[libc][docs] Update implementation status tables for Memory and String Functions.

[lntue]

Summary

Update implementation status tables for Memory and String Functions to include other targets.

[sivachandra]

In general, I think just listing every target architecture for every function is not scalable. I think we should separate platform independent implementations from platform specific implementations. The platform independent implementations are straightforward to list. We can include the tables only for platform specific implementations. For items like the optimized memory functions, I think we can say something like this:

Platform independent, tiny, byte-by-byte implementations of `memcpy`, ... are available for size sensitive embedded and bare-metal platforms. For performance sensitive use cases, optimized flavors for x86_64, aarch64 and riscv64 are also available.

libc/docs/strings.rst

56

What is barebone-aarch32?

69

Should this be aarch32 or the more popular term Arm32?

[lntue]

In D151822#4384998, @sivachandra wrote:

In general, I think just listing every target architecture for every function is not scalable. I think we should separate platform independent implementations from platform specific implementations. The platform independent implementations are straightforward to list. We can include the tables only for platform specific implementations. For items like the optimized memory functions, I think we can say something like this:

Platform independent, tiny, byte-by-byte implementations of `memcpy`, ... are available for size sensitive embedded and bare-metal platforms. For performance sensitive use cases, optimized flavors for x86_64, aarch64 and riscv64 are also available.

I think for the status page, we do need the list of currently available functions / entry points for each officially supported platform. It helps us to quickly identify holes in our entrypoints.txt files as you can see in the lists. As long as we keep the platform classification generic enough, I don't think it will grow too much more. And these tables should be updated whenever there are changes in entrypoints.txt files.

For further implementation / optimization details, we can totally add to another sections or pages, but I think they should be separated from our concrete supported entrypoints.txt status.

[lntue]

Address comments

[gchatelet]

Could the listing be automated with a script + presubmit hook?

[lntue]

In D151822#4386231, @gchatelet wrote:

Could the listing be automated with a script + presubmit hook?

That would be ideal. Do you suggestion of how it could be done?

libc/docs/strings.rst

-   The tests are located at:
     ``libc/test/src/stdlib``, and
     ``libc/test/src/__support``
     respectively.
 
 ---------------------
 Implementation Status
 ---------------------
 
-Primary memory functions
-========================
+* To check functions enabled for Linux:
 
-.. TODO(gchatelet): add details about the memory functions.
+  - `linux-x86_64 <https://github.com/llvm/llvm-project/tree/main/libc/config/linux/x86_64/entrypoints.txt>`_
 
+  - `linux-aarch64 <https://github.com/llvm/llvm-project/tree/main/libc/config/linux/aarch64/entrypoints.txt>`_
 
-=============  =========
-Function Name  Available
-=============  =========
-bzero          |check|
-bcmp           |check|
-bcopy          |check|       
-memcpy         |check|
-memset         |check|
-memcmp         |check|
-memmove        |check|
-=============  =========
+  - `linux-aarch32 <https://github.com/llvm/llvm-project/tree/main/libc/config/linux/arm/entrypoints.txt>`_
 
+  - `linux-riscv64 <https://github.com/llvm/llvm-project/tree/main/libc/config/linux/riscv64/entrypoints.txt>`_
 
-Other Raw Memory Functions
-==========================
+* To check functions enabled for Windows:
 
-=============  =========
-Function Name  Available
-=============  =========
-memchr         |check|
-memrchr        |check|
-memccpy        |check|
-mempcpy        |check|
-=============  =========
+  - `windows-x86_64 <https://github.com/llvm/llvm-project/tree/main/libc/config/windows/entrypoints.txt>`_ 
 
-String Memory Functions
-=======================
+  - windows-aarch64 - to be added
 
-=============  =========
-Function Name  Available
-=============  =========
-stpcpy         |check|
-stpncpy        |check|
-strcpy         |check|
-strncpy        |check|
-strcat         |check|
-strncat        |check|
-strdup         |check|
-strndup        |check|
-=============  =========
+* To check functions enabled for macOS:
 
