Re-apply 56835 along with header file changes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56848 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index bc66321..4ed456b 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -819,6 +819,7 @@
/// val# of the specified interval is re-materializable.
bool LiveIntervals::isReMaterializable(const LiveInterval &li,
const VNInfo *ValNo, MachineInstr *MI,
+ SmallVectorImpl<LiveInterval*> &SpillIs,
bool &isLoad) {
if (DisableReMat)
return false;
@@ -855,8 +856,8 @@
// If the instruction accesses memory and the memory could be non-constant,
// assume the instruction is not rematerializable.
- for (std::list<MachineMemOperand>::const_iterator I = MI->memoperands_begin(),
- E = MI->memoperands_end(); I != E; ++I) {
+ for (std::list<MachineMemOperand>::const_iterator
+ I = MI->memoperands_begin(), E = MI->memoperands_end(); I != E; ++I){
const MachineMemOperand &MMO = *I;
if (MMO.isVolatile() || MMO.isStore())
return false;
@@ -924,13 +925,21 @@
if (!isValNoAvailableAt(ImpLi, MI, UseIdx))
return false;
}
+
+ // If a register operand of the re-materialized instruction is going to
+ // be spilled next, then it's not legal to re-materialize this instruction.
+ for (unsigned i = 0, e = SpillIs.size(); i != e; ++i)
+ if (ImpUse == SpillIs[i]->reg)
+ return false;
}
return true;
}
/// isReMaterializable - Returns true if every definition of MI of every
/// val# of the specified interval is re-materializable.
-bool LiveIntervals::isReMaterializable(const LiveInterval &li, bool &isLoad) {
+bool LiveIntervals::isReMaterializable(const LiveInterval &li,
+ SmallVectorImpl<LiveInterval*> &SpillIs,
+ bool &isLoad) {
isLoad = false;
for (LiveInterval::const_vni_iterator i = li.vni_begin(), e = li.vni_end();
i != e; ++i) {
@@ -944,7 +953,7 @@
MachineInstr *ReMatDefMI = getInstructionFromIndex(DefIdx);
bool DefIsLoad = false;
if (!ReMatDefMI ||
- !isReMaterializable(li, VNI, ReMatDefMI, DefIsLoad))
+ !isReMaterializable(li, VNI, ReMatDefMI, SpillIs, DefIsLoad))
return false;
isLoad |= DefIsLoad;
}
@@ -1728,6 +1737,7 @@
std::vector<LiveInterval*> LiveIntervals::
addIntervalsForSpills(const LiveInterval &li,
+ SmallVectorImpl<LiveInterval*> &SpillIs,
const MachineLoopInfo *loopInfo, VirtRegMap &vrm,
float &SSWeight) {
@@ -1831,7 +1841,7 @@
MachineInstr *ReMatDefMI = (DefIdx == ~0u)
? 0 : getInstructionFromIndex(DefIdx);
bool dummy;
- if (ReMatDefMI && isReMaterializable(li, VNI, ReMatDefMI, dummy)) {
+ if (ReMatDefMI && isReMaterializable(li, VNI, ReMatDefMI, SpillIs, dummy)) {
// Remember how to remat the def of this val#.
ReMatOrigDefs[VN] = ReMatDefMI;
// Original def may be modified so we have to make a copy here.