Changed implementation of _mm{256,512}_alignr_epi8 to match that of _mm_alignr_epi8 in ssse3.rs, also removed the import of the unreachable unchecked hint as it was no longer necessary

2 files changed, 149 insertions, 350 deletions

diff --git a/library/stdarch/crates/core_arch/src/x86/avx2.rs b/library/stdarch/crates/core_arch/src/x86/avx2.rs
index 2e834006333..8acf10e9f91 100644
--- a/library/stdarch/crates/core_arch/src/x86/avx2.rs
+++ b/library/stdarch/crates/core_arch/src/x86/avx2.rs
@@ -18,7 +18,7 @@
 //! [wiki_avx]: https://en.wikipedia.org/wiki/Advanced_Vector_Extensions
 //! [wiki_fma]: https://en.wikipedia.org/wiki/Fused_multiply-accumulate
 
-use core::hint::unreachable_unchecked;
+
 
 use crate::core_arch::{simd::*, x86::*};
 use crate::intrinsics::simd::*;
@@ -170,158 +170,74 @@ pub fn _mm256_adds_epu16(a: __m256i, b: __m256i) -> __m256i {
 #[stable(feature = "simd_x86", since = "1.27.0")]
 pub fn _mm256_alignr_epi8<const IMM8: i32>(a: __m256i, b: __m256i) -> __m256i {
     static_assert_uimm_bits!(IMM8, 8);
+    
+    
+    // If palignr is shifting the pair of vectors more than the size of two
+    // lanes, emit zero.
+    if IMM8 >= 32 {
+        return _mm256_setzero_si256();
+    }
+    // If palignr is shifting the pair of input vectors more than one lane,
+    // but less than two lanes, convert to shifting in zeroes.
+    let (a, b) = if IMM8 > 16 {
+        (_mm256_setzero_si256(), a)
+    } else {
+        (a, b)
+    };
     unsafe {
-        // If palignr is shifting the pair of vectors more than the size of two
-        // lanes, emit zero.
-        if IMM8 >= 32 {
-            return _mm256_setzero_si256();
-        }
-        // If palignr is shifting the pair of input vectors more than one lane,
-        // but less than two lanes, convert to shifting in zeroes.
-        let (a, b) = if IMM8 > 16 {
-            (_mm256_setzero_si256(), a)
-        } else {
-            (a, b)
-        };
-
-        let a = a.as_i8x32();
-        let b = b.as_i8x32();
-
-        if IMM8 == 16 {
-            return transmute(a);
-        }
-
-        let r: i8x32 = match IMM8 % 16 {
-            0 => simd_shuffle!(
-                b,
-                a,
-                [
-                    0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21,
-                    22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
-                ],
-            ),
-            1 => simd_shuffle!(
-                b,
-                a,
-                [
-                    1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 32, 17, 18, 19, 20, 21, 22,
-                    23, 24, 25, 26, 27, 28, 29, 30, 31, 48,
-                ],
-            ),
-            2 => simd_shuffle!(
-                b,
-                a,
-                [
-                    2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 32, 33, 18, 19, 20, 21, 22, 23,
-                    24, 25, 26, 27, 28, 29, 30, 31, 48, 49,
-                ],
-            ),
-            3 => simd_shuffle!(
-                b,
-                a,
-                [
-                    3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 32, 33, 34, 19, 20, 21, 22, 23,
-                    24, 25, 26, 27, 28, 29, 30, 31, 48, 49, 50,
-                ],
-            ),
-            4 => simd_shuffle!(
-                b,
-                a,
-                [
-                    4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 32, 33, 34, 35, 20, 21, 22, 23, 24,
-                    25, 26, 27, 28, 29, 30, 31, 48, 49, 50, 51,
-                ],
-            ),
-            5 => simd_shuffle!(
-                b,
-                a,
-                [
-                    5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 32, 33, 34, 35, 36, 21, 22, 23, 24, 25,
-                    26, 27, 28, 29, 30, 31, 48, 49, 50, 51, 52,
-                ],
-            ),
-            6 => simd_shuffle!(
-                b,
-                a,
-                [
-                    6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 32, 33, 34, 35, 36, 37, 22, 23, 24, 25, 26,
-                    27, 28, 29, 30, 31, 48, 49, 50, 51, 52, 53,
-                ],
-            ),
-            7 => simd_shuffle!(
