Commit Graph

12 Commits

Author SHA1 Message Date
Nikita Popov 176bbcae11 [DSE] Remove MemDep-based implementation
The MemorySSA-based implementation has been enabled without issue
for a while now, so keeping the old implementation around doesn't
seem useful anymore. This drops the MemDep-based implementation.

Differential Revision: https://reviews.llvm.org/D97877
2021-03-07 18:17:31 +01:00
Florian Hahn 6cb54cfe0b [DSE] Move legacy tests to DeadStoreElimination/MemDepAnalysis.
This patch moves the tests for the old MemDepAnalysis based DSE
implementation to the MemDepAnalysis subdirectory and updates them to
pass -enable-dse-memoryssa=false.

This is in preparation for the switch to MemorySSA-backed DSE.
2020-09-04 14:38:03 +01:00
Florian Hahn ab86e64a96 [DSE] Remove some dead code from DSE tests.
Some tests depend on DSE removing dead instructions unrelated to any
memory optimization. That's not really DSE's job, remove it.
2020-09-04 09:39:40 +01:00
Eli Friedman 11aa3707e3 StoreInst should store Align, not MaybeAlign
This is D77454, except for stores.  All the infrastructure work was done
for loads, so the remaining changes necessary are relatively small.

Differential Revision: https://reviews.llvm.org/D79968
2020-05-15 12:26:58 -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
Shiva Chen 2c864551df [DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.
In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
name, the function label belong, line number in the file, and the
address label located. In order to keep these information in LLVM
IR and to allow backend to generate debug information correctly.
We create a new kind of metadata for labels, DILabel. The format
of DILabel is

!DILabel(scope: !1, name: "foo", file: !2, line: 3)

We hope to keep debug information as much as possible even the
code is optimized. So, we create a new kind of intrinsic for label
metadata to avoid the metadata is eliminated with basic block.
The intrinsic will keep existing if we keep it from optimized out.
The format of the intrinsic is

llvm.dbg.label(metadata !1)

It has only one argument, that is the DILabel metadata. The
intrinsic will follow the label immediately. Backend could get the
label metadata through the intrinsic's parameter.

We also create DIBuilder API for labels to be used by Frontend.
Frontend could use createLabel() to allocate DILabel objects, and use
insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR.

Differential Revision: https://reviews.llvm.org/D45024

Patch by Hsiangkai Wang.

llvm-svn: 331841
2018-05-09 02:40:45 +00:00
Sanjay Patel 1aef27f5cd [DSE] make sure memory is not modified before partial store merging (PR36129)
We missed a critical check in D30703. We must make sure that no intermediate 
store is sitting between the stores that we want to merge.

This should fix:
https://bugs.llvm.org/show_bug.cgi?id=36129

Differential Revision: https://reviews.llvm.org/D42663

llvm-svn: 323759
2018-01-30 13:53:59 +00:00
Sanjay Patel d023a9b777 [DSE] add test for PR36129; NFC
We can miscompile because we're not checking is the memory might
me modified between the seemingly redundant store ops.

llvm-svn: 323704
2018-01-29 22:50:08 +00:00
Sanjay Patel 1d04b5bacf [DSE] Merge stores when the later store only writes to memory locations the early store also wrote to (2nd try)
This is a 2nd attempt at:
https://reviews.llvm.org/rL310055
...which was reverted at rL310123 because of PR34074:
https://bugs.llvm.org/show_bug.cgi?id=34074

In this version, we break out of the inner loop after we successfully merge and kill a pair of stores. In the
earlier rev, we were continuing instead, which meant we could process the invalid info from a now dead store.

Original commit message (authored by Filipe Cabecinhas):

This fixes PR31777.

If both stores' values are ConstantInt, we merge the two stores
(shifting the smaller store appropriately) and replace the earlier (and
larger) store with an updated constant.

In the future we should also support vectors of integers. And maybe
float/double if we can.  

Differential Revision: https://reviews.llvm.org/D30703

llvm-svn: 314206
2017-09-26 13:54:28 +00:00
Nico Weber 69ca5322d4 Revert r310055, it caused PR34074.
llvm-svn: 310123
2017-08-04 20:40:38 +00:00
Filipe Cabecinhas fb9d2a8775 [DSE] Merge stores when the later store only writes to memory locations the early store also wrote to.
Summary:
This fixes PR31777.

If both stores' values are ConstantInt, we merge the two stores
(shifting the smaller store appropriately) and replace the earlier (and
larger) store with an updated constant.

In the future we should also support vectors of integers. And maybe
float/double if we can.

Reviewers: hfinkel, junbuml, jfb, RKSimon, bkramer

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D30703

llvm-svn: 310055
2017-08-04 12:28:36 +00:00