#define DEBUG_TYPE "dagcombine"
#include "llvm/CodeGen/SelectionDAG.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetFrameInfo.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
bool NotExtCompare = false);
SDOperand SimplifySetCC(MVT::ValueType VT, SDOperand N0, SDOperand N1,
ISD::CondCode Cond, bool foldBooleans = true);
- bool SimplifyNodeWithTwoResults(SDNode *N, unsigned LoOp, unsigned HiOp);
+ SDOperand SimplifyNodeWithTwoResults(SDNode *N, unsigned LoOp,
+ unsigned HiOp);
SDOperand ConstantFoldBIT_CONVERTofBUILD_VECTOR(SDNode *, MVT::ValueType);
SDOperand BuildSDIV(SDNode *N);
SDOperand BuildUDIV(SDNode *N);
SDOperand RV = combine(N);
- if (RV.Val) {
- ++NodesCombined;
- // If we get back the same node we passed in, rather than a new node or
- // zero, we know that the node must have defined multiple values and
- // CombineTo was used. Since CombineTo takes care of the worklist
- // mechanics for us, we have no work to do in this case.
- if (RV.Val != N) {
- assert(N->getOpcode() != ISD::DELETED_NODE &&
- RV.Val->getOpcode() != ISD::DELETED_NODE &&
- "Node was deleted but visit returned new node!");
-
- DOUT << "\nReplacing.3 "; DEBUG(N->dump(&DAG));
- DOUT << "\nWith: "; DEBUG(RV.Val->dump(&DAG));
- DOUT << '\n';
- std::vector<SDNode*> NowDead;
- if (N->getNumValues() == RV.Val->getNumValues())
- DAG.ReplaceAllUsesWith(N, RV.Val, &NowDead);
- else {
- assert(N->getValueType(0) == RV.getValueType() && "Type mismatch");
- SDOperand OpV = RV;
- DAG.ReplaceAllUsesWith(N, &OpV, &NowDead);
- }
-
- // Push the new node and any users onto the worklist
- AddToWorkList(RV.Val);
- AddUsersToWorkList(RV.Val);
-
- // Nodes can be reintroduced into the worklist. Make sure we do not
- // process a node that has been replaced.
- removeFromWorkList(N);
- for (unsigned i = 0, e = NowDead.size(); i != e; ++i)
- removeFromWorkList(NowDead[i]);
-
- // Finally, since the node is now dead, remove it from the graph.
- DAG.DeleteNode(N);
- }
+ if (RV.Val == 0)
+ continue;
+
+ ++NodesCombined;
+
+ // If we get back the same node we passed in, rather than a new node or
+ // zero, we know that the node must have defined multiple values and
+ // CombineTo was used. Since CombineTo takes care of the worklist
+ // mechanics for us, we have no work to do in this case.
+ if (RV.Val == N)
+ continue;
+
+ assert(N->getOpcode() != ISD::DELETED_NODE &&
+ RV.Val->getOpcode() != ISD::DELETED_NODE &&
+ "Node was deleted but visit returned new node!");
+
+ DOUT << "\nReplacing.3 "; DEBUG(N->dump(&DAG));
+ DOUT << "\nWith: "; DEBUG(RV.Val->dump(&DAG));
+ DOUT << '\n';
+ std::vector<SDNode*> NowDead;
+ if (N->getNumValues() == RV.Val->getNumValues())
+ DAG.ReplaceAllUsesWith(N, RV.Val, &NowDead);
+ else {
+ assert(N->getValueType(0) == RV.getValueType() &&
+ N->getNumValues() == 1 && "Type mismatch");
+ SDOperand OpV = RV;
+ DAG.ReplaceAllUsesWith(N, &OpV, &NowDead);
}
+
+ // Push the new node and any users onto the worklist
+ AddToWorkList(RV.Val);
+ AddUsersToWorkList(RV.Val);
+
+ // Add any uses of the old node to the worklist in case this node is the
+ // last one that uses them. They may become dead after this node is
+ // deleted.
+ for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
+ AddToWorkList(N->getOperand(i).Val);
+
+ // Nodes can be reintroduced into the worklist. Make sure we do not
+ // process a node that has been replaced.
