Commit Graph

23 Commits

Author SHA1 Message Date
Jakob Stoklund Olesen
16c11feb5a Add tags to live interval unions to avoid using stale queries.
The tag is updated whenever the live interval union is changed, and it is tested
before using cached information.

llvm-svn: 125224
2011-02-09 21:52:03 +00:00
Jakob Stoklund Olesen
ed53ab1635 Replace TargetRegisterInfo::printReg with a PrintReg class that also works without a TRI instance.
Print virtual registers numbered from 0 instead of the arbitrary
FirstVirtualRegister. The first virtual register is printed as %vreg0.
TRI::NoRegister is printed as %noreg.

llvm-svn: 123107
2011-01-09 03:05:53 +00:00
Jakob Stoklund Olesen
6498db2c8c Avoid dereferencing end() in collectInterferingVRegs() when there is no
interference.

llvm-svn: 122108
2010-12-17 23:16:38 +00:00
Jakob Stoklund Olesen
40f23cd5ca Provide LiveIntervalUnion::Query::checkLoopInterference.
This is a three-way interval list intersection between a virtual register, a
live interval union, and a loop. It will be used to identify interference-free
loops for live range splitting.

llvm-svn: 122034
2010-12-17 04:09:47 +00:00
Jakob Stoklund Olesen
1811e4cb20 Start using SplitKit and MachineLoopRanges in RegAllocGreedy in preparation of
live range splitting around loops guided by register pressure.

So far, trySplit() simply prints a lot of debug output.

llvm-svn: 121918
2010-12-15 23:46:13 +00:00
Jakob Stoklund Olesen
c13ce4748e Add LiveIntervalUnion print methods, RegAllocGreedy::trySplit debug spew.
llvm-svn: 121783
2010-12-14 19:38:49 +00:00
Jakob Stoklund Olesen
c5ad05ca30 Use TRI::printReg instead of AbstractRegisterDescription when printing
LiveIntervalUnions.

llvm-svn: 121781
2010-12-14 18:53:47 +00:00
Jakob Stoklund Olesen
5bb5c67227 Add a forgotten initializer for CheckedFirstInterference.
llvm-svn: 121410
2010-12-09 21:20:44 +00:00
Andrew Trick
ec37b93b07 Added register reassignment prototype to RAGreedy. It's a simple
heuristic to reshuffle register assignments when we can't find an
available reg.

llvm-svn: 121388
2010-12-09 18:15:21 +00:00
Jakob Stoklund Olesen
17b2e8c293 IntervalMap iterators are heavyweight, so avoid copying them around and use
references instead.

Similarly, IntervalMap::begin() is almost as expensive as find(), so use find(x)
instead of begin().advanceTo(x);

This makes RegAllocBasic run another 5% faster.

llvm-svn: 121344
2010-12-09 01:06:52 +00:00
Jakob Stoklund Olesen
ffc0f6586a Properly deal with empty intervals when checking for interference.
llvm-svn: 121319
2010-12-08 23:51:35 +00:00
Jakob Stoklund Olesen
9d6472e894 Switch LiveIntervalUnion from std::set to IntervalMap.
This speeds up RegAllocBasic by 20%, not counting releaseMemory which becomes
way faster.

llvm-svn: 121201
2010-12-07 23:18:47 +00:00
Andrew Trick
a2cec41172 Comment typo.
llvm-svn: 120504
2010-11-30 23:59:50 +00:00
Andrew Trick
89dd5f7eac Coding style. No significant functionality. Abandon linear scan style
in favor of the widespread llvm style. Capitalize variables and add
newlines for visual parsing. Rename variables for readability.
And other cleanup.

llvm-svn: 120490
2010-11-30 23:18:47 +00:00
Andrew Trick
9d60f59b55 RABasic is nearly functionally complete. There are a few remaining
benchmarks hitting an assertion.
Adds LiveIntervalUnion::collectInterferingVRegs.
Fixes "late spilling" by checking for any unspillable live vregs among
all physReg aliases.

llvm-svn: 118701
2010-11-10 19:18:47 +00:00
Andrew Trick
374490bf92 Adds RABasic verification and tracing.
(retry now that the windows build is green)

llvm-svn: 118630
2010-11-09 21:04:34 +00:00
Andrew Trick
6b9d6df8c3 Reverting r118604. Windows build broke.
llvm-svn: 118613
2010-11-09 19:47:51 +00:00
Andrew Trick
ce7b5df15e Adds RABasic verification and tracing.
llvm-svn: 118604
2010-11-09 19:01:17 +00:00
Andrew Trick
45ec210e3c Adds support for spilling previously allocated live intervals to
handle cases in which a register is unavailable for spill code.
Adds LiveIntervalUnion::extract. While processing interferences on a
live virtual register, reuses the same Query object for each
physcial reg.

llvm-svn: 118423
2010-11-08 18:02:08 +00:00
Andrew Trick
6363e80ded Remove the vector of live vregs. I thought we would need to track
them, but hopefully we won't. And this is not the right data structure
to do it anyway.

llvm-svn: 117412
2010-10-26 22:58:24 +00:00
Andrew Trick
06fb7ed472 Jakob's review of the basic register allocator.
llvm-svn: 117384
2010-10-26 18:34:01 +00:00
Chandler Carruth
25324e76ae Fix a likely bug in an assertion by adding parentheses around '||'. This bug
was found by a GCC warning. ;]

llvm-svn: 117199
2010-10-23 07:46:14 +00:00
Andrew Trick
7a1dadd47d This is a prototype of an experimental register allocation
framework. It's purpose is not to improve register allocation per se,
but to make it easier to develop powerful live range splitting. I call
it the basic allocator because it is as simple as a global allocator
can be but provides the building blocks for sophisticated register
allocation with live range splitting. 

A minimal implementation is provided that trivially spills whenever it
runs out of registers. I'm checking in now to get high-level design
and style feedback. I've only done minimal testing. The next step is
implementing a "greedy" allocation algorithm that does some register
reassignment and makes better splitting decisions.

llvm-svn: 117174
2010-10-22 23:09:15 +00:00