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2010-03-05Better handling of dead super registers in LiveVariables. We used to do this:Jakob Stoklund Olesen
CALL ... %RAX<imp-def> ... [not using %RAX] %EAX = ..., %RAX<imp-use, kill> RET %EAX<imp-use,kill> Now we do this: CALL ... %RAX<imp-def, dead> ... [not using %RAX] %EAX = ... RET %EAX<imp-use,kill> By not artificially keeping %RAX alive, we lower register pressure a bit. The correct number of instructions for 2008-08-05-SpillerBug.ll is obviously 55, anybody can see that. Sheesh. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97838 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-23Keep track of phi join registers explicitly in LiveVariables.Jakob Stoklund Olesen
Previously, LiveIntervalAnalysis would infer phi joins by looking for multiply defined registers. That doesn't work if the phi join is implicitly defined in all but one of the predecessors. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96994 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-09move target-independent opcodes out of TargetInstrInfoChris Lattner
into TargetOpcodes.h. #include the new TargetOpcodes.h into MachineInstr. Add new inline accessors (like isPHI()) to MachineInstr, and start using them throughout the codebase. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95687 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-09Skip DEBUG_VALUE in some places where it was affecting codegen.Dale Johannesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95647 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-07Remove dead variable.Benjamin Kramer
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92919 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-04Change errs() to dbgs().David Greene
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92532 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-01Move PHIElimination::isLiveOut method to LiveVariables.Jakob Stoklund Olesen
We want LiveVariables clients to use methods rather than accessing the getVarInfo data structure directly. That way it will be possible to change the LiveVariables representation. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90240 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-01Fix PR5614: parts of a physical register def may be killed the rest.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90180 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-21Be more clever about calculating live variables through new basic blocks.Jakob Stoklund Olesen
When splitting a critical edge, the registers live through the edge are: - Used in a PHI instruction, or - Live out from the predecessor, and - Live in to the successor. This allows the coalescer to eliminate even more phi joins. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89530 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-13Fix PR5410: LiveVariables lost subreg def:Evan Cheng
D0<def,dead> = ... ... = S0<use, kill> S0<def> = ... ... D0<def> = The first D0 def is correctly marked dead, however, livevariables should have added an implicit def of S0 or we end up with a use without a def. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@88690 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-11Fix liveness calculation when splitting critical edges during PHI elimination.Jakob Stoklund Olesen
- Edges are split before any phis are eliminated, so the code is SSA. - Create a proper IR BasicBlock for the split edges. - LiveVariables::addNewBlock now has same syntax as MachineDominatorTree::addNewBlock. Algorithm calculates predecessor live-out set rather than successor live-in set. This feature still causes some miscompilations. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86867 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-10Teach PHIElimination to split critical edges when -split-phi-edges is enabled.Jakob Stoklund Olesen
Critical edges leading to a PHI node are split when the PHI source variable is live out from the predecessor block. This help the coalescer eliminate more PHI joins. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86725 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-14When LiveVariables is adding implicit-def to model "partial dead", add the ↵Evan Cheng
earlyclobber marker if the superreg def has it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84153 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-24Clean up LiveVariables and change how it deals with partial updates and ↵Evan Cheng
kills. This also eliminate the horrible check which scan forward to the end of the basic block. It should be faster and more accurate. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82676 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-23Fix PR5024. LiveVariables physical register defs should *commit* only after allEvan Cheng
of the defs are processed. Also fix a implicit_def propagation bug: a implicit_def of a physical register should be applied to uses of the sub-registers. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82616 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-22Fix PR5024. LiveVariables::FindLastPartialDef should return a set of ↵Evan Cheng
sub-registers that were defined by the last partial def, not just a single sub-register. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82535 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-23remove the last uses of Config/alloca.hChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79873 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-23remove various std::ostream version of printing methods fromChris Lattner
MachineInstr and MachineOperand. This required eliminating a bunch of stuff that was using DOUT, I hope that bill doesn't mind me stealing his fun. ;-) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79813 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-31Reapply r77654 with a fix: MachineFunctionPass's getAnalysisUsageDan Gohman
shouldn't do AU.setPreservesCFG(), because even though CodeGen passes don't modify the LLVM IR CFG, they may modify the MachineFunction CFG, and passes like MachineLoop are registered with isCFGOnly set to true. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77691 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-31Revert r77654, it appears to be causing llvm-gcc bootstrap failures, and manyDaniel Dunbar
failures when building assorted projects with clang. --- Reverse-merging r77654 into '.': U include/llvm/CodeGen/Passes.h U include/llvm/CodeGen/MachineFunctionPass.h U include/llvm/CodeGen/MachineFunction.h U include/llvm/CodeGen/LazyLiveness.h U include/llvm/CodeGen/SelectionDAGISel.h D include/llvm/CodeGen/MachineFunctionAnalysis.h U include/llvm/Function.h U lib/Target/CellSPU/SPUISelDAGToDAG.cpp U lib/Target/PowerPC/PPCISelDAGToDAG.cpp U lib/CodeGen/LLVMTargetMachine.cpp U lib/CodeGen/MachineVerifier.cpp U lib/CodeGen/MachineFunction.cpp U lib/CodeGen/PrologEpilogInserter.cpp U lib/CodeGen/MachineLoopInfo.cpp U lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp D lib/CodeGen/MachineFunctionAnalysis.cpp D lib/CodeGen/MachineFunctionPass.cpp U lib/CodeGen/LiveVariables.cpp git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77661 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-31Manage MachineFunctions with an analysis Pass instead of the AnnotableDan Gohman
mechanism. To support this, make MachineFunctionPass a little more complete. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77654 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-06Avoid adding a duplicate def. This fixes PR4478.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74857 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-20Fix PR4419: handle defs of partial uses.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73816 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-03If there is a def of a super-register followed by a use of a sub-register, ↵Evan Cheng
do *not* add an implicit def of the sub-register. e.g. EAX = ..., AX<imp-def> ... = AX This creates a double-def. Apparently this used to be necessary but is no longer needed. Thanks to Anton for pointing this out. Anton, I cannot create a test case without your uncommitted ARM patches. Please check in a test case for me. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72755 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-26LiveVariables::VarInfo contains an AliveBlocks BitVector, which has as manyJeffrey Yasskin
