Commit Graph

8 Commits

Author SHA1 Message Date
Vedant Kumar 099bffe7f7 Revert "[CodeExtractor] Don't create bitcasts when inserting lifetime markers (NFCI)"
This reverts commit 26ee8aff2b.

It's necessary to insert bitcast the pointer operand of a lifetime
marker if it has an opaque pointer type.

rdar://70560161
2020-10-22 12:25:50 -07:00
Hans Wennborg 0628bea513 Revert "[PM/CC1] Add -f[no-]split-cold-code CC1 option to toggle splitting"
This broke Chromium's PGO build, it seems because hot-cold-splitting got turned
on unintentionally. See comment on the code review for repro etc.

> This patch adds -f[no-]split-cold-code CC1 options to clang. This allows
> the splitting pass to be toggled on/off. The current method of passing
> `-mllvm -hot-cold-split=true` to clang isn't ideal as it may not compose
> correctly (say, with `-O0` or `-Oz`).
>
> To implement the -fsplit-cold-code option, an attribute is applied to
> functions to indicate that they may be considered for splitting. This
> removes some complexity from the old/new PM pipeline builders, and
> behaves as expected when LTO is enabled.
>
> Co-authored by: Saleem Abdulrasool <compnerd@compnerd.org>
> Differential Revision: https://reviews.llvm.org/D57265
> Reviewed By: Aditya Kumar, Vedant Kumar
> Reviewers: Teresa Johnson, Aditya Kumar, Fedor Sergeev, Philip Pfaffe, Vedant Kumar

This reverts commit 273c299d5d.
2020-10-19 12:31:14 +02:00
Vedant Kumar 273c299d5d [PM/CC1] Add -f[no-]split-cold-code CC1 option to toggle splitting
This patch adds -f[no-]split-cold-code CC1 options to clang. This allows
the splitting pass to be toggled on/off. The current method of passing
`-mllvm -hot-cold-split=true` to clang isn't ideal as it may not compose
correctly (say, with `-O0` or `-Oz`).

To implement the -fsplit-cold-code option, an attribute is applied to
functions to indicate that they may be considered for splitting. This
removes some complexity from the old/new PM pipeline builders, and
behaves as expected when LTO is enabled.

Co-authored by: Saleem Abdulrasool <compnerd@compnerd.org>
Differential Revision: https://reviews.llvm.org/D57265
Reviewed By: Aditya Kumar, Vedant Kumar
Reviewers: Teresa Johnson, Aditya Kumar, Fedor Sergeev, Philip Pfaffe, Vedant Kumar
2020-10-15 23:13:33 +00:00
Vedant Kumar 26ee8aff2b [CodeExtractor] Don't create bitcasts when inserting lifetime markers (NFCI)
Lifetime marker intrinsics support any pointer type, so CodeExtractor
does not need to bitcast to `i8*` in order to use these markers.
2020-09-29 16:34:36 -07:00
Eric Christopher cee313d288 Revert "Temporarily Revert "Add basic loop fusion pass.""
The reversion apparently deleted the test/Transforms directory.

Will be re-reverting again.

llvm-svn: 358552
2019-04-17 04:52:47 +00:00
Eric Christopher a863435128 Temporarily Revert "Add basic loop fusion pass."
As it's causing some bot failures (and per request from kbarton).

This reverts commit r358543/ab70da07286e618016e78247e4a24fcb84077fda.

llvm-svn: 358546
2019-04-17 02:12:23 +00:00
Vedant Kumar 5f5cac3ae2 [CodeExtractor] Do not lift lifetime.end markers for region inputs
If a lifetime.end marker occurs along one path through the extraction
region, but not another, then it's still incorrect to lift the marker,
because there is some path through the extracted function which would
ordinarily not reach the marker. If the call to the extracted function
is in a loop, unrolling can cause inputs to the function to become
optimized out as undef after the first iteration.

To prevent incorrect stack slot merging in the calling function, it
should be sufficient to lift lifetime.start markers for region inputs.
I've tested this theory out by doing a stage2 check-all with randomized
splitting enabled.

This is a follow-up to r353973, and there's additional context for this
change in https://reviews.llvm.org/D57834.

rdar://47896986

Differential Revision: https://reviews.llvm.org/D58253

llvm-svn: 354159
2019-02-15 18:46:58 +00:00
Vedant Kumar 4b0cc9a7c8 [CodeExtractor] Only lift lifetime markers present in the extraction region
When CodeExtractor finds liftime markers referencing inputs to the
extraction region, it lifts these markers out of the region and inserts
them around the call to the extracted function (see r350420, PR39671).

However, it should *only* lift lifetime markers that are actually
present in the extraction region. I.e., if a start marker is present in
the extraction region but a corresponding end marker isn't (or vice
versa), only the start marker (or end marker, resp.) should be lifted.

Differential Revision: https://reviews.llvm.org/D57834

llvm-svn: 353973
2019-02-13 19:53:38 +00:00