-                b,
-                a,
-                [
-                    7, 8, 9, 10, 11, 12, 13, 14, 15, 32, 33, 34, 35, 36, 37, 38, 23, 24, 25, 26,
-                    27, 28, 29, 30, 31, 48, 49, 50, 51, 52, 53, 54,
-                ],
-            ),
-            8 => simd_shuffle!(
-                b,
-                a,
-                [
-                    8, 9, 10, 11, 12, 13, 14, 15, 32, 33, 34, 35, 36, 37, 38, 39, 24, 25, 26, 27,
-                    28, 29, 30, 31, 48, 49, 50, 51, 52, 53, 54, 55,
-                ],
-            ),
-            9 => simd_shuffle!(
-                b,
-                a,
-                [
-                    9, 10, 11, 12, 13, 14, 15, 32, 33, 34, 35, 36, 37, 38, 39, 40, 25, 26, 27, 28,
-                    29, 30, 31, 48, 49, 50, 51, 52, 53, 54, 55, 56,
-                ],
-            ),
-            10 => simd_shuffle!(
-                b,
-                a,
-                [
-                    10, 11, 12, 13, 14, 15, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 26, 27, 28, 29,
-                    30, 31, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57,
-                ],
-            ),
-            11 => simd_shuffle!(
-                b,
-                a,
-                [
-                    11, 12, 13, 14, 15, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 27, 28, 29, 30,
-                    31, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58,
-                ],
-            ),
-            12 => simd_shuffle!(
-                b,
-                a,
-                [
-                    12, 13, 14, 15, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 28, 29, 30, 31,
-                    48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,
-                ],
-            ),
-            13 => simd_shuffle!(
-                b,
-                a,
-                [
-                    13, 14, 15, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 29, 30, 31, 48,
-                    49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60,
-                ],
-            ),
-            14 => simd_shuffle!(
-                b,
-                a,
-                [
-                    14, 15, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 30, 31, 48, 49,
-                    50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,
-                ],
-            ),
-            15 => simd_shuffle!(
-                b,
-                a,
-                [
-                    15, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 31, 48, 49, 50,
-                    51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62,
-                ],
-            ),
-            _ => unreachable_unchecked(),
-        };
+	if IMM8 == 16 {
+	    return transmute(a)
+	}
+    }
+    const fn mask(shift: u32, i: u32) -> u32 {
+	let shift = shift % 16;
+	let mod_i = i%16;
+	if mod_i < (16 - shift) {
+	    i + shift
+	} else {
+	    i + 16 + shift
+	} 
+    }
+    
+    unsafe {
+        let r: i8x32 = simd_shuffle!(
+            b.as_i8x32(),
+            a.as_i8x32(),
+            [
+                mask(IMM8 as u32, 0),
+                mask(IMM8 as u32, 1),
+                mask(IMM8 as u32, 2),
+                mask(IMM8 as u32, 3),
+                mask(IMM8 as u32, 4),
+                mask(IMM8 as u32, 5),
+                mask(IMM8 as u32, 6),
+                mask(IMM8 as u32, 7),
+                mask(IMM8 as u32, 8),
+                mask(IMM8 as u32, 9),
+                mask(IMM8 as u32, 10),
+                mask(IMM8 as u32, 11),
+                mask(IMM8 as u32, 12),
+                mask(IMM8 as u32, 13),
+                mask(IMM8 as u32, 14),
+                mask(IMM8 as u32, 15),
+		mask(IMM8 as u32, 16),
+                mask(IMM8 as u32, 17),
+                mask(IMM8 as u32, 18),
+                mask(IMM8 as u32, 19),
+                mask(IMM8 as u32, 20),
+                mask(IMM8 as u32, 21),
+                mask(IMM8 as u32, 22),
+                mask(IMM8 as u32, 23),
+                mask(IMM8 as u32, 24),
+                mask(IMM8 as u32, 25),
+                mask(IMM8 as u32, 26),
+                mask(IMM8 as u32, 27),
