Commit Graph

257 Commits

Author SHA1 Message Date
Owen Anderson aabe06d92a Reorganization: Move the Spiller out of VirtRegMap.cpp into its own files. No (intended) functionality change.
llvm-svn: 66720
2009-03-11 22:31:21 +00:00
Evan Cheng c544cb0eca Change TargetInstrInfo::isMoveInstr to return source and destination sub-register indices as well.
llvm-svn: 62600
2009-01-20 19:12:24 +00:00
Evan Cheng 8f79775a66 Make linear scan's trivial coalescer slightly more aggressive.
llvm-svn: 62547
2009-01-20 00:16:18 +00:00
Dan Gohman 906152a20f Tidy up #includes, deleting a bunch of unnecessary #includes.
llvm-svn: 61715
2009-01-05 17:59:02 +00:00
Evan Cheng ce3ccc1ea0 - More pre-split fixes: spill slot live interval computation bug; restore point bug.
- If a def is spilt, remember its spill index to allow its reuse.

llvm-svn: 58375
2008-10-29 08:39:34 +00:00
Evan Cheng 938e201528 - Rewrite code that update register live interval that's split.
- Create and update spill slot live intervals.
- Lots of bug fixes.

llvm-svn: 58367
2008-10-29 05:06:14 +00:00
Evan Cheng d0d0317b9a Committing a good chunk of the pre-register allocation live interval splitting pass. It's handling simple cases and appear to do good things. Next: avoid splitting an interval multiple times; renumber registers when possible; record stack slot live intervals for coloring; rematerialize defs when possible.
llvm-svn: 58044
2008-10-23 20:43:13 +00:00
Dan Gohman 9c4b7d5c4f 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.

llvm-svn: 57521
2008-10-14 20:25:08 +00:00
Owen Anderson 1d338fc6a4 Add an option to enable StrongPHIElimination, for ease of testing.
llvm-svn: 57259
2008-10-07 20:22:28 +00:00
Evan Cheng 9156bd2f48 Re-apply 56835 along with header file changes.
llvm-svn: 56848
2008-09-30 15:44:16 +00:00
Duncan Sands 2b9adce1d0 Revert commit 56835 since it breaks the build.
"If a re-materializable instruction has a register
operand, the spiller will change the register operand's
spill weight to HUGE_VAL to avoid it being spilled.
However, if the operand is already in the queue ready
to be spilled, avoid re-materializing it".

llvm-svn: 56837
2008-09-30 10:00:30 +00:00
Evan Cheng 9469049f7d If a re-materializable instruction has a register operand, the spiller will change the register operand's spill weight to HUGE_VAL to avoid it being spilled. However, if the operand is already in the queue ready to be spilled, avoid re-materializing it.
llvm-svn: 56835
2008-09-30 06:36:58 +00:00
Dale Johannesen c36660d756 Next round of earlyclobber handling. Approach the
RA problem by expanding the live interval of an
earlyclobber def back one slot.  Remove
overlap-earlyclobber throughout.  Remove 
earlyclobber bits and their handling from
live internals.

llvm-svn: 56539
2008-09-24 01:07:17 +00:00
Dale Johannesen 9af7b3daec Teach coalescer about earlyclobber bits.
Check bits for preferred register.

llvm-svn: 56384
2008-09-20 02:03:04 +00:00
Evan Cheng c042000649 Fix PR2808. When regalloc runs out of register, it spill a physical register around the live interval being allocated. Do not continue to try to spill another register, just grab the physical register and move on.
llvm-svn: 56381
2008-09-20 01:28:05 +00:00
Dale Johannesen 436aae627d Make earlyclobber stuff work when virtual regs
have previously been assigned conflicting physreg.

llvm-svn: 56364
2008-09-19 18:52:31 +00:00
Dale Johannesen e519bd4183 Remove AsmThatEarlyClobber etc. from LiveIntervalAnalysis
and redo as linked list walk.  Logic moved into RA.
Per review feedback.

llvm-svn: 56326
2008-09-19 01:02:35 +00:00
Evan Cheng 3d9416cf24 Somehow RegAllocLinearScan is keeping two pointers to MachineRegisterInfo.
llvm-svn: 56314
2008-09-18 22:38:47 +00:00
Dale Johannesen f8610ebebc Add a bit to mark operands of asm's that conflict
with an earlyclobber operand elsewhere.  Propagate
this bit and the earlyclobber bit through SDISel.
Change linear-scan RA not to allocate regs in a way 
that conflicts with an earlyclobber.  See also comments.

