Extract helper function to merge MemoryOperand lists [NFC]
In the discussion on http://reviews.llvm.org/D15730, Andy pointed out we had a utility function for merging MMO lists. Since it turned we actually had two copies and there's another review in progress (http://reviews.llvm.org/D15230) which needs the same, extract it into a utility function and clean up the interfaces to make it easier to use with a MachineInstBuilder.
I introduced a pair here to track size and allocation together. I think we should probably move in the direction of the MachineOperandsRef helper class, but I'm leaving that for further work. I want to get the poison state introduced before I make major changes to the interface.
Differential Revision: http://reviews.llvm.org/D15757
llvm-svn: 256909
diff --git a/llvm/include/llvm/CodeGen/MachineInstr.h b/llvm/include/llvm/CodeGen/MachineInstr.h
index 666ecc1..05c9a9e 100644
--- a/llvm/include/llvm/CodeGen/MachineInstr.h
+++ b/llvm/include/llvm/CodeGen/MachineInstr.h
@@ -1180,11 +1180,26 @@
/// Assign this MachineInstr's memory reference descriptor list.
/// This does not transfer ownership.
void setMemRefs(mmo_iterator NewMemRefs, mmo_iterator NewMemRefsEnd) {
- MemRefs = NewMemRefs;
- NumMemRefs = uint8_t(NewMemRefsEnd - NewMemRefs);
- assert(NumMemRefs == NewMemRefsEnd - NewMemRefs && "Too many memrefs");
+ setMemRefs(std::make_pair(NewMemRefs, NewMemRefsEnd-NewMemRefs));
}
+ /// Assign this MachineInstr's memory reference descriptor list. First
+ /// element in the pair is the begin iterator/pointer to the array; the
+ /// second is the number of MemoryOperands. This does not transfer ownership
+ /// of the underlying memory.
+ void setMemRefs(std::pair<mmo_iterator, unsigned> NewMemRefs) {
+ MemRefs = NewMemRefs.first;
+ NumMemRefs = uint8_t(NewMemRefs.second);
+ assert(NumMemRefs == NewMemRefs.second &&
+ "Too many memrefs - must drop memory operands");
+ }
+
+ /// Return a set of memrefs (begin iterator, size) which conservatively
+ /// describe the memory behavior of both MachineInstrs. This is appropriate
+ /// for use when merging two MachineInstrs into one. This routine does not
+ /// modify the memrefs of the this MachineInstr.
+ std::pair<mmo_iterator, unsigned> mergeMemRefsWith(const MachineInstr& Other);
+
/// Clear this MachineInstr's memory reference descriptor list. This resets
/// the memrefs to their most conservative state. This should be used only
/// as a last resort since it greatly pessimizes our knowledge of the memory
diff --git a/llvm/include/llvm/CodeGen/MachineInstrBuilder.h b/llvm/include/llvm/CodeGen/MachineInstrBuilder.h
index aa5f4b2..8fe9b28 100644
--- a/llvm/include/llvm/CodeGen/MachineInstrBuilder.h
+++ b/llvm/include/llvm/CodeGen/MachineInstrBuilder.h
@@ -162,6 +162,11 @@
return *this;
}
+ const MachineInstrBuilder &setMemRefs(std::pair<MachineInstr::mmo_iterator,
+ unsigned> MemOperandsRef) const {
+ MI->setMemRefs(MemOperandsRef);
+ return *this;
+ }
const MachineInstrBuilder &addOperand(const MachineOperand &MO) const {
MI->addOperand(*MF, MO);
diff --git a/llvm/lib/CodeGen/MachineInstr.cpp b/llvm/lib/CodeGen/MachineInstr.cpp
index 2ace4bc..5188b84 100644
--- a/llvm/lib/CodeGen/MachineInstr.cpp
+++ b/llvm/lib/CodeGen/MachineInstr.cpp
@@ -866,6 +866,26 @@
setMemRefs(NewMemRefs, NewMemRefs + NewNum);
}
+std::pair<MachineInstr::mmo_iterator, unsigned>
+MachineInstr::mergeMemRefsWith(const MachineInstr& Other) {
+ // TODO: If we end up with too many memory operands, return the empty
+ // conservative set rather than failing asserts.
+ // TODO: consider uniquing elements within the operand lists to reduce
+ // space usage and fall back to conservative information less often.