+                mask(IMM8 as u32, 28),
+                mask(IMM8 as u32, 29),
+                mask(IMM8 as u32, 30),
+                mask(IMM8 as u32, 31),
+            ],
+        );
         transmute(r)
     }
 }
diff --git a/library/stdarch/crates/core_arch/src/x86/avx512bw.rs b/library/stdarch/crates/core_arch/src/x86/avx512bw.rs
index ba3c28cd5fe..e8807c4c956 100644
--- a/library/stdarch/crates/core_arch/src/x86/avx512bw.rs
+++ b/library/stdarch/crates/core_arch/src/x86/avx512bw.rs
@@ -4,7 +4,7 @@ use crate::{
     ptr,
 };
 
-use core::hint::unreachable_unchecked;
+
 
 #[cfg(test)]
 use stdarch_test::assert_instr;
@@ -11316,206 +11316,89 @@ pub fn _mm512_alignr_epi8<const IMM8: i32>(a: __m512i, b: __m512i) -> __m512i {
         } else {
             (a, b)
         };
-        let a = a.as_i8x64();
-        let b = b.as_i8x64();
         if IMM8 == 16 {
             return transmute(a);
         }
-        let r: i8x64 = match IMM8 % 16 {
-            0 => {
-                simd_shuffle!(
-                    b,
-                    a,
-                    [
-                        0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,
-                        21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39,
-                        40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58,
-                        59, 60, 61, 62, 63,
-                    ],
-                )
-            }
-            1 => {
-                simd_shuffle!(
-                    b,
-                    a,
-                    [
-                        1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 64, 17, 18, 19, 20, 21,
-                        22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 80, 33, 34, 35, 36, 37, 38, 39, 40,
-                        41, 42, 43, 44, 45, 46, 47, 96, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,
-                        60, 61, 62, 63, 112,
-                    ],
-                )
-            }
-            2 => {
-                simd_shuffle!(
-                    b,
-                    a,
-                    [
-                        2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 64, 65, 18, 19, 20, 21, 22,
-                        23, 24, 25, 26, 27, 28, 29, 30, 31, 80, 81, 34, 35, 36, 37, 38, 39, 40, 41,
-                        42, 43, 44, 45, 46, 47, 96, 97, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60,
-                        61, 62, 63, 112, 113,
-                    ],
-                )
-            }
-            3 => {
-                simd_shuffle!(
-                    b,
-                    a,
-                    [
-                        3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 64, 65, 66, 19, 20, 21, 22,
-                        23, 24, 25, 26, 27, 28, 29, 30, 31, 80, 81, 82, 35, 36, 37, 38, 39, 40, 41,
-                        42, 43, 44, 45, 46, 47, 96, 97, 98, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60,
-                        61, 62, 63, 112, 113, 114,
-                    ],
-                )
-            }
-            4 => {
-                simd_shuffle!(
-                    b,
-                    a,
-                    [
-                        4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 64, 65, 66, 67, 20, 21, 22, 23,
-                        24, 25, 26, 27, 28, 29, 30, 31, 80, 81, 82, 83, 36, 37, 38, 39, 40, 41, 42,
-                        43, 44, 45, 46, 47, 96, 97, 98, 99, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,
-                        62, 63, 112, 113, 114, 115,
-                    ],
-                )
-            }
-            5 => {
-                simd_shuffle!(
-                    b,
-                    a,
-                    [
-                        5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 64, 65, 66, 67, 68, 21, 22, 23, 24,
-                        25, 26, 27, 28, 29, 30, 31, 80, 81, 82, 83, 84, 37, 38, 39, 40, 41, 42, 43,
-                        44, 45, 46, 47, 96, 97, 98, 99, 100, 53, 54, 55, 56, 57, 58, 59, 60, 61,
-                        62, 63, 112, 113, 114, 115, 116,
-                    ],
-                )
-            }
-            6 => {
-                simd_shuffle!(
