RPCS3/llvm-mirror
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-24 11:42:57 +01:00
Code Issues Projects Releases Wiki Activity

rewrite Value::takeName to take advantage of the new symtab stuff. This

Browse Source 
causes it to require no allocations and no symtab lookups in the common
case.  This speeds up instcombine 9.2% on 447.dealII.

llvm-svn: 34324
This commit is contained in:
Chris Lattner 2007-02-15 20:01:43 +00:00
parent 8b185bf778
commit 9084bb5471
1 changed files with 55 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

61
lib/VMCore/Value.cpp
View File

@ -185,15 +185,64 @@ void Value::setName(const char *NameStr, unsigned NameLen) {
/// takeName - transfer the name from V to this value, setting V's name to
/// empty. It is an error to call V->takeName(V).
void Value::takeName(Value *V) {
if (!V->hasName()) {
if (hasName())
setName("");
ValueSymbolTable *ST = 0;
// If this value has a name, drop it.
if (hasName()) {
// Get the symtab this is in.
if (getSymTab(this, ST)) {
// We can't set a name on this value, but we need to clear V's name if
// it has one.
if (V->hasName()) V->setName(0, 0);
return; // Cannot set a name on this value (e.g. constant).
}
// Remove old name.
if (ST)
ST->removeValueName(Name);
Name->Destroy();
Name = 0;
}
// Now we know that this has no name.
// If V has no name either, we're done.
if (!V->hasName()) return;
// Get this's symtab if we didn't before.
if (!ST) {
if (getSymTab(this, ST)) {
// Clear V's name.
V->setName(0, 0);
return; // Cannot set a name on this value (e.g. constant).
}
}
// Get V's ST, this should always succed, because V has a name.
ValueSymbolTable *VST;
bool Failure = getSymTab(V, VST);
assert(!Failure && "V has a name, so it should have a ST!");
// If these values are both in the same symtab, we can do this very fast.
// This works even if both values have no symtab yet.
if (ST == VST) {
// Take the name!
Name = V->Name;
V->Name = 0;
Name->setValue(this);
return;
}
std::string Name = V->getName();
V->setName("");
setName(Name);
// Otherwise, things are slightly more complex. Remove V's name from VST and
// then reinsert it into ST.
if (VST)
VST->removeValueName(V->Name);
Name = V->Name;
V->Name = 0;
Name->setValue(this);
if (ST)
ST->reinsertValue(this);
}