+ removeFromWorkList(N);
+ for (unsigned i = 0, e = NowDead.size(); i != e; ++i)
+ removeFromWorkList(NowDead[i]);
+
+ // Finally, since the node is now dead, remove it from the graph.
+ DAG.DeleteNode(N);
}
// If the root changed (e.g. it was a dead load, update the root).
// If we've change things around then replace token factor.
if (Changed) {
- if (Ops.size() == 0) {
+ if (Ops.empty()) {
// The entry token is the only possible outcome.
Result = DAG.getEntryNode();
} else {
return DAG.getNode(ISD::SUB, VT, DAG.getConstant(0, VT), N0);
// If we know the sign bits of both operands are zero, strength reduce to a
// udiv instead. Handles (X&15) /s 4 -> X&15 >> 2
- uint64_t SignBit = 1ULL << (MVT::getSizeInBits(VT)-1);
- if (DAG.MaskedValueIsZero(N1, SignBit) &&
- DAG.MaskedValueIsZero(N0, SignBit))
- return DAG.getNode(ISD::UDIV, N1.getValueType(), N0, N1);
+ if (!MVT::isVector(VT)) {
+ uint64_t SignBit = MVT::getIntVTSignBit(VT);
+ if (DAG.MaskedValueIsZero(N1, SignBit) &&
+ DAG.MaskedValueIsZero(N0, SignBit))
+ return DAG.getNode(ISD::UDIV, N1.getValueType(), N0, N1);
+ }
// fold (sdiv X, pow2) -> simple ops after legalize
if (N1C && N1C->getValue() && !TLI.isIntDivCheap() &&
(isPowerOf2_64(N1C->getSignExtended()) ||
return DAG.getNode(ISD::SREM, VT, N0, N1);
// If we know the sign bits of both operands are zero, strength reduce to a
// urem instead. Handles (X & 0x0FFFFFFF) %s 16 -> X&15
- uint64_t SignBit = 1ULL << (MVT::getSizeInBits(VT)-1);
- if (DAG.MaskedValueIsZero(N1, SignBit) &&
- DAG.MaskedValueIsZero(N0, SignBit))
- return DAG.getNode(ISD::UREM, VT, N0, N1);
+ if (!MVT::isVector(VT)) {
+ uint64_t SignBit = MVT::getIntVTSignBit(VT);
+ if (DAG.MaskedValueIsZero(N1, SignBit) &&
+ DAG.MaskedValueIsZero(N0, SignBit))
+ return DAG.getNode(ISD::UREM, VT, N0, N1);
+ }
// If X/C can be simplified by the division-by-constant logic, lower
// X%C to the equivalent of X-X/C*C.
if (N1C && !N1C->isNullValue()) {
SDOperand Div = DAG.getNode(ISD::SDIV, VT, N0, N1);
+ AddToWorkList(Div.Val);
SDOperand OptimizedDiv = combine(Div.Val);
if (OptimizedDiv.Val && OptimizedDiv.Val != Div.Val) {
SDOperand Mul = DAG.getNode(ISD::MUL, VT, OptimizedDiv, N1);
/// compute two values. LoOp and HiOp give the opcodes for the two computations
/// that are being performed. Return true if a simplification was made.
///
-bool DAGCombiner::SimplifyNodeWithTwoResults(SDNode *N,
- unsigned LoOp, unsigned HiOp) {
+SDOperand DAGCombiner::SimplifyNodeWithTwoResults(SDNode *N, unsigned LoOp,
+ unsigned HiOp) {
// If the high half is not needed, just compute the low half.
bool HiExists = N->hasAnyUseOfValue(1);
if (!HiExists &&
(!AfterLegalize ||
TLI.isOperationLegal(LoOp, N->getValueType(0)))) {
- DAG.ReplaceAllUsesOfValueWith(SDOperand(N, 0),
- DAG.getNode(LoOp, N->getValueType(0),
- N->op_begin(),
- N->getNumOperands()));
- return true;
+ SDOperand Res = DAG.getNode(LoOp, N->getValueType(0), N->op_begin(),
+ N->getNumOperands());
+ return CombineTo(N, Res, Res);
}
// If the low half is not needed, just compute the high half.
if (!LoExists &&
(!AfterLegalize ||
TLI.isOperationLegal(HiOp, N->getValueType(1)))) {
- DAG.ReplaceAllUsesOfValueWith(SDOperand(N, 1),
- DAG.getNode(HiOp, N->getValueType(1),
- N->op_begin(),
- N->getNumOperands()));
- return true;
+ SDOperand Res = DAG.getNode(HiOp, N->getValueType(1), N->op_begin(),
+ N->getNumOperands());
+ return CombineTo(N, Res, Res);
}
// If both halves are used, return as it is.
if (LoExists && HiExists)
- return false;
+ return SDOperand();
// If the two computed results can be simplified separately, separate them.
