This fixes PR621 and Regression/CodeGen/X86/2005-08-30-RegAllocAliasProblem.ll

llvm-svn: 23158

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

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

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

add some comments.  This loop really needs to be reevaluated!

llvm-svn: 22966

llvm-svn: 21420

llvm-svn: 19791

llvm-svn: 19385

llvm-svn: 18955

20%, shaving 0.1s off hbd compile time on my g5.  Yay.

llvm-svn: 18592

* Do not put fixed registers into the unhandled set.  This means they will
  never find their way into the inactive, active, or handled sets, so we
  can simplify a bunch of code.

llvm-svn: 17945

intersecting an interval.

llvm-svn: 17939

search physreg intervals every time we access it.  This takes another
half second off of linscan.

llvm-svn: 17937

the iterator hints we have to speed up overlaps().  This speeds linscan up
by about .2s (out of 8.7) on 175.vpr for PPC.

llvm-svn: 17935

* Eliminate the releaseMemory method, this is not an analysis
* Change the fixed, active, and inactive lists of intervals to maintain an
  iterator for the current position in the interval.  This allows us to do
  constant time increments of the iterator instead of having to do a binary
  search to find our liverange in our liveinterval all of the time, which
  substantially speeds up cases where LiveIntervals have many LiveRanges
  - which is very common for physical registers.  On targets with many
  physregs, this can make a noticable difference.

  With a release build of LLC for PPC, this halves the time in
  processInactiveIntervals and processActiveIntervals, from 1.5s to .75s.

  This also lays the ground for more to come.

llvm-svn: 17933

iterator/begin/end members.

llvm-svn: 17930

llvm-svn: 17483

the beginning of processing the next one.

llvm-svn: 16605

Patch contributed by Paolo Invernizzi!

llvm-svn: 16152

free allocatable register, we prefer the a free one with the most uses
of inactive intervals. This causes less spills and performes a bit
better compared to gcc:

Program                 | GCC/LLC (Before)| GCC/LLC (After)
164.gzip/164.gzip       | 0.59            | 0.60
175.vpr/175.vpr         | 0.57            | 0.58
176.gcc/176.gcc         | 0.59            | 0.61
181.mcf/181.mcf         | 0.94            | 0.95
186.crafty/186.crafty   | 0.62            | 0.62
197.parser/197.parser   | 0.89            | 0.88
252.eon/252.eon         | 0.61            | 0.66
253.perlbmk/253.perlbmk | 0.79            | 0.84
254.gap/254.gap         | 0.81            | 0.81
255.vortex/255.vortex   | 0.92            | 0.93
256.bzip2/256.bzip2     | 0.69            | 0.69
300.twolf/300.twolf     | 0.91            | 0.90

llvm-svn: 16147

stored in a binary heap.

llvm-svn: 16143

Move include/Config and include/Support into include/llvm/Config,
include/llvm/ADT and include/llvm/Support. From here on out, all LLVM
public header files must be under include/llvm/.

llvm-svn: 16137

lists. Instead of scanning the vector backwards, scan it forward and
swap each element we want to erase. Then at the end erase all removed
intervals at once. This doesn't save much: 0.08s out of 4s when
compiling 176.gcc.

llvm-svn: 16136

LiveVariables.

llvm-svn: 16076

investicated further as the linearscan variants don't really need
LiveVariables...

llvm-svn: 16074

llvm-svn: 16071

llvm-svn: 15489

llvm-svn: 15200

LiveInterval>. This saves some space and removes the pointer
indirection caused by following the pointer.

llvm-svn: 15167

ownership of the intervals.

llvm-svn: 15155

llvm-svn: 15135

compilation of gcc:

* Use vectors instead of lists for the intervals sets
* Use a heap for the unhandled set to keep intervals always sorted and
  makes insertions back to the heap very fast (compared to scanning a
  list)

llvm-svn: 15103

llvm-svn: 15089

llvm-svn: 15011

llvm-svn: 14991

is sorted.  This is not the case currently, which is causing no end of
problems.

llvm-svn: 14990

llvm-svn: 14626

llvm-svn: 14590

existing llvm::Interval class.

Patch contributed by Vladimir Prus!
http://mail.cs.uiuc.edu/pipermail/llvmbugs/2004-June/000710.html

llvm-svn: 14281

llvm-svn: 13910