16 Commits

Author SHA1 Message Date
Mingjie Xu
fac9472593
[IR] Reland Optimize PHINode::removeIncomingValue() and PHINode::removeIncomingValueIf() to use the swapping strategy. (#174274)
Reland #171963, #172639 and #173444, they are reverted in
86b9f90b9574b3a7d15d28a91f6316459dcfa046 because of introducing
non-determinism in compiles.
The non-determinism has been fixed in
9b8addffa70cee5b2acc5454712d9cf78ce45710.
2026-01-04 09:24:53 +08:00
Walter Lee
86b9f90b95
Revert 159f1c048e08a8780d92858cfc80e723c90235e3 (#173893)
This causes non-determinism in compiles.

From nikic: "FYI the non-determinism is also visible on
llvm-opt-benchmark. Maybe repeatedly running test cases from
299446d99f
could reproduce the issue..."

Also revert dependent 796fafeff92fe5d2d20594859e92607116e30a16 and
e135447bda617125688b71d33480d131d1076a72.
2025-12-29 20:23:13 -05:00
Mingjie Xu
159f1c048e
[IR] Optimize PHINode::removeIncomingValue() by swapping removed incoming value with the last incoming value. (#171963)
Current implementation uses `std::copy` to shift all incoming values
after the removed index. This patch optimizes
`PHINode::removeIncomingValue()` by replacing the linear shift of
incoming values with a swap-with-last strategy.

After this change, the relative order of incoming values after removal
is not preserved.

This improves compile-time for PHI nodes with many predecessors.

Depends:
https://github.com/llvm/llvm-project/pull/171955
https://github.com/llvm/llvm-project/pull/171956
https://github.com/llvm/llvm-project/pull/171960
https://github.com/llvm/llvm-project/pull/171962
2025-12-17 19:44:01 +08:00
Yingwei Zheng
2071ea24a2
[LVI] Skip self loops in solveBlockValueNonLocal (#127763)
We cannot infer more information from backedges in
`solveBlockValueNonLocal`. However, since DT is unavailable in LVI,
there is not a precise way to check whether a BB edge is a backedge.
This patch only skips self loops to unblock the range analysis.

The motivating case is extracted from
https://github.com/llvm/llvm-project/pull/127663.

Compile-time impact is high:
https://llvm-compile-time-tracker.com/compare.php?from=84ddda58c870681dd12ed765e9d59d5e00567f94&to=af032f1351358f2f5b5d9f4e87c5601c23b9bd37&stat=instructions:u
2025-02-23 17:52:38 +08:00
Lee Wei
ead9ad2960
[llvm] Remove br i1 undef from some regression tests [NFC] (#116739)
This PR removes tests with br i1 undef under
`llvm/tests/Transforms/JumpThreading, LCSSA, LICM, LoopDeletion,
LoopIdiom`.
2024-11-19 08:12:25 +00:00
Nikita Popov
963a2ebef8 [JumpThreading] Regenerate test checks (NFC) 2024-01-09 15:09:17 +01:00
Matt Arsenault
b6909fe9ca JumpThreading: Modernize some test checking
Stop using tests with grep, or no output checks at all. Just use
FileCheck and generate checks. Also remove unnecessary requires
asserts.
2022-11-27 12:41:28 -05:00
Matt Arsenault
07e34d2de5 JumpThreading: Convert tests to -passes 2022-11-27 11:19:28 -05:00
Matt Arsenault
83d5052768 JumpThreading: Convert tests to opaque pointers
phi-known.ll:test2 required deleting one manual check for a bitcast

Also strip trailing whitespace while we're touching everything.
2022-11-27 11:19:28 -05:00
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
Brian M. Rzycki
9b7ae23256 [JumpThreading] Preservation of DT and LVI across the pass
Summary:
See D37528 for a previous (non-deferred) version of this
patch and its description.

Preserves dominance in a deferred manner using a new class
DeferredDominance. This reduces the performance impact of
updating the DominatorTree at every edge insertion and
deletion. A user may call DDT->flush() within JumpThreading
for an up-to-date DT. This patch currently has one flush()
at the end of runImpl() to ensure DT is preserved across
the pass.

LVI is also preserved to help subsequent passes such as
CorrelatedValuePropagation. LVI is simpler to maintain and
is done immediately (not deferred). The code to perform the
preversation was minimally altered and simply marked as
preserved for the PassManager to be informed.

This extends the analysis available to JumpThreading for
future enhancements such as threading across loop headers.

Reviewers: dberlin, kuhar, sebpop

Reviewed By: kuhar, sebpop

Subscribers: mgorny, dmgreen, kuba, rnk, rsmith, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D40146

llvm-svn: 322401
2018-01-12 21:06:48 +00:00
Reid Kleckner
cd78ddc119 Revert "[JumpThreading] Preservation of DT and LVI across the pass"
This reverts r321825, it causes crashes in Chromium. Reproducer
forthcoming.

llvm-svn: 321832
2018-01-04 23:23:46 +00:00
Brian M. Rzycki
cdad6c0b60 [JumpThreading] Preservation of DT and LVI across the pass
Summary:
See D37528 for a previous (non-deferred) version of this
patch and its description.

Preserves dominance in a deferred manner using a new class
DeferredDominance. This reduces the performance impact of
updating the DominatorTree at every edge insertion and
deletion. A user may call DDT->flush() within JumpThreading
for an up-to-date DT. This patch currently has one flush()
at the end of runImpl() to ensure DT is preserved across
the pass.

LVI is also preserved to help subsequent passes such as
CorrelatedValuePropagation. LVI is simpler to maintain and
is done immediately (not deferred). The code to perfom the
preversation was minimally altered and was simply marked
as preserved for the PassManager to be informed.

This extends the analysis available to JumpThreading for
future enhancements. One example is loop boundary threading.

Reviewers: dberlin, kuhar, sebpop

Reviewed By: kuhar, sebpop

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D40146

llvm-svn: 321825
2018-01-04 21:57:32 +00:00
Brian M. Rzycki
580bc3c8fa Reverting [JumpThreading] Preservation of DT and LVI across the pass
Stage 2 bootstrap failed:
http://lab.llvm.org:8011/builders/clang-x86_64-linux-selfhost-modules-2/builds/14434

llvm-svn: 320641
2017-12-13 22:01:17 +00:00
Brian M. Rzycki
d989af98b3 [JumpThreading] Preservation of DT and LVI across the pass
Summary:
See D37528 for a previous (non-deferred) version of this
patch and its description.

Preserves dominance in a deferred manner using a new class
DeferredDominance. This reduces the performance impact of
updating the DominatorTree at every edge insertion and
deletion. A user may call DDT->flush() within JumpThreading
for an up-to-date DT. This patch currently has one flush()
at the end of runImpl() to ensure DT is preserved across
the pass.

LVI is also preserved to help subsequent passes such as
CorrelatedValuePropagation. LVI is simpler to maintain and
is done immediately (not deferred). The code to perfom the
preversation was minimally altered and was simply marked
as preserved for the PassManager to be informed.

This extends the analysis available to JumpThreading for
future enhancements. One example is loop boundary threading.

Reviewers: dberlin, kuhar, sebpop

Reviewed By: kuhar, sebpop

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D40146

llvm-svn: 320612
2017-12-13 20:52:26 +00:00