Add the long awaited memory operand folding support for linear scan
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12058 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index fc46de2..d6cc357 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -31,6 +31,7 @@
#include "Support/Debug.h"
#include "Support/Statistic.h"
#include "Support/STLExtras.h"
+#include "VirtRegMap.h"
#include <cmath>
#include <iostream>
#include <limits>
@@ -184,7 +185,9 @@
return true;
}
-void LiveIntervals::updateSpilledInterval(Interval& li, int slot)
+void LiveIntervals::updateSpilledInterval(Interval& li,
+ VirtRegMap& vrm,
+ int slot)
{
assert(li.weight != std::numeric_limits<float>::infinity() &&
"attempt to spill already spilled interval!");
@@ -202,27 +205,40 @@
while (!getInstructionFromIndex(index)) index += InstrSlots::NUM;
MachineBasicBlock::iterator mi = getInstructionFromIndex(index);
+ for_operand:
for (unsigned i = 0; i < mi->getNumOperands(); ++i) {
MachineOperand& mop = mi->getOperand(i);
if (mop.isRegister() && mop.getReg() == li.reg) {
- // This is tricky. We need to add information in
- // the interval about the spill code so we have to
- // use our extra load/store slots.
- //
- // If we have a use we are going to have a load so
- // we start the interval from the load slot
- // onwards. Otherwise we start from the def slot.
- unsigned start = (mop.isUse() ?
- getLoadIndex(index) :
- getDefIndex(index));
- // If we have a def we are going to have a store
- // right after it so we end the interval after the
- // use of the next instruction. Otherwise we end
- // after the use of this instruction.
- unsigned end = 1 + (mop.isDef() ?
- getUseIndex(index+InstrSlots::NUM) :
- getUseIndex(index));
- li.addRange(start, end);
+ MachineInstr* old = mi;
+ if (mri_->foldMemoryOperand(mi, i, slot)) {
+ lv_->instructionChanged(old, mi);
+ vrm.virtFolded(li.reg, old, mi);
+ mi2iMap_.erase(old);
+ i2miMap_[index/InstrSlots::NUM] = mi;
+ mi2iMap_[mi] = index;
+ ++numFolded;
+ goto for_operand;
+ }
+ else {
+ // This is tricky. We need to add information in
+ // the interval about the spill code so we have to
+ // use our extra load/store slots.
+ //
+ // If we have a use we are going to have a load so
+ // we start the interval from the load slot
+ // onwards. Otherwise we start from the def slot.
+ unsigned start = (mop.isUse() ?
+ getLoadIndex(index) :
+ getDefIndex(index));
+ // If we have a def we are going to have a store
+ // right after it so we end the interval after the
+ // use of the next instruction. Otherwise we end
+ // after the use of this instruction.
+ unsigned end = 1 + (mop.isDef() ?
+ getUseIndex(index+InstrSlots::NUM) :
+ getUseIndex(index));
+ li.addRange(start, end);
+ }
}
}
}