6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-07-17 20:29:31 +00:00
Code Issues Projects Releases Wiki Activity

Move some code in the register assignment case that only needs to happen if

Browse Source 
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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22971 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2005-08-22 20:20:42 +00:00
parent 47c0889419
commit a6c1750362
1 changed files with 26 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

43
lib/CodeGen/RegAllocLinearScan.cpp
View File

@ -365,23 +365,11 @@ void RA::assignRegOrStackSlotAtInterval(LiveInterval* cur)
PhysRegTracker backupPrt = *prt_;
std::vector<float> SpillWeights;
SpillWeights.assign(mri_->getNumRegs(), 0.0);
std::vector<std::pair<unsigned, float> > SpillWeightsToAdd;
unsigned StartPosition = cur->beginNumber();
// for each interval in active, update spill weights.
for (IntervalPtrs::const_iterator i = active_.begin(), e = active_.end();
i != e; ++i) {
unsigned reg = i->first->reg;
assert(MRegisterInfo::isVirtualRegister(reg) &&
"Can only allocate virtual registers!");
reg = vrm_->getPhys(reg);
updateSpillWeights(SpillWeights, reg, i->first->weight, mri_);
}
// for every interval in inactive we overlap with, mark the
// register as not free and update spill weights
// register as not free and update spill weights.
for (IntervalPtrs::const_iterator i = inactive_.begin(),
e = inactive_.end(); i != e; ++i) {
if (cur->overlapsFrom(*i->first, i->second-1)) {
@ -390,7 +378,7 @@ void RA::assignRegOrStackSlotAtInterval(LiveInterval* cur)
"Can only allocate virtual registers!");
reg = vrm_->getPhys(reg);
prt_->addRegUse(reg);
updateSpillWeights(SpillWeights, reg, i->first->weight, mri_);
SpillWeightsToAdd.push_back(std::make_pair(reg, i->first->weight));
}
}
@ -407,14 +395,19 @@ void RA::assignRegOrStackSlotAtInterval(LiveInterval* cur)
if (cur->overlapsFrom(*I, II)) {
unsigned reg = I->reg;
prt_->addRegUse(reg);
updateSpillWeights(SpillWeights, reg, I->weight, mri_);
SpillWeightsToAdd.push_back(std::make_pair(reg, I->weight));
}
}
}
// Using the newly updated prt_ object, which includes conflicts in the
// future, see if there are any registers available.
unsigned physReg = getFreePhysReg(cur);
// restore the physical register tracker
// Restore the physical register tracker, removing information about the
// future.
*prt_ = backupPrt;
// if we find a free register, we are done: assign this virtual to
// the free physical register and add this interval to the active
// list.
@ -428,6 +421,22 @@ void RA::assignRegOrStackSlotAtInterval(LiveInterval* cur)
}
DEBUG(std::cerr << "no free registers\n");
// Compile the spill weights into an array that is better for scanning.
std::vector<float> SpillWeights(mri_->getNumRegs(), 0.0);
for (std::vector<std::pair<unsigned, float> >::iterator
I = SpillWeightsToAdd.begin(), E = SpillWeightsToAdd.end(); I != E; ++I)
updateSpillWeights(SpillWeights, I->first, I->second, mri_);
// for each interval in active, update spill weights.
for (IntervalPtrs::const_iterator i = active_.begin(), e = active_.end();
i != e; ++i) {
unsigned reg = i->first->reg;
assert(MRegisterInfo::isVirtualRegister(reg) &&
"Can only allocate virtual registers!");
reg = vrm_->getPhys(reg);
updateSpillWeights(SpillWeights, reg, i->first->weight, mri_);
}
DEBUG(std::cerr << "\tassigning stack slot at interval "<< *cur << ":\n");
float minWeight = float(HUGE_VAL);