[libc] Fix memmove macros for unreocognized targets

2025-03-14T15:25:42+00:00

[libc] Default to `byte_per_byte` instead of erroring (#131340)

2025-03-14T15:10:53+00:00

Summary:
Right now a lot of the memory functions error if we don't have specific
handling for them. This is weird because we have a generic
implementation that should just be used whenever someone hasn't written
a more optimized version. This allows us to use the `libc` headers with
more architectures from the `shared/` directory without worrying about
it breaking.

[libc] Fix all imports of src/string/memory_utils (#114939)

2025-02-05T17:24:44+00:00

Fixed imports for all files *within* `libc/src/string/memory_utils`.
Note: This doesn't include **all** files that need to be fixed.

Fixes #86579

[libc] Migrate to using LIBC_NAMESPACE_DECL for namespace declaration (#98597)

2024-07-12T16:28:41+00:00

This is a part of #97655.

Revert "[libc] Migrate to using LIBC_NAMESPACE_DECL for namespace declaration" (#98593)

2024-07-12T07:12:13+00:00

Reverts llvm/llvm-project#98075

bots are broken

[libc] Migrate to using LIBC_NAMESPACE_DECL for namespace declaration (#98075)

2024-07-11T19:35:22+00:00

This is a part of #97655.

[libc] Remove unnecessary call in memfunction dispatchers (#75800)

2023-12-19T12:57:44+00:00

Before this patch the compiler could generate unnecessary calls to the
selected implementation.
https://clang.llvm.org/docs/AttributeReference.html#flatten

[libc] memmove optimizations (#70043)

2023-10-26T11:40:25+00:00

1. Remove is_disjoint check for smaller sizes and reduce code bloat.

inline_memmove may handle some small sizes as efficiently
as inline_memcpy. For these sizes we may not do is_disjoint check.
This both avoids additional code for the most frequent smaller sizes
and removes code bloat (we don't need the memcpy logic for small sizes).
Here we heavily rely on inlining and dead code elimination: from the
first
inline_memmove we should get only handling of small sizes, and from
the second inline_memmove and inline_memcpy we should get only handling
of larger sizes.

2. Use the memcpy thresholds for memmove.
Memcpy thresholds were more carefully tuned.
This becomes more important since we use memmove
for all small sizes always now.