- bool RetVal = false;
if (LoExists) {
SDOperand Lo = DAG.getNode(LoOp, N->getValueType(0),
N->op_begin(), N->getNumOperands());
+ AddToWorkList(Lo.Val);
SDOperand LoOpt = combine(Lo.Val);
- if (LoOpt.Val && LoOpt != Lo &&
- TLI.isOperationLegal(LoOpt.getOpcode(), LoOpt.getValueType())) {
- RetVal = true;
- DAG.ReplaceAllUsesOfValueWith(SDOperand(N, 0), LoOpt);
- } else
- DAG.DeleteNode(Lo.Val);
+ if (LoOpt.Val && LoOpt.Val != Lo.Val &&
+ TLI.isOperationLegal(LoOpt.getOpcode(), LoOpt.getValueType()))
+ return CombineTo(N, LoOpt, LoOpt);
}
if (HiExists) {
SDOperand Hi = DAG.getNode(HiOp, N->getValueType(1),
N->op_begin(), N->getNumOperands());
+ AddToWorkList(Hi.Val);
SDOperand HiOpt = combine(Hi.Val);
if (HiOpt.Val && HiOpt != Hi &&
- TLI.isOperationLegal(HiOpt.getOpcode(), HiOpt.getValueType())) {
- RetVal = true;
- DAG.ReplaceAllUsesOfValueWith(SDOperand(N, 1), HiOpt);
- } else
- DAG.DeleteNode(Hi.Val);
+ TLI.isOperationLegal(HiOpt.getOpcode(), HiOpt.getValueType()))
+ return CombineTo(N, HiOpt, HiOpt);
}
-
- return RetVal;
+ return SDOperand();
}
SDOperand DAGCombiner::visitSMUL_LOHI(SDNode *N) {
-
- if (SimplifyNodeWithTwoResults(N, ISD::MUL, ISD::MULHS))
- return SDOperand();
+ SDOperand Res = SimplifyNodeWithTwoResults(N, ISD::MUL, ISD::MULHS);
+ if (Res.Val) return Res;
return SDOperand();
}
SDOperand DAGCombiner::visitUMUL_LOHI(SDNode *N) {
-
- if (SimplifyNodeWithTwoResults(N, ISD::MUL, ISD::MULHU))
- return SDOperand();
+ SDOperand Res = SimplifyNodeWithTwoResults(N, ISD::MUL, ISD::MULHU);
+ if (Res.Val) return Res;
return SDOperand();
}
SDOperand DAGCombiner::visitSDIVREM(SDNode *N) {
-
- if (SimplifyNodeWithTwoResults(N, ISD::SDIV, ISD::SREM))
- return SDOperand();
+ SDOperand Res = SimplifyNodeWithTwoResults(N, ISD::SDIV, ISD::SREM);
+ if (Res.Val) return Res;
return SDOperand();
}
SDOperand DAGCombiner::visitUDIVREM(SDNode *N) {
-
- if (SimplifyNodeWithTwoResults(N, ISD::UDIV, ISD::UREM))
- return SDOperand();
+ SDOperand Res = SimplifyNodeWithTwoResults(N, ISD::UDIV, ISD::UREM);
+ if (Res.Val) return Res;
return SDOperand();
}
// fold (zext_inreg (extload x)) -> (zextload x)
if (ISD::isEXTLoad(N0.Val) && ISD::isUNINDEXEDLoad(N0.Val)) {
LoadSDNode *LN0 = cast<LoadSDNode>(N0);
- MVT::ValueType EVT = LN0->getLoadedVT();
+ MVT::ValueType EVT = LN0->getMemoryVT();
// If we zero all the possible extended bits, then we can turn this into
// a zextload if we are running before legalize or the operation is legal.
