[PPC64LE] Recognize shufflevector patterns for little endian
Various masks on shufflevector instructions are recognizable as
specific PowerPC instructions (vector pack, vector merge, etc.).
There is existing code in PPCISelLowering.cpp to recognize the correct
patterns for big endian code. The masks for these instructions are
different for little endian code due to the big-endian numbering
employed by these instructions. This patch adds the recognition code
for little endian.
I've added a new test case test/CodeGen/PowerPC/vec_shuffle_le.ll for
this. The existing recognizer test (vec_shuffle.ll) is unnecessarily
verbose and difficult to read, so I felt it was better to add a new
test rather than modify the old one.
llvm-svn: 210536
diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
index b7d7aaa..d073512 100644
--- a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -856,15 +856,17 @@
/// isVPKUHUMShuffleMask - Return true if this is the shuffle mask for a
/// VPKUHUM instruction.
-bool PPC::isVPKUHUMShuffleMask(ShuffleVectorSDNode *N, bool isUnary) {
+bool PPC::isVPKUHUMShuffleMask(ShuffleVectorSDNode *N, bool isUnary,
+ SelectionDAG &DAG) {
+ unsigned j = DAG.getTarget().getDataLayout()->isLittleEndian() ? 0 : 1;
if (!isUnary) {
for (unsigned i = 0; i != 16; ++i)
- if (!isConstantOrUndef(N->getMaskElt(i), i*2+1))
+ if (!isConstantOrUndef(N->getMaskElt(i), i*2+j))
return false;
} else {
for (unsigned i = 0; i != 8; ++i)
- if (!isConstantOrUndef(N->getMaskElt(i), i*2+1) ||
- !isConstantOrUndef(N->getMaskElt(i+8), i*2+1))
+ if (!isConstantOrUndef(N->getMaskElt(i), i*2+j) ||
+ !isConstantOrUndef(N->getMaskElt(i+8), i*2+j))
return false;
}
return true;
@@ -872,18 +874,27 @@
/// isVPKUWUMShuffleMask - Return true if this is the shuffle mask for a
/// VPKUWUM instruction.
-bool PPC::isVPKUWUMShuffleMask(ShuffleVectorSDNode *N, bool isUnary) {
+bool PPC::isVPKUWUMShuffleMask(ShuffleVectorSDNode *N, bool isUnary,
+ SelectionDAG &DAG) {
+ unsigned j, k;
+ if (DAG.getTarget().getDataLayout()->isLittleEndian()) {
+ j = 0;
+ k = 1;
+ } else {
+ j = 2;
+ k = 3;
+ }
if (!isUnary) {
for (unsigned i = 0; i != 16; i += 2)
- if (!isConstantOrUndef(N->getMaskElt(i ), i*2+2) ||
- !isConstantOrUndef(N->getMaskElt(i+1), i*2+3))
+ if (!isConstantOrUndef(N->getMaskElt(i ), i*2+j) ||
+ !isConstantOrUndef(N->getMaskElt(i+1), i*2+k))
return false;
} else {
for (unsigned i = 0; i != 8; i += 2)
- if (!isConstantOrUndef(N->getMaskElt(i ), i*2+2) ||
- !isConstantOrUndef(N->getMaskElt(i+1), i*2+3) ||
- !isConstantOrUndef(N->getMaskElt(i+8), i*2+2) ||
- !isConstantOrUndef(N->getMaskElt(i+9), i*2+3))
+ if (!isConstantOrUndef(N->getMaskElt(i ), i*2+j) ||
+ !isConstantOrUndef(N->getMaskElt(i+1), i*2+k) ||
+ !isConstantOrUndef(N->getMaskElt(i+8), i*2+j) ||
+ !isConstantOrUndef(N->getMaskElt(i+9), i*2+k))
return false;
}
return true;
@@ -910,27 +921,39 @@
}
/// isVMRGLShuffleMask - Return true if this is a shuffle mask suitable for
-/// a VRGL* instruction with the specified unit size (1,2 or 4 bytes).
+/// a VMRGL* instruction with the specified unit size (1,2 or 4 bytes).
bool PPC::isVMRGLShuffleMask(ShuffleVectorSDNode *N, unsigned UnitSize,
- bool isUnary) {
- if (!isUnary)
- return isVMerge(N, UnitSize, 8, 24);
- return isVMerge(N, UnitSize, 8, 8);
+ bool isUnary, SelectionDAG &DAG) {
+ if (DAG.getTarget().getDataLayout()->isLittleEndian()) {
+ if (!isUnary)
+ return isVMerge(N, UnitSize, 0, 16);
+ return isVMerge(N, UnitSize, 0, 0);
+ } else {
+ if (!isUnary)
+ return isVMerge(N, UnitSize, 8, 24);
+ return isVMerge(N, UnitSize, 8, 8);
+ }
}
/// isVMRGHShuffleMask - Return true if this is a shuffle mask suitable for
-/// a VRGH* instruction with the specified unit size (1,2 or 4 bytes).
+/// a VMRGH* instruction with the specified unit size (1,2 or 4 bytes).
bool PPC::isVMRGHShuffleMask(ShuffleVectorSDNode *N, unsigned UnitSize,
- bool isUnary) {
- if (!isUnary)
- return isVMerge(N, UnitSize, 0, 16);
- return isVMerge(N, UnitSize, 0, 0);
+ bool isUnary, SelectionDAG &DAG) {
+ if (DAG.getTarget().getDataLayout()->isLittleEndian()) {
+ if (!isUnary)
+ return isVMerge(N, UnitSize, 8, 24);
+ return isVMerge(N, UnitSize, 8, 8);
+ } else {
+ if (!isUnary)
+ return isVMerge(N, UnitSize, 0, 16);
+ return isVMerge(N, UnitSize, 0, 0);
+ }
}
/// isVSLDOIShuffleMask - If this is a vsldoi shuffle mask, return the shift
/// amount, otherwise return -1.