3. Fix boundary conditions for sizes = 16/32/64.
See the added comment for explanations.

Memmove function size drops from 885 to 715 bytes
due to removed duplication.

```
                 │  baseline   │             small-size              │
                 │   sec/op    │   sec/op     vs base                │
memmove/Google_A   3.208n ± 0%   2.911n ± 0%   -9.25% (n=100)
memmove/Google_B   4.113n ± 1%   3.428n ± 0%  -16.65% (n=100)
memmove/Google_D   5.838n ± 0%   4.158n ± 0%  -28.78% (n=100)
memmove/Google_S   4.712n ± 1%   3.899n ± 0%  -17.25% (n=100)
memmove/Google_U   3.609n ± 0%   3.247n ± 1%  -10.02% (n=100)
memmove/0          2.982n ± 0%   2.169n ± 0%  -27.26% (n=50)
memmove/1          3.253n ± 0%   2.168n ± 0%  -33.34% (n=50)
memmove/2          3.255n ± 0%   2.169n ± 0%  -33.38% (n=50)
memmove/3          3.259n ± 2%   2.175n ± 0%  -33.27% (p=0.000 n=50)
memmove/4          3.259n ± 0%   2.168n ± 5%  -33.46% (p=0.000 n=50)
memmove/5          2.488n ± 0%   1.926n ± 0%  -22.57% (p=0.000 n=50)
memmove/6          2.490n ± 0%   1.928n ± 0%  -22.59% (p=0.000 n=50)
memmove/7          2.492n ± 0%   1.927n ± 0%  -22.65% (p=0.000 n=50)
memmove/8          2.737n ± 0%   2.711n ± 0%   -0.97% (p=0.000 n=50)
memmove/9          2.736n ± 0%   2.711n ± 0%   -0.94% (p=0.000 n=50)
memmove/10         2.739n ± 0%   2.711n ± 0%   -1.04% (p=0.000 n=50)
memmove/11         2.740n ± 0%   2.711n ± 0%   -1.07% (p=0.000 n=50)
memmove/12         2.740n ± 0%   2.711n ± 0%   -1.09% (p=0.000 n=50)
memmove/13         2.744n ± 0%   2.711n ± 0%   -1.22% (p=0.000 n=50)
memmove/14         2.742n ± 0%   2.711n ± 0%   -1.14% (p=0.000 n=50)
memmove/15         2.742n ± 0%   2.711n ± 0%   -1.15% (p=0.000 n=50)
memmove/16         2.997n ± 0%   2.981n ± 0%   -0.52% (p=0.000 n=50)
memmove/17         2.998n ± 0%   2.981n ± 0%   -0.55% (p=0.000 n=50)
memmove/18         2.998n ± 0%   2.981n ± 0%   -0.55% (p=0.000 n=50)
memmove/19         2.999n ± 0%   2.982n ± 0%   -0.59% (p=0.000 n=50)
memmove/20         2.998n ± 0%   2.981n ± 0%   -0.55% (p=0.000 n=50)
memmove/21         3.000n ± 0%   2.981n ± 0%   -0.61% (p=0.000 n=50)
memmove/22         3.002n ± 0%   2.981n ± 0%   -0.68% (p=0.000 n=50)
memmove/23         3.002n ± 0%   2.981n ± 0%   -0.67% (p=0.000 n=50)
memmove/24         3.002n ± 0%   2.981n ± 0%   -0.70% (n=50)
memmove/25         3.002n ± 0%   2.981n ± 0%   -0.68% (p=0.000 n=50)
memmove/26         3.004n ± 0%   2.982n ± 0%   -0.74% (p=0.000 n=50)
memmove/27         3.005n ± 0%   2.981n ± 0%   -0.79% (n=50)
memmove/28         3.005n ± 0%   2.982n ± 0%   -0.77% (n=50)
memmove/29         3.009n ± 0%   2.981n ± 0%   -0.92% (n=50)
memmove/30         3.008n ± 0%   2.981n ± 0%   -0.89% (n=50)
memmove/31         3.007n ± 0%   2.982n ± 0%   -0.86% (n=50)
memmove/32         3.540n ± 0%   2.998n ± 0%  -15.31% (p=0.000 n=50)
memmove/33         3.544n ± 0%   2.997n ± 0%  -15.44% (p=0.000 n=50)
memmove/34         3.546n ± 0%   2.999n ± 0%  -15.42% (n=50)
memmove/35         3.545n ± 0%   2.999n ± 0%  -15.40% (n=50)
memmove/36         3.548n ± 0%   2.998n ± 0%  -15.52% (p=0.000 n=50)
memmove/37         3.546n ± 0%   3.000n ± 0%  -15.41% (n=50)