if (DAG.MaskedValueIsZero(N1, ~0ULL << MVT::getSizeInBits(EVT)) &&
if (ISD::isSEXTLoad(N0.Val) && ISD::isUNINDEXEDLoad(N0.Val) &&
N0.hasOneUse()) {
LoadSDNode *LN0 = cast<LoadSDNode>(N0);
- MVT::ValueType EVT = LN0->getLoadedVT();
+ MVT::ValueType EVT = LN0->getMemoryVT();
// If we zero all the possible extended bits, then we can turn this into
// a zextload if we are running before legalize or the operation is legal.
if (DAG.MaskedValueIsZero(N1, ~0ULL << MVT::getSizeInBits(EVT)) &&
else
EVT = MVT::Other;
- LoadedVT = LN0->getLoadedVT();
+ LoadedVT = LN0->getMemoryVT();
if (EVT != MVT::Other && LoadedVT > EVT &&
(!AfterLegalize || TLI.isLoadXLegal(ISD::ZEXTLOAD, EVT))) {
MVT::ValueType PtrType = N0.getOperand(1).getValueType();
if ((ISD::isSEXTLoad(N0.Val) || ISD::isEXTLoad(N0.Val)) &&
ISD::isUNINDEXEDLoad(N0.Val) && N0.hasOneUse()) {
LoadSDNode *LN0 = cast<LoadSDNode>(N0);
- MVT::ValueType EVT = LN0->getLoadedVT();
+ MVT::ValueType EVT = LN0->getMemoryVT();
if (!AfterLegalize || TLI.isLoadXLegal(ISD::SEXTLOAD, EVT)) {
SDOperand ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, VT, LN0->getChain(),
LN0->getBasePtr(), LN0->getSrcValue(),
if ((ISD::isZEXTLoad(N0.Val) || ISD::isEXTLoad(N0.Val)) &&
ISD::isUNINDEXEDLoad(N0.Val) && N0.hasOneUse()) {
LoadSDNode *LN0 = cast<LoadSDNode>(N0);
- MVT::ValueType EVT = LN0->getLoadedVT();
+ MVT::ValueType EVT = LN0->getMemoryVT();
SDOperand ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, VT, LN0->getChain(),
LN0->getBasePtr(), LN0->getSrcValue(),
LN0->getSrcValueOffset(), EVT,
!ISD::isNON_EXTLoad(N0.Val) && ISD::isUNINDEXEDLoad(N0.Val) &&
N0.hasOneUse()) {
LoadSDNode *LN0 = cast<LoadSDNode>(N0);
- MVT::ValueType EVT = LN0->getLoadedVT();
+ MVT::ValueType EVT = LN0->getMemoryVT();
SDOperand ExtLoad = DAG.getExtLoad(LN0->getExtensionType(), VT,
LN0->getChain(), LN0->getBasePtr(),
LN0->getSrcValue(),
// fold (sext_inreg (extload x)) -> (sextload x)
if (ISD::isEXTLoad(N0.Val) &&
ISD::isUNINDEXEDLoad(N0.Val) &&
- EVT == cast<LoadSDNode>(N0)->getLoadedVT() &&
+ EVT == cast<LoadSDNode>(N0)->getMemoryVT() &&
(!AfterLegalize || TLI.isLoadXLegal(ISD::SEXTLOAD, EVT))) {
LoadSDNode *LN0 = cast<LoadSDNode>(N0);
SDOperand ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, VT, LN0->getChain(),
// fold (sext_inreg (zextload x)) -> (sextload x) iff load has one use
if (ISD::isZEXTLoad(N0.Val) && ISD::isUNINDEXEDLoad(N0.Val) &&
N0.hasOneUse() &&
- EVT == cast<LoadSDNode>(N0)->getLoadedVT() &&
+ EVT == cast<LoadSDNode>(N0)->getMemoryVT() &&
(!AfterLegalize || TLI.isLoadXLegal(ISD::SEXTLOAD, EVT))) {
LoadSDNode *LN0 = cast<LoadSDNode>(N0);
SDOperand ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, VT, LN0->getChain(),
}
}
+ // Fold bitconvert(fneg(x)) -> xor(bitconvert(x), signbit)
+ // Fold bitconvert(fabs(x)) -> and(bitconvert(x), ~signbit)
+ // This often reduces constant pool loads.
