Commit Graph

150 Commits

Author SHA1 Message Date
Alkis Evlogimenos
843b160a20 Eliminate the use of spill (reserved) registers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11476 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-15 10:24:21 +00:00
Alkis Evlogimenos
6ab5c15962 Use std::numeric_limits<float>::infinity() instead of
std::numeric_limits<float>::max() for weighting preallocated
intervals.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11427 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-14 00:44:07 +00:00
Alkis Evlogimenos
be766c7246 Remove getAllocatedRegNum(). Use getReg() instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11393 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-13 21:01:20 +00:00
Alkis Evlogimenos
c0b9dc5be7 Change MachineBasicBlock's vector of MachineInstr pointers into an
ilist of MachineInstr objects. This allows constant time removal and
insertion of MachineInstr instances from anywhere in each
MachineBasicBlock. It also allows for constant time splicing of
MachineInstrs into or out of MachineBasicBlocks.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11340 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-12 02:27:10 +00:00
Chris Lattner
1cbe4d0ad0 Do not use MachineOperand::isVirtualRegister either!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11283 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-10 21:12:22 +00:00
Alkis Evlogimenos
0b8cb2bc47 Change live interval representation. Machine instructions now have two
slots each. As a concequence they get numbered as 0, 2, 4 and so
on. The first slot is used for operand uses and the second for
defs. Here's an example:

0: A = ...
2: B = ...
4: C = A + B ;; last use of A

The live intervals should look like:

A = [1, 5)
B = [3, x)
C = [5, y)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11141 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-05 22:55:25 +00:00
Alkis Evlogimenos
ad48cd6327 We don't need to scan the blocks that we are live-in on every
access. Rather we only have to do it on the creation of the interval.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11135 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-05 20:45:40 +00:00
Alkis Evlogimenos
b606eaca1b Should be more careful. The previously applied change made all counts
outside of loops = 0.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11085 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-02 20:29:57 +00:00
Alkis Evlogimenos
b180e3e92b Change string for joined intervals.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11057 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-01 16:13:05 +00:00
Alkis Evlogimenos
b0b0ebaac0 Change xor to ^.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11054 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-01 08:19:25 +00:00
Alkis Evlogimenos
676cf8cb1d Missed one silly assert :-)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11048 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-01 02:21:31 +00:00
Alkis Evlogimenos
01e74a2aab Simplify joinIntervals() code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11047 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-01 02:18:31 +00:00
Alkis Evlogimenos
4f67b86648 Use MRegisterInfo::isPhysicalRegister and
MRegisterInfo::isVirtualRegister.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11045 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-01 01:27:01 +00:00
Alkis Evlogimenos
52220f61bb Apply final part of Chris' patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11040 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-31 23:48:47 +00:00
Alkis Evlogimenos
02ba13c989 Be a little smarter on the way we handle physical register defs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11038 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-31 23:13:30 +00:00
Alkis Evlogimenos
08cec00588 Merge safe parts from last night's buggy commit. These do not break
any test cases :-)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11032 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-31 19:59:32 +00:00
Alkis Evlogimenos
97017de187 Optimize liveAt() and overlaps(). We now use a binary search instead
of a linear search to find the first range for comparisons. This cuts
down the linear scan register allocator running time by a factor of 3
in 254.perlbmk and by a factor of 2.2 in 176.gcc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11030 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-31 16:54:54 +00:00
Alkis Evlogimenos
4d46e1e521 Revert last night's changes as they broke some tests. Will remerge parts of the patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11029 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-31 14:37:41 +00:00
Alkis Evlogimenos
32bdd4ea65 Several performance enhancements and cleanups from Chris.
Simplification of LiveIntervals::Interval::overlaps() and addition of
examples to overlaps() and liveAt() to make them clearer.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11028 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-31 04:56:07 +00:00
Alkis Evlogimenos
79b0c3f0b9 Fix failing test cases with joined live intervals. It turns out that
when joining we need to check if we overlap with the second interval
or any of its aliases.

