Commit Graph

244 Commits

Author SHA1 Message Date
Jakob Stoklund Olesen
200a8cef25 Also add <imp-use,kill> flags for redefined super-registers.
For example:

  %vreg10:dsub_0<def,undef> = COPY %vreg1
  %vreg10:dsub_1<def> = COPY %vreg2

is rewritten as:

  %D2<def> = COPY %D0, %Q1<imp-def>
  %D3<def> = COPY %D1, %Q1<imp-use,kill>, %Q1<imp-def>

The first COPY doesn't care about the previous value of %Q1, so it
doesn't read that register.

The second COPY is a partial redefinition of %Q1, so it implicitly kills
and redefines that register.

This makes it possible to recognize instructions that can harmlessly
clobber the full super-register.  The write and don't read the
super-register.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141139 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-05 00:01:48 +00:00
Jakob Stoklund Olesen
01afdb3a45 VirtRegMap is counting spill slots, not register spills.
Fix the stats counters to reflect that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139819 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-15 18:31:13 +00:00
Jakob Stoklund Olesen
cf5e5f3cc0 Also count identity copies.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130996 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-06 17:59:57 +00:00
Jakob Stoklund Olesen
93e110ba34 Also add <imp-def> operands for defined and dead super-registers when rewriting.
We cannot rely on the <imp-def> operands added by LiveIntervals in all cases as
demonstrated by the test case.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130313 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-27 17:42:31 +00:00
Jakob Stoklund Olesen
280ea1a746 Don't completely eliminate identity copies that also modify super register liveness.
Turn them into noop KILL instructions instead. This lets the scavenger know when
super-registers are killed and defined.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128645 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-31 17:55:25 +00:00
Jakob Stoklund Olesen
bf824efcb9 Dump the register map before rewriting.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128143 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-23 04:32:49 +00:00
Jakob Stoklund Olesen
ba05c01dab Add VirtRegMap::rewrite() and use it in the new register allocators.
The rewriter works almost identically to -rewriter=trivial, except it also
eliminates any identity copies.

This makes the new register allocators independent of VirtRegRewriter.cpp which
will be going away at the same time as RegAllocLinearScan.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125967 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-18 22:03:18 +00:00
Jakob Stoklund Olesen
c9df025e33 Simplify a bunch of isVirtualRegister() and isPhysicalRegister() logic.
These functions not longer assert when passed 0, but simply return false instead.

No functional change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123155 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-10 02:58:51 +00:00
Jakob Stoklund Olesen
42e9c96392 Remove MachineRegisterInfo::getLastVirtReg(), it was giving wrong results
when no virtual registers have been allocated.

It was only used to resize IndexedMaps, so provide an IndexedMap::resize()
method such that

 Map.grow(MRI.getLastVirtReg());

can be replaced with the simpler

 Map.resize(MRI.getNumVirtRegs());

This works correctly when no virtuals are allocated, and it bypasses the to/from
index conversions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123130 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 21:58:20 +00:00
Jakob Stoklund Olesen
4314268128 Replace TargetRegisterInfo::printReg with a PrintReg class that also works without a TRI instance.
Print virtual registers numbered from 0 instead of the arbitrary
FirstVirtualRegister. The first virtual register is printed as %vreg0.
TRI::NoRegister is printed as %noreg.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123107 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 03:05:53 +00:00
Jakob Stoklund Olesen
c7d67f90d3 Fix VirtRegMap to use TRI::index2VirtReg and TRI::virtReg2Index instead of
depending on TRI::FirstVirtualRegister.

Also use TRI::printReg instead of printing virtual registers directly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123101 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 23:11:07 +00:00
Jakob Stoklund Olesen
b55e91e087 Remember to resize SpillSlotToUsesMap when allocating an emergency spill slot.
Use amazing new function call technology instead of writing identical code in
multiple places.

This fixes PR8604.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119306 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-16 00:41:01 +00:00
Owen Anderson
ce665bd2e2 Now with fewer extraneous semicolons!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115996 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-07 22:25:06 +00:00
Owen Anderson
d13db2c59c Fix batch of converting RegisterPass<> to INTIALIZE_PASS().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109045 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-21 22:09:45 +00:00
Jakob Stoklund Olesen
243296690e Use the right floating point load/store instructions in PPCInstrInfo::foldMemoryOperandImpl().
The PowerPC floating point registers can represent both f32 and f64 via the
two register classes F4RC and F8RC. F8RC is considered a subclass of F4RC to
allow cross-class coalescing. This coalescing only affects whether registers
are spilled as f32 or f64.

