Remove AsmThatEarlyClobber etc. from LiveIntervalAnalysis
and redo as linked list walk. Logic moved into RA.
Per review feedback.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56326 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index cb83194..2a23d49 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -674,8 +674,6 @@
/// live interval is an interval [i, j) where 1 <= i <= j < N for
/// which a variable is live
void LiveIntervals::computeIntervals() {
- AsmsThatEarlyClobber.clear();
- AsmsWithEarlyClobberConflict.clear();
DOUT << "********** COMPUTING LIVE INTERVALS **********\n"
<< "********** Function: "
@@ -716,13 +714,15 @@
if (MO.isRegister() && MO.getReg() && MO.isDef()) {
handleRegisterDef(MBB, MI, MIIndex, MO, i);
if (MO.isEarlyClobber()) {
- AsmsThatEarlyClobber.insert(std::make_pair(MO.getReg(), MI));
+ LiveInterval &interval = getOrCreateInterval(MO.getReg());
+ interval.isEarlyClobber = true;
}
}
if (MO.isRegister() && !MO.isDef() &&
MO.getReg() && TargetRegisterInfo::isVirtualRegister(MO.getReg()) &&
MO.overlapsEarlyClobber()) {
- AsmsWithEarlyClobberConflict.insert(std::make_pair(MO.getReg(), MI));
+ LiveInterval &interval = getOrCreateInterval(MO.getReg());
+ interval.overlapsEarlyClobber = true;
}
}
@@ -752,73 +752,6 @@
return ResVal;
}
-/// noEarlyclobberConflict - see whether virtual reg VReg has a conflict with
-/// hard reg HReg because of earlyclobbers.
-///
-/// Earlyclobber operands may not be assigned the same register as
-/// each other, or as earlyclobber-conflict operands (i.e. those that
-/// are non-earlyclobbered inputs to an asm that also has earlyclobbers).
-///
-/// Thus there are two cases to check for:
-/// 1. VReg is an earlyclobber-conflict register and HReg is an earlyclobber
-/// register in some asm that also has VReg as an input.
-/// 2. VReg is an earlyclobber register and HReg is an earlyclobber-conflict
-/// input elsewhere in some asm.
-/// In both cases HReg can be assigned by the user, or assigned early in
-/// register allocation.
-///
-/// Dropping the distinction between earlyclobber and earlyclobber-conflict,
-/// keeping only one multimap, looks promising, but two earlyclobber-conflict
-/// operands may be assigned the same register if they happen to contain the
-/// same value, and that implementation would prevent this.
-///
-bool LiveIntervals::noEarlyclobberConflict(unsigned VReg, VirtRegMap &vrm,
- unsigned HReg) {
- typedef std::multimap<unsigned, MachineInstr*>::iterator It;
-
- // Short circuit the most common case.
- if (AsmsWithEarlyClobberConflict.size()!=0) {
- std::pair<It, It> x = AsmsWithEarlyClobberConflict.equal_range(VReg);
- for (It I = x.first; I!=x.second; I++) {
- MachineInstr* MI = I->second;
- for (int i = MI->getNumOperands() - 1; i >= 0; --i) {
- MachineOperand &MO = MI->getOperand(i);
- if (MO.isRegister() && MO.isEarlyClobber()) {
- unsigned PhysReg = MO.getReg();
- if (PhysReg && TargetRegisterInfo::isVirtualRegister(PhysReg)) {
- if (!vrm.hasPhys(PhysReg))
- continue;
- PhysReg = vrm.getPhys(PhysReg);
- }
- if (PhysReg==HReg)
- return false;
- }
- }
- }
- }
- // Short circuit the most common case.
- if (AsmsThatEarlyClobber.size()!=0) {
- std::pair<It, It> x = AsmsThatEarlyClobber.equal_range(VReg);
- for (It I = x.first; I!=x.second; I++) {
- MachineInstr* MI = I->second;
- for (int i = MI->getNumOperands() - 1; i >= 0; --i) {
- MachineOperand &MO = MI->getOperand(i);
- if (MO.isRegister() && MO.overlapsEarlyClobber()) {
- unsigned PhysReg = MO.getReg();
- if (PhysReg && TargetRegisterInfo::isVirtualRegister(PhysReg)) {
- if (!vrm.hasPhys(PhysReg))
- continue;
- PhysReg = vrm.getPhys(PhysReg);
- }
- if (PhysReg==HReg)
- return false;
- }
- }
- }
- }
- return true;
-}
-
LiveInterval* LiveIntervals::createInterval(unsigned reg) {
float Weight = TargetRegisterInfo::isPhysicalRegister(reg) ?
HUGE_VALF : 0.0F;