-String Examination Functions
-============================
+  - `darwin-x86_64 <https://github.com/llvm/llvm-project/tree/main/libc/config/darwin/x86_64/entrypoints.txt>`_
+
+  - `darwin-aarch64 <https://github.com/llvm/llvm-project/tree/main/libc/config/darwin/arm/entrypoints.txt>`_
+
+* To check functions enabled for GPU:
+
+  - `gpu-entrypoints <https://github.com/llvm/llvm-project/tree/main/libc/config/gpu/entrypoints.txt>`_ 
+
+* To check functions enabled for embedded system:
+
+  - `embedded-aarch32 <https://github.com/llvm/llvm-project/tree/main/libc/config/baremetal/arm/entrypoints.txt>`_ 
+
+  - embedded-riscv32 - to be added
+
+
+Memory Functions
+================
+
+.. TODO(gchatelet): add details about the memory functions.
+
++------------+---------------------------------------+-------------------+-------------------+-------------------+-------------------+
+| <Func>     |  Linux                                | Windows           | MacOS             | Embedded          | GPU               |
+|            +---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+|            | x86_64  | aarch64 | aarch32 | riscv64 | x86_64  | aarch64 | x86_64  | aarch64 | arm32   | riscv32 | AMD     | nVidia  |
++============+=========+=========+=========+=========+=========+=========+=========+=========+=========+=========+=========+=========+
+| bcopy      | |check| | |check| | |check| | |check| | |check| |         |         | |check| | |check| |         |         |         |
++------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| bcmp       | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| bzero      | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| memccpy    | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| memchr     | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| memcmp     | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| memcpy     | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| memmem     | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| memmove    | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| mempccpy   | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| memrchr    | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| memset     | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+
+
+String Functions
+=======================
+
++---------------+---------------------------------------+-------------------+-------------------+-------------------+-------------------+
+| <Func>        |  Linux                                | Windows           | MacOS             | Embedded          | GPU               |
+|               +---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+|               | x86_64  | aarch64 | aarch32 | riscv64 | x86_64  | aarch64 | x86_64  | aarch64 | arm32   | riscv32 | AMD     | nVidia  |
++===============+=========+=========+=========+=========+=========+=========+=========+=========+=========+=========+=========+=========+
+| index         | |check| | |check| | |check| | |check| |         |         |         |         |         |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| rindex        | |check| | |check| | |check| | |check| |         |         |         |         |         |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| stpcpy        | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| stpncpy       | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strcasecmp    | |check| | |check| | |check| | |check| | |check| |         |         | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strcasestr    | |check| | |check| | |check| | |check| | |check| |         |         | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strcat        | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strchr        | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strchrnul     | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strcmp        | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strcoll       | |check| |         |         | |check| |         |         |         |         |         |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strcpy        | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strcspn       | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strdup        | |check| | |check| |         | |check| | |check| |         | |check| | |check| |         |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strerror      | |check| | |check| |         | |check| |         |         |         |         |         |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strerror_r    | |check| | |check| |         | |check| |         |         |         |         |         |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strerror_s    |         |         |         |         |         |         |         |         |         |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strerrorlen_s |         |         |         |         |         |         |         |         |         |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strlcat       | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strlcpy       | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strlen        | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strncasecmp   | |check| | |check| | |check| | |check| | |check| |         |         | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strncat       | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strncmp       | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strncpy       | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strndup       | |check| | |check| |         | |check| | |check| |         | |check| | |check| |         |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strnlen       | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strpbrk       | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strrchr       | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strsep        | |check| | |check| | |check| | |check| |         |         |         |         |         |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strsignal     | |check| | |check| |         | |check| |         |         |         |         |         |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strspn        | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strstr        | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strtok        | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strtok_r      | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         | |check| | |check| |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strxfrm       | |check| |         |         | |check| |         |         |         |         |         |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
 
-=============  =========
-Function Name  Available
-=============  =========
-strlen         |check|
-strnlen        |check|
-strcmp         |check|
-strncmp        |check|
-strchr         |check|
-strrchr        |check|
-strspn         |check|
-strcspn        |check|
-strpbrk        |check|
-strstr         |check|
-strtok         |check|
-strtok_r       |check|
-=============  =========
 
 String Conversion Functions
 ============================
 
 These functions are not in strings.h, but are still primarily string
 functions, and are therefore tracked along with the rest of the string
 functions.
 
 The String to float functions were implemented using the Eisel-Lemire algorithm 
 (read more about the algorithm here: `The Eisel-Lemire ParseNumberF64 Algorithm
 <https://nigeltao.github.io/blog/2020/eisel-lemire.html>`_). This improved
 the performance of string to float and double, and allowed it to complete this
 comprehensive test 15% faster than glibc: `Parse Number FXX Test Data
 <https://github.com/nigeltao/parse-number-fxx-test-data>`_. The test was done 
 with LLVM-libc built on 2022-04-14 and Debian GLibc version 2.33-6. The targets
 ``libc_str_to_float_comparison_test`` and 
 ``libc_system_str_to_float_comparison_test`` were built and run on the test data
 10 times each, skipping the first run since it was an outlier.
 
 
-=============  =========
-Function Name  Available
-=============  =========
-atof           |check|
-atoi           |check|
-atol           |check|
-atoll          |check|
-strtol         |check|
-strtoll        |check|
-strtoul        |check|
-strtoull       |check|
-strtof         |check|
-strtod         |check|
-strtold        |check|
-strtoimax      |check|
-strtoumax      |check|
-=============  =========
++---------------+---------------------------------------+-------------------+-------------------+-------------------+-------------------+
+| <Func>        |  Linux                                | Windows           | MacOS             | Embedded          | GPU               |
+|               +---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+|               | x86_64  | aarch64 | aarch32 | riscv64 | x86_64  | aarch64 | x86_64  | aarch64 | arm32   | riscv32 | AMD     | nVidia  |
++===============+=========+=========+=========+=========+=========+=========+=========+=========+=========+=========+=========+=========+
+| atof          | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| atoi          | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| atol          | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| atoll         | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strtof        | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strtod        | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strtold       | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strtol        | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strtoll       | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strtoul       | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strtoull      | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strtoimax     | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
+| strtoumax     | |check| | |check| | |check| | |check| | |check| |         | |check| | |check| | |check| |         |         |         |
++---------------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+
 
-String Error Functions
-======================
-
-=============  =========
-Function Name  Available
-=============  =========
-strerror
-strerror_s
-strerrorlen_s
-=============  =========
 
 Localized String Functions
 ==========================
 
 These functions require locale.h, and will be added when locale support is 
 implemented in LLVM-libc.
 
 =============  =========