+ if ((N0.getOpcode() == ISD::FNEG || N0.getOpcode() == ISD::FABS) &&
+ N0.Val->hasOneUse() && MVT::isInteger(VT) && !MVT::isVector(VT)) {
+ SDOperand NewConv = DAG.getNode(ISD::BIT_CONVERT, VT, N0.getOperand(0));
+ AddToWorkList(NewConv.Val);
+
+ uint64_t SignBit = MVT::getIntVTSignBit(VT);
+ if (N0.getOpcode() == ISD::FNEG)
+ return DAG.getNode(ISD::XOR, VT, NewConv, DAG.getConstant(SignBit, VT));
+ assert(N0.getOpcode() == ISD::FABS);
+ return DAG.getNode(ISD::AND, VT, NewConv, DAG.getConstant(~SignBit, VT));
+ }
+
+ // Fold bitconvert(fcopysign(cst, x)) -> bitconvert(x)&sign | cst&~sign'
+ // Note that we don't handle copysign(x,cst) because this can always be folded
+ // to an fneg or fabs.
+ if (N0.getOpcode() == ISD::FCOPYSIGN && N0.Val->hasOneUse() &&
+ isa<ConstantFPSDNode>(N0.getOperand(0)) &&
+ MVT::isInteger(VT) && !MVT::isVector(VT)) {
+ unsigned OrigXWidth = MVT::getSizeInBits(N0.getOperand(1).getValueType());
+ SDOperand X = DAG.getNode(ISD::BIT_CONVERT, MVT::getIntegerType(OrigXWidth),
+ N0.getOperand(1));
+ AddToWorkList(X.Val);
+
+ // If X has a different width than the result/lhs, sext it or truncate it.
+ unsigned VTWidth = MVT::getSizeInBits(VT);
+ if (OrigXWidth < VTWidth) {
+ X = DAG.getNode(ISD::SIGN_EXTEND, VT, X);
+ AddToWorkList(X.Val);
+ } else if (OrigXWidth > VTWidth) {
+ // To get the sign bit in the right place, we have to shift it right
+ // before truncating.
+ X = DAG.getNode(ISD::SRL, X.getValueType(), X,
+ DAG.getConstant(OrigXWidth-VTWidth, X.getValueType()));
+ AddToWorkList(X.Val);
+ X = DAG.getNode(ISD::TRUNCATE, VT, X);
+ AddToWorkList(X.Val);
+ }
+
+ uint64_t SignBit = MVT::getIntVTSignBit(VT);
+ X = DAG.getNode(ISD::AND, VT, X, DAG.getConstant(SignBit, VT));
+ AddToWorkList(X.Val);
+
+ SDOperand Cst = DAG.getNode(ISD::BIT_CONVERT, VT, N0.getOperand(0));
+ Cst = DAG.getNode(ISD::AND, VT, Cst, DAG.getConstant(~SignBit, VT));
+ AddToWorkList(Cst.Val);
+
+ return DAG.getNode(ISD::OR, VT, X, Cst);
+ }
+
return SDOperand();
}
if (isNegatibleForFree(N0))
return GetNegatedExpression(N0, DAG);
+ // Transform fneg(bitconvert(x)) -> bitconvert(x^sign) to avoid loading
+ // constant pool values.
+ if (N0.getOpcode() == ISD::BIT_CONVERT && N0.Val->hasOneUse() &&
+ MVT::isInteger(N0.getOperand(0).getValueType()) &&
+ !MVT::isVector(N0.getOperand(0).getValueType())) {
+ SDOperand Int = N0.getOperand(0);
+ MVT::ValueType IntVT = Int.getValueType();
+ if (MVT::isInteger(IntVT) && !MVT::isVector(IntVT)) {
+ Int = DAG.getNode(ISD::XOR, IntVT, Int,
+ DAG.getConstant(MVT::getIntVTSignBit(IntVT), IntVT));
+ AddToWorkList(Int.Val);
+ return DAG.getNode(ISD::BIT_CONVERT, N->getValueType(0), Int);
+ }
+ }
+
return SDOperand();
}
if (N0.getOpcode() == ISD::FNEG || N0.getOpcode() == ISD::FCOPYSIGN)
return DAG.getNode(ISD::FABS, VT, N0.getOperand(0));
+ // Transform fabs(bitconvert(x)) -> bitconvert(x&~sign) to avoid loading
+ // constant pool values.