-int PPC::isVSLDOIShuffleMask(SDNode *N, bool isUnary) {
+int PPC::isVSLDOIShuffleMask(SDNode *N, bool isUnary, SelectionDAG &DAG) {
if (N->getValueType(0) != MVT::v16i8)
return -1;
@@ -947,18 +970,38 @@
// numbered from this value.
unsigned ShiftAmt = SVOp->getMaskElt(i);
if (ShiftAmt < i) return -1;
- ShiftAmt -= i;
- if (!isUnary) {
- // Check the rest of the elements to see if they are consecutive.
- for (++i; i != 16; ++i)
- if (!isConstantOrUndef(SVOp->getMaskElt(i), ShiftAmt+i))
- return -1;
- } else {
- // Check the rest of the elements to see if they are consecutive.
- for (++i; i != 16; ++i)
- if (!isConstantOrUndef(SVOp->getMaskElt(i), (ShiftAmt+i) & 15))
- return -1;
+ if (DAG.getTarget().getDataLayout()->isLittleEndian()) {
+
+ ShiftAmt += i;
+
+ if (!isUnary) {
+ // Check the rest of the elements to see if they are consecutive.
+ for (++i; i != 16; ++i)
+ if (!isConstantOrUndef(SVOp->getMaskElt(i), ShiftAmt - i))
+ return -1;
+ } else {
+ // Check the rest of the elements to see if they are consecutive.
+ for (++i; i != 16; ++i)
+ if (!isConstantOrUndef(SVOp->getMaskElt(i), (ShiftAmt - i) & 15))
+ return -1;
+ }
+
+ } else { // Big Endian
+
+ ShiftAmt -= i;
+
+ if (!isUnary) {
+ // Check the rest of the elements to see if they are consecutive.
+ for (++i; i != 16; ++i)
+ if (!isConstantOrUndef(SVOp->getMaskElt(i), ShiftAmt+i))
+ return -1;
+ } else {
+ // Check the rest of the elements to see if they are consecutive.
+ for (++i; i != 16; ++i)
+ if (!isConstantOrUndef(SVOp->getMaskElt(i), (ShiftAmt+i) & 15))
+ return -1;
+ }
}
return ShiftAmt;
}
@@ -1011,10 +1054,14 @@
/// getVSPLTImmediate - Return the appropriate VSPLT* immediate to splat the
/// specified isSplatShuffleMask VECTOR_SHUFFLE mask.
-unsigned PPC::getVSPLTImmediate(SDNode *N, unsigned EltSize) {
+unsigned PPC::getVSPLTImmediate(SDNode *N, unsigned EltSize,
+ SelectionDAG &DAG) {
ShuffleVectorSDNode *SVOp = cast<ShuffleVectorSDNode>(N);
assert(isSplatShuffleMask(SVOp, EltSize));
- return SVOp->getMaskElt(0) / EltSize;
+ if (DAG.getTarget().getDataLayout()->isLittleEndian())
+ return (16 / EltSize) - 1 - (SVOp->getMaskElt(0) / EltSize);
+ else
+ return SVOp->getMaskElt(0) / EltSize;
}
/// get_VSPLTI_elt - If this is a build_vector of constants which can be formed
@@ -5742,6 +5789,7 @@
SDValue V2 = Op.getOperand(1);
ShuffleVectorSDNode *SVOp = cast<ShuffleVectorSDNode>(Op);
EVT VT = Op.getValueType();
+ bool isLittleEndian = PPCSubTarget.isLittleEndian();
// Cases that are handled by instructions that take permute immediates
// (such as vsplt*) should be left as VECTOR_SHUFFLE nodes so they can be
@@ -5750,15 +5798,15 @@
if (PPC::isSplatShuffleMask(SVOp, 1) ||
PPC::isSplatShuffleMask(SVOp, 2) ||
PPC::isSplatShuffleMask(SVOp, 4) ||
- PPC::isVPKUWUMShuffleMask(SVOp, true) ||
- PPC::isVPKUHUMShuffleMask(SVOp, true) ||
- PPC::isVSLDOIShuffleMask(SVOp, true) != -1 ||
- PPC::isVMRGLShuffleMask(SVOp, 1, true) ||
- PPC::isVMRGLShuffleMask(SVOp, 2, true) ||
- PPC::isVMRGLShuffleMask(SVOp, 4, true) ||
- PPC::isVMRGHShuffleMask(SVOp, 1, true) ||
- PPC::isVMRGHShuffleMask(SVOp, 2, true) ||
- PPC::isVMRGHShuffleMask(SVOp, 4, true)) {
+ PPC::isVPKUWUMShuffleMask(SVOp, true, DAG) ||
+ PPC::isVPKUHUMShuffleMask(SVOp, true, DAG) ||
+ PPC::isVSLDOIShuffleMask(SVOp, true, DAG) != -1 ||
+ PPC::isVMRGLShuffleMask(SVOp, 1, true, DAG) ||
+ PPC::isVMRGLShuffleMask(SVOp, 2, true, DAG) ||
+ PPC::isVMRGLShuffleMask(SVOp, 4, true, DAG) ||
+ PPC::isVMRGHShuffleMask(SVOp, 1, true, DAG) ||
+ PPC