-                    b,
-                    a,
-                    [
-                        6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 64, 65, 66, 67, 68, 69, 22, 23, 24, 25,
-                        26, 27, 28, 29, 30, 31, 80, 81, 82, 83, 84, 85, 38, 39, 40, 41, 42, 43, 44,
-                        45, 46, 47, 96, 97, 98, 99, 100, 101, 54, 55, 56, 57, 58, 59, 60, 61, 62,
-                        63, 112, 113, 114, 115, 116, 117,
-                    ],
-                )
-            }
-            7 => {
-                simd_shuffle!(
-                    b,
-                    a,
-                    [
-                        7, 8, 9, 10, 11, 12, 13, 14, 15, 64, 65, 66, 67, 68, 69, 70, 23, 24, 25,
-                        26, 27, 28, 29, 30, 31, 80, 81, 82, 83, 84, 85, 86, 39, 40, 41, 42, 43, 44,
-                        45, 46, 47, 96, 97, 98, 99, 100, 101, 102, 55, 56, 57, 58, 59, 60, 61, 62,
-                        63, 112, 113, 114, 115, 116, 117, 118,
-                    ],
-                )
-            }
-            8 => {
-                simd_shuffle!(
-                    b,
-                    a,
-                    [
-                        8, 9, 10, 11, 12, 13, 14, 15, 64, 65, 66, 67, 68, 69, 70, 71, 24, 25, 26,
-                        27, 28, 29, 30, 31, 80, 81, 82, 83, 84, 85, 86, 87, 40, 41, 42, 43, 44, 45,
-                        46, 47, 96, 97, 98, 99, 100, 101, 102, 103, 56, 57, 58, 59, 60, 61, 62, 63,
-                        112, 113, 114, 115, 116, 117, 118, 119,
-                    ],
-                )
-            }
-            9 => {
-                simd_shuffle!(
-                    b,
-                    a,
-                    [
-                        9, 10, 11, 12, 13, 14, 15, 64, 65, 66, 67, 68, 69, 70, 71, 72, 25, 26, 27,
-                        28, 29, 30, 31, 80, 81, 82, 83, 84, 85, 86, 87, 88, 41, 42, 43, 44, 45, 46,
-                        47, 96, 97, 98, 99, 100, 101, 102, 103, 104, 57, 58, 59, 60, 61, 62, 63,
-                        112, 113, 114, 115, 116, 117, 118, 119, 120,
-                    ],
-                )
-            }
-            10 => {
-                simd_shuffle!(
-                    b,
-                    a,
-                    [
-                        10, 11, 12, 13, 14, 15, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 26, 27, 28,
-                        29, 30, 31, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 42, 43, 44, 45, 46, 47,
-                        96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 58, 59, 60, 61, 62, 63, 112,
-                        113, 114, 115, 116, 117, 118, 119, 120, 121,
-                    ],
-                )
-            }
-            11 => {
-                simd_shuffle!(
-                    b,
-                    a,
-                    [
-                        11, 12, 13, 14, 15, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 27, 28, 29,
-                        30, 31, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 43, 44, 45, 46, 47, 96,
-                        97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 59, 60, 61, 62, 63, 112,
-                        113, 114, 115, 116, 117, 118, 119, 120, 121, 122,
-                    ],
-                )
-            }
-            12 => {
-                simd_shuffle!(
-                    b,
-                    a,
-                    [
-                        12, 13, 14, 15, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 28, 29, 30,
-                        31, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 44, 45, 46, 47, 96, 97,
-                        98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 60, 61, 62, 63, 112, 113,
-                        114, 115, 116, 117, 118, 119, 120, 121, 122, 123,
-                    ],
-                )
-            }
-            13 => {
-                simd_shuffle!(
-                    b,
-                    a,
-                    [
-                        13, 14, 15, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 29, 30, 31,
-                        80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 45, 46, 47, 96, 97, 98,