memmove/38         3.549n ± 0%   2.999n ± 0%  -15.49% (p=0.000 n=50)
memmove/39         3.549n ± 0%   2.999n ± 0%  -15.48% (p=0.000 n=50)
memmove/40         3.549n ± 0%   3.000n ± 0%  -15.46% (p=0.000 n=50)
memmove/41         3.550n ± 0%   3.001n ± 0%  -15.47% (n=50)
memmove/42         3.549n ± 0%   3.001n ± 0%  -15.43% (n=50)
memmove/43         3.552n ± 0%   3.001n ± 0%  -15.52% (p=0.000 n=50)
memmove/44         3.552n ± 0%   3.001n ± 0%  -15.51% (n=50)
memmove/45         3.552n ± 0%   3.002n ± 0%  -15.48% (n=50)
memmove/46         3.554n ± 0%   3.001n ± 0%  -15.55% (p=0.000 n=50)
memmove/47         3.556n ± 0%   3.002n ± 0%  -15.58% (p=0.000 n=50)
memmove/48         3.555n ± 0%   3.003n ± 0%  -15.54% (n=50)
memmove/49         3.557n ± 0%   3.002n ± 0%  -15.59% (p=0.000 n=50)
memmove/50         3.557n ± 0%   3.004n ± 0%  -15.55% (p=0.000 n=50)
memmove/51         3.556n ± 0%   3.004n ± 0%  -15.53% (p=0.000 n=50)
memmove/52         3.561n ± 0%   3.004n ± 0%  -15.65% (p=0.000 n=50)
memmove/53         3.558n ± 0%   3.004n ± 0%  -15.57% (p=0.000 n=50)
memmove/54         3.561n ± 0%   3.005n ± 0%  -15.62% (n=50)
memmove/55         3.560n ± 0%   3.006n ± 0%  -15.57% (n=50)
memmove/56         3.562n ± 0%   3.006n ± 0%  -15.60% (p=0.000 n=50)
memmove/57         3.563n ± 0%   3.006n ± 0%  -15.64% (n=50)
memmove/58         3.565n ± 0%   3.007n ± 0%  -15.64% (p=0.000 n=50)
memmove/59         3.564n ± 0%   3.006n ± 0%  -15.66% (p=0.000 n=50)
memmove/60         3.570n ± 0%   3.008n ± 0%  -15.74% (p=0.000 n=50)
memmove/61         3.566n ± 0%   3.009n ± 0%  -15.63% (p=0.000 n=50)
memmove/62         3.567n ± 0%   3.007n ± 0%  -15.70% (p=0.000 n=50)
memmove/63         3.568n ± 0%   3.008n ± 0%  -15.71% (p=0.000 n=50)
memmove/64         4.104n ± 0%   3.008n ± 0%  -26.70% (p=0.000 n=50)
memmove/65         4.126n ± 0%   3.662n ± 0%  -11.26% (p=0.000 n=50)
memmove/66         4.128n ± 0%   3.662n ± 0%  -11.29% (n=50)
memmove/67         4.129n ± 0%   3.662n ± 0%  -11.31% (n=50)
memmove/68         4.129n ± 0%   3.661n ± 0%  -11.33% (p=0.000 n=50)
memmove/69         4.130n ± 0%   3.662n ± 0%  -11.34% (p=0.000 n=50)
memmove/70         4.130n ± 0%   3.662n ± 0%  -11.33% (n=50)
memmove/71         4.132n ± 0%   3.662n ± 0%  -11.38% (p=0.000 n=50)
memmove/72         4.131n ± 0%   3.661n ± 0%  -11.39% (n=50)
memmove/73         4.135n ± 0%   3.661n ± 0%  -11.45% (p=0.000 n=50)
memmove/74         4.137n ± 0%   3.662n ± 0%  -11.49% (n=50)
memmove/75         4.138n ± 0%   3.662n ± 0%  -11.51% (p=0.000 n=50)
memmove/76         4.139n ± 0%   3.661n ± 0%  -11.56% (p=0.000 n=50)
memmove/77         4.136n ± 0%   3.662n ± 0%  -11.47% (p=0.000 n=50)
memmove/78         4.143n ± 0%   3.661n ± 0%  -11.62% (p=0.000 n=50)
memmove/79         4.142n ± 0%   3.661n ± 0%  -11.60% (n=50)
memmove/80         4.142n ± 0%   3.661n ± 0%  -11.62% (p=0.000 n=50)
memmove/81         4.140n ± 0%   3.661n ± 0%  -11.57% (n=50)
memmove/82         4.146n ± 0%   3.661n ± 0%  -11.69% (n=50)
memmove/83         4.143n ± 0%   3.661n ± 0%  -11.63% (p=0.000 n=50)
memmove/84         4.143n ± 0%   3.661n ± 0%  -11.63% (n=50)
