Introduce the BuildVectorSDNode class that encapsulates the ISD::BUILD_VECTOR
instruction. The class also consolidates the code for detecting constant
splats that's shared across PowerPC and the CellSPU backends (and might be
useful for other backends.) Also introduces SelectionDAG::getBUID_VECTOR() for
generating new BUILD_VECTOR nodes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65296 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/PPCISelLowering.cpp b/lib/Target/PowerPC/PPCISelLowering.cpp
index 2c97b99..8368380 100644
--- a/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -3093,100 +3093,6 @@
// Vector related lowering.
//
-// If this is a vector of constants or undefs, get the bits. A bit in
-// UndefBits is set if the corresponding element of the vector is an
-// ISD::UNDEF value. For undefs, the corresponding VectorBits values are
-// zero. Return true if this is not an array of constants, false if it is.
-//
-static bool GetConstantBuildVectorBits(SDNode *BV, uint64_t VectorBits[2],
- uint64_t UndefBits[2]) {
- // Start with zero'd results.
- VectorBits[0] = VectorBits[1] = UndefBits[0] = UndefBits[1] = 0;
-
- unsigned EltBitSize = BV->getOperand(0).getValueType().getSizeInBits();
- for (unsigned i = 0, e = BV->getNumOperands(); i != e; ++i) {
- SDValue OpVal = BV->getOperand(i);
-
- unsigned PartNo = i >= e/2; // In the upper 128 bits?
- unsigned SlotNo = e/2 - (i & (e/2-1))-1; // Which subpiece of the uint64_t.
-
- uint64_t EltBits = 0;
- if (OpVal.getOpcode() == ISD::UNDEF) {
- uint64_t EltUndefBits = ~0U >> (32-EltBitSize);
- UndefBits[PartNo] |= EltUndefBits << (SlotNo*EltBitSize);
- continue;
- } else if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(OpVal)) {
- EltBits = CN->getZExtValue() & (~0U >> (32-EltBitSize));
- } else if (ConstantFPSDNode *CN = dyn_cast<ConstantFPSDNode>(OpVal)) {
- assert(CN->getValueType(0) == MVT::f32 &&
- "Only one legal FP vector type!");
- EltBits = FloatToBits(CN->getValueAPF().convertToFloat());
- } else {
- // Nonconstant element.
- return true;
- }
-
- VectorBits[PartNo] |= EltBits << (SlotNo*EltBitSize);
- }
-
- //printf("%llx %llx %llx %llx\n",
- // VectorBits[0], VectorBits[1], UndefBits[0], UndefBits[1]);
- return false;
-}
-
-// If this is a splat (repetition) of a value across the whole vector, return
-// the smallest size that splats it. For example, "0x01010101010101..." is a
-// splat of 0x01, 0x0101, and 0x01010101. We return SplatBits = 0x01 and
-// SplatSize = 1 byte.
-static bool isConstantSplat(const uint64_t Bits128[2],
- const uint64_t Undef128[2],
- unsigned &SplatBits, unsigned &SplatUndef,
- unsigned &SplatSize) {
-
- // Don't let undefs prevent splats from matching. See if the top 64-bits are
- // the same as the lower 64-bits, ignoring undefs.
- if ((Bits128[0] & ~Undef128[1]) != (Bits128[1] & ~Undef128[0]))
- return false; // Can't be a splat if two pieces don't match.
-
- uint64_t Bits64 = Bits128[0] | Bits128[1];
- uint64_t Undef64 = Undef128[0] & Undef128[1];
-
- // Check that the top 32-bits are the same as the lower 32-bits, ignoring
- // undefs.
- if ((Bits64 & (~Undef64 >> 32)) != ((Bits64 >> 32) & ~Undef64))
- return false; // Can't be a splat if two pieces don't match.
-
- uint32_t Bits32 = uint32_t(Bits64) | uint32_t(Bits64 >> 32);
- uint32_t Undef32 = uint32_t(Undef64) & uint32_t(Undef64 >> 32);
-
- // If the top 16-bits are different than the lower 16-bits, ignoring
- // undefs, we have an i32 splat.
- if ((Bits32 & (~Undef32 >> 16)) != ((Bits32 >> 16) & ~Undef32)) {
- SplatBits = Bits32;
- SplatUndef = Undef32;
- SplatSize = 4;
- return true;
- }
-
- uint16_t Bits16 = uint16_t(Bits32) | uint16_t(Bits32 >> 16);
- uint16_t Undef16 = uint16_t(Undef32) & uint16_t(Undef32 >> 16);
-
- // If the top 8-bits are different than the lower 8-bits, ignoring
- // undefs, we have an i16 splat.
- if ((Bits16 & (uint16_t(~Undef16) >> 8)) != ((Bits16 >> 8) & ~Undef16)) {
- SplatBits = Bits16;
- SplatUndef = Undef16;
- SplatSize = 2;
- return true;
- }
-
- // Otherwise, we have an 8-bit splat.