Spill slots must be accessed with load/store instructions corresponding to the
class of the spilled register. PPCInstrInfo::foldMemoryOperandImpl was looking
at the instruction opcode which is wrong.

X86 has similar floating point register classes, but doesn't try to fold
memory operands, so there is no problem there.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97262 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-26 21:09:24 +00:00
Dan Gohman
f451cb870e Fix "the the" and similar typos.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95781 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-10 16:03:48 +00:00
David Greene
0080b1accc Change errs() to dbgs().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92587 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 01:25:45 +00:00
David Greene
3f2bf85d14 Add a bool flag to StackObjects telling whether they reference spill
slots.  The AsmPrinter will use this information to determine whether to
print a spill/reload comment.

Remove default argument values.  It's too easy to pass a wrong argument
value when multiple arguments have default values.  Make everything
explicit to trap bugs early.

Update all targets to adhere to the new interfaces..


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@87022 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-12 20:49:22 +00:00
Lang Hames
233a60ec40 The Indexes Patch.
This introduces a new pass, SlotIndexes, which is responsible for numbering
instructions for register allocation (and other clients). SlotIndexes numbering
is designed to match the existing scheme, so this patch should not cause any
changes in the generated code.

For consistency, and to avoid naming confusion, LiveIndex has been renamed
SlotIndex.

The processImplicitDefs method of the LiveIntervals analysis has been moved
into its own pass so that it can be run prior to SlotIndexes. This was
necessary to match the existing numbering scheme.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85979 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-03 23:52:08 +00:00
Evan Cheng
491f54f1fd Distinquish stack slots from other stack objects. They (and fixed objects) get FixedStack PseudoSourceValues.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84326 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-17 09:20:14 +00:00
Chris Lattner
d9ea85ab01 remove some uses of llvm/Support/Streams.h
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79842 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-23 08:43:55 +00:00
Daniel Dunbar
1cd1d98232 Move more to raw_ostream, provide support for writing MachineBasicBlock,
LiveInterval, etc to raw_ostream.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76965 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-24 10:36:58 +00:00
Evan Cheng
358dec5180 Part 1.
- Change register allocation hint to a pair of unsigned integers. The hint type is zero (which means prefer the register specified as second part of the pair) or entirely target dependent.
- Allow targets to specify alternative register allocation orders based on allocation hint.

Part 2.
- Use the register allocation hint system to implement more aggressive load / store multiple formation.
- Aggressively form LDRD / STRD. These are formed *before* register allocation. It has to be done this way to shorten live interval of base and offset registers. e.g.
v1025 = LDR v1024, 0
v1026 = LDR v1024, 0
=>
v1025,v1026 = LDRD v1024, 0

If this transformation isn't done before allocation, v1024 will overlap v1025 which means it more difficult to allocate a register pair.

- Even with the register allocation hint, it may not be possible to get the desired allocation. In that case, the post-allocation load / store multiple pass must fix the ldrd / strd instructions. They can either become ldm / stm instructions or back to a pair of ldr / str instructions.

This is work in progress, not yet enabled.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73381 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-15 08:28:29 +00:00
Evan Cheng
90f95f88c6 Move register allocation preference (or hint) from LiveInterval to MachineRegisterInfo. This allows more passes to set them.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73346 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-14 20:22:55 +00:00
Mike Stump
fe095f39e7 Restore minor deletion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70892 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-04 18:40:41 +00:00
Evan Cheng
c781a243a3 In some rare cases, the register allocator can spill registers but end up not utilizing registers at all. The fundamental problem is linearscan's backtracking can end up freeing more than one allocated registers. However, reloads and restores might be folded into uses / defs and freed registers might not be used at all.
VirtRegMap keeps track of allocations so it knows what's not used. As a horrible hack, the stack coloring can color spill slots with *free* registers. That is, it replace reload and spills with copies from and to the free register. It unfold instructions that load and store the spill slot and replace them with register using variants.

