Commit Graph

188 Commits

Author SHA1 Message Date
Chad Rosier c7505ef8ba Simplify logic now that r182490 is in place. No functional change intended.
llvm-svn: 182526
2013-05-22 22:26:05 +00:00
Jakob Stoklund Olesen c338679c9d Remove special-casing of return blocks for liveness.
Now that return value registers are return instruction uses, there is no
need for special treatment of return blocks.

llvm-svn: 174416
2013-02-05 18:21:52 +00:00
Chandler Carruth ed0881b2a6 Use the new script to sort the includes of every file under lib.
Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.

Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]

llvm-svn: 169131
2012-12-03 16:50:05 +00:00
Jakob Stoklund Olesen c30a9af2d7 Switch most getReservedRegs() clients to the MRI equivalent.
Using the cached bit vector in MRI avoids comstantly allocating and
recomputing the reserved register bit vector.

llvm-svn: 165983
2012-10-15 21:57:41 +00:00
Manman Ren 19f49ac624 Release build: guard dump functions with
"#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)"

No functional change. Update r163339.

llvm-svn: 163653
2012-09-11 22:23:19 +00:00
Benjamin Kramer 851c941b8b LiveVariables: Compute a set of defs and kills to speed up updating LV during critical edge splitting.
Previously we checked if the register is def'd in a block via the def/use list a
nd walked the list of kills to check if the register is killed in a block. Both
of these checks can be made much cheaper by walking the block first and
recording all defs and kills.

This reduces the compile time of the test case from PR13651 from 40s to 15s at
-O2. The compile time is still dominated by LV updating but now the main culprit
is SparseBitVector's slowness.

llvm-svn: 163478
2012-09-09 11:56:14 +00:00
Manman Ren 742534c4dc Release build: guard dump functions with "ifndef NDEBUG"
No functional change.

llvm-svn: 163339
2012-09-06 19:06:06 +00:00
Jakob Stoklund Olesen 502e4c6ac4 Teach LiveVariables to handle <undef> operands.
It's simple: Don't treat <undef> operands as uses, and don't assume a
virtual register has a defining instruction unless a real use has been
seen.

llvm-svn: 159061
2012-06-23 02:23:00 +00:00
Jakob Stoklund Olesen 54038d796c Switch all register list clients to the new MC*Iterator interface.
No functional change intended.

Sorry for the churn. The iterator classes are supposed to help avoid
giant commits like this one in the future. The TableGen-produced
register lists are getting quite large, and it may be necessary to
change the table representation.

This makes it possible to do so without changing all clients (again).

llvm-svn: 157854
2012-06-01 23:28:30 +00:00
Lang Hames 652f21274f Fix typo.
llvm-svn: 153846
2012-04-01 19:27:25 +00:00
Jakob Stoklund Olesen 7d544f9165 Assert on SSA errors in LiveVariables.
All uses of a virtual register must be dominated by its def.

llvm-svn: 152449
2012-03-09 23:41:44 +00:00
Craig Topper 4b02a29eba Convert more GenRegisterInfo tables from unsigned to uint16_t to reduce static data size.
llvm-svn: 152016
2012-03-05 05:37:41 +00:00
Andrew Trick d3f8fe81f4 RegAlloc superpass: includes phi elimination, coalescing, and scheduling.
Creates a configurable regalloc pipeline.

Ensure specific llc options do what they say and nothing more: -reglloc=... has no effect other than selecting the allocator pass itself. This patch introduces a new umbrella flag, "-optimize-regalloc", to enable/disable the optimizing regalloc "superpass". This allows for example testing coalscing and scheduling under -O0 or vice-versa.

When a CodeGen pass requires the MachineFunction to have a particular property, we need to explicitly define that property so it can be directly queried rather than naming a specific Pass. For example, to check for SSA, use MRI->isSSA, not addRequired<PHIElimination>.

CodeGen transformation passes are never "required" as an analysis

ProcessImplicitDefs does not require LiveVariables.

