Commit Graph

7 Commits

Author SHA1 Message Date
Sam Parker 1c3ca61294 [ARM][ParallelDSP] Change smlad insertion order
Instead of inserting everything after the 'root' of the reduction,
insert all instructions as close to their operands as possible. This
can help reduce register pressure.

Differential Revision: https://reviews.llvm.org/D67392

llvm-svn: 374981
2019-10-16 09:37:03 +00:00
QingShan Zhang bb8d540010 [TableGen] Fix a bug that MCSchedClassDesc is interfered between different SchedModel
Assume that, ModelA has scheduling resource for InstA and ModelB has scheduling resource for InstB. This is what the llvm::MCSchedClassDesc looks like:

llvm::MCSchedClassDesc ModelASchedClasses[] = {
...
InstA, 0, ...
InstB, -1,...
};

llvm::MCSchedClassDesc ModelBSchedClasses[] = {
...
InstA, -1,...
InstB, 0,...
};
The -1 means invalid num of macro ops, while it is valid if it is >=0. This is what we look like now:

llvm::MCSchedClassDesc ModelASchedClasses[] = {
...
InstA, 0, ...
InstB, 0,...
};

llvm::MCSchedClassDesc ModelBSchedClasses[] = {
...
InstA, 0,...
InstB, 0,...
};
And compiler hit the assertion here because the SCDesc is valid now for both InstA and InstB.

Differential Revision: https://reviews.llvm.org/D67950

llvm-svn: 374524
2019-10-11 08:36:54 +00:00
David Green 120a5e9a74 [ARM] Cortex-M4 schedule additions
This is an attempt to fill in some of the missing instructions from the
Cortex-M4 schedule, and make it easier to do the same for other ARM cpus.

- Some instructions are marked as hasNoSchedulingInfo as they are pseudos or
  otherwise do not require scheduling info
- A lot of features have been marked not supported
- Some WriteRes's have been added for cvt instructions.
- Some extra instruction latencies have been added, notably by relaxing the
  regex for dsp instruction to catch more cases, and some fp instructions.

This goes a long way to get the CompleteModel working for this CPU. It does not
go far enough as to get all scheduling info for all output operands correct.

Differential Revision: https://reviews.llvm.org/D67957

llvm-svn: 373163
2019-09-29 08:38:48 +00:00
Sam Parker 17ea9b463c [NFC][ARM] Add and modify tests
Add test for ParallelDSP.

llvm-svn: 371594
2019-09-11 08:17:48 +00:00
Sam Parker f82d4ed771 [ARM] Remove EarlyCSE from backend
There is an issue with early CSE hitting an assert, so temporarily
remove the pass from the Arm backend.
    
Bug: https://bugs.llvm.org/show_bug.cgi?id=41081

Differential Revision: https://reviews.llvm.org/D59410

llvm-svn: 356259
2019-03-15 13:36:37 +00:00
Sam Parker 9e73020bfa [ARM][ParallelDSP] Disable for big-endian
Bail early when we don't have a preheader and also if the target is
big endian because it's written with only little endian in mind!

Differential Revision: https://reviews.llvm.org/D59368

llvm-svn: 356243
2019-03-15 10:19:32 +00:00
Sam Parker 4c4ff13d3c [ARM][ParallelDSP] Enable multiple uses of loads
When choosing whether a pair of loads can be combined into a single
wide load, we check that the load only has a sext user and that sext
also only has one user. But this can prevent the transformation in
the cases when parallel macs use the same loaded data multiple times.
    
To enable this, we need to fix up any other uses after creating the
wide load: generating a trunc and a shift + trunc pair to recreate
the narrow values. We also need to keep a record of which loads have
already been widened.

Differential Revision: https://reviews.llvm.org/D59215

llvm-svn: 356132
2019-03-14 11:14:13 +00:00