Not yet enabled. This is part 1. More coming.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70787 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-03 18:32:42 +00:00
Bill Wendling
e67f5e4273 Oy! When reverting r68073, I added in experimental code. Sorry...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@68099 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-31 08:41:31 +00:00
Bill Wendling
8fe00540fc Revert r68073. It's causing a failure in the Apple-style builds.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@68092 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-31 08:26:26 +00:00
Daniel Dunbar
cfbf05ef03 Add newlines at end of file (this can annoy gcov)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67000 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-14 01:53:05 +00:00
Owen Anderson
49c8aa0d8b Convert VirtRegMap to a MachineFunctionPass.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66870 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-13 05:55:11 +00:00
Owen Anderson
1ed5b714f1 Reorganization: Move the Spiller out of VirtRegMap.cpp into its own files. No (intended) functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66720 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-11 22:31:21 +00:00
Evan Cheng
0d8fc52ed3 Yet another case where the spiller marked two uses of the same register on the same instruction as kill. This fixes PR3706.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66428 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-09 19:00:05 +00:00
Evan Cheng
821b8560e7 If a MI uses the same register more than once, only mark one of them as 'kill'.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66363 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-08 03:58:35 +00:00
Evan Cheng
c8bb37a50a Last commit accidentially deleted this code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65679 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-28 06:02:14 +00:00
Evan Cheng
04cf3e39f3 The last commit was overly conservative. It's ok to reuse value that's already marked livein.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65498 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-26 03:02:21 +00:00
Evan Cheng
f792352c25 If an available register falls through to a succ block, unset the last kill. Sorry, it's impossible to reduce a sensible test case. It basically requires the moon and stars to align in order to cause a failure.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65497 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-26 02:30:42 +00:00
Evan Cheng
bf18939180 A couple of places where reused use operands should be marked kill. This is exposed by recent availability fallthrough changes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64745 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-17 06:41:03 +00:00
Bill Wendling
92c1e12647 Revert this. It was breaking stuff.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64428 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-13 02:16:35 +00:00
Bill Wendling
54fc7d6714 Turn off the old way of handling debug information in the code generator. Use
the new way, where all of the information is passed on SDNodes and machine
instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64427 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-13 02:01:04 +00:00
Dan Gohman
4ed76e76bb Adjust the sizes for a few SmallVectors to reflect their usage.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64381 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-12 17:29:01 +00:00
Evan Cheng
8679119f4b It's (currently) not safe to keep certain physical registers live across basic blocks, e.g. x86 fp stack registers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64374 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-12 10:32:17 +00:00
Evan Cheng
6d209c413e If availability info is kept when fallthrough into a bb, add the available registers to live-in set.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64372 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-12 09:43:23 +00:00
Evan Cheng
ce7f5a1e50 Remove a bogus assertion. It's possible a live-in available value is used by a previous instruction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64339 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-11 23:41:57 +00:00
Evan Cheng
752272a5e5 Implement PR3495: local spiller optimization. The local spiller can now keep availability information over BB boundaries. It visits BB's in depth first order. After visiting a BB if it find a successor which has a single predecessor it visits the successor next without clearing the availability information. This allows the successor to omit reloads or change them into copies.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64298 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-11 08:24:21 +00:00
Bill Wendling
d62e06c53b Explicitly pass in debug location information to BuildMI.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63599 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-03 02:29:34 +00:00
Evan Cheng
04ee5a1d92 Change TargetInstrInfo::isMoveInstr to return source and destination sub-register indices as well.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62600 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-20 19:12:24 +00:00
Evan Cheng
bbe4105cd7 Fix PR3124: overly strict assert.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60392 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-02 02:15:36 +00:00
Evan Cheng
af42fe36ac Fix PR2898. Spiller delete a store for reuse before it knows for sure the reuse happened.
Patch by Lang Hames!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57720 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-17 20:56:41 +00:00
Evan Cheng
6784598895 Fix a very subtle spiller bug: UpdateKills should not forget to track defs of aliases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57673 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-17 06:16:07 +00:00
Dan Gohman
b8cab9227a Fix command-line option printing to print two spaces where needed,
instead of requiring all "short description" strings to begin with
two spaces. This makes these strings less mysterious, and it fixes
some cases where short description strings mistakenly did not
begin with two spaces.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57521 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-14 20:25:08 +00:00