Also make joining intervals the default.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10973 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-23 13:37:51 +00:00
Alkis Evlogimenos
e88280a422 Add option to join live intervals. Two intervals are joined if there
is a move between two registers, at least one of the registers is
virtual and the two live intervals do not overlap.

This results in about 40% reduction in intervals, 30% decrease in the
register allocators running time and a 20% increase in peephole
optimizations (mainly move eliminations).

The option can be enabled by passing -join-liveintervals where
appropriate.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10965 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-22 23:08:45 +00:00
Alkis Evlogimenos
1075ecd32f Revert previous change. The code was correct...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10957 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-22 19:17:52 +00:00
Alkis Evlogimenos
e1a210777d Fix incorrect negatives in LiveIntervals::Interval::liveAt().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10956 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-22 18:33:50 +00:00
Alkis Evlogimenos
1893a05b28 Add asserts to previous change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10893 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-16 16:23:23 +00:00
Alkis Evlogimenos
f5f1689ed2 Use a list instead of a vector to store intervals. This will be needed
when we join intervals and one of the two will need to be removed.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10892 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-16 16:06:59 +00:00
Alkis Evlogimenos
d6e40a6cbc Properly update #intervals statistic.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10847 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-14 10:44:29 +00:00
Alkis Evlogimenos
9739736b94 Fix bug in LiveIntervals::Interval::overlaps and
LiveIntervals::Interval::liveAt. Both were considering the live ranges
closed in the end, when they are actually open.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10835 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-14 00:20:09 +00:00
Alkis Evlogimenos
af25473d5e Fix miscomputation of live intervals. The catch is that registers can
be dead at the defining instruction but can only be killed in
subsequent ones.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10833 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-13 22:26:14 +00:00
Alkis Evlogimenos
1a119e2410 Remove allocatable registers vector. It is already provided by
LiveVariables.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10830 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-13 22:10:43 +00:00
Alkis Evlogimenos
a3a6524965 Cleanup debugging output.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10824 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-13 21:53:20 +00:00
Alkis Evlogimenos
63841bc85d Fix output of live intervals to show correctly its closed, open
ranges, i.e. [a,b)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10822 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-13 21:17:47 +00:00
Alkis Evlogimenos
19b6486d38 Correctly compute live variable information for physical registers
when an implicitely defined register is later used by an alias. For example:

         call foo
         %reg1024 = mov %AL

The call implicitely defines EAX but only AL is used. Before this fix
no information was available on AL. Now EAX and all its aliases except
AL get defined and die at the call instruction whereas AL lives to be
killed by the assignment.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10813 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-13 06:24:30 +00:00
Alkis Evlogimenos
80b378cf7c Change implementation of LiveIntervals::overlap(). This results in a
30-50% decrease in running time of the linear scan register allocator.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10707 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-07 01:45:58 +00:00
Alkis Evlogimenos
63caedf046 Remove simple coalescing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10695 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-05 08:24:57 +00:00
Alkis Evlogimenos
26bfc08b80 Add coalescing to register allocator. A hint is added to each interval
which denotes the register we would like to be assigned to (virtual or
physical). In register allocation, if this hint exists and we can map
it to a physical register (it is either a physical register or it is a
virtual register that already got assigned to a physical one) we use
that register if it is available instead of a random one in the free
pool.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10634 91177308-0d34-0410-b5e6-96231b3b80d8
2003-12-28 17:58:18 +00:00
Alkis Evlogimenos
7a40eaacee Do a separate pass to compute spill weights because doing it inline
with live intervals was missing registers that were used before they
were defined (in the arbitrary order live intervals numbers
instructions).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10603 91177308-0d34-0410-b5e6-96231b3b80d8
2003-12-24 15:44:53 +00:00
Alkis Evlogimenos
056063e264 Fix crash when compiling twolf.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10584 91177308-0d34-0410-b5e6-96231b3b80d8
2003-12-22 13:54:29 +00:00
Alkis Evlogimenos
6b4edbaaf9 Change weight into a float so that we can take into account the
nesting level when computing it. Right now the allocator uses:

    w = sum_over_defs_uses( 10 ^ nesting level );