+ if (N0.getOpcode() == ISD::BIT_CONVERT && N0.Val->hasOneUse() &&
+ MVT::isInteger(N0.getOperand(0).getValueType()) &&
+ !MVT::isVector(N0.getOperand(0).getValueType())) {
+ SDOperand Int = N0.getOperand(0);
+ MVT::ValueType IntVT = Int.getValueType();
+ if (MVT::isInteger(IntVT) && !MVT::isVector(IntVT)) {
+ Int = DAG.getNode(ISD::AND, IntVT, Int,
+ DAG.getConstant(~MVT::getIntVTSignBit(IntVT), IntVT));
+ AddToWorkList(Int.Val);
+ return DAG.getNode(ISD::BIT_CONVERT, N->getValueType(0), Int);
+ }
+ }
+
return SDOperand();
}
if (LoadSDNode *LD = dyn_cast<LoadSDNode>(N)) {
if (LD->isIndexed())
return false;
- VT = LD->getLoadedVT();
+ VT = LD->getMemoryVT();
if (!TLI.isIndexedLoadLegal(ISD::PRE_INC, VT) &&
!TLI.isIndexedLoadLegal(ISD::PRE_DEC, VT))
return false;
} else if (StoreSDNode *ST = dyn_cast<StoreSDNode>(N)) {
if (ST->isIndexed())
return false;
- VT = ST->getStoredVT();
+ VT = ST->getMemoryVT();
if (!TLI.isIndexedStoreLegal(ISD::PRE_INC, VT) &&
!TLI.isIndexedStoreLegal(ISD::PRE_DEC, VT))
return false;
if (LoadSDNode *LD = dyn_cast<LoadSDNode>(N)) {
if (LD->isIndexed())
return false;
- VT = LD->getLoadedVT();
+ VT = LD->getMemoryVT();
if (!TLI.isIndexedLoadLegal(ISD::POST_INC, VT) &&
!TLI.isIndexedLoadLegal(ISD::POST_DEC, VT))
return false;
} else if (StoreSDNode *ST = dyn_cast<StoreSDNode>(N)) {
if (ST->isIndexed())
return false;
- VT = ST->getStoredVT();
+ VT = ST->getMemoryVT();
if (!TLI.isIndexedStoreLegal(ISD::POST_INC, VT) &&
!TLI.isIndexedStoreLegal(ISD::POST_DEC, VT))
return false;
return false;
}
+/// InferAlignment - If we can infer some alignment information from this
+/// pointer, return it.
+static unsigned InferAlignment(SDOperand Ptr, SelectionDAG &DAG) {
+ // If this is a direct reference to a stack slot, use information about the
+ // stack slot's alignment.
+ int FrameIdx = 1 << 31;
+ int64_t FrameOffset = 0;
+ if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(Ptr)) {
+ FrameIdx = FI->getIndex();
+ } else if (Ptr.getOpcode() == ISD::ADD &&
+ isa<ConstantSDNode>(Ptr.getOperand(1)) &&
+ isa<FrameIndexSDNode>(Ptr.getOperand(0))) {
+ FrameIdx = cast<FrameIndexSDNode>(Ptr.getOperand(0))->getIndex();
+ FrameOffset = Ptr.getConstantOperandVal(1);
+ }
+
+ if (FrameIdx != (1 << 31)) {
+ // FIXME: Handle FI+CST.
+ const MachineFrameInfo &MFI = *DAG.getMachineFunction().getFrameInfo();
+ if (MFI.isFixedObjectIndex(FrameIdx)) {
+ int64_t ObjectOffset = MFI.getObjectOffset(FrameIdx);
+
+ // The alignment of the frame index can be determined from its offset from
+ // the incoming frame position. If the frame object is at offset 32 and
+ // the stack is guaranteed to be 16-byte aligned, then we know that the
+ // object is 16-byte aligned.