+ size_t CombinedNumMemRefs = (memoperands_end() - memoperands_begin())
+ + (Other.memoperands_end() - Other.memoperands_begin());
+
+ MachineFunction *MF = getParent()->getParent();
+ mmo_iterator MemBegin = MF->allocateMemRefsArray(CombinedNumMemRefs);
+ mmo_iterator MemEnd = std::copy(memoperands_begin(), memoperands_end(),
+ MemBegin);
+ MemEnd = std::copy(Other.memoperands_begin(), Other.memoperands_end(),
+ MemEnd);
+ assert(MemEnd - MemBegin == CombinedNumMemRefs && "missing memrefs");
+
+ return std::make_pair(MemBegin, CombinedNumMemRefs);
+}
+
bool MachineInstr::hasPropertyInBundle(unsigned Mask, QueryType Type) const {
assert(!isBundledWithPred() && "Must be called on bundle header");
for (MachineBasicBlock::const_instr_iterator MII = getIterator();; ++MII) {
diff --git a/llvm/lib/Target/AArch64/AArch64LoadStoreOptimizer.cpp b/llvm/lib/Target/AArch64/AArch64LoadStoreOptimizer.cpp
index 566aa2c..43664df 100644
--- a/llvm/lib/Target/AArch64/AArch64LoadStoreOptimizer.cpp
+++ b/llvm/lib/Target/AArch64/AArch64LoadStoreOptimizer.cpp
@@ -613,21 +613,6 @@
(UnscaledLdOffset + LoadSize <= (UnscaledStOffset + StoreSize));
}
-// Copy MachineMemOperands from Op0 and Op1 to a new array assigned to MI.
-static void concatenateMemOperands(MachineInstr *MI, MachineInstr *Op0,
- MachineInstr *Op1) {
- assert(MI->memoperands_empty() && "expected a new machineinstr");
- size_t numMemRefs = (Op0->memoperands_end() - Op0->memoperands_begin()) +
- (Op1->memoperands_end() - Op1->memoperands_begin());
-
- MachineFunction *MF = MI->getParent()->getParent();
- MachineSDNode::mmo_iterator MemBegin = MF->allocateMemRefsArray(numMemRefs);
- MachineSDNode::mmo_iterator MemEnd =
- std::copy(Op0->memoperands_begin(), Op0->memoperands_end(), MemBegin);
- MemEnd = std::copy(Op1->memoperands_begin(), Op1->memoperands_end(), MemEnd);
- MI->setMemRefs(MemBegin, MemEnd);
-}
-
MachineBasicBlock::iterator
AArch64LoadStoreOpt::mergePairedInsns(MachineBasicBlock::iterator I,
MachineBasicBlock::iterator Paired,
@@ -692,10 +677,8 @@
TII->get(NewOpc))
.addOperand(getLdStRegOp(RtNewDest))
.addOperand(BaseRegOp)
- .addImm(OffsetImm);
-
- // Copy MachineMemOperands from the original loads.
- concatenateMemOperands(NewMemMI, I, Paired);
+ .addImm(OffsetImm)
+ .setMemRefs(I->mergeMemRefsWith(*Paired));
DEBUG(
dbgs()
@@ -786,9 +769,8 @@
TII->get(NewOpc))
.addOperand(getLdStRegOp(I))
.addOperand(BaseRegOp)
- .addImm(OffsetImm);
- // Copy MachineMemOperands from the original stores.
- concatenateMemOperands(MIB, I, Paired);
+ .addImm(OffsetImm)
+ .setMemRefs(I->mergeMemRefsWith(*Paired));
} else {
// Handle Unscaled
if (IsUnscaled)
diff --git a/llvm/lib/Target/ARM/ARMLoadStoreOptimizer.cpp b/llvm/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
index 725b838..6e7e47b 100644
--- a/llvm/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
+++ b/llvm/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
@@ -1986,23 +1986,6 @@
return AddedRegPressure.size() <= MemRegs.size() * 2;
}
-
-/// Copy \p Op0 and \p Op1 operands into a new array assigned to MI.
-static void concatenateMemOperands(MachineInstr *MI, MachineInstr *Op0,
- MachineInstr *Op1) {
- assert(MI->memoperands_empty() && "expected a new machineinstr");
- size_t numMemRefs = (Op0->memoperands_end() - Op0->memoperands_begin())
- + (Op1->memoperands_end() - Op1->memoperands_begin());
-
- MachineFunction *MF = MI->getParent()->getParent();
- MachineSDNode::mmo_iterator MemBegin = MF->allocateMemRefsArray(numMemRefs);
- MachineSDNode::mmo_iterator MemEnd =
- std::copy(Op0->memoperands_begin(), Op0->memoperands_end(), MemBegin);
- MemEnd =
- std::copy(Op1->memoperands_begin(), Op1->memoperands_end(), MemEnd);
- MI->setMemRefs(MemBegin, MemEnd);
-}
-
bool
ARMPreAllocLoadStoreOpt::CanFormLdStDWord(MachineInstr *Op0, MachineInstr *Op1,
DebugLoc &dl, unsigned &NewOpc,
@@ -2196,7 +2179,7 @@
if (!isT2)
MIB.addReg(0);
MIB.addImm(Offset).addImm(Pred).addReg(PredReg);
- concatenateMemOperands(MIB, Op0, Op1);
+ MIB.setMemRefs(Op0->mergeMemRefsWith(*Op1));
DEBUG(dbgs() << "Formed " << *MIB << "\n");
++NumLDRDFormed;
} else {
@@ -2210,7 +2193,7 @@
if (!isT2)
MIB.addReg(0);
MIB.addImm(Offset).addImm(Pred).addReg(PredReg);
- concatenateMemOperands(MIB, Op0, Op1);
+ MIB.setMemRefs(Op0->mergeMemRefsWith(*Op1));
DEBUG(dbgs() << "Formed " << *MIB << "\n");
++NumSTRDFormed;
}