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Simplify transmutes

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This commit is contained in:
Caleb Zulawski
2020-09-23 10:42:12 -04:00
parent 543bcd37e9
commit 872e8f62d6
15 changed files with 69 additions and 298 deletions
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37
crates/core_simd/src/macros.rs
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@@ -1,29 +1,25 @@
macro_rules! from_aligned {
{ unsafe $from:ty => $to:ty } => {
macro_rules! from_transmute {
{ unsafe $a:ty => $b:ty } => {
from_transmute!{ @impl $a => $b }
from_transmute!{ @impl $b => $a }
};
{ @impl $from:ty => $to:ty } => {
impl core::convert::From<$from> for $to {
#[inline]
fn from(value: $from) -> $to {
assert_eq!(core::mem::size_of::<$from>(), core::mem::size_of::<$to>());
assert!(core::mem::align_of::<$from>() >= core::mem::align_of::<$to>());
unsafe { core::mem::transmute(value) }
}
}
};
{ unsafe $a:ty |bidirectional| $b:ty } => {
from_aligned!{ unsafe $a => $b }
from_aligned!{ unsafe $b => $a }
}
}
macro_rules! from_unaligned {
{ unsafe $from:ty => $to:ty } => {
impl core::convert::From<$from> for $to {
#[inline]
fn from(value: $from) -> $to {
assert_eq!(core::mem::size_of::<$from>(), core::mem::size_of::<$to>());
unsafe { (&value as *const $from as *const $to).read_unaligned() }
}
}
macro_rules! from_transmute_x86 {
{ unsafe $generic:ty => $intel:ident } => {
#[cfg(target_arch = "x86")]
from_transmute! { unsafe $generic => core::arch::x86::$intel }
#[cfg(target_arch = "x86_64")]
from_transmute! { unsafe $generic => core::arch::x86_64::$intel }
}
}
@@ -61,11 +57,8 @@ macro_rules! define_type {
}
}
// vector to array
from_aligned! { unsafe $name => [$type; $lanes] }
// array to vector
from_unaligned! { unsafe [$type; $lanes] => $name }
// vector/array conversion
from_transmute! { unsafe $name => [$type; $lanes] }
// splat
impl From<$type> for $name {