Commit Graph

67 Commits

Author SHA1 Message Date
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
1088317675 Remove #include<map> from LiveVariables.h. Not referenced.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49099 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-02 17:23:50 +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
fe666a3592 Improve VarInfo::removeKill() by using std::find instead of linear search.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48321 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-13 02:42:55 +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
5ec3ab7f67 Fixed typo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47365 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-20 09:14:09 +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
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
Dan Gohman
35e9f7d711 Fix a typo in a comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46588 91177308-0d34-0410-b5e6-96231b3b80d8
2008-01-31 00:44:33 +00:00
Dan Gohman
6326b0d0f8 Fix a typo in a comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46507 91177308-0d34-0410-b5e6-96231b3b80d8
2008-01-29 12:06:33 +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
Evan Cheng
426df7538d Unbreak the build.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46021 91177308-0d34-0410-b5e6-96231b3b80d8
2008-01-15 22:19:35 +00:00
Chris Lattner
f73823000e More cleanups for MachineOperand:
- Eliminate the static "print" method for operands, moving it
    into MachineOperand::print.
  - Change various set* methods for register flags to take a bool
    for the value to set it to.  Remove unset* methods.
  - Group methods more logically by operand flavor in MachineOperand.h


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45461 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-30 21:56:09 +00:00
Chris Lattner
7ed47a1335 Don't attribute in file headers anymore. See llvmdev for the
discussion of this change.  Boy are my fingers tired. ;-)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45411 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-29 19:59:42 +00:00
Evan Cheng
81a0382181 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44198 91177308-0d34-0410-b5e6-96231b3b80d8
2007-11-17 00:40:40 +00:00
Owen Anderson
fc8663dbe0 Oops, forgot to commit this file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43867 91177308-0d34-0410-b5e6-96231b3b80d8
2007-11-08 01:22:24 +00:00
Dan Gohman
92dfe2001e Remove isReg, isImm, and isMBB, and change all their users to use
isRegister, isImmediate, and isMachineBasicBlock, which are equivalent,
and more popular.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41958 91177308-0d34-0410-b5e6-96231b3b80d8
2007-09-14 20:33:02 +00:00
Dan Gohman
c674a924d4 Don't assume that only Uses can be kills. Defs are marked as kills initially
when there are no uses. This fixes a dangling-pointer bug, where pointers to
deleted instructions were not removed from kills lists. More info here:
http://lists.cs.uiuc.edu/pipermail/llvmdev/2007-July/009749.html