llvm-svn: 56290
2008-09-17 21:13:11 +00:00
Evan Cheng 53b728c27c Fix PR2757. Ignore liveinterval register allocation preference if the preference register is not in the right register class. This can happen due to sub-register coalescing.
llvm-svn: 56006
2008-09-09 20:22:01 +00:00
Dan Gohman a79db30d28 Tidy up several unbeseeming casts from pointer to intptr_t.
llvm-svn: 55779
2008-09-04 17:05:41 +00:00
Owen Anderson d669b9b671 Convert several std::vectors over to SmallVector, and use reserve() as appropriate for cases where std::vector is still used.
llvm-svn: 54820
2008-08-15 18:49:41 +00:00
Owen Anderson 99e911fb16 Get rid of a use of std::map.
llvm-svn: 54770
2008-08-13 23:36:23 +00:00
Owen Anderson 51f689a652 Make the allocation of LiveIntervals explicit, rather than holding them in the r2iMap_ by value. This will prevent references to them from being invalidated
if the map is changed.

llvm-svn: 54763
2008-08-13 21:49:13 +00:00
Owen Anderson 7c800ad977 Fix a compile-time regression introduced by my heuristic-changing patch. I forgot
to multiply the instruction count by a constant factor in a few places, which
caused the register allocator to require many more iterations.

llvm-svn: 53959
2008-07-23 19:47:27 +00:00
Owen Anderson 029182f3a3 Change the heuristics used in the coalescer, register allocator, and within
live intervals itself to use an instruction count approximation that is 
not affected by inserting empty indices.

llvm-svn: 53937
2008-07-22 22:46:49 +00:00
Dan Gohman 9cc3f68ab1 A brief survey of priority_queue usage in the tree turned this up
as a questionable case, but the code isn't actually needed.

llvm-svn: 52657
2008-06-23 23:51:16 +00:00
Evan Cheng efc67e78d7 Enhanced heuristic to determine the *best* register to spill. Instead of picking the register with the lowest spill weight. Consider (up to) 2 additional registers with spill weights that are close to the lowest spill weight. The one with fewest defs and uses that conflicts with the current interval (weighted by loop depth) is the spill candidate.
This is not always a win, but there are much more wins than loses and wins tend to be more noticeable.

llvm-svn: 52554
2008-06-20 21:45:16 +00:00
Evan Cheng 6d7a144453 Refine stack slot interval weight computation.
llvm-svn: 52040
2008-06-06 07:54:39 +00:00
Evan Cheng 12a0222a01 Add a stack slot coloring pass. Not yet enabled.
llvm-svn: 51934
2008-06-04 09:18:41 +00:00
Evan Cheng 305d268ac3 Do not add empty live intervals to handled_. They should never be undone for backtracking.
llvm-svn: 49544
2008-04-11 17:55:47 +00:00
Evan Cheng 6d07b625aa Special handling of zero-sized live intervals.
llvm-svn: 49167
2008-04-03 16:40:27 +00:00
Evan Cheng 6e225173c5 Add an assertion to catch register of illegal class.
llvm-svn: 48751
2008-03-24 23:28:21 +00:00
Evan Cheng e21a68bca7 Undo tweak. It had no obvious benefit.
llvm-svn: 48341
2008-03-13 17:42:48 +00:00
Evan Cheng e88a625ecd When the register allocator runs out of registers, spill a physical register around the def's and use's of the interval being allocated to make it possible for the interval to target a register and spill it right away and restore a register for uses. This likely generates terrible code but is before than aborting.
llvm-svn: 48218
2008-03-11 07:19:34 +00:00
Evan Cheng 850e143cbf Temporarily revert 48175.
llvm-svn: 48204
2008-03-11 00:27:34 +00:00
Evan Cheng 7abdb438a1 If the register allocator ran out of registers, just abort for now.
llvm-svn: 48175
2008-03-10 21:27:20 +00:00
Chris Lattner d6bd311506 Use a smallvector for inactiveCounts and initialize it lazily
instead of init'ing it maximally to zeros on entry.  getFreePhysReg
is pretty hot and only a few elements are typically used.  This speeds
up linscan by 5% on 176.gcc.

llvm-svn: 47631
2008-02-26 22:08:41 +00:00
Bill Wendling d7a258d325 Rename PrintableName to Name.
llvm-svn: 47629
2008-02-26 21:47:57 +00:00
Bill Wendling c24ea4fb41 Change "Name" to "AsmName" in the target register info. Gee, a refactoring tool
would have been a Godsend here!

