6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-12-15 04:30:12 +00:00
Code Issues Projects Releases Wiki Activity

Add a new llcbeta option. This speeds up viterbi from 12.34 to 8.76s on

Browse Source 
X86.  If happy, I'll enable this by default.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31493 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2006-11-07 07:18:40 +00:00
parent 5a4951e936
commit b75a663707
1 changed files with 19 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

23
lib/CodeGen/LiveIntervalAnalysis.cpp
View File

@ -59,6 +59,9 @@ namespace {
EnableJoining("join-liveintervals",
cl::desc("Coallesce copies (default=true)"),
cl::init(true));
static cl::opt<bool>
EnableReweight("enable-majik-f00");
}
void LiveIntervals::getAnalysisUsage(AnalysisUsage &AU) const {
@ -208,14 +211,26 @@ bool LiveIntervals::runOnMachineFunction(MachineFunction &fn) {
}
}
for (iterator I = begin(), E = end(); I != E; ++I) {
LiveInterval &li = I->second;
if (MRegisterInfo::isVirtualRegister(li.reg)) {
LiveInterval &LI = I->second;
if (MRegisterInfo::isVirtualRegister(LI.reg)) {
// If the live interval length 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.
if (isZeroLengthInterval(&li))
li.weight = float(HUGE_VAL);
if (isZeroLengthInterval(&LI))
LI.weight = float(HUGE_VAL);
if (EnableReweight) {
// Divide the weight of the interval by its size. This encourages
// spilling of intervals that are large and have few uses, and
// discourages spilling of small intervals with many uses.
unsigned Size = 0;
for (LiveInterval::iterator II = LI.begin(), E = LI.end(); II != E;++II)
Size += II->end - II->start;
LI.weight /= Size;
}
}
}