Commit Graph

15 Commits

Author SHA1 Message Date
Michael Kruse 0c6c555beb Fix Memory Access of failing tests.
Mark scalar dependences for different statements belonging to same BB
as 'Inter'.

Contributed-by: Nandini Singhal <cs15mtech01004@iith.ac.in>

Differential Revision: https://reviews.llvm.org/D37147

llvm-svn: 312324
2017-09-01 11:36:52 +00:00
Tobias Grosser 2307f86c47 [ForwardOpTree] Allow forwarding in the presence of region statements
Summary:
After region statements now also have instruction lists, this is a
straightforward extension.

Reviewers: Meinersbur, bollu, singam-sanjay, gareevroman

Reviewed By: Meinersbur

Subscribers: hfinkel, pollydev, llvm-commits

Tags: #polly

Differential Revision: https://reviews.llvm.org/D37298

llvm-svn: 312249
2017-08-31 16:04:49 +00:00
Michael Kruse 1046aa3148 [VirtualInstruction] Handle MetadataAsValue as constant.
The complication of bspatch.cc of the AOSP buildbot currently fails
presumably because the occurance of a MetadataAsValue in an operand.
This kind of value can occur as operands of intrinsics, the typical
example being the debug intrinsics.

Polly currently ignores the debug intrinsics and it is not yet clear
which other intrinic might occur. For such cases, and to unbreak the
AOSP buildbot, treat a MetadataAsValue as a constant because it can be
referenced without modification in generated code.

llvm-svn: 309992
2017-08-03 22:00:01 +00:00
Michael Kruse 672c011460 [VirtualInstruction] Avoid use of getStmtFor(BB). NFC.
With this patch, we get rid of the last use of getStmtFor(BB). Here
this is done by getting the last statement of the incoming block in
case the user is a phi node; otherwise just fetching the statement
comprising the instruction for which the virtual use is being created.

Differential Revision: https://reviews.llvm.org/D36268

llvm-svn: 309947
2017-08-03 15:27:00 +00:00
Michael Kruse 8e41d2baab [Simplify] Do not remove dependencies of phis within region stmts.
These were wrongly assumed to be phi nodes that require
MemoryKind::PHI accesses.

llvm-svn: 309454
2017-07-28 23:22:32 +00:00
Michael Kruse fd7f40961b [VirtualInstruction] Do not iterate over a region statement's instruction list. NFC.
It should be empty anyways. In this case it would even be redundant
because we just all all instructions in region statements.

llvm-svn: 309453
2017-07-28 23:22:23 +00:00
Michael Kruse a508a4e619 [ScopBuilder/Simplify] Refactor isEscaping. NFC.
ScopBuilder and Simplify (through VirtualInstruction.cpp) previously
used this functionality in their own implementation. Refactor them
both into a common one into the Scop class.

BlockGenerator also makes use of a similiar functionality, but also
records outside users and takes place after region simplification.
Merging it as well would be more complicated.

llvm-svn: 309273
2017-07-27 14:39:52 +00:00
Michael Kruse 8a8aca4299 [Simplify] Count PHINodes in simplifiable exit nodes as escaping use.
After region exit simplification, the incoming block of a phi node in
the SCoP region's exit block lands outside of the region. Since we
treat SCoPs as if this already happened, we need to account for that
when looking for outside uses of scalars (i.e. escaping scalars).

llvm-svn: 309271
2017-07-27 14:09:31 +00:00
Michael Kruse 95b39da8ae [Simplify] Fix invalid removal write for escaping values.
A PHI node's incoming block is the user of its operand, not the PHI's parent.

Assuming the PHINode's parent being the user lead to the removal of a
MemoryAccesses because its use was assumed to be inside of the SCoP.

llvm-svn: 309164
2017-07-26 19:58:15 +00:00
Michael Kruse 8d89179e33 [ScopInfo] Rename ScopStmt::contains(BB) to represents(BB). NFC.
In future, there will be no more a 1:1 correspondence between statements
and basic blocks, the name `contains` does not correctly capture their
relationship. A BB may infact comprise of multiple statements; hence we
describe a statement 'representing' a basic block.

Differential Revision: https://reviews.llvm.org/D35838

llvm-svn: 308982
2017-07-25 16:25:37 +00:00
Michael Kruse e186013149 Annotate dump() functions with LLVM_DUMP_METHOD. NFC.
llvm-svn: 308749
2017-07-21 15:54:13 +00:00
Michael Kruse 22058c3fbb [Simplify] Remove unused instructions and accesses.
Use a mark-and-sweep algorithm to find and remove unused instructions
and MemoryAccesses. This is useful in particular to remove scalar
writes that are never used anywhere. A scalar write in a loop induces
a write-after-write dependency that stops the loop iterations to be
rescheduled. Such writes can be a result of previous transformations
such as DeLICM and operand tree forwarding.

It adds a new class VirtualInstruction that represents an instruction in
a particular statement. At the moment an instruction can only belong to
the statement that represents a BasicBlock. In the future, instructions
can be in one of multiple statements representing a BasicBlock
(Nandini's work), in different statements than its BasicBlock would
indicate, and even multiple statements at once (by forwarding operand
trees). It also integrates nicely with the VirtualUse class.

ScopStmt::contains(Instruction*) currently uses the instruction's parent
BasicBlock to check whether it contains the instruction. It will need to
check the actual statement list when one of the aforementioned features
become possible.

Differential Revision: https://reviews.llvm.org/D35656

llvm-svn: 308626
2017-07-20 16:21:55 +00:00
Michael Kruse 89da6bbcb4 Make byref llvm::Use parameters const. NFC.
llvm-svn: 308522
2017-07-19 20:41:56 +00:00
Michael Kruse bfaa1857b3 [VirtualInstruction] Do a lookup instead of a linear search. NFC.
llvm-svn: 302837
2017-05-11 22:56:27 +00:00
Michael Kruse eedae7630a Introduce VirtualUse. NFC.
If a ScopStmt references a (scalar) value, there are multiple
possibilities where this value can come. The decision about what kind of
use it is must be handled consistently at different places, which can be
error-prone. VirtualUse is meant to centralize the handling of the
different types of value uses.

This patch makes ScopBuilder and CodeGeneration use VirtualUse. This
already helps to show inconsistencies with the value handling. In order
to keep this patch NFC, exceptions to the general rules are added.
These might be fixed later if they turn to problems. Overall, this
should result in fewer post-codegen IR-verification errors, but instead
assertion failures in `getNewValue` that are closer to the actual error.

Differential Revision: https://reviews.llvm.org/D32667

llvm-svn: 302157
2017-05-04 15:22:57 +00:00