[libc] Enable the 'div' routines on the GPU

[jhuber6]

Summary

This patch simply enables the div, ldiv, and, lldiv functions on
the GPU. This should be straightforward enough.

[JonChesterfield]

Is this sufficient to run the associated tests or do we need some cmake as well?

[jdoerfert]

do we have tests?

[jhuber6]

In D154143#4461397, @JonChesterfield wrote:

Is this sufficient to run the associated tests or do we need some cmake as well?

The tests already exist, they are enabled conditionally by whether or not the entrypoint is present int entrypoints.txt, like this does. So yes, it adds three new tests.

libc/config/gpu/api.td

 include "config/public_api.td"
 
 include "spec/stdc.td"
 include "spec/gpu_ext.td"
 
 def StringAPI : PublicAPI<"string.h"> {
   let Types = ["size_t"];
 }
 
 def StdlibAPI : PublicAPI<"stdlib.h"> {
   let Types = [
+    "div_t",
+    "ldiv_t",
+    "lldiv_t",
     "size_t",
     "__atexithandler_t",
   ];
 }
 
 def FenvAPI: PublicAPI<"fenv.h"> {
   let Types = ["fenv_t"];
 }

libc/config/gpu/entrypoints.txt

set(TARGET_LIBC_ENTRYPOINTS
     libc.src.string.strtok_r
 
     # stdlib.h entrypoints
     libc.src.stdlib.abs
     libc.src.stdlib.atoi
     libc.src.stdlib.atof
     libc.src.stdlib.atol
     libc.src.stdlib.atoll
+    libc.src.stdlib.div
     libc.src.stdlib.labs
+    libc.src.stdlib.ldiv
     libc.src.stdlib.llabs
+    libc.src.stdlib.lldiv
     libc.src.stdlib.strtod
     libc.src.stdlib.strtof
     libc.src.stdlib.strtol
     libc.src.stdlib.strtold
     libc.src.stdlib.strtoll
     libc.src.stdlib.strtoul
     libc.src.stdlib.strtoull
 

libc/docs/gpu/support.rst

 abs            |check|
 atoi           |check|
 atof           |check|
 atol           |check|
 atoll          |check|
 exit           |check|    |check|
 labs           |check|
 llabs          |check|
+div            |check|
+ldiv           |check|
+lldiv          |check|
 strtod         |check|
 strtof         |check|
 strtol         |check|
 strtold        |check|
 strtoll        |check|
 strtoul        |check|
 strtoull       |check|
 =============  =========  ============