!(bswap64(0x0122334455667708i64), 0x0877665544332201i64);
+        assert_eq!(bswap16(0x0A0Bu16), 0x0B0Au16);
+        assert_eq!(bswap32(0x0ABBCC0Du32), 0x0DCCBB0Au32);
+        assert_eq!(bswap64(0x0122334455667708u64), 0x0877665544332201u64);
     }
 }