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* Better handling of dead super registers in LiveVariables. We used to do this:Jakob Stoklund Olesen2010-03-051-21/+21
| | | | | | | | | | | | | | | | | | | | | 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. llvm-svn: 97838
* Keep track of phi join registers explicitly in LiveVariables.Jakob Stoklund Olesen2010-02-231-0/+1
| | | | | | | | 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. llvm-svn: 96994
* move target-independent opcodes out of TargetInstrInfoChris Lattner2010-02-091-5/+4
| | | | | | | | | 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. llvm-svn: 95687
* Skip DEBUG_VALUE in some places where it was affecting codegen.Dale Johannesen2010-02-091-0/+2
| | | | llvm-svn: 95647
* Remove dead variable.Benjamin Kramer2010-01-071-7/+2
| | | | llvm-svn: 92919
* Change errs() to dbgs().David Greene2010-01-041-6/+7
| | | | llvm-svn: 92532
* Move PHIElimination::isLiveOut method to LiveVariables.Jakob Stoklund Olesen2009-12-011-0/+45
| | | | | | | | 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. llvm-svn: 90240
* Fix PR5614: parts of a physical register def may be killed the rest.Evan Cheng2009-12-011-1/+47
| | | | llvm-svn: 90180
* Be more clever about calculating live variables through new basic blocks.Jakob Stoklund Olesen2009-11-211-19/+29
| | | | | | | | | | | | 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. llvm-svn: 89530
* Fix PR5410: LiveVariables lost subreg def:Evan Cheng2009-11-131-1/+7
| | | | | | | | | | | | | | 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. llvm-svn: 88690
* Fix liveness calculation when splitting critical edges during PHI elimination.Jakob Stoklund Olesen2009-11-111-20/+21
| | | | | | | | | | | | | | - 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. llvm-svn: 86867
* Teach PHIElimination to split critical edges when -split-phi-edges is enabled.Jakob Stoklund Olesen2009-11-101-0/+40
| | | | | | | | 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. llvm-svn: 86725
* When LiveVariables is adding implicit-def to model "partial dead", add the ↵Evan Cheng2009-10-141-1/+12
| | | | | | earlyclobber marker if the superreg def has it. llvm-svn: 84153
* Clean up LiveVariables and change how it deals with partial updates and ↵Evan Cheng2009-09-241-198/+64
| | | | | | kills. This also eliminate the horrible check which scan forward to the end of the basic block. It should be faster and more accurate. llvm-svn: 82676
* Fix PR5024. LiveVariables physical register defs should *commit* only after allEvan Cheng2009-09-231-32/+93
| | | | | | | | 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. llvm-svn: 82616
* Fix PR5024. LiveVariables::FindLastPartialDef should return a set of ↵Evan Cheng2009-09-221-6/+22
| | | | | | sub-registers that were defined by the last partial def, not just a single sub-register. llvm-svn: 82535
* remove the last uses of Config/alloca.hChris Lattner2009-08-231-1/+0
| | | | llvm-svn: 79873
* remove various std::ostream version of printing methods fromChris Lattner2009-08-231-6/+6
| | | | | | | | 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. ;-) llvm-svn: 79813
* Reapply r77654 with a fix: MachineFunctionPass's getAnalysisUsageDan Gohman2009-07-311-0/+1
| | | | | | | | 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. llvm-svn: 77691
* Revert r77654, it appears to be causing llvm-gcc bootstrap failures, and manyDaniel Dunbar2009-07-311-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | 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 llvm-svn: 77661
* Manage MachineFunctions with an analysis Pass instead of the AnnotableDan Gohman2009-07-311-0/+1
| | | | | | | mechanism. To support this, make MachineFunctionPass a little more complete. llvm-svn: 77654
* Avoid adding a duplicate def. This fixes PR4478.Evan Cheng2009-07-061-2/+11
| | | | llvm-svn: 74857
* Fix PR4419: handle defs of partial uses.Evan Cheng2009-06-201-7/+6
| | | | llvm-svn: 73816
* If there is a def of a super-register followed by a use of a sub-register, ↵Evan Cheng2009-06-031-14/+0
| | | | | | | | | | | | | | 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. llvm-svn: 72755
