6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-09-30 19:55:11 +00:00
Code Issues Projects Releases Wiki Activity

Teach ConnectedVNInfoEqClasses::Classify to deal with unused values.

Browse Source 
We don't want unused values forming their own equivalence classes, so we lump
them all together in one class, and then merge them with the class of the last
used value.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117670 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jakob Stoklund Olesen 2010-10-29 17:37:29 +00:00
parent c94fcb1507
commit 6d309059a7
1 changed files with 15 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
lib/CodeGen/LiveInterval.cpp
View File

@ -740,11 +740,20 @@ unsigned ConnectedVNInfoEqClasses::Classify(const LiveInterval *LI) {
for (unsigned i = 0, e = LI->getNumValNums(); i != e; ++i)
eqClass_.push_back(i);
const VNInfo *used = 0, *unused = 0;
// Determine connections.
for (LiveInterval::const_vni_iterator I = LI->vni_begin(), E = LI->vni_end();
I != E; ++I) {
const VNInfo *VNI = *I;
assert(!VNI->isUnused() && "Cannot handle unused values");
// Group all unused values into one class.
if (VNI->isUnused()) {
if (unused)
Connect(unused->id, VNI->id);
unused = VNI;
continue;
}
used = VNI;
if (VNI->isPHIDef()) {
const MachineBasicBlock *MBB = lis_.getMBBFromIndex(VNI->def);
assert(MBB && "Phi-def has no defining MBB");
@ -762,6 +771,11 @@ unsigned ConnectedVNInfoEqClasses::Classify(const LiveInterval *LI) {
Connect(VNI->id, UVNI->id);
}
}
// Lump all the unused values in with the last used value.
if (used && unused)
Connect(used->id, unused->id);
return Renumber();
}