aboutsummaryrefslogtreecommitdiff
path: root/lib/CodeGen/RegAllocGreedy.cpp
AgeCommit message (Collapse)Author
2011-02-03Temporarily revert 124765 in an attempt to find the cycle breaking bootstrap.Eric Christopher
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124778 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-03Defer SplitKit value mapping until all defs are available.Jakob Stoklund Olesen
The greedy register allocator revealed some problems with the value mapping in SplitKit. We would sometimes start mapping values before all defs were known, and that could change a value from a simple 1-1 mapping to a multi-def mapping that requires ssa update. The new approach collects all defs and register assignments first without filling in any live intervals. Only when finish() is called, do we compute liveness and mapped values. At this time we know with certainty which values map to multiple values in a split range. This also has the advantage that we can compute live ranges based on the remaining uses after rematerializing at split points. The current implementation has many opportunities for compile time optimization. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124765 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-20SplitKit requires that all defs are in place before calling useIntv().Jakob Stoklund Olesen
The value mapping gets confused about which original values have multiple new definitions so they may need phi insertions. This could probably be simplified by letting enterIntvBefore() take a live range to be added following the instruction. As long as the range stays inside the same basic block, value mapping shouldn't be a problem. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123926 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-19Don't accidentally leave small gaps in the live ranges when leaving the activeJakob Stoklund Olesen
interval after an instruction. The leaveIntvAfter() method only adds liveness from the instruction's boundary index to the inserted copy. Ideally, SplitKit should be smarter about this, perhaps by combining useIntv() and leaveIntvAfter() into one method that guarantees continuity. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123858 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-19Implement RAGreedy::splitAroundRegion and remove loop splitting.Jakob Stoklund Olesen
Region splitting includes loop splitting as a subset, and it is more generic. The splitting heuristics for variables that are live in more than one block are now: 1. Try to create a region that covers multiple basic blocks. 2. Try to create a new live range for each block with multiple uses. 3. Spill. Steps 2 and 3 are similar to what the standard spiller is doing. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123853 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-18Add RAGreedy methods for splitting live ranges around regions.Jakob Stoklund Olesen
Analyze the live range's behavior entering and leaving basic blocks. Compute an interference pattern for each allocation candidate, and use SpillPlacement to find an optimal region where that register can be live. This code is still not enabled. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123774 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-28Pacify the compiler. BestWeight cannot in fact be used uninitializedDuncan Sands
in this function, but the compiler was warning that it might be when doing a release build. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122595 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-22When RegAllocGreedy decides to spill the interferences of the current register,Jakob Stoklund Olesen
pick the victim with the lowest total spill weight. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122445 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-18Tweak debug spew.Jakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122132 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-18Fix GCC warning:Nick Lewycky
lib/CodeGen/RegAllocGreedy.cpp:311: error: unused variable 'PhysReg' [-Wunused-variable] git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122122 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-18Pass a Banner argument to the machine code verifier both fromJakob Stoklund Olesen
createMachineVerifierPass and MachineFunction::verify. The banner is printed before the machine code dump, just like the printer pass. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122113 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-17Make the -verify-regalloc command line option available to base classes asJakob Stoklund Olesen
RegAllocBase::VerifyEnabled. Run the machine code verifier in a few interesting places during RegAllocGreedy. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122107 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-17Enable loop splitting in RegAllocGreedy.Jakob Stoklund Olesen
The heuristics split around the largest loop where the current register may be allocated without interference. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122106 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-15Start using SplitKit and MachineLoopRanges in RegAllocGreedy in preparation ofJakob Stoklund Olesen
live range splitting around loops guided by register pressure. So far, trySplit() simply prints a lot of debug output. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121918 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-14Simplify RegAllocGreedy's use of register aliases.Jakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121807 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-14Move debugging code entirely within DEBUG(). Silences an unused variableMatt Beaumont-Gay
warning in the opt build. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121791 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-14Add LiveIntervalUnion print methods, RegAllocGreedy::trySplit debug spew.Jakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121783 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-14Q.seenAllInterferences() must be called after Q.collectInterferingVRegs().Jakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121774 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-14Remove unused vector.Jakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121741 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-14Try reassigning all virtual register interferences, not just those with lowerJakob Stoklund Olesen
spill weight. Filter out fixed registers instead. Add support for reassigning an interference that was assigned to an alias. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121737 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-14Add stub for RAGreedy::trySplit.Jakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121736 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-11Add named timer groups for the different stages of register allocation.Jakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121604 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-10Move MRI into RegAllocBase. Clean up debug output a bit.Jakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121599 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-10Remove extraneous close parenthesis.Nick Lewycky
Fix build breakage. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121596 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-10Move variable that's unused in an NDEBUG build inside the DEBUG() macro, fixingNick Lewycky
lib/CodeGen/RegAllocGreedy.cpp:233: error: unused variable 'TRC' [-Wunused-variable] git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121594 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-10Force the greedy register allocator to always use the inline spiller.Jakob Stoklund Olesen
Soon, RegAllocGreedy will start splitting live ranges, and then deferred spilling won't work anyway. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121591 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-10Use AllocationOrder in RegAllocGreedy, fix a bug in the hint calculation.Jakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121584 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-10Fix miscompilation caused by trivial logic error in the reassignVReg()Jakob Stoklund Olesen
interference check. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121519 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-09Remember to filter out reserved rergisters from the allocation order.Jakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121411 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-09Added register reassignment prototype to RAGreedy. It's a simpleAndrew Trick
heuristic to reshuffle register assignments when we can't find an available reg. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121388 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-08Properly deal with empty intervals when checking for interference.Jakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121319 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-08Implement very primitive hinting support in RegAllocGreedy.Jakob Stoklund Olesen
The hint is simply tried first and then forgotten if it couldn't be allocated immediately. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121306 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-08Store (priority,regnum) pairs in the priority queue instead of providing anJakob Stoklund Olesen
abstract priority queue interface in subclasses that want to override the priority calculations. Subclasses must provide a getPriority() implementation instead. This approach requires less code as long as priorities are expressable as simple floats, and it avoids the dangers of defining potentially expensive priority comparison functions. It also should speed up priority_queue operations since they no longer have to chase pointers when comparing registers. This is not measurable, though. Preferably, we shouldn't use floats to guide code generation. The use of floats here is derived from the use of floats for spill weights. Spill weights have a dynamic range that doesn't lend itself easily to a fixpoint implementation. When someone invents a stable spill weight representation, it can be reused for allocation priorities. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121294 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-08Trim includes.Jakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121283 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-08Stub out RegAllocGreedy.Jakob Stoklund Olesen
This new register allocator is initially identical to RegAllocBasic, but it will receive all of the tricks that RegAllocBasic won't get. RegAllocGreedy will eventually replace linear scan. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121234 91177308-0d34-0410-b5e6-96231b3b80d8