memmove/85         4.147n ± 0%   3.661n ± 0%  -11.73% (p=0.000 n=50)
memmove/86         4.142n ± 0%   3.661n ± 0%  -11.62% (p=0.000 n=50)
memmove/87         4.147n ± 0%   3.661n ± 0%  -11.72% (p=0.000 n=50)
memmove/88         4.148n ± 0%   3.661n ± 0%  -11.74% (n=50)
memmove/89         4.152n ± 0%   3.661n ± 0%  -11.84% (n=50)
memmove/90         4.151n ± 0%   3.661n ± 0%  -11.81% (n=50)
memmove/91         4.150n ± 0%   3.661n ± 0%  -11.78% (n=50)
memmove/92         4.153n ± 0%   3.661n ± 0%  -11.86% (n=50)
memmove/93         4.158n ± 0%   3.661n ± 0%  -11.95% (n=50)
memmove/94         4.157n ± 0%   3.661n ± 0%  -11.95% (p=0.000 n=50)
memmove/95         4.155n ± 0%   3.661n ± 0%  -11.90% (p=0.000 n=50)
memmove/96         4.149n ± 0%   3.660n ± 0%  -11.79% (n=50)
memmove/97         4.157n ± 0%   3.661n ± 0%  -11.94% (n=50)
memmove/98         4.157n ± 0%   3.661n ± 0%  -11.94% (n=50)
memmove/99         4.168n ± 0%   3.661n ± 0%  -12.17% (p=0.000 n=50)
memmove/100        4.159n ± 0%   3.660n ± 0%  -12.00% (p=0.000 n=50)
memmove/101        4.161n ± 0%   3.660n ± 0%  -12.03% (p=0.000 n=50)
memmove/102        4.165n ± 0%   3.660n ± 0%  -12.12% (p=0.000 n=50)
memmove/103        4.164n ± 0%   3.661n ± 0%  -12.08% (n=50)
memmove/104        4.164n ± 0%   3.660n ± 0%  -12.11% (n=50)
memmove/105        4.165n ± 0%   3.660n ± 0%  -12.12% (p=0.000 n=50)
memmove/106        4.166n ± 0%   3.660n ± 0%  -12.15% (n=50)
memmove/107        4.171n ± 0%   3.660n ± 1%  -12.26% (p=0.000 n=50)
memmove/108        4.173n ± 0%   3.660n ± 0%  -12.30% (p=0.000 n=50)
memmove/109        4.170n ± 0%   3.660n ± 0%  -12.24% (n=50)
memmove/110        4.174n ± 0%   3.660n ± 0%  -12.31% (n=50)
memmove/111        4.176n ± 0%   3.660n ± 0%  -12.35% (p=0.000 n=50)
memmove/112        4.174n ± 0%   3.659n ± 0%  -12.34% (p=0.000 n=50)
memmove/113        4.176n ± 0%   3.660n ± 0%  -12.35% (n=50)
memmove/114        4.182n ± 0%   3.660n ± 0%  -12.49% (n=50)
memmove/115        4.185n ± 0%   3.660n ± 0%  -12.55% (n=50)
memmove/116        4.184n ± 0%   3.659n ± 0%  -12.54% (n=50)
memmove/117        4.182n ± 0%   3.660n ± 0%  -12.50% (n=50)
memmove/118        4.188n ± 0%   3.660n ± 0%  -12.61% (n=50)
memmove/119        4.186n ± 0%   3.660n ± 0%  -12.57% (p=0.000 n=50)
memmove/120        4.189n ± 0%   3.659n ± 0%  -12.63% (n=50)
memmove/121        4.187n ± 0%   3.660n ± 0%  -12.60% (n=50)
memmove/122        4.186n ± 0%   3.660n ± 0%  -12.58% (n=50)
memmove/123        4.187n ± 0%   3.660n ± 0%  -12.60% (n=50)
memmove/124        4.189n ± 0%   3.659n ± 0%  -12.65% (n=50)
memmove/125        4.195n ± 0%   3.659n ± 0%  -12.78% (n=50)
memmove/126        4.197n ± 0%   3.659n ± 0%  -12.81% (n=50)
memmove/127        4.194n ± 0%   3.659n ± 0%  -12.75% (n=50)
memmove/128        5.035n ± 0%   3.659n ± 0%  -27.32% (n=50)
memmove/129        5.127n ± 0%   5.164n ± 0%   +0.73% (p=0.000 n=50)
memmove/130        5.130n ± 0%   5.176n ± 0%   +0.88% (p=0.000 n=50)
memmove/131        5.127n ± 0%   5.180n ± 0%   +1.05% (p=0.000 n=50)
memmove/132        5.131n ± 0%   5.169n ± 0%   +0.75% (p=0.000 n=50)
memmove/133        5.137n ± 0%   5.179n ± 0%   +0.81% (p=0.000 n=50)