-                        99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 61, 62, 63, 112, 113, 114,
-                        115, 116, 117, 118, 119, 120, 121, 122, 123, 124,
-                    ],
-                )
-            }
-            14 => {
-                simd_shuffle!(
-                    b,
-                    a,
-                    [
-                        14, 15, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 30, 31, 80,
-                        81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 46, 47, 96, 97, 98, 99,
-                        100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 62, 63, 112, 113, 114,
-                        115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125,
-                    ],
-                )
-            }
-            15 => {
-                simd_shuffle!(
-                    b,
-                    a,
-                    [
-                        15, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 31, 80, 81,
-                        82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 47, 96, 97, 98, 99,
-                        100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 63, 112, 113, 114,
-                        115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,
-                    ],
-                )
-            }
-            _ => unreachable_unchecked(),
-        };
+	const fn mask(shift: u32, i: u32) -> u32 {
+	    let shift = shift % 16;
+	    let mod_i = i%16;
+	    if mod_i < (16 - shift) {
+		i + shift
+	    } else {
+		i + 48 + shift
+	    } 
+	}
+	
+        let r: i8x64 = simd_shuffle!(
+            b.as_i8x64(),
+            a.as_i8x64(),
+            [
+                mask(IMM8 as u32, 0),
+                mask(IMM8 as u32, 1),
+                mask(IMM8 as u32, 2),
+                mask(IMM8 as u32, 3),
+                mask(IMM8 as u32, 4),
+                mask(IMM8 as u32, 5),
+                mask(IMM8 as u32, 6),
+                mask(IMM8 as u32, 7),
+                mask(IMM8 as u32, 8),
+                mask(IMM8 as u32, 9),
+                mask(IMM8 as u32, 10),
+                mask(IMM8 as u32, 11),
+                mask(IMM8 as u32, 12),
+                mask(IMM8 as u32, 13),
+                mask(IMM8 as u32, 14),
+                mask(IMM8 as u32, 15),
+		mask(IMM8 as u32, 16),
+                mask(IMM8 as u32, 17),
+                mask(IMM8 as u32, 18),
+                mask(IMM8 as u32, 19),
+                mask(IMM8 as u32, 20),
+                mask(IMM8 as u32, 21),
+                mask(IMM8 as u32, 22),
+                mask(IMM8 as u32, 23),
+                mask(IMM8 as u32, 24),
+                mask(IMM8 as u32, 25),
+                mask(IMM8 as u32, 26),
+                mask(IMM8 as u32, 27),
+                mask(IMM8 as u32, 28),
+                mask(IMM8 as u32, 29),
+                mask(IMM8 as u32, 30),
+                mask(IMM8 as u32, 31),
+		mask(IMM8 as u32, 32),
+                mask(IMM8 as u32, 33),
+                mask(IMM8 as u32, 34),
+                mask(IMM8 as u32, 35),
+                mask(IMM8 as u32, 36),
+                mask(IMM8 as u32, 37),
+                mask(IMM8 as u32, 38),
+                mask(IMM8 as u32, 39),
+                mask(IMM8 as u32, 40),
+                mask(IMM8 as u32, 41),
+                mask(IMM8 as u32, 42),
+                mask(IMM8 as u32, 43),
+                mask(IMM8 as u32, 44),
+                mask(IMM8 as u32, 45),
+                mask(IMM8 as u32, 46),
+                mask(IMM8 as u32, 47),
+		mask(IMM8 as u32, 48),
+                mask(IMM8 as u32, 49),
+                mask(IMM8 as u32, 50),
+                mask(IMM8 as u32, 51),
+                mask(IMM8 as u32, 52),
+                mask(IMM8 as u32, 53),
+                mask(IMM8 as u32, 54),
+                mask(IMM8 as u32, 55),
+                mask(IMM8 as u32, 56),
+                mask(IMM8 as u32, 57),
+                mask(IMM8 as u32, 58),
+                mask(IMM8 as u32, 59),
+                mask(IMM8 as u32, 60),
+                mask(IMM8 as u32, 61),
+                mask(IMM8 as u32, 62),
+                mask(IMM8 as u32, 63),
+            ],
+        );
         transmute(r)
     }
 }