58 Commits

Author SHA1 Message Date
Michael Kruse
54071126d8 [ForwardOpTree] Properly indent enumeration in comment. NFC.
llvm-svn: 308887
2017-07-24 15:34:03 +00:00
Michael Kruse
67752076bc [ForwardOpTree] Rename FD_CanForward to FD_CanForwardLeaf. NFC.
To make the meaning and distinction to FD_CanForwardTree clearer.

llvm-svn: 308886
2017-07-24 15:33:58 +00:00
Michael Kruse
d85e345ce0 [ForwardOpTree] Add comments to ForwardingDecision items. NFC.
In particular, explain the difference between FD_CanForward
and FD_CanForwardTree.

llvm-svn: 308885
2017-07-24 15:33:53 +00:00
Michael Kruse
07e8c36dc7 [ForwardOpTree] Support read-only value uses.
Read-only values (values defined before the SCoP) require special
handing with -polly-analyze-read-only-scalars=true (which is the
default). If active, each use of a value requires a read access.
When a copied value uses a read-only value, we must also ensure that
such a MemoryAccess is available or is created.

Differential Revision: https://reviews.llvm.org/D35764

llvm-svn: 308876
2017-07-24 12:43:27 +00:00
Michael Kruse
5b8a9095e8 [ForwardOpTree] Fix mixup in comment. NFC.
The cases DoIt==false and DoIt==true were mixed up.

Thanks to Siddharth for noticing.

llvm-svn: 308874
2017-07-24 12:39:46 +00:00
Michael Kruse
25a688165b [ScopInfo] Fix typo in method name. NFC.
prependInstrunction -> prependInstruction

Thanks Nandini for noticing.

llvm-svn: 308873
2017-07-24 12:39:41 +00:00
Michael Kruse
e5f4706a55 [ForwardOpTree] Support hoisted invariant loads.
Hoisted loads can be trivially supported because there are no
MemoryAccess to be modified, the loaded value is just available
at code generation.

llvm-svn: 308826
2017-07-22 14:30:02 +00:00
Michael Kruse
a6b2de3b59 [ForwardOpTree] Introduce the -polly-optree pass.
This pass 'forwards' operand trees into statements that use them in
order to avoid scalar dependencies.

This minimal implementation handles only the case of speculatable
instructions. We will successively add support for:
- Hoisted loads
- Read-only values
- Synthesizable values
- Loads
- PHIs
- Forwarding only parts of the tree

Differential Revision: https://reviews.llvm.org/D35754

llvm-svn: 308825
2017-07-22 14:02:47 +00:00