memmove/134        5.140n ± 0%   5.178n ± 0%   +0.74% (p=0.000 n=50)
memmove/135        5.141n ± 0%   5.187n ± 0%   +0.88% (p=0.000 n=50)
memmove/136        5.133n ± 0%   5.184n ± 0%   +0.99% (p=0.000 n=50)
memmove/137        5.148n ± 0%   5.186n ± 0%   +0.73% (p=0.000 n=50)
memmove/138        5.143n ± 0%   5.189n ± 0%   +0.88% (p=0.000 n=50)
memmove/139        5.142n ± 0%   5.192n ± 0%   +0.97% (p=0.000 n=50)
memmove/140        5.141n ± 0%   5.192n ± 0%   +1.01% (p=0.000 n=50)
memmove/141        5.155n ± 0%   5.188n ± 0%   +0.64% (p=0.000 n=50)
memmove/142        5.146n ± 0%   5.192n ± 0%   +0.90% (p=0.000 n=50)
memmove/143        5.142n ± 0%   5.203n ± 0%   +1.19% (p=0.000 n=50)
memmove/144        5.146n ± 0%   5.197n ± 0%   +0.99% (p=0.000 n=50)
memmove/145        5.146n ± 0%   5.196n ± 0%   +0.97% (p=0.000 n=50)
memmove/146        5.151n ± 0%   5.207n ± 0%   +1.10% (p=0.000 n=50)
memmove/147        5.151n ± 0%   5.205n ± 0%   +1.06% (p=0.000 n=50)
memmove/148        5.156n ± 0%   5.190n ± 0%   +0.66% (p=0.000 n=50)
memmove/149        5.158n ± 0%   5.212n ± 0%   +1.04% (p=0.000 n=50)
memmove/150        5.160n ± 0%   5.203n ± 0%   +0.84% (p=0.000 n=50)
memmove/151        5.167n ± 0%   5.210n ± 0%   +0.83% (p=0.000 n=50)
memmove/152        5.157n ± 0%   5.206n ± 0%   +0.94% (p=0.000 n=50)
memmove/153        5.170n ± 0%   5.211n ± 0%   +0.80% (p=0.000 n=50)
memmove/154        5.169n ± 0%   5.222n ± 0%   +1.02% (p=0.000 n=50)
memmove/155        5.171n ± 0%   5.215n ± 0%   +0.87% (p=0.000 n=50)
memmove/156        5.174n ± 0%   5.214n ± 0%   +0.78% (p=0.000 n=50)
memmove/157        5.171n ± 0%   5.218n ± 0%   +0.92% (p=0.000 n=50)
memmove/158        5.168n ± 0%   5.224n ± 0%   +1.09% (p=0.000 n=50)
memmove/159        5.179n ± 0%   5.218n ± 0%   +0.76% (p=0.000 n=50)
memmove/160        5.170n ± 0%   5.219n ± 0%   +0.95% (p=0.000 n=50)
memmove/161        5.187n ± 0%   5.220n ± 0%   +0.64% (p=0.000 n=50)
memmove/162        5.189n ± 0%   5.234n ± 0%   +0.86% (p=0.000 n=50)
memmove/163        5.199n ± 0%   5.250n ± 0%   +0.99% (p=0.000 n=50)
memmove/164        5.205n ± 0%   5.260n ± 0%   +1.04% (p=0.000 n=50)
memmove/165        5.208n ± 0%   5.261n ± 0%   +1.01% (p=0.000 n=50)
memmove/166        5.227n ± 0%   5.275n ± 0%   +0.91% (p=0.000 n=50)
memmove/167        5.233n ± 0%   5.281n ± 0%   +0.92% (p=0.000 n=50)
memmove/168        5.236n ± 0%   5.295n ± 0%   +1.12% (p=0.000 n=50)
memmove/169        5.256n ± 0%   5.297n ± 0%   +0.79% (p=0.000 n=50)
memmove/170        5.259n ± 0%   5.302n ± 0%   +0.80% (p=0.000 n=50)
memmove/171        5.269n ± 0%   5.321n ± 0%   +0.97% (p=0.000 n=50)
memmove/172        5.266n ± 0%   5.318n ± 0%   +0.98% (p=0.000 n=50)
memmove/173        5.272n ± 0%   5.330n ± 0%   +1.09% (p=0.000 n=50)
memmove/174        5.284n ± 0%   5.331n ± 0%   +0.89% (p=0.000 n=50)
memmove/175        5.284n ± 0%   5.322n ± 0%   +0.72% (p=0.000 n=50)
memmove/176        5.298n ± 0%   5.337n ± 0%   +0.74% (p=0.000 n=50)
memmove/177        5.282n ± 0%   5.338n ± 0%   +1.04% (p=0.000 n=50)
memmove/178        5.299n ± 0%   5.337n ± 0%   +0.71% (p=0.000 n=50)
memmove/179        5.296n ± 0%   5.343n ± 0%   +0.88% (p=0.000 n=50)