- SplatBits = uint8_t(Bits16) | uint8_t(Bits16 >> 8);
- SplatUndef = uint8_t(Undef16) & uint8_t(Undef16 >> 8);
- SplatSize = 1;
- return true;
-}
-
/// BuildSplatI - Build a canonical splati of Val with an element size of
/// SplatSize. Cast the result to VT.
static SDValue BuildSplatI(int Val, unsigned SplatSize, MVT VT,
@@ -3209,8 +3115,7 @@
SDValue Elt = DAG.getConstant(Val, CanonicalVT.getVectorElementType());
SmallVector<SDValue, 8> Ops;
Ops.assign(CanonicalVT.getVectorNumElements(), Elt);
- SDValue Res = DAG.getNode(ISD::BUILD_VECTOR, dl, CanonicalVT,
- &Ops[0], Ops.size());
+ SDValue Res = DAG.getBUILD_VECTOR(CanonicalVT, dl, &Ops[0], Ops.size());
return DAG.getNode(ISD::BIT_CONVERT, dl, ReqVT, Res);
}
@@ -3247,7 +3152,7 @@
for (unsigned i = 0; i != 16; ++i)
Ops[i] = DAG.getConstant(i+Amt, MVT::i8);
SDValue T = DAG.getNode(ISD::VECTOR_SHUFFLE, dl, MVT::v16i8, LHS, RHS,
- DAG.getNode(ISD::BUILD_VECTOR, dl, MVT::v16i8, Ops,16));
+ DAG.getBUILD_VECTOR(MVT::v16i8, dl, Ops,16));
return DAG.getNode(ISD::BIT_CONVERT, dl, VT, T);
}
@@ -3262,19 +3167,19 @@
// UndefBits is set if the corresponding element of the vector is an
// ISD::UNDEF value. For undefs, the corresponding VectorBits values are
// zero.
- uint64_t VectorBits[2];
- uint64_t UndefBits[2];
DebugLoc dl = Op.getDebugLoc();
- if (GetConstantBuildVectorBits(Op.getNode(), VectorBits, UndefBits))
- return SDValue(); // Not a constant vector.
+ BuildVectorSDNode *BVN = dyn_cast<BuildVectorSDNode>(Op.getNode());
+ assert(BVN != 0 && "Expected a BuildVectorSDNode in LowerBUILD_VECTOR");
// If this is a splat (repetition) of a value across the whole vector, return
// the smallest size that splats it. For example, "0x01010101010101..." is a
// splat of 0x01, 0x0101, and 0x01010101. We return SplatBits = 0x01 and
// SplatSize = 1 byte.
- unsigned SplatBits, SplatUndef, SplatSize;
- if (isConstantSplat(VectorBits, UndefBits, SplatBits, SplatUndef, SplatSize)){
- bool HasAnyUndefs = (UndefBits[0] | UndefBits[1]) != 0;
+ if (BVN->isConstantSplat()) {
+ uint64_t SplatBits = BVN->getSplatBits();
+ uint64_t SplatUndef = BVN->getSplatUndef();
+ unsigned SplatSize = BVN->getSplatSize();
+ bool HasAnyUndefs = BVN->hasAnyUndefBits();
// First, handle single instruction cases.
@@ -3283,7 +3188,7 @@
// Canonicalize all zero vectors to be v4i32.
if (Op.getValueType() != MVT::v4i32 || HasAnyUndefs) {
SDValue Z = DAG.getConstant(0, MVT::i32);
- Z = DAG.getNode(ISD::BUILD_VECTOR, dl, MVT::v4i32, Z, Z, Z, Z);
+ Z = DAG.getBUILD_VECTOR(MVT::v4i32, dl, Z, Z, Z, Z);
Op = DAG.getNode(ISD::BIT_CONVERT, dl, Op.getValueType(), Z);
}
return Op;
@@ -3496,7 +3401,7 @@
return DAG.getNode(ISD::VECTOR_SHUFFLE, dl, OpLHS.getValueType(),
OpLHS, OpRHS,
- DAG.getNode(ISD::BUILD_VECTOR, dl, MVT::v16i8, Ops, 16));
+ DAG.getBUILD_VECTOR(MVT::v16i8, dl, Ops, 16));
}
/// LowerVECTOR_SHUFFLE - Return the code we lower for VECTOR_SHUFFLE. If this
@@ -3619,8 +3524,8 @@
MVT::i8));
}
- SDValue VPermMask = DAG.getNode(ISD::BUILD_VECTOR, dl, MVT::v16i8,
- &ResultMask[0], ResultMask.size());
+ SDValue VPermMask = DAG.getBUILD_VECTOR(MVT::v16i8, dl,
+ &ResultMask[0], ResultMask.size());
return DAG.getNode(PPCISD::VPERM, dl, V1.getValueType(), V1, V2, VPermMask);
}
@@ -3808,7 +3713,7 @@
Ops[i*2+1] = DAG.getConstant(2*i+1+16, MVT::i8);
}
return DAG.getNode(ISD::VECTOR_SHUFFLE, dl, MVT::v16i8, EvenParts, OddParts,
- DAG.getNode(ISD::BUILD_VECTOR, dl, MVT::v16i8, Ops, 16));
+ DAG.getBUILD_VECTOR(MVT::v16i8, dl, Ops, 16));
} else {
assert(0 && "Unknown mul to lower!");
abort();