tree 349be9a25c764fe3a07557852306aaa514a89cdd
parent 940fa351ca886282af4faa3572b94c1720d9ef93
author Michael Kruse <llvm-project@meinersbur.de> 1632643579 -0500
committer Copybara-Service <copybara-worker@google.com> 1632645320 -0700

[Polly] Remove isConstCall.

The function was intended to catch OpenMP functions such as
get_thread_id(). If matched, the call would be considered synthesizable.

There were a few problems with this:

 * get_thread_id() is not 'const' in the sense of have the gcc manual
   defines it: "do not examine any values except their arguments".
   get_thread_id() reads OpenCL runtime libreary global state.
   What was inteded was probably 'speculable'.

 * isConstCall was implemented using mayReadOrWriteMemory(). 'const' is
   stricter than that, mayReadOrWriteMemory is e.g. true for malloc(),
   since it may only read/write addresses that are considered
   inaccessible fro the application. However, malloc is certainly not
   speculable.

 * Values that are isConstCall were not handled consistently throughout
   Polly. In particular, it was not considered for referenced values
   (OpenMP outlining and PollyACC).

Fix by removing special handling for isConstCall entirely.

GitOrigin-RevId: 1cea25eec90e355c9b072edc1b6e1e9903d7bca4