[libc-commits] [libc] Add definitions to embedded AArch32/AArch64 (PR #142597)

[via libc-commits]

https://github.com/saturn691 created https://github.com/llvm/llvm-project/pull/142597

Add `CLOCKS_PER_SEC` and the older `CLK_TCK`. Allows the user to define a `__CLK_TCK` to override if necessary.

Also add an extra column for embedded AArch64 in `time.rst`

>From 7e2c2b63fb95bdb2b934afc20e88f026a4a0138f Mon Sep 17 00:00:00 2001
From: William Huynh <William.Huynh at arm.com>
Date: Tue, 3 Jun 2025 13:56:16 +0100
Subject: [PATCH] Add definitions to embedded AArch32/AArch64

---
 libc/docs/headers/time.rst                  | 132 ++++++++++----------
 libc/include/llvm-libc-macros/time-macros.h |   9 ++
 2 files changed, 76 insertions(+), 65 deletions(-)

diff --git a/libc/docs/headers/time.rst b/libc/docs/headers/time.rst
index de82d80a2bec4..9733a176fbb25 100644
--- a/libc/docs/headers/time.rst
+++ b/libc/docs/headers/time.rst
@@ -42,72 +42,74 @@ Implementation Status
 
 * To check date and time functions enabled for embedded system:
 
+  - `barebone-aarch64 <https://github.com/llvm/llvm-project/tree/main/libc/config/baremetal/aarch64/entrypoints.txt>`_
+
   - `barebone-aarch32 <https://github.com/llvm/llvm-project/tree/main/libc/config/baremetal/arm/entrypoints.txt>`_
 
   - barebone-riscv32 - to be added
 
-+---------------------+-----------------------------------------------+-------------------+-------------------+-------------------+-------------------+
-| <Func>              |  Linux                                        | Windows           | MacOS             | Embedded          | GPU               |
-|                     +---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-|                     | x86_64  | aarch64 | aarch32 | riscv64/riscv32 | x86_64  | aarch64 | x86_64  | aarch64 | aarch32 | riscv32 | AMD     | nVidia  |
-+=====================+=========+=========+=========+=================+=========+=========+=========+=========+=========+=========+=========+=========+
-| asctime             | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| asctime_r           | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| ctime               | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| ctime_r             | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| clock               | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| clock_getcpuclockid |         |         |         |                 |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| clock_getres        |         |         |         |                 |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| clock_gettime       | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| clock_nanosleep     |         |         |         |                 |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| clock_settime       |         |         |         |                 |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| ctime               |         |         |         |                 |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| ctime_r             |         |         |         |                 |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| difftime            | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| getdate             |         |         |         |                 |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| gettimeofday        | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| gmtime              | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| gmtime_r            | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| localtime           |         |         |         |                 |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| localtime_r         |         |         |         |                 |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| mktime              | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| nanosleep           | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| strftime            |         |         |         |                 |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| strptime            |         |         |         |                 |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| time                | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| timer_create        |         |         |         |                 |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| timer_delete        |         |         |         |                 |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| timer_gettime       |         |         |         |                 |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| timer_getoverrun    |         |         |         |                 |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| timer_settime       |         |         |         |                 |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
-| tzset               |         |         |         |                 |         |         |         |         |         |         |         |         |
-+---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
++---------------------+-----------------------------------------------+-------------------+-------------------+-----------------------------+---------+---------+
+| <Func>              |  Linux                                        | Windows           | MacOS             | Embedded                    | GPU               |
+|                     +---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+|                     | x86_64  | aarch64 | aarch32 | riscv64/riscv32 | x86_64  | aarch64 | x86_64  | aarch64 | aarch64 | aarch32 | riscv32 | AMD     | nVidia  |
++=====================+=========+=========+=========+=================+=========+=========+=========+=========+=========+=========+=========+=========+=========+
+| asctime             | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| asctime_r           | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| ctime               | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| ctime_r             | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| clock               | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| clock_getcpuclockid |         |         |         |                 |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| clock_getres        |         |         |         |                 |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| clock_gettime       | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| clock_nanosleep     |         |         |         |                 |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| clock_settime       |         |         |         |                 |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| ctime               |         |         |         |                 |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| ctime_r             |         |         |         |                 |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| difftime            | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| getdate             |         |         |         |                 |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| gettimeofday        | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| gmtime              | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| gmtime_r            | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| localtime           |         |         |         |                 |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| localtime_r         |         |         |         |                 |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| mktime              | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| nanosleep           | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strftime            |         |         |         |                 |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strptime            |         |         |         |                 |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| time                | |check| | |check| |         |     |check|     |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| timer_create        |         |         |         |                 |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| timer_delete        |         |         |         |                 |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| timer_gettime       |         |         |         |                 |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| timer_getoverrun    |         |         |         |                 |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| timer_settime       |         |         |         |                 |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| tzset               |         |         |         |                 |         |         |         |         |         |         |         |         |         |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
\ No newline at end of file
diff --git a/libc/include/llvm-libc-macros/time-macros.h b/libc/include/llvm-libc-macros/time-macros.h
index 445d8b3e837ed..d5b71605aaf12 100644
--- a/libc/include/llvm-libc-macros/time-macros.h
+++ b/libc/include/llvm-libc-macros/time-macros.h
@@ -5,7 +5,16 @@
 #include "gpu/time-macros.h"
 #elif defined(__linux__)
 #include "linux/time-macros.h"
+#elif defined(__arm__) || defined(_M_ARM) || defined(__aarch64__)
+#ifdef __CLK_TCK
+#define CLOCKS_PER_SEC __CLK_TCK
+#else
+// Semihosting uses centiseconds as default
+#define CLOCKS_PER_SEC 100
 #endif
+#endif
+
+#define CLK_TCK CLOCKS_PER_SEC
 
 #define TIME_UTC 1
 #define TIME_MONOTONIC 2