summaryrefslogtreecommitdiffstats
path: root/llvm/test/Transforms/HotColdSplit/split-cold-2.ll
Commit message (Collapse)AuthorAgeFilesLines
* Revert "Temporarily Revert "Add basic loop fusion pass.""Eric Christopher2019-04-171-0/+37
| | | | | | | | The reversion apparently deleted the test/Transforms directory. Will be re-reverting again. llvm-svn: 358552
* Temporarily Revert "Add basic loop fusion pass."Eric Christopher2019-04-171-37/+0
| | | | | | | | As it's causing some bot failures (and per request from kbarton). This reverts commit r358543/ab70da07286e618016e78247e4a24fcb84077fda. llvm-svn: 358546
* [HotColdSplit] Introduce a cost model to control splitting behaviorVedant Kumar2019-01-251-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The main goal of the model is to avoid *increasing* function size, as that would eradicate any memory locality benefits from splitting. This happens when: - There are too many inputs or outputs to the cold region. Argument materialization and reloads of outputs have a cost. - The cold region has too many distinct exit blocks, causing a large switch to be formed in the caller. - The code size cost of the split code is less than the cost of a set-up call. A secondary goal is to prevent excessive overall binary size growth. With the cost model in place, I experimented to find a splitting threshold that works well in practice. To make warm & cold code easily separable for analysis purposes, I moved split functions to a "cold" section. I experimented with thresholds between [0, 4] and set the default to the threshold which minimized geomean __text size. Experiment data from building LNT+externals for X86 (N = 639 programs, all sizes in bytes): | Configuration | __text geom size | __cold geom size | TEXT geom size | | **-Os** | 1736.3 | 0, n=0 | 10961.6 | | -Os, thresh=0 | 1740.53 | 124.482, n=134 | 11014 | | -Os, thresh=1 | 1734.79 | 57.8781, n=90 | 10978.6 | | -Os, thresh=2 | ** 1733.85 ** | 65.6604, n=61 | 10977.6 | | -Os, thresh=3 | 1733.85 | 65.3071, n=61 | 10977.6 | | -Os, thresh=4 | 1735.08 | 67.5156, n=54 | 10965.7 | | **-Oz** | 1554.4 | 0, n=0 | 10153 | | -Oz, thresh=2 | ** 1552.2 ** | 65.633, n=61 | 10176 | | **-O3** | 2563.37 | 0, n=0 | 13105.4 | | -O3, thresh=2 | ** 2559.49 ** | 71.1072, n=61 | 13162.4 | Picking thresh=2 reduces the geomean __text section size by 0.14% at -Os, -Oz, and -O3 and causes ~0.2% growth in the TEXT segment. Note that TEXT size is page-aligned, whereas section sizes are byte-aligned. Experiment data from building LNT+externals for ARM64 (N = 558 programs, all sizes in bytes): | Configuration | __text geom size | __cold geom size | TEXT geom size | | **-Os** | 1763.96 | 0, n=0 | 42934.9 | | -Os, thresh=2 | ** 1760.9 ** | 76.6755, n=61 | 42934.9 | Picking thresh=2 reduces the geomean __text section size by 0.17% at -Os and causes no growth in the TEXT segment. Measurements were done with D57082 (r352080) applied. Differential Revision: https://reviews.llvm.org/D57125 llvm-svn: 352228
* [HotColdSplit] Simplify tests by lowering their splitting thresholdsVedant Kumar2019-01-171-2/+2
| | | | | | | | This gets rid of the brittle/mysterious calls to @sink()/@sideeffect() peppered throughout the test cases. They are no longer needed to force splitting to occur. llvm-svn: 351480
* [CodeExtractor] Mark functions noreturn when applicableVedant Kumar2018-11-081-0/+3
| | | | | | | | | | This eliminates the outlining penalty for llvm.trap/unreachable, because callers no longer have to emit cleanup/ret instructions after calling an outlined `noreturn` function. rdar://45523626 llvm-svn: 346421
* [hot-cold-split] Name split functions with ".cold" suffixTeresa Johnson2018-10-241-2/+2
| | | | | | | | | | | | | | | | | | | | | | | Summary: The current default of appending "_"+entry block label to the new extracted cold function breaks demangling. Change the deliminator from "_" to "." to enable demangling. Because the header block label will be empty for release compile code, use "extracted" after the "." when the label is empty. Additionally, add a mechanism for the client to pass in an alternate suffix applied after the ".", and have the hot cold split pass use "cold."+Count, where the Count is currently 1 but can be used to uniquely number multiple cold functions split out from the same function with D53588. Reviewers: sebpop, hiraditya Subscribers: llvm-commits, erik.pilkington Differential Revision: https://reviews.llvm.org/D53534 llvm-svn: 345178
* [hot-cold-split] Add opt remark on successTeresa Johnson2018-10-221-2/+3
| | | | | | | | | | | | Summary: Emit optimization remark on successful hot cold split. Reviewers: sebpop, hiraditya Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D53512 llvm-svn: 344938
* [hot-cold-split] Add missing FileCheck invocationsTeresa Johnson2018-10-221-2/+2
| | | | | | | | | | | | | | Summary: r344558 added some CHECK statements to split-cold-2.ll, but didn't add any invocations of FileCheck. Add those here. Reviewers: sebpop Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D53505 llvm-svn: 344928
* [hot-cold-split] fix failing testcasesSebastian Pop2018-10-161-1/+1
| | | | llvm-svn: 344577
* [hot-cold-split] fix static analysis of cold regionsSebastian Pop2018-10-151-0/+4
| | | | | | | | | | | | | | | | | | | | | | Make the code of blockEndsInUnreachable to match the function blockEndsInUnreachable in CodeGen/BranchFolding.cpp. I also have added a note to make sure the code of this function will not be modified unless the back-end version is also modified. An early return before outlining has been added to avoid outlining the full function body when the first block in the function is marked cold. The static analysis of cold code has been amended to avoid marking the whole function as cold by back-propagation because the back-propagation would mark blocks with return statements as cold. The patch adds debug statements to help discover these problems. Differential Revision: https://reviews.llvm.org/D52904 llvm-svn: 344558
* Add support for new pass managerAditya Kumar2018-10-031-0/+1
| | | | | | | | | | | Modified the testcases to use both pass managers Use single commandline flag for both pass managers. Differential Revision: https://reviews.llvm.org/D52708 Reviewers: sebpop, tejohnson, brzycki, SirishP Reviewed By: tejohnson, brzycki llvm-svn: 343662
* HotColdSplit: fix invalid SSA due to outliningSebastian Pop2018-09-141-0/+28
The test used to fail with an invalid phi node: the two predecessors were outlined and the SSA representation was left invalid. The patch adds the exit block to the cold region. llvm-svn: 342277
OpenPOWER on IntegriCloud