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40131 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-20 23:17:34 +00:00
Evan Cheng
4efe74129f Properly handle kills of a physical register which has sub-registers that are read by later instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37739 91177308-0d34-0410-b5e6-96231b3b80d8
2007-06-26 21:03:35 +00:00
Evan Cheng
56184904cd Eliminate MarkVirtRegAliveInBlock recursion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36943 91177308-0d34-0410-b5e6-96231b3b80d8
2007-05-08 19:00:00 +00:00
Nick Lewycky
ecd94c804a Fix typo in comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36873 91177308-0d34-0410-b5e6-96231b3b80d8
2007-05-06 13:37:16 +00:00
Devang Patel
1997473cf7 Drop 'const'
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36662 91177308-0d34-0410-b5e6-96231b3b80d8
2007-05-03 01:11:54 +00:00
Devang Patel
3e15bf33e0 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36652 91177308-0d34-0410-b5e6-96231b3b80d8
2007-05-02 21:39:20 +00:00
Devang Patel
794fd75c67 Do not use typeinfo to identify pass in pass manager.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36632 91177308-0d34-0410-b5e6-96231b3b80d8
2007-05-01 21:15:47 +00:00
Evan Cheng
05350288a6 Be careful when to add implicit kill / dead operands. Don't add them during / post reg-allocation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36458 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-26 01:40:09 +00:00
Evan Cheng
e96f50142e Data structure change to improve compile time (especially in debug mode).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36447 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-25 19:34:00 +00:00
Evan Cheng
24a3cc4c83 Fix for PR1306.
- A register def / use now implicitly affects sub-register liveness but does
not affect liveness information of super-registers.
- Def of a larger register (if followed by a use later) is treated as
read/mod/write of a smaller register.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36434 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-25 07:30:23 +00:00
Evan Cheng
f44c72817e VarInfo::UsedBlocks is no longer used. Remove.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36250 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-18 05:04:38 +00:00
Evan Cheng
38b7ca6651 Keep track of number of uses within the function per virtual register.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36214 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-17 20:22:11 +00:00
Evan Cheng
c6a2410d58 Track the BB's where each virtual register is used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35135 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-17 09:29:54 +00:00
Evan Cheng
b371f457b0 Re-apply my liveintervalanalysis changes. Now with PR1207 fixes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34428 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-19 21:49:54 +00:00
Reid Spencer
a284cbf667 For PR1207:
Revert patches that caused the problem. Evan, please investigate and reapply
when you've discovered the problem.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34399 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-19 03:20:00 +00:00
Evan Cheng
64ff3c349b Allow LiveVariables to track liveness of more registers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34377 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-17 11:07:08 +00:00
Evan Cheng
61de82d885 Use BitVector instead of vector<bool> which can be extremely slow.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34302 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-15 05:59:24 +00:00
Evan Cheng
a6c4c1eb90 Do away with kill / dead maps. Move kill / dead info onto MI's.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31759 91177308-0d34-0410-b5e6-96231b3b80d8
2006-11-15 20:51:59 +00:00
Bill Wendling
f7da4e939f Fix for PR929. The PHI nodes were being gone through for each instruction
in a successor block for every block...resulting in some O(N^k) algorithm
which wasn't very good for performance. Calculating this information up
front and keeping it in a map made it much faster.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30697 91177308-0d34-0410-b5e6-96231b3b80d8
2006-10-03 07:20:20 +00:00
Chris Lattner
7a3abdc63c Move two methods out of line, make them work when the record for a machine
instruction includes physregs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30061 91177308-0d34-0410-b5e6-96231b3b80d8
2006-09-03 00:05:09 +00:00
Chris Lattner
51d6e76ff4 add a comment that I should have written a long time ago
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25084 91177308-0d34-0410-b5e6-96231b3b80d8
2006-01-04 07:29:33 +00:00
Chris Lattner
0df687b1be add a dump method to help debugging
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25079 91177308-0d34-0410-b5e6-96231b3b80d8
2006-01-04 05:39:51 +00:00
Chris Lattner
4e27d3a10c Fix a problem Duraid noticed, where we weren't removing values from the kills
list when doing two-address and phi node lowering during register allocation.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23043 91177308-0d34-0410-b5e6-96231b3b80d8
2005-08-25 05:45:31 +00:00
Chris Lattner
c44fff472c Keep the killed/dead sets sorted, so that "KillsRegister" can do a quick
binary search to test for membership.  This speeds up LLC a bit more on KC++,
e.g. on itanium from 16.6974s to 14.8272s, PPC from 11.4926s to 10.7089s and
X86 from 10.8128s to 9.7943s, with no difference in generated code (like all
of the RA patches).

With these changes, isel is the slowest pass for PPC/X86, but linscan+live
intervals is still > 50% of the compile time for itanium.  More work could
be done, but this is the last for now.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22993 91177308-0d34-0410-b5e6-96231b3b80d8
2005-08-24 00:09:02 +00:00
Chris Lattner
e0cbf970ac Change live variables from using multimaps to using maps of vectors and
rearrange some of the accessors to be more efficient.

This makes it much more efficient to iterate over all of the things with the
same value.  This speeds up liveintervals analysis from 8.63s to 3.79s with
a release build of llc on kc++ with -march=ia64.  This also speeds up live
var from 1.66s -> 0.87s as well, reducing total llc time from 20.1s->15.2s.

This also speeds up other targets slightly, e.g. llc time on X86 from 16.84
-> 16.45s, and PPC from 17.64->17.03s.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22990 91177308-0d34-0410-b5e6-96231b3b80d8
2005-08-23 23:40:41 +00:00
Chris Lattner
20647a55bf Add RegisterDefIsDead to correspond to KillsRegister, mark both const
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22987 91177308-0d34-0410-b5e6-96231b3b80d8
2005-08-23 22:43:24 +00:00
Misha Brukman
00876a2808 Convert tabs to spaces
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21438 91177308-0d34-0410-b5e6-96231b3b80d8
2005-04-22 03:46:24 +00:00
Misha Brukman
ea61c35872 Remove trailing whitespace
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21409 91177308-0d34-0410-b5e6-96231b3b80d8
2005-04-21 20:39:54 +00:00
Chris Lattner
801abe663f Add a useful accessor
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@19209 91177308-0d34-0410-b5e6-96231b3b80d8
2005-01-01 15:58:55 +00:00
Alkis Evlogimenos
22a2f6d5b0 Use newly added API in MRegisterInfo and don't expose the allocatable
register set anymore. Its users now use the MRegisterInfo API.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16061 91177308-0d34-0410-b5e6-96231b3b80d8
2004-08-26 22:23:32 +00:00
Chris Lattner
74de8b1b26 There is no need to store the MBB along with the MI any more, we can now
ask instructions for their parent.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@14998 91177308-0d34-0410-b5e6-96231b3b80d8
2004-07-19 07:04:55 +00:00