* LiveVariables::VarInfo contains an AliveBlocks BitVector, which has as manyJeffrey Yasskin2009-05-261-9/+8
| | | | | | | | | | 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. llvm-svn: 72426
* Eliminate VarInfo::UsedBlocks.Evan Cheng2009-05-261-5/+0
| | | | llvm-svn: 72411
* Fix PR3243: a LiveVariables bug. When HandlePhysRegKill is checking whether ↵Evan Cheng2009-01-201-13/+15
| | | | | | 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. llvm-svn: 62617
* Silence unused variable warnings.Devang Patel2008-11-211-0/+1
| | | | llvm-svn: 59841
* Use find_first/find_next to iterate through all the set bits in aDan Gohman2008-11-131-4/+4
| | | | | | BitVector, instead of manually testing each bit. llvm-svn: 59246
* Switch the MachineOperand accessors back to the short names likeDan Gohman2008-10-031-2/+2
| | | | | | isReg, etc., from isRegister, etc. llvm-svn: 57006
* Factor out code into HandleVirtRegDef, for consistency withDan Gohman2008-09-211-13/+12
| | | | | | | Handle{Virt,Phys}Reg{Def,Use}. Remove a redundant check for register zero, and redundant checks for isPhysicalRegister. llvm-svn: 56412
* Use SmallSet instead of std::set to save allocations.Owen Anderson2008-08-141-3/+3
| | | | llvm-svn: 54810
* - Fix SelectionDAG to generate correct CFGs.Owen Anderson2008-08-041-0/+7
| | | | | | | | - 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. llvm-svn: 54333
* - Remove calls to copyKillDeadInfo which is an N^2 function. Instead, ↵Evan Cheng2008-07-031-47/+0
| | | | | | | | 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. llvm-svn: 53097
* Use std::replace instead of std::find and push_back.Evan Cheng2008-07-031-2/+1
| | | | llvm-svn: 53063
* - Add LiveVariables::replaceKillInstruction. This does a subset of ↵Evan Cheng2008-07-031-0/+9
| | | | | | | | 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. llvm-svn: 53061
* Use a SmallSet when we can to reduce memory allocations.Owen Anderson2008-06-271-1/+2
| | | | | | This speeds up a particular testcase from 0.0302s to 0.0222s in LiveVariables. llvm-svn: 52819
* Fix the text in an assert string.Dan Gohman2008-06-251-1/+1
| | | | llvm-svn: 52744
* This situation can occur:Bill Wendling2008-06-231-2/+17
| | | | | | | | | | | | | | | | | | | ,------. | | | 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. llvm-svn: 52655
* Rewrite LiveVariable liveness computation. The new implementation is much ↵Evan Cheng2008-04-161-219/+239
| | | | | | | | 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. llvm-svn: 49784
* Now that I am told MachineRegisterInfo also tracks physical register uses / ↵Evan Cheng2008-04-021-24/+64
| | | | | | 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. llvm-svn: 49105
* Fix live variables issues:Evan Cheng2008-03-191-6/+43
| | | | | | | | | | | 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. llvm-svn: 48521
* Refactor code. Remove duplicated functions that basically do the same thing asEvan Cheng2008-03-051-70/+24
| | | | | | findRegisterUseOperandIdx, findRegisterDefOperandIndx. Fix some naming inconsistencies. llvm-svn: 47927
* Clear PhysRegPartUse for the sub register as well.Bill Wendling2008-02-211-1/+1
| | | | llvm-svn: 47453
* Remove one of the fixmes that I put in there. From Evan:Bill Wendling2008-02-201-2/+3
| | | | | | | | 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). llvm-svn: 47399
* Improve some comments explaining the "handle kills" stuff better.Bill Wendling2008-02-201-2/+4
| | | | llvm-svn: 47395
* Fix comment.Bill Wendling2008-02-201-2/+1
| | | | llvm-svn: 47389
* Added some comments and reformatted others. No functionality change.Bill Wendling2008-02-201-28/+43
| | | | | | | Added two "FIXMEs" for code that looks dubious to me (but I could be wrong). llvm-svn: 47366
* More constification of things. More comments added. No functionalityBill Wendling2008-02-201-44/+76
| | | | | | changes. (Sorry for any formatting changes that creeped in.) llvm-svn: 47362
* No functionality change:Bill Wendling2008-02-201-31/+42
| | | | | | | - Constified some MachineOperand values. - Added/Modified some comments. llvm-svn: 47358
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