memmove/180        5.292n ± 0%   5.343n ± 0%   +0.97% (p=0.000 n=50)
memmove/181        5.303n ± 0%   5.335n ± 0%   +0.60% (p=0.000 n=50)
memmove/182        5.305n ± 0%   5.338n ± 0%   +0.62% (p=0.000 n=50)
memmove/183        5.298n ± 0%   5.329n ± 0%   +0.59% (p=0.000 n=50)
memmove/184        5.299n ± 0%   5.333n ± 0%   +0.64% (p=0.000 n=50)
memmove/185        5.291n ± 0%   5.330n ± 0%   +0.73% (p=0.000 n=50)
memmove/186        5.296n ± 0%   5.332n ± 0%   +0.68% (p=0.000 n=50)
memmove/187        5.297n ± 0%   5.320n ± 0%   +0.44% (p=0.000 n=50)
memmove/188        5.286n ± 0%   5.314n ± 0%   +0.53% (p=0.000 n=50)
memmove/189        5.293n ± 0%   5.318n ± 0%   +0.46% (p=0.000 n=50)
memmove/190        5.294n ± 0%   5.318n ± 0%   +0.45% (p=0.000 n=50)
memmove/191        5.292n ± 0%   5.314n ± 0%   +0.40% (p=0.032 n=50)
memmove/192        5.272n ± 0%   5.304n ± 0%   +0.60% (p=0.000 n=50)
memmove/193        5.279n ± 0%   5.310n ± 0%   +0.57% (p=0.000 n=50)
memmove/194        5.294n ± 0%   5.308n ± 0%   +0.26% (p=0.018 n=50)
memmove/195        5.302n ± 0%   5.311n ± 0%   +0.18% (p=0.010 n=50)
memmove/196        5.301n ± 0%   5.316n ± 0%   +0.28% (p=0.023 n=50)
memmove/197        5.302n ± 0%   5.327n ± 0%   +0.47% (p=0.000 n=50)
memmove/198        5.310n ± 0%   5.326n ± 0%   +0.30% (p=0.003 n=50)
memmove/199        5.303n ± 0%   5.319n ± 0%   +0.30% (p=0.009 n=50)
memmove/200        5.312n ± 0%   5.330n ± 0%   +0.35% (p=0.001 n=50)
memmove/201        5.307n ± 0%   5.333n ± 0%   +0.50% (p=0.000 n=50)
memmove/202        5.311n ± 0%   5.334n ± 0%   +0.44% (p=0.000 n=50)
memmove/203        5.313n ± 0%   5.335n ± 0%   +0.41% (p=0.006 n=50)
memmove/204        5.312n ± 0%   5.332n ± 0%   +0.36% (p=0.002 n=50)
memmove/205        5.318n ± 0%   5.345n ± 0%   +0.50% (p=0.000 n=50)
memmove/206        5.311n ± 0%   5.333n ± 0%   +0.42% (p=0.002 n=50)
memmove/207        5.310n ± 0%   5.338n ± 0%   +0.52% (p=0.000 n=50)
memmove/208        5.319n ± 0%   5.341n ± 0%   +0.40% (p=0.004 n=50)
memmove/209        5.330n ± 0%   5.346n ± 0%   +0.30% (p=0.004 n=50)
memmove/210        5.329n ± 0%   5.349n ± 0%   +0.38% (p=0.002 n=50)
memmove/211        5.318n ± 0%   5.340n ± 0%   +0.41% (p=0.000 n=50)
memmove/212        5.339n ± 0%   5.343n ± 0%        ~ (p=0.396 n=50)
memmove/213        5.329n ± 0%   5.343n ± 0%   +0.25% (p=0.017 n=50)
memmove/214        5.339n ± 0%   5.358n ± 0%   +0.35% (p=0.035 n=50)
memmove/215        5.342n ± 0%   5.346n ± 0%        ~ (p=0.063 n=50)
memmove/216        5.338n ± 0%   5.359n ± 0%   +0.39% (p=0.002 n=50)
memmove/217        5.341n ± 0%   5.362n ± 0%   +0.39% (p=0.015 n=50)
memmove/218        5.354n ± 0%   5.373n ± 0%   +0.36% (p=0.041 n=50)
memmove/219        5.352n ± 0%   5.362n ± 0%        ~ (p=0.143 n=50)
memmove/220        5.344n ± 0%   5.370n ± 0%   +0.50% (p=0.001 n=50)
memmove/221        5.345n ± 0%   5.373n ± 0%   +0.53% (p=0.000 n=50)
memmove/222        5.348n ± 0%   5.360n ± 0%   +0.23% (p=0.014 n=50)
memmove/223        5.354n ± 0%   5.377n ± 0%   +0.43% (p=0.024 n=50)
memmove/224        5.352n ± 0%   5.363n ± 0%        ~ (p=0.052 n=50)