We have a plan to massively simplify some of the early passes within the regalloc superpass.

llvm-svn: 150226
2012-02-10 04:10:36 +00:00
Andrew Trick 808a7a6ce6 whitespace
llvm-svn: 149671
2012-02-03 05:12:30 +00:00
Evan Cheng 64a2beca52 Fix an obvious typo.
llvm-svn: 148622
2012-01-21 03:31:03 +00:00
Jakob Stoklund Olesen 8e3bb315d8 Handle register masks in LiveVariables.
A register mask operand kills any live physreg that isn't preserved.
Unlike an implicit-def operand, the clobbered physregs are never live
afterwards.

This means LiveVariables has to track a much smaller number of live
physregs, and it should spend much less time in addRegisterDead().

llvm-svn: 148609
2012-01-21 00:58:53 +00:00
Jakob Stoklund Olesen 52ee45d64a Delete an unused member variable.
llvm-svn: 148594
2012-01-20 22:48:59 +00:00
Evan Cheng 6bb95253eb After r147827 and r147902, it's now possible for unallocatable registers to be
live across BBs before register allocation. This miscompiled 197.parser
when a cmp + b are optimized to a cbnz instruction even though the CPSR def
is live-in a successor.
        cbnz    r6, LBB89_12
...
LBB89_12:
        ble     LBB89_1

The fix consists of two parts. 1) Teach LiveVariables that some unallocatable
registers might be liveouts so don't mark their last use as kill if they are.
2) ARM constantpool island pass shouldn't form cbz / cbnz if the conditional
branch does not kill CPSR.

rdar://10676853

llvm-svn: 148168
2012-01-14 01:53:46 +00:00
Evan Cheng 7f8e563a69 Add bundle aware API for querying instruction properties and switch the code
generator to it. For non-bundle instructions, these behave exactly the same
as the MC layer API.

For properties like mayLoad / mayStore, look into the bundle and if any of the
bundled instructions has the property it would return true.
For properties like isPredicable, only return true if *all* of the bundled
instructions have the property.
For properties like canFoldAsLoad, isCompare, conservatively return false for
bundles.

llvm-svn: 146026
2011-12-07 07:15:52 +00:00
Evan Cheng 2a81dd4a3c First chunk of MachineInstr bundle support.
1. Added opcode BUNDLE
2. Taught MachineInstr class to deal with bundled MIs
3. Changed MachineBasicBlock iterator to skip over bundled MIs; added an iterator to walk all the MIs
4. Taught MachineBasicBlock methods about bundled MIs

llvm-svn: 145975
2011-12-06 22:12:01 +00:00
Duncan Sands a41634e307 Silence a bunch (but not all) "variable written but not read" warnings
when building with assertions disabled.

llvm-svn: 137460
2011-08-12 14:54:45 +00:00
Benjamin Kramer b8ca01fff5 Reduce vector reallocations.
llvm-svn: 127254
2011-03-08 17:28:36 +00:00
Jakob Stoklund Olesen 28d76692b6 Use an IndexedMap for LiveVariables::VirtRegInfo.
Provide MRI::getNumVirtRegs() and TRI::index2VirtReg() functions to allow
iteration over virtual registers without depending on the representation of
virtual register numbers.

llvm-svn: 123098
2011-01-08 23:10:57 +00:00
Owen Anderson 8ac477ffb5 Begin adding static dependence information to passes, which will allow us to
perform initialization without static constructors AND without explicit initialization
by the client.  For the moment, passes are required to initialize both their
(potential) dependencies and any passes they preserve.  I hope to be able to relax
the latter requirement in the future.

