Commit Graph

153 Commits

Author SHA1 Message Date
Benjamin Kramer
e7078aed24 Remove dead variable.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92919 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-07 17:29:08 +00:00
David Greene
1d44df6afe Change errs() to dbgs().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92532 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-04 23:02:10 +00:00
Jakob Stoklund Olesen
8f72235a77 Move PHIElimination::isLiveOut method to LiveVariables.
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
2009-12-01 17:13:31 +00:00
Evan Cheng
a4025df42d Fix PR5614: parts of a physical register def may be killed the rest.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90180 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-01 00:44:45 +00:00
Jakob Stoklund Olesen
323d8c3ed7 Be more clever about calculating live variables through new basic blocks.
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
2009-11-21 02:05:21 +00:00
Evan Cheng
236490d870 Fix PR5410: LiveVariables lost subreg def:
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
2009-11-13 20:36:40 +00:00
Jakob Stoklund Olesen
3e20475fee Fix liveness calculation when splitting critical edges during PHI elimination.
- 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
2009-11-11 19:31:31 +00:00
Jakob Stoklund Olesen
f235f13931 Teach PHIElimination to split critical edges when -split-phi-edges is enabled.
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
2009-11-10 22:01:05 +00:00
Evan Cheng
a2f8047134 When LiveVariables is adding implicit-def to model "partial dead", add the 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
2009-10-14 23:39:27 +00:00
Evan Cheng
ad934b821c Clean up LiveVariables and change how it deals with partial updates and 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
2009-09-24 02:15:22 +00:00
Evan Cheng
296925dc16 Fix PR5024. LiveVariables physical register defs should *commit* only after all
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
2009-09-23 06:28:31 +00:00
Evan Cheng
60c7df2c93 Fix PR5024. LiveVariables::FindLastPartialDef should return a set of 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
2009-09-22 08:34:46 +00:00
Chris Lattner
dbe89cd2f0 remove the last uses of Config/alloca.h
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79873 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-23 22:57:38 +00:00
Chris Lattner
705e07f578 remove various std::ostream version of printing methods from
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
2009-08-23 03:41:05 +00:00
Dan Gohman
ad2afc2a42 Reapply r77654 with a fix: MachineFunctionPass's getAnalysisUsage
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
2009-07-31 18:16:33 +00:00
Daniel Dunbar
c5b19b21d8 Revert r77654, it appears to be causing llvm-gcc bootstrap failures, and many
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
2009-07-31 03:02:41 +00:00
Dan Gohman
933c762371 Manage MachineFunctions with an analysis Pass instead of the Annotable
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
2009-07-31 01:52:50 +00:00
Evan Cheng
2c4d96dfe9 Avoid adding a duplicate def. This fixes PR4478.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74857 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-06 21:34:05 +00:00
Evan Cheng
694f6c81e8 Fix PR4419: handle defs of partial uses.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73816 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-20 04:34:51 +00:00
Evan Cheng
95299c194d If there is a def of a super-register followed by a use of a sub-register, 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
2009-06-03 05:15:46 +00:00
Jeffrey Yasskin
493a3d015c LiveVariables::VarInfo contains an AliveBlocks BitVector, which has as many
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
2009-05-26 18:27:15 +00:00
Evan Cheng
aed4a430f4 Eliminate VarInfo::UsedBlocks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72411 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-26 06:25:46 +00:00
Evan Cheng
a894ae130b Fix PR3243: a LiveVariables bug. When HandlePhysRegKill is checking whether 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
2009-01-20 21:25:12 +00:00
Devang Patel
59500c8f9a Silence unused variable warnings.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59841 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-21 20:00:59 +00:00
Dan Gohman
4a829ecc54 Use find_first/find_next to iterate through all the set bits in a
BitVector, instead of manually testing each bit.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59246 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-13 16:31:27 +00:00
Dan Gohman
d735b8019b Switch the MachineOperand accessors back to the short names like
isReg, etc., from isRegister, etc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57006 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-03 15:45:36 +00:00
Dan Gohman
3bdf5fe71a Factor out code into HandleVirtRegDef, for consistency with
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
2008-09-21 21:11:41 +00:00
Owen Anderson
bbf5583283 Use SmallSet instead of std::set to save allocations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54810 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-14 23:41:38 +00:00
Owen Anderson
bd3ba461eb - Fix SelectionDAG to generate correct CFGs.
- 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
2008-08-04 23:54:43 +00:00
Evan Cheng
9f1c8317a4 - Remove calls to copyKillDeadInfo which is an N^2 function. Instead, 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
2008-07-03 09:09:37 +00:00
Evan Cheng
5b9f60bc22 Use std::replace instead of std::find and push_back.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53063 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-03 00:28:27 +00:00
Evan Cheng
be04dc1413 - Add LiveVariables::replaceKillInstruction. This does a subset of 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
2008-07-03 00:07:19 +00:00
Owen Anderson
bffdf66b80 Use a SmallSet when we can to reduce memory allocations.
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
2008-06-27 07:05:59 +00:00
Dan Gohman
48b0b882c7 Fix the text in an assert string.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52744 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-25 22:14:43 +00:00
Bill Wendling
ebcba612b5 This situation can occur:
,------.
    |      |
    |      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
2008-06-23 23:41:14 +00:00
Evan Cheng
0d4bdde327 Rewrite LiveVariable liveness computation. The new implementation is much 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
2008-04-16 09:46:40 +00:00
Evan Cheng
ea1d9cdc4e Now that I am told MachineRegisterInfo also tracks physical register uses / 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
2008-04-02 18:04:08 +00:00
Evan Cheng
94202018c5 Fix live variables issues:
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
2008-03-19 00:52:20 +00:00
Evan Cheng
6130f66eaa Refactor code. Remove duplicated functions that basically do the same thing as
findRegisterUseOperandIdx, findRegisterDefOperandIndx. Fix some naming inconsistencies.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47927 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-05 00:59:57 +00:00
Bill Wendling
1d5e8196c0 Clear PhysRegPartUse for the sub register as well.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47453 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-21 19:35:27 +00:00
Bill Wendling
c927cc8731 Remove one of the fixmes that I put in there. From Evan:
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
2008-02-20 20:56:45 +00:00
Bill Wendling
55574c2cea Improve some comments explaining the "handle kills" stuff better.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47395 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-20 19:35:34 +00:00
Bill Wendling
fe8276cec2 Fix comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47389 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-20 19:09:14 +00:00
Bill Wendling
6d794746b7 Added some comments and reformatted others. No functionality change.
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
2008-02-20 09:15:16 +00:00
Bill Wendling
420cdebbcb More constification of things. More comments added. No functionality
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
2008-02-20 07:36:31 +00:00
Bill Wendling
90a3868fe5 No functionality change:
- 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
2008-02-20 06:10:21 +00:00
Dan Gohman
6f0d024a53 Rename MRegisterInfo to TargetRegisterInfo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46930 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-10 18:45:23 +00:00
Evan Cheng
bb4151bd1f If a vr is already marked alive in a bb, then it has PHI uses that are visited earlier, then it is not killed in the def block (i.e. not dead).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46763 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-05 20:04:18 +00:00
Owen Anderson
b487e7215c Move some functionality for adding flags to MachineInstr's into methods on MachineInstr rather than LiveVariables.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46295 91177308-0d34-0410-b5e6-96231b3b80d8
2008-01-24 01:10:07 +00:00
Owen Anderson
40a627ddf8 Move some calls to getVRegDef higher in the callgraph, so they don't get executed as frequently in performance sensitive code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46027 91177308-0d34-0410-b5e6-96231b3b80d8
2008-01-15 22:58:11 +00:00