+ unsigned StackAlign = DAG.getTarget().getFrameInfo()->getStackAlignment();
+ unsigned Align = MinAlign(ObjectOffset, StackAlign);
+
+ // Finally, the frame object itself may have a known alignment. Factor
+ // the alignment + offset into a new alignment. For example, if we know
+ // the FI is 8 byte aligned, but the pointer is 4 off, we really have a
+ // 4-byte alignment of the resultant pointer. Likewise align 4 + 4-byte
+ // offset = 4-byte alignment, align 4 + 1-byte offset = align 1, etc.
+ unsigned FIInfoAlign = MinAlign(MFI.getObjectAlignment(FrameIdx),
+ FrameOffset);
+ return std::max(Align, FIInfoAlign);
+ }
+ }
+
+ return 0;
+}
SDOperand DAGCombiner::visitLOAD(SDNode *N) {
LoadSDNode *LD = cast<LoadSDNode>(N);
SDOperand Chain = LD->getChain();
SDOperand Ptr = LD->getBasePtr();
+
+ // Try to infer better alignment information than the load already has.
+ if (LD->isUnindexed()) {
+ if (unsigned Align = InferAlignment(Ptr, DAG)) {
+ if (Align > LD->getAlignment())
+ return DAG.getExtLoad(LD->getExtensionType(), LD->getValueType(0),
+ Chain, Ptr, LD->getSrcValue(),
+ LD->getSrcValueOffset(), LD->getMemoryVT(),
+ LD->isVolatile(), Align);
+ }
+ }
+
// If load is not volatile and there are no uses of the loaded value (and
// the updated indexed value in case of indexed loads), change uses of the
// v1, chain2 = load chain1, loc
// v2, chain3 = load chain2, loc
// v3 = add v2, c
- // Now we replace use of v1 with undef, use of chain2 with chain1.
- // ReplaceAllUsesWith() will iterate through uses of the first load and
- // update operands:
- // v1, chain2 = load chain1, loc
- // v2, chain3 = load chain1, loc
- // v3 = add v2, c
- // Now the second load is the same as the first load, SelectionDAG cse
- // will ensure the use of second load is replaced with the first load.
- // v1, chain2 = load chain1, loc
- // v3 = add v1, c
- // Then v1 is replaced with undef and bad things happen.
+ // Now we replace use of chain2 with chain1. This makes the second load
+ // isomorphic to the one we are deleting, and thus makes this load live.
std::vector<SDNode*> NowDead;
- SDOperand Undef = DAG.getNode(ISD::UNDEF, N->getValueType(0));
DOUT << "\nReplacing.6 "; DEBUG(N->dump(&DAG));
- DOUT << "\nWith: "; DEBUG(Undef.Val->dump(&DAG));
- DOUT << " and 1 other value\n";
- DAG.ReplaceAllUsesOfValueWith(SDOperand(N, 0), Undef, &NowDead);
+ DOUT << "\nWith chain: "; DEBUG(Chain.Val->dump(&DAG));
+ DOUT << "\n";
DAG.ReplaceAllUsesOfValueWith(SDOperand(N, 1), Chain, &NowDead);
- removeFromWorkList(N);
for (unsigned i = 0, e = NowDead.size(); i != e; ++i)
removeFromWorkList(NowDead[i]);
- DAG.DeleteNode(N);
+ if (N->use_empty()) {
+ removeFromWorkList(N);
+ DAG.DeleteNode(N);
+ }
return SDOperand(N, 0); // Return N so it doesn't get rechecked!
}
} else {
LD->getValueType(0),
BetterChain, Ptr, LD->getSrcValue(),
LD->getSrcValueOffset(),
- LD->getLoadedVT(),
+ LD->getMemoryVT(),
LD->isVolatile(),
LD->getAlignment());
}
SDOperand Value = ST->getValue();
SDOperand Ptr = ST->getBasePtr();
+ // Try to infer better alignment information than the store already has.