llvm-svn: 116334
2010-10-12 19:48:12 +00:00
Owen Anderson df7a4f2515 Now with fewer extraneous semicolons!
llvm-svn: 115996
2010-10-07 22:25:06 +00:00
Jakob Stoklund Olesen 5f72a04ba7 Remove unused functions.
llvm-svn: 111156
2010-08-16 17:18:20 +00:00
Owen Anderson a57b97e7e7 Fix batch of converting RegisterPass<> to INTIALIZE_PASS().
llvm-svn: 109045
2010-07-21 22:09:45 +00:00
Chris Lattner 0fc88efda3 fix a -Wbool-conversions warning from clang.
llvm-svn: 105942
2010-06-14 18:28:34 +00:00
Dale Johannesen df1a7f83bf Fix some liveout handling related to tail calls, see comments.
I don't think this ever resulted in problems on x86, but it
would on ARM.

llvm-svn: 105509
2010-06-05 00:30:45 +00:00
Dan Gohman 9d2d053e11 Eliminate MachineBasicBlock::const_livein_iterator and make
MachineBasicBlock::livein_iterator a const_iterator, because
clients shouldn't ever be using the iterator interface to
mutate the livein set.

llvm-svn: 101147
2010-04-13 16:57:55 +00:00
Evan Cheng eb50ac5ccc LiveVariables should clear kill / dead markers first. This allows us to remove a hack in the scheduler.
llvm-svn: 99597
2010-03-26 02:12:24 +00:00
Jakob Stoklund Olesen 2664d295cb Better handling of dead super registers in LiveVariables. We used to do this:
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
2010-03-05 21:49:17 +00:00
Jakob Stoklund Olesen 38b76e27a7 Keep track of phi join registers explicitly in LiveVariables.
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
2010-02-23 22:43:58 +00:00
Chris Lattner b06015aa69 move target-independent opcodes out of TargetInstrInfo
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
2010-02-09 19:54:29 +00:00
Dale Johannesen c3adf44885 Skip DEBUG_VALUE in some places where it was affecting codegen.
llvm-svn: 95647
2010-02-09 02:01:46 +00:00
Benjamin Kramer d64b952e5e Remove dead variable.
llvm-svn: 92919
2010-01-07 17:29:08 +00:00
David Greene d599dcd754 Change errs() to dbgs().
llvm-svn: 92532
2010-01-04 23:02:10 +00:00
Jakob Stoklund Olesen defc47088a 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.

llvm-svn: 90240
2009-12-01 17:13:31 +00:00
Evan Cheng 1d31fc9123 Fix PR5614: parts of a physical register def may be killed the rest.
llvm-svn: 90180
2009-12-01 00:44:45 +00:00
Jakob Stoklund Olesen bc630aca39 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.

llvm-svn: 89530
2009-11-21 02:05:21 +00:00
Evan Cheng d190b8216f 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.

llvm-svn: 88690
2009-11-13 20:36:40 +00:00
Jakob Stoklund Olesen 4f7fd3baeb 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.

llvm-svn: 86867
2009-11-11 19:31:31 +00:00
Jakob Stoklund Olesen 4453dc976b 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.

llvm-svn: 86725
2009-11-10 22:01:05 +00:00
Evan Cheng 2f61e0946a When LiveVariables is adding implicit-def to model "partial dead", add the earlyclobber marker if the superreg def has it.
llvm-svn: 84153
2009-10-14 23:39:27 +00:00
Evan Cheng a21aac3811 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.
llvm-svn: 82676
2009-09-24 02:15:22 +00:00
Evan Cheng 262f86ed90 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.

llvm-svn: 82616
2009-09-23 06:28:31 +00:00
Evan Cheng 08d1e41c10 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.
llvm-svn: 82535
2009-09-22 08:34:46 +00:00
Chris Lattner 30ebdc4311 remove the last uses of Config/alloca.h
llvm-svn: 79873
2009-08-23 22:57:38 +00:00
Chris Lattner a6f074fb3a 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. ;-)

llvm-svn: 79813
2009-08-23 03:41:05 +00:00
Dan Gohman 5ea74d55ce 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.

llvm-svn: 77691
2009-07-31 18:16:33 +00:00