entries as there are basic blocks in the function. LiveVariables::getVarInfo creates a VarInfo struct for every register in the function, leading to quadratic space use. This patch changes the BitVector to a SparseBitVector, which doesn't help the worst-case memory use but does reduce the actual use in very long functions with short-lived variables. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72426 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-26Eliminate VarInfo::UsedBlocks.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72411 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-20Fix PR3243: a LiveVariables bug. When HandlePhysRegKill is checking whether ↵Evan Cheng
the last reference is also the last def (i.e. dead def), it should also check if last reference is the current machine instruction being processed. This can happen when it is processing a physical register use and setting the current machine instruction as sub-register's last ref. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62617 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-21Silence unused variable warnings.Devang Patel
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59841 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-13Use find_first/find_next to iterate through all the set bits in aDan Gohman
BitVector, instead of manually testing each bit. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59246 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-03Switch the MachineOperand accessors back to the short names likeDan Gohman
isReg, etc., from isRegister, etc. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57006 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-21Factor out code into HandleVirtRegDef, for consistency withDan Gohman
Handle{Virt,Phys}Reg{Def,Use}. Remove a redundant check for register zero, and redundant checks for isPhysicalRegister. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56412 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-14Use SmallSet instead of std::set to save allocations.Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54810 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-04- Fix SelectionDAG to generate correct CFGs.Owen Anderson
- Add a basic machine-level dead block eliminator. These two have to go together, since many other parts of the code generator are unable to handle the unreachable blocks otherwise created. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54333 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-03- Remove calls to copyKillDeadInfo which is an N^2 function. Instead, ↵Evan Cheng
propagate kill / dead markers as new instructions are constructed in foldMemoryOperand, convertToThressAddress, etc. - Also remove LiveVariables::instructionChanged, etc. Replace all calls with cheaper calls which update VarInfo kill list. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53097 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-03Use std::replace instead of std::find and push_back.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53063 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-03- Add LiveVariables::replaceKillInstruction. This does a subset of ↵Evan Cheng
instructionChanged. That is, it only update the VarInfo.kills if the new instruction is known to have the correct dead and kill markers. - CommuteInstruction copies kill / dead markers over to new instruction. So use replaceKillInstruction instead. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53061 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-27Use a SmallSet when we can to reduce memory allocations.Owen Anderson
This speeds up a particular testcase from 0.0302s to 0.0222s in LiveVariables. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52819 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-25Fix the text in an assert string.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52744 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-23This situation can occur:Bill Wendling
,------. | | | v | t2 = phi ... t1 ... | | | v | t1 = ... | ... = ... t1 ... | | `------' where there is a use in a PHI node that's a predecessor to the defining block. We don't want to mark all predecessors as having the value "alive" in this case. Also, the assert was too restrictive and didn't handle this case. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52655 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-16Rewrite LiveVariable liveness computation. The new implementation is much ↵Evan Cheng
simplified. It eliminated the nasty recursive routines and removed the partial def / use bookkeeping. There is also potential for performance improvement by replacing the conservative handling of partial physical register definitions. The code is currently disabled until live interval analysis is taught of the name scheme. This patch also fixed a couple of nasty corner cases. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49784 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-02Now that I am told MachineRegisterInfo also tracks physical register uses / ↵Evan Cheng
defs, I can do away with the horribleness I introduced a while back. It's impossible to detect if there is any use of a physical register below an instruction (and before any def of the register) with some cheap book keeping. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49105 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-19Fix live variables issues:Evan Cheng
1. If part of a register is re-defined, an implicit kill and an implicit def are added to denote read / mod / write. However, this should only be necessary if the register is actually read later. This is a performance issue. 2. If a sub-register is being defined, and it doesn't have a previous use, do not add a implicit kill to the last use of a super-register: = EAX, AX<imp-use,kill> ... AX = In this case, EAX is live but AX is killed, this is wrong and will cause the coalescer to do bad things. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48521 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-05Refactor code. Remove duplicated functions that basically do the same thing asEvan Cheng
findRegisterUseOperandIdx, findRegisterDefOperandIndx. Fix some naming inconsistencies. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47927 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-21Clear PhysRegPartUse for the sub register as well.Bill Wendling
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47453 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-20Remove one of the fixmes that I put in there. From Evan:Bill Wendling
No need to go up more levels. A def of a register also sets its sub-registers (so if PhysRegInfo[SuperReg] is NULL, it means SuperReg's super registers are not previously defined). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47399 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-20Improve some comments explaining the "handle kills" stuff better.Bill Wendling
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47395 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-20Fix comment.Bill Wendling
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47389 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-20Added some comments and reformatted others. No functionality change.Bill Wendling
Added two "FIXMEs" for code that looks dubious to me (but I could be wrong). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47366 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-20More constification of things. More comments added. No functionalityBill Wendling
changes. (Sorry for any formatting changes that creeped in.) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47362 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-20No functionality change:Bill Wendling
- Constified some MachineOperand values. - Added/Modified some comments. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47358 91177308-0d34-0410-b5e6-96231b3b80d8
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