Undo the changes to bitmask validation messages

Author: farnoy

compiler/rustc_codegen_llvm/src/intrinsic.rs

@@ -1549,17 +1549,13 @@ fn generic_simd_intrinsic<'ll, 'tcx>(
             }
         );
 
-        let expected_int_bits = (mask_len.max(8) - 1).next_power_of_two();
-        let expected_bytes = mask_len / 8 + ((mask_len % 8 > 0) as u64);
-
         require!(
             matches!(mask_elem.kind(), ty::Int(_)),
-            InvalidMonomorphization::InvalidBitmask {
+            InvalidMonomorphization::ThirdArgElementType {
                 span,
                 name,
-                mask_ty,
-                expected_int_bits,
-                expected_bytes
+                expected_element: values_elem,
+                third_arg: mask_ty,
             }
         );
 
@@ -1645,17 +1641,13 @@ fn generic_simd_intrinsic<'ll, 'tcx>(
             }
         );
 
-        let expected_int_bits = (mask_len.max(8) - 1).next_power_of_two();
-        let expected_bytes = mask_len / 8 + ((mask_len % 8 > 0) as u64);
-
         require!(
             matches!(mask_elem.kind(), ty::Int(_)),
-            InvalidMonomorphization::InvalidBitmask {
+            InvalidMonomorphization::ThirdArgElementType {
                 span,
                 name,
-                mask_ty,
-                expected_int_bits,
-                expected_bytes
+                expected_element: values_elem,
+                third_arg: mask_ty,
             }
         );
 

tests/ui/simd/masked-load-store-build-fail.rs

@@ -41,7 +41,7 @@ fn main() {
             arr.as_ptr(),
             default
         );
-        //~^^^^^ ERROR invalid bitmask `Simd<u8, 4>`, expected `u8` or `[u8; 1]`
+        //~^^^^^ ERROR expected element type `u8` of third argument `Simd<u8, 4>` to be a signed integer type
 
         simd_masked_store(
             Simd([-1i8; 4]),
@@ -69,6 +69,6 @@ fn main() {
             arr.as_mut_ptr(),
             Simd([5u8; 4])
         );
-        //~^^^^^ ERROR invalid bitmask `Simd<u32, 4>`, expected `u8` or `[u8; 1]
+        //~^^^^^ ERROR expected element type `u8` of third argument `Simd<u32, 4>` to be a signed integer type
     }
 }

tests/ui/simd/masked-load-store-build-fail.stderr

@@ -28,7 +28,7 @@ LL | |             Simd::<u32, 4>([9; 4])
 LL | |         );
    | |_________^
 
-error[E0511]: invalid monomorphization of `simd_masked_load` intrinsic: invalid bitmask `Simd<u8, 4>`, expected `u8` or `[u8; 1]`
+error[E0511]: invalid monomorphization of `simd_masked_load` intrinsic: expected element type `u8` of third argument `Simd<u8, 4>` to be a signed integer type
   --> $DIR/masked-load-store-build-fail.rs:39:9
    |
 LL | /         simd_masked_load(
@@ -68,7 +68,7 @@ LL | |             Simd([5u8; 2])
 LL | |         );
    | |_________^
 
-error[E0511]: invalid monomorphization of `simd_masked_store` intrinsic: invalid bitmask `Simd<u32, 4>`, expected `u8` or `[u8; 1]`
+error[E0511]: invalid monomorphization of `simd_masked_store` intrinsic: expected element type `u8` of third argument `Simd<u32, 4>` to be a signed integer type
   --> $DIR/masked-load-store-build-fail.rs:67:9
    |
 LL | /         simd_masked_store(