Auto merge of #97414 - LYF1999:yf/cachealign, r=Mark-Simulacrum

use 128 cache align for aarch64

the cache line size of m1 mac is 128.
so use `align(128)` for m1 mac

here is `sysctl -a hw machdep.cpu` output on m1 mac
```
hw.ncpu: 10
hw.byteorder: 1234
hw.memsize: 68719476736
hw.activecpu: 10
hw.perflevel0.physicalcpu: 8
hw.perflevel0.physicalcpu_max: 8
hw.perflevel0.logicalcpu: 8
hw.perflevel0.logicalcpu_max: 8
hw.perflevel0.l1icachesize: 196608
hw.perflevel0.l1dcachesize: 131072
hw.perflevel0.l2cachesize: 12582912
hw.perflevel0.cpusperl2: 4
hw.perflevel1.physicalcpu: 2
hw.perflevel1.physicalcpu_max: 2
hw.perflevel1.logicalcpu: 2
hw.perflevel1.logicalcpu_max: 2
hw.perflevel1.l1icachesize: 131072
hw.perflevel1.l1dcachesize: 65536
hw.perflevel1.l2cachesize: 4194304
hw.perflevel1.cpusperl2: 2
hw.optional.arm.FEAT_FlagM: 1
hw.optional.arm.FEAT_FlagM2: 1
hw.optional.arm.FEAT_FHM: 1
hw.optional.arm.FEAT_DotProd: 1
hw.optional.arm.FEAT_SHA3: 1
hw.optional.arm.FEAT_RDM: 1
hw.optional.arm.FEAT_LSE: 1
hw.optional.arm.FEAT_SHA256: 1
hw.optional.arm.FEAT_SHA512: 1
hw.optional.arm.FEAT_SHA1: 1
hw.optional.arm.FEAT_AES: 1
hw.optional.arm.FEAT_PMULL: 1
hw.optional.arm.FEAT_SPECRES: 0
hw.optional.arm.FEAT_SB: 1
hw.optional.arm.FEAT_FRINTTS: 1
hw.optional.arm.FEAT_LRCPC: 1
hw.optional.arm.FEAT_LRCPC2: 1
hw.optional.arm.FEAT_FCMA: 1
hw.optional.arm.FEAT_JSCVT: 1
hw.optional.arm.FEAT_PAuth: 1
hw.optional.arm.FEAT_PAuth2: 0
hw.optional.arm.FEAT_FPAC: 0
hw.optional.arm.FEAT_DPB: 1
hw.optional.arm.FEAT_DPB2: 1
hw.optional.arm.FEAT_BF16: 0
hw.optional.arm.FEAT_I8MM: 0
hw.optional.arm.FEAT_ECV: 1
hw.optional.arm.FEAT_LSE2: 1
hw.optional.arm.FEAT_CSV2: 1
hw.optional.arm.FEAT_CSV3: 1
hw.optional.arm.FEAT_FP16: 1
hw.optional.arm.FEAT_SSBS: 1
hw.optional.arm.FEAT_BTI: 0
hw.optional.floatingpoint: 1
hw.optional.neon: 1
hw.optional.neon_hpfp: 1
hw.optional.neon_fp16: 1
hw.optional.armv8_1_atomics: 1
hw.optional.armv8_2_fhm: 1
hw.optional.armv8_2_sha512: 1
hw.optional.armv8_2_sha3: 1
hw.optional.armv8_3_compnum: 1
hw.optional.watchpoint: 4
hw.optional.breakpoint: 6
hw.optional.armv8_crc32: 1
hw.optional.armv8_gpi: 1
hw.optional.AdvSIMD: 1
hw.optional.AdvSIMD_HPFPCvt: 1
hw.optional.ucnormal_mem: 1
hw.optional.arm64: 1
hw.features.allows_security_research: 0
hw.physicalcpu: 10
hw.physicalcpu_max: 10
hw.logicalcpu: 10
hw.logicalcpu_max: 10
hw.cputype: 16777228
hw.cpusubtype: 2
hw.cpu64bit_capable: 1
hw.cpufamily: 458787763
hw.cpusubfamily: 5
hw.cacheconfig: 10 1 2 0 0 0 0 0 0 0
hw.cachesize: 3373957120 65536 4194304 0 0 0 0 0 0 0
hw.pagesize: 16384
hw.pagesize32: 16384
hw.cachelinesize: 128
hw.l1icachesize: 131072
hw.l1dcachesize: 65536
hw.l2cachesize: 4194304
hw.tbfrequency: 24000000
hw.packages: 1
hw.osenvironment:
hw.ephemeral_storage: 0
hw.use_recovery_securityd: 0
hw.use_kernelmanagerd: 1
hw.serialdebugmode: 0
hw.nperflevels: 2
hw.targettype: J316c
machdep.cpu.cores_per_package: 10
machdep.cpu.core_count: 10
machdep.cpu.logical_per_package: 10
machdep.cpu.thread_count: 10
machdep.cpu.brand_string: Apple M1 Max
```

1 files changed, 2 insertions, 1 deletions

diff --git a/library/std/src/sync/mpsc/cache_aligned.rs b/library/std/src/sync/mpsc/cache_aligned.rs
index f95b0ddd589..9197f0d6e6c 100644
--- a/library/std/src/sync/mpsc/cache_aligned.rs
+++ b/library/std/src/sync/mpsc/cache_aligned.rs
@@ -1,7 +1,8 @@
 use crate::ops::{Deref, DerefMut};
 
 #[derive(Copy, Clone, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]
-#[repr(align(64))]
+#[cfg_attr(target_arch = "aarch64", repr(align(128)))]
+#[cfg_attr(not(target_arch = "aarch64"), repr(align(64)))]
 pub(super) struct CacheAligned<T>(pub T);
 
 impl<T> Deref for CacheAligned<T> {