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10569 91177308-0d34-0410-b5e6-96231b3b80d8
2003-12-21 20:19:10 +00:00
Alkis Evlogimenos
169cfd0196 Add support for inactive intervals. This effectively reuses registers
for live ranges that fall into assigned registers' holes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10566 91177308-0d34-0410-b5e6-96231b3b80d8
2003-12-21 05:43:40 +00:00
Alkis Evlogimenos
4c080863de Remove TwoAddressInstruction from the public headers and add an ID
instead, since this pass doesn't expose any state to its users.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10520 91177308-0d34-0410-b5e6-96231b3b80d8
2003-12-18 22:40:24 +00:00
Alkis Evlogimenos
a71e05acdd Modify linear scan register allocator to use the two-address
instruction pass. This also fixes all remaining bugs for this new
allocator to pass all tests under test/Programs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10515 91177308-0d34-0410-b5e6-96231b3b80d8
2003-12-18 13:15:02 +00:00
Alkis Evlogimenos
43f692f90f When a variable is killed and redifined in a basic block only one
killing instruction is tracked. This causes the LiveIntervals to
create bogus intervals. The workaound is to add a range to the
interval from the redefinition to the end of the basic block.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10510 91177308-0d34-0410-b5e6-96231b3b80d8
2003-12-18 08:53:43 +00:00
Alkis Evlogimenos
dd2cc65f34 Handle multiple virtual register definitions gracefully.
Move some of the longer LiveIntervals::Interval method out of the
header and add debug information to them. Fix bug and simplify range
merging code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10509 91177308-0d34-0410-b5e6-96231b3b80d8
2003-12-18 08:48:48 +00:00
Alkis Evlogimenos
f6f91bf668 Change preserve all claim to just preserve live variables and phielimination.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10469 91177308-0d34-0410-b5e6-96231b3b80d8
2003-12-15 04:55:38 +00:00
Alkis Evlogimenos
4d7af65903 Change interface of MachineOperand as follows:
a) remove opIsUse(), opIsDefOnly(), opIsDefAndUse()
    b) add isUse(), isDef()
    c) rename opHiBits32() to isHiBits32(),
              opLoBits32() to isLoBits32(),
              opHiBits64() to isHiBits64(),
              opLoBits64() to isLoBits64().

This results to much more readable code, for example compare
"op.opIsDef() || op.opIsDefAndUse()" to "op.isDef()" a pattern used
very often in the code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10461 91177308-0d34-0410-b5e6-96231b3b80d8
2003-12-14 13:24:17 +00:00
Alkis Evlogimenos
4c214d2bf0 Ignore non-allocatable physical registers in live interval analysis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10449 91177308-0d34-0410-b5e6-96231b3b80d8
2003-12-13 11:11:02 +00:00
Alkis Evlogimenos
9435eda699 Handle explicit physical register defs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10445 91177308-0d34-0410-b5e6-96231b3b80d8
2003-12-13 05:26:39 +00:00
Alkis Evlogimenos
b27ef248f5 Move operator<<(std::ostream&, const LiveInterval&) out of the header file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10290 91177308-0d34-0410-b5e6-96231b3b80d8
2003-12-05 10:38:28 +00:00
Alkis Evlogimenos
91ceae6d20 Sort live intervals by increasing start point.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10289 91177308-0d34-0410-b5e6-96231b3b80d8
2003-12-05 10:32:01 +00:00
Alkis Evlogimenos
ff0cbe175d Merging the linear scan register allocator in trunk. It currently passes most tests under test/Programs/SingleSource/Benchmarks/Shootout so development will continue on trunk. The allocator is not enabled by default. You will need to pass -regallo=linearscan to lli or llc to use it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10103 91177308-0d34-0410-b5e6-96231b3b80d8
2003-11-20 03:32:25 +00:00