memmove/225        5.372n ± 0%   5.380n ± 0%        ~ (p=0.481 n=50)
memmove/226        5.368n ± 0%   5.386n ± 0%   +0.34% (p=0.004 n=50)
memmove/227        5.386n ± 0%   5.402n ± 0%   +0.29% (p=0.028 n=50)
memmove/228        5.400n ± 0%   5.408n ± 0%        ~ (p=0.174 n=50)
memmove/229        5.423n ± 0%   5.427n ± 0%        ~ (p=0.444 n=50)
memmove/230        5.411n ± 0%   5.429n ± 0%   +0.33% (p=0.020 n=50)
memmove/231        5.420n ± 0%   5.433n ± 0%   +0.24% (p=0.034 n=50)
memmove/232        5.435n ± 0%   5.441n ± 0%        ~ (p=0.235 n=50)
memmove/233        5.446n ± 0%   5.462n ± 0%        ~ (p=0.590 n=50)
memmove/234        5.467n ± 0%   5.461n ± 0%        ~ (p=0.921 n=50)
memmove/235        5.472n ± 0%   5.478n ± 0%        ~ (p=0.883 n=50)
memmove/236        5.466n ± 0%   5.478n ± 0%        ~ (p=0.324 n=50)
memmove/237        5.471n ± 0%   5.489n ± 0%        ~ (p=0.132 n=50)
memmove/238        5.485n ± 0%   5.489n ± 0%        ~ (p=0.460 n=50)
memmove/239        5.484n ± 0%   5.488n ± 0%        ~ (p=0.833 n=50)
memmove/240        5.483n ± 0%   5.495n ± 0%        ~ (p=0.095 n=50)
memmove/241        5.498n ± 0%   5.514n ± 0%        ~ (p=0.077 n=50)
memmove/242        5.518n ± 0%   5.517n ± 0%        ~ (p=0.481 n=50)
memmove/243        5.514n ± 0%   5.511n ± 0%        ~ (p=0.503 n=50)
memmove/244        5.510n ± 0%   5.497n ± 0%   -0.24% (p=0.038 n=50)
memmove/245        5.516n ± 0%   5.505n ± 0%        ~ (p=0.317 n=50)
memmove/246        5.513n ± 1%   5.494n ± 0%        ~ (p=0.147 n=50)
memmove/247        5.518n ± 0%   5.499n ± 0%   -0.36% (p=0.011 n=50)
memmove/248        5.503n ± 0%   5.492n ± 0%        ~ (p=0.267 n=50)
memmove/249        5.498n ± 0%   5.497n ± 0%        ~ (p=0.765 n=50)
memmove/250        5.485n ± 0%   5.493n ± 0%        ~ (p=0.348 n=50)
memmove/251        5.503n ± 0%   5.482n ± 0%   -0.37% (p=0.013 n=50)
memmove/252        5.497n ± 0%   5.485n ± 0%        ~ (p=0.077 n=50)
memmove/253        5.489n ± 0%   5.496n ± 0%        ~ (p=0.850 n=50)
memmove/254        5.497n ± 0%   5.491n ± 0%        ~ (p=0.548 n=50)
memmove/255        5.484n ± 1%   5.494n ± 0%        ~ (p=0.888 n=50)
memmove/256        6.952n ± 0%   7.676n ± 0%  +10.41% (p=0.000 n=50)
geomean            4.406n        4.127n        -6.33%
```

[libc] Change the GPU to use builtin memory functions (#68003)

2023-10-04T12:02:55+00:00

Summary:
The GPU build is special in the sense that we always know that
up-to-date `clang` is always going to be the compiler. This allows us to
rely directly on builtins, which allow us to push a lot of this
complexity into the backend. Backend implementations are favored on
the GPU because it allows us to do a lot more target specific
optimizations. This patch changes over the common memory functions to
use builtin versions when building for AMDGPU or NVPTX.

[libc] Mass replace enclosing namespace (#67032)

2023-09-26T09:45:04+00:00

This is step 4 of
https://discourse.llvm.org/t/rfc-customizable-namespace-to-allow-testing-the-libc-when-the-system-libc-is-also-llvms-libc/73079

llvm-project.git/libc/src/string/memory_utils/inline_memmove.h, branch users/nico/python-2