Commit Graph

13 Commits

Author SHA1 Message Date
Roman Lebedev 60286818ff
[Analysis] Update Analysis/LazyValueAnalysis/lvi-after-jumpthreading.ll
I should have updated it in 1f665046fb
but i didn't even realize those tests were there.
2019-10-23 18:39:10 +03:00
John Regehr 3a1c9d55cc [LVI] run transfer function for binary operator even when the RHS isn't a constant
LVI was symbolically executing binary operators only when the RHS was
constant, missing the case where we have a ConstantRange for the RHS,
but not an actual constant. Tested using check-all and by
bootstrapping. Compile time is not impacted measurably.

Differential Revision: https://reviews.llvm.org/D19859

llvm-svn: 347379
2018-11-21 05:24:12 +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
Daniel Jasper 0a51ec29c9 Revert r314435: "[JumpThreading] Preserve DT and LVI across the pass"
Causes a segfault on a builtbot (and in our internal bootstrapping of
Clang). See Eli's response on the commit thread.

llvm-svn: 314589
2017-09-30 11:57:19 +00:00
Evandro Menezes 3701df55c6 [JumpThreading] Preserve DT and LVI across the pass
JumpThreading now preserves dominance and lazy value information across the
entire pass.  The pass manager is also informed of this preservation with
the goal of DT and LVI being recalculated fewer times overall during
compilation.

This change prepares JumpThreading for enhanced opportunities; particularly
those across loop boundaries.

Patch by: Brian Rzycki <b.rzycki@samsung.com>,
          Sebastian Pop <s.pop@samsung.com>

Differential revision: https://reviews.llvm.org/D37528

llvm-svn: 314435
2017-09-28 17:24:40 +00:00
Davide Italiano 01cb947abb [JumpThreading] Add an option to dump LazyValueInfo after the run.
Differential Revision:  https://reviews.llvm.org/D35973

llvm-svn: 309353
2017-07-28 02:57:43 +00:00
Anna Thomas 7949f4529a [JumpThreading][LVI] Invalidate LVI information after blocks are merged
Summary:
After a single predecessor is merged into a basic block, we need to invalidate
the LVI information for the new merged block, when LVI is not provably true for
all of instructions in the new block.
The test cases added show the correct LVI information using the LVI printer
pass.

Reviewers: reames, dberlin, davide, sanjoy

Reviewed by: dberlin, davide

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D34108

llvm-svn: 305699
2017-06-19 15:23:33 +00:00
Anna Thomas 4acfc7e16e [LVI Printer] Rely on the LVI analysis functions rather than the LVI cache
Summary:
LVIPrinter pass was previously relying on the LVICache. We now directly call the
the LVI functions which solves the value if the LVI information is not already
available in the cache. This has 2 benefits over the printing of LVI cache:
1. higher coverage (i.e. catches errors) in LVI code when cache value is
invalidated.
2. relies on the core functions, and not dependent on the LVI cache (which may
be scrapped at some point).
It would still catch any cache invalidation errors, since we first go through
the cache.

Reviewers: reames, dberlin, sanjoy

Reviewed by: reames

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D32135

llvm-svn: 304819
2017-06-06 19:25:31 +00:00
Anna Thomas e27b39a976 [LVI] Add an LVI printer pass to capture test LVI cache after transformations
Summary:
Adding a printer pass for printing the LVI cache values after transformations
that use LVI.
This will help us in identifying cases where LVI
invariants are violated, or transforms that leave LVI in an incorrect state.
Right now, I have added two test cases to show that the printer pass is working.
I will be adding more test cases in a later change, once this change is
checked in upstream.

Reviewers: reames, dberlin, sanjoy, apilipenko

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D30790

llvm-svn: 298542
2017-03-22 19:27:12 +00:00