llvm-svn: 47625
2008-02-26 21:11:01 +00:00
Anton Korobeynikov 18991d78fa Fix newly-introduced 4.3 warnings
llvm-svn: 47375
2008-02-20 12:07:57 +00:00
Dan Gohman 3a4be0fdef Rename MRegisterInfo to TargetRegisterInfo.
llvm-svn: 46930
2008-02-10 18:45:23 +00:00
Bill Wendling 0c209430b4 Don't recalculate the loop info and loop dominators analyses if they're
preserved.

llvm-svn: 45596
2008-01-04 20:54:55 +00:00
Chris Lattner a10fff51d9 Rename SSARegMap -> MachineRegisterInfo in keeping with the idea
that "machine" classes are used to represent the current state of
the code being compiled.  Given this expanded name, we can start 
moving other stuff into it.  For now, move the UsedPhysRegs and
LiveIn/LoveOuts vectors from MachineFunction into it.

Update all the clients to match.

This also reduces some needless #includes, such as MachineModuleInfo
from MachineFunction.

llvm-svn: 45467
2007-12-31 04:13:23 +00:00
Chris Lattner f3ebc3f3d2 Remove attribution from file headers, per discussion on llvmdev.
llvm-svn: 45418
2007-12-29 20:36:04 +00:00
Evan Cheng 303417d242 Switch over to MachineLoopInfo.
llvm-svn: 44838
2007-12-11 02:09:15 +00:00
Evan Cheng 8e22379303 Live interval splitting:
When a live interval is being spilled, rather than creating short, non-spillable
intervals for every def / use, split the interval at BB boundaries. That is, for
every BB where the live interval is defined or used, create a new interval that
covers all the defs and uses in the BB.

This is designed to eliminate one common problem: multiple reloads of the same
value in a single basic block. Note, it does *not* decrease the number of spills
since no copies are inserted so the split intervals are *connected* through
spill and reloads (or rematerialization). The newly created intervals can be
spilled again, in that case, since it does not span multiple basic blocks, it's
spilled in the usual manner. However, it can reuse the same stack slot as the
previously split interval.

This is currently controlled by -split-intervals-at-bb.

llvm-svn: 44198
2007-11-17 00:40:40 +00:00
Bill Wendling b3712f8146 Adding debug output during coalescing.
llvm-svn: 44154
2007-11-15 02:06:30 +00:00
Bill Wendling 8269925b1e Need to increment the iterator.
llvm-svn: 44153
2007-11-15 00:40:48 +00:00
Evan Cheng be51f28e2b Refactor some code.
llvm-svn: 44010
2007-11-12 06:35:08 +00:00
Evan Cheng 5c1b044899 If an interval is being undone clear its preference as well since the source interval may have been undone as well.
llvm-svn: 43670
2007-11-04 08:32:21 +00:00
Evan Cheng 66298e226f There are times when the coalescer would not coalesce away a copy but the copy
can be eliminated by the allocator is the destination and source targets the
same register. The most common case is when the source and destination registers
are in different class. For example, on x86 mov32to32_ targets GR32_ which
contains a subset of the registers in GR32.

The allocator can do 2 things:
1. Set the preferred allocation for the destination of a copy to that of its source.
2. After allocation is done, change the allocation of a copy destination (if
   legal) so the copy can be eliminated.

This eliminates 443 extra moves from 403.gcc.

llvm-svn: 43662
2007-11-03 07:20:12 +00:00
Evan Cheng 0dde6e5761 Apply Chris' suggestions.
llvm-svn: 43069
2007-10-17 06:53:44 +00:00
Evan Cheng a6fd8bc97e Clean up code that calculate MBB live-in's.
llvm-svn: 43061
2007-10-17 02:12:22 +00:00
Evan Cheng 8f644cef0f Some clean up.
llvm-svn: 43043
2007-10-16 21:09:14 +00:00
Evan Cheng 89d5916921 Some clean up.
llvm-svn: 42898
2007-10-12 08:45:27 +00:00
David Greene 65d2a697dc Pluggable coalescers inplementation.
llvm-svn: 41743
2007-09-06 16:18:45 +00:00
Evan Cheng 33820da1da Re-implement trivial rematerialization. This allows def MIs whose live intervals that are coalesced to be rematerialized.
llvm-svn: 41060
2007-08-13 23:45:17 +00:00
David Greene 02f6e9b621 Factor live variable analysis so it does not do register coalescing
simultaneously.  Move that pass to SimpleRegisterCoalescing.

