Refactor UpdatePredRedefs and StepForward to avoid duplication. NFC
Note, this is a reapplication of r236515 with a fix to not assert on non-register operands, but instead only handle them until the subsequent commit. Original commit message follows.
The code was basically the same here already. Just added an out parameter for a vector of seen defs so that UpdatePredRedefs can call StepForward first, then do its own post processing on the seen defs.
Will be used in the next commit to also handle regmasks.
llvm-svn: 236538
diff --git a/llvm/lib/CodeGen/LivePhysRegs.cpp b/llvm/lib/CodeGen/LivePhysRegs.cpp
index 89567ef..b636927 100644
--- a/llvm/lib/CodeGen/LivePhysRegs.cpp
+++ b/llvm/lib/CodeGen/LivePhysRegs.cpp
@@ -22,12 +22,17 @@
/// \brief Remove all registers from the set that get clobbered by the register
/// mask.
-void LivePhysRegs::removeRegsInMask(const MachineOperand &MO) {
+/// The clobbers set will be the list of live registers clobbered
+/// by the regmask.
+void LivePhysRegs::removeRegsInMask(const MachineOperand &MO,
+ SmallVectorImpl<std::pair<unsigned, const MachineOperand*>> *Clobbers) {
SparseSet<unsigned>::iterator LRI = LiveRegs.begin();
while (LRI != LiveRegs.end()) {
- if (MO.clobbersPhysReg(*LRI))
+ if (MO.clobbersPhysReg(*LRI)) {
+ if (Clobbers)
+ Clobbers->push_back(std::make_pair(*LRI, &MO));
LRI = LiveRegs.erase(LRI);
- else
+ } else
++LRI;
}
}
@@ -45,7 +50,7 @@
continue;
removeReg(Reg);
} else if (O->isRegMask())
- removeRegsInMask(*O);
+ removeRegsInMask(*O, nullptr);
}
// Add uses to the set.
@@ -63,8 +68,8 @@
/// killed-uses, add defs. This is the not recommended way, because it depends
/// on accurate kill flags. If possible use stepBackwards() instead of this
/// function.
-void LivePhysRegs::stepForward(const MachineInstr &MI) {
- SmallVector<unsigned, 4> Defs;
+void LivePhysRegs::stepForward(const MachineInstr &MI,
+ SmallVectorImpl<std::pair<unsigned, const MachineOperand*>> &Clobbers) {
// Remove killed registers from the set.
for (ConstMIBundleOperands O(&MI); O.isValid(); ++O) {
if (O->isReg()) {
@@ -73,7 +78,7 @@
continue;
if (O->isDef()) {
if (!O->isDead())
- Defs.push_back(Reg);
+ Clobbers.push_back(std::make_pair(Reg, &*O));
} else {
if (!O->isKill())
continue;
@@ -81,12 +86,12 @@
removeReg(Reg);
}
} else if (O->isRegMask())
- removeRegsInMask(*O);
+ removeRegsInMask(*O, &Clobbers);
}
// Add defs to the set.
- for (unsigned i = 0, e = Defs.size(); i != e; ++i)
- addReg(Defs[i]);
+ for (auto Reg : Clobbers)
+ addReg(Reg.first);
}
/// Prin the currently live registers to OS.