+ if (ST->isUnindexed()) {
+ if (unsigned Align = InferAlignment(Ptr, DAG)) {
+ if (Align > ST->getAlignment())
+ return DAG.getTruncStore(Chain, Value, Ptr, ST->getSrcValue(),
+ ST->getSrcValueOffset(), ST->getMemoryVT(),
+ ST->isVolatile(), Align);
+ }
+ }
+
// If this is a store of a bit convert, store the input value if the
// resultant store does not need a higher alignment than the original.
if (Value.getOpcode() == ISD::BIT_CONVERT && !ST->isTruncatingStore() &&
if (ST->isTruncatingStore()) {
ReplStore = DAG.getTruncStore(BetterChain, Value, Ptr,
ST->getSrcValue(),ST->getSrcValueOffset(),
- ST->getStoredVT(),
+ ST->getMemoryVT(),
ST->isVolatile(), ST->getAlignment());
} else {
ReplStore = DAG.getStore(BetterChain, Value, Ptr,
// only the low bits are being used. For example:
// "truncstore (or (shl x, 8), y), i8" -> "truncstore y, i8"
SDOperand Shorter =
- GetDemandedBits(Value, MVT::getIntVTBitMask(ST->getStoredVT()));
+ GetDemandedBits(Value, MVT::getIntVTBitMask(ST->getMemoryVT()));
AddToWorkList(Value.Val);
if (Shorter.Val)
return DAG.getTruncStore(Chain, Shorter, Ptr, ST->getSrcValue(),
- ST->getSrcValueOffset(), ST->getStoredVT(),
+ ST->getSrcValueOffset(), ST->getMemoryVT(),
ST->isVolatile(), ST->getAlignment());
// Otherwise, see if we can simplify the operation with
// SimplifyDemandedBits, which only works if the value has a single use.
- if (SimplifyDemandedBits(Value, MVT::getIntVTBitMask(ST->getStoredVT())))
+ if (SimplifyDemandedBits(Value, MVT::getIntVTBitMask(ST->getMemoryVT())))
return SDOperand(N, 0);
}
// If this is a load followed by a store to the same location, then the store
// is dead/noop.
if (LoadSDNode *Ld = dyn_cast<LoadSDNode>(Value)) {
- if (Ld->getBasePtr() == Ptr && ST->getStoredVT() == Ld->getLoadedVT() &&
+ if (Ld->getBasePtr() == Ptr && ST->getMemoryVT() == Ld->getMemoryVT() &&
ST->isUnindexed() && !ST->isVolatile() &&
// There can't be any side effects between the load and store, such as
// a call or store.
&& TLI.isTypeLegal(Value.getOperand(0).getValueType()) &&
Value.Val->hasOneUse() && ST->isUnindexed() &&
TLI.isTruncStoreLegal(Value.getOperand(0).getValueType(),
- ST->getStoredVT())) {
+ ST->getMemoryVT())) {
return DAG.getTruncStore(Chain, Value.getOperand(0), Ptr, ST->getSrcValue(),
- ST->getSrcValueOffset(), ST->getStoredVT(),
+ ST->getSrcValueOffset(), ST->getMemoryVT(),
ST->isVolatile(), ST->getAlignment());
}
LoadSDNode *RLD = cast<LoadSDNode>(RHS);
// If this is an EXTLOAD, the VT's must match.
- if (LLD->getLoadedVT() == RLD->getLoadedVT()) {
+ if (LLD->getMemoryVT() == RLD->getMemoryVT()) {
// FIXME: this conflates two src values, discarding one. This is not
// the right thing to do, but nothing uses srcvalues now. When they do,
// turn SrcValue into a list of locations.
TheSelect->getValueType(0),
LLD->getChain(), Addr, LLD->getSrcValue(),
LLD->getSrcValueOffset(),
- LLD->getLoadedVT(),
+ LLD->getMemoryVT(),
LLD->isVolatile(),
LLD->getAlignment());
}
const Value *&SrcValue, int &SrcValueOffset) {
if (LoadSDNode *LD = dyn_cast<LoadSDNode>(N)) {
Ptr = LD->getBasePtr();
- Size = MVT::getSizeInBits(LD->getLoadedVT()) >> 3;
+ Size = MVT::getSizeInBits(LD->getMemoryVT()) >> 3;
SrcValue = LD->getSrcValue();
SrcValueOffset = LD->getSrcValueOffset();
return true;
} else if (StoreSDNode *ST = dyn_cast<StoreSDNode>(N)) {
Ptr = ST->getBasePtr();
- Size = MVT::getSizeInBits(ST->getStoredVT()) >> 3;
+ Size = MVT::getSizeInBits(ST->getMemoryVT()) >> 3;
SrcValue = ST->getSrcValue();
SrcValueOffset = ST->getSrcValueOffset();
} else {
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