This makes it easier to implement alternative register allocation and
coalescing strategies while maintaining reuse of the existing live
interval analysis.

llvm-svn: 37520
2007-06-08 17:18:56 +00:00
Bill Wendling 31fd60ba0c Change names from RA to something unique to get rid of naming conflicts with
certain linkers...

llvm-svn: 36944
2007-05-08 19:02:46 +00:00
Devang Patel 8c78a0bff0 Drop 'const'
llvm-svn: 36662
2007-05-03 01:11:54 +00:00
Devang Patel e95c6ad802 Use 'static const char' instead of 'static const int'.
Due to darwin gcc bug, one version of darwin linker coalesces
static const int, which defauts PassID based pass identification.

llvm-svn: 36652
2007-05-02 21:39:20 +00:00
Devang Patel 09f162ca6a Do not use typeinfo to identify pass in pass manager.
llvm-svn: 36632
2007-05-01 21:15:47 +00:00
Evan Cheng 0ba174534c Match MachineFunction::UsedPhysRegs changes.
llvm-svn: 36452
2007-04-25 22:13:27 +00:00
Evan Cheng 11dc5abde1 Clean up.
llvm-svn: 36431
2007-04-25 07:18:20 +00:00
Evan Cheng b881bdabd9 Copy coalescing change to prevent a physical register from being pin to a
long live interval that has low usage density.
1. Change order of coalescing to join physical registers with virtual
   registers first before virtual register intervals become too long.
2. Check size and usage density to determine if it's worthwhile to join.
3. If joining is aborted, assign virtual register live interval allocation
   preference field to the physical register.
4. Register allocator should try to allocate to the preferred register
   first (if available) to create identify moves that can be eliminated.

llvm-svn: 36218
2007-04-17 20:32:26 +00:00
Evan Cheng 0e3278e505 First cut trivial re-materialization support.
llvm-svn: 35208
2007-03-20 08:13:50 +00:00
Evan Cheng 220a7af107 Only add liveinterval to livein set if it isn't assigned a stack slot.
llvm-svn: 34593
2007-02-25 09:39:02 +00:00
Evan Cheng f7ed82da10 Re-apply my liveintervalanalysis changes. Now with PR1207 fixes.
llvm-svn: 34428
2007-02-19 21:49:54 +00:00
Reid Spencer da81bf4d3e For PR1207:
Revert patches that caused the problem. Evan, please investigate and reapply
when you've discovered the problem.

llvm-svn: 34399
2007-02-19 03:20:00 +00:00
Evan Cheng a3d3599210 Do not add livein's to entry MBB twice.
llvm-svn: 34382
2007-02-17 11:11:27 +00:00
Evan Cheng 7238410766 Add live-ins to every BB.
llvm-svn: 34342
2007-02-16 09:05:02 +00:00
Chris Lattner aee775a6b7 Eliminate static ctors from Statistics
llvm-svn: 32698
2006-12-19 22:41:21 +00:00
Chris Lattner 700b873130 Detemplatize the Statistic class. The only type it is instantiated with
is 'unsigned'.

llvm-svn: 32279
2006-12-06 17:46:33 +00:00
Chris Lattner 979804d800 eliminate fp statistic
llvm-svn: 32251
2006-12-06 01:48:55 +00:00
Jeff Cohen cc08c83186 Unbreak VC++ build.
llvm-svn: 32113
2006-12-02 02:22:01 +00:00
Bill Wendling d108b9a60d Replace std::cerr uses of the "DEBUG" macro with "DOUT" instead. Removes
a #include of iostream.

