Commit Graph

9 Commits

Author SHA1 Message Date
Stefan Stipanovic a516fbac52 [Attributor] Use nofree argument attribute for heap-to-stack conversion
Reviewers: jdoerfert, uenoku

Subscribers:

Differential Revision: https://reviews.llvm.org/D70140
2019-11-17 21:35:04 +01:00
Stefan Stipanovic f35740d6e9 NoFree argument attribute.
Summary: Deducing nofree atrribute for function arguments.

Reviewers: jdoerfert

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67886
2019-11-02 19:40:48 +01:00
Stefan Stipanovic 5fb1782918 Revert "NoFree argument attribute."
This reverts commit c12efa2ed0.
2019-11-02 17:31:02 +01:00
Stefan Stipanovic c12efa2ed0 NoFree argument attribute.
Summary: Deducing nofree atrribute for function arguments.

Reviewers: jdoerfert

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67886
2019-11-02 16:35:38 +01:00
Johannes Doerfert c36e2ebf9f [Attributor][NFCI] Avoid unnecessary work except for testing
Trying to deduce information for declarations and calls sites of
declarations is not useful in practice but only for testing. Add a flag
that disables this by default but also enable it in the tests.

The misc.ll test will verify the flag "works" as expected.
2019-11-02 00:28:24 -05:00
Johannes Doerfert 0be9cf2da9 [Attributor] Add "free"-based heap2stack deduction
Summary:
If there is a unique free of the allocated that has to be reached from
the malloc, we can apply the heap-2-stack transformation even if the
pointer escapes.

Reviewers: hfinkel, sstefan1, uenoku

Subscribers: hiraditya, bollu, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68958
2019-10-30 20:57:57 -05:00
Johannes Doerfert af6e479733 [Attributor][FIX] Ensure h2s doesn't trigger on escaped pointers
We do not yet perform h2s because we know something is free'ed but we do
it because we know the pointer does not escape. Storing the pointer
allows it to escape so we have to prevent that.

llvm-svn: 374699
2019-10-13 04:14:15 +00:00
Johannes Doerfert d20f80780e [Attributor][FIX] Do not apply h2s for arbitrary mallocs
H2S did apply to mallocs of non-constant sizes if the uses were OK. This
is now forbidden through reording of the "good" and "bad" cases in the
conditional.

llvm-svn: 374698
2019-10-13 03:54:08 +00:00
Stefan Stipanovic 431141c5cc [Attributor] Heap-To-Stack Conversion
D53362 gives a prototype heap-to-stack conversion pass. With addition of new attributes in the attributor, this can now be revisted and improved. This will place it in the Attributor to make it easier to use new attributes (eg. nofree, nosync, willreturn, etc.) and other attributor features.

Reviewers: jdoerfert, uenoku, hfinkel, efriedma

Subscribers: lebedev.ri, xbolva00, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D65408

llvm-svn: 371942
2019-09-15 21:47:41 +00:00