llvm-svn: 31800
2006-11-17 00:50:36 +00:00
Jim Laskey 61feeb90f9 Remove redundant <cmath>.
llvm-svn: 31561
2006-11-08 19:16:44 +00:00
Jim Laskey 6a9342166b Use correct value for float HUGH_VAL.
llvm-svn: 31500
2006-11-07 12:25:45 +00:00
Jim Laskey a916192267 LinearScanner hotspot.
llvm-svn: 31153
2006-10-24 14:35:25 +00:00
Chris Lattner 3d27be1333 s|llvm/Support/Visibility.h|llvm/Support/Compiler.h|
llvm-svn: 29911
2006-08-27 12:54:02 +00:00
Jim Laskey 29e635d3c9 Final polish on machine pass registries.
llvm-svn: 29471
2006-08-02 12:30:23 +00:00
Jim Laskey 95eda5b1f3 Introducing plugable register allocators and instruction schedulers.
llvm-svn: 29434
2006-08-01 14:21:23 +00:00
Andrew Lenharth c496b418b5 Reduce number of exported symbols
llvm-svn: 29220
2006-07-20 17:28:38 +00:00
Chris Lattner e097e6f7c7 Shave another 27K off libllvmgcc.dylib with visibility hidden
llvm-svn: 28973
2006-06-28 22:17:39 +00:00
Evan Cheng a726fc6dbf If the register allocator cannot find a register to spill, try the aliases. If
that still fails (because all the register spill weights are inf), just grab
one.

llvm-svn: 28262
2006-05-12 19:07:46 +00:00
Evan Cheng db6aa4896b Backing out previous check-in.
llvm-svn: 28219
2006-05-11 07:28:16 +00:00
Evan Cheng 6ad040a6bc If the live interval legnth is essentially zero, i.e. in every live range
the use follows def immediately, it doesn't make sense to spill it and
hope it will be easier to allocate for this LI.

llvm-svn: 28217
2006-05-10 22:30:41 +00:00
Chris Lattner b6e2d0027a Add some comments.
llvm-svn: 27133
2006-03-25 23:00:56 +00:00
Chris Lattner 2988921dc4 Code cleanups, no functionality change
llvm-svn: 26328
2006-02-23 06:44:17 +00:00
Chris Lattner de02d7727f Add explicit #includes of <iostream>
llvm-svn: 25515
2006-01-22 23:41:00 +00:00
Duraid Madina e47d9d0e92 HB is *the* code janitor.
llvm-svn: 25031
2005-12-28 04:55:42 +00:00
Duraid Madina f28b3bd8b4 I think I know what you meant here, but just to be safe I'll let you
do it. :)

    <_sabre_> excuses excuses

llvm-svn: 24471
2005-11-21 14:09:40 +00:00
Chris Lattner 2ea5c99eca Add section switching to common code generator code. Add a couple of
asserts.

llvm-svn: 24445
2005-11-21 07:06:27 +00:00
Chris Lattner b1f8982ff0 Expose the LiveInterval interfaces as public headers.
llvm-svn: 23400
2005-09-21 04:19:09 +00:00
Chris Lattner 4d602bed10 When checking the fixed intervals, don't forget to check for register aliases.
This fixes PR621 and Regression/CodeGen/X86/2005-08-30-RegAllocAliasProblem.ll

llvm-svn: 23158
2005-08-30 21:03:36 +00:00
Chris Lattner 22e91cc3b5 Keep track of which registers are related to which other registers.
Use this information to avoid doing expensive interval intersections for
registers that could not possible be interesting.  This speeds up linscan
on ia64 compiling kc++ in release mode from taking 7.82s to 4.8s(!), total
itanium llc time on this program is 27.3s now.  This marginally speeds up
PPC and X86, but they appear to be limited by other parts of linscan, not
this code.

On this program, on itanium, live intervals now takes 41% of llc time.

llvm-svn: 22986
2005-08-23 22:27:31 +00:00
Chris Lattner 834a2316a3 Try to avoid scanning the fixed list. On architectures with a non-stupid
number of regs (e.g. most riscs), many functions won't need to use callee
clobbered registers.  Do a speculative check to see if we can get a free
register without processing the fixed list (which has all of these).  This
saves a lot of time on machines with lots of callee clobbered regs (e.g.
ppc and itanium, also x86).

This reduces ppc llc compile time from 184s -> 172s on kc++.  This is probably
worth FAR FAR more on itanium though.

llvm-svn: 22972
2005-08-22 20:59:30 +00:00
Chris Lattner 95a157ae1a Move some code in the register assignment case that only needs to happen if
we spill out of the fast path.  The scan of active_ and the calls to
updateSpillWeights don't need to happen unless a spill occurs.  This reduces
debug llc time of kc++ with ppc from 187.3s to 183.2s.

llvm-svn: 22971
2005-08-22 20:20:42 +00:00
Chris Lattner 83b821b584 Speed up this loop a bit, based on some observations that Nate made, and
add some comments.  This loop really needs to be reevaluated!

llvm-svn: 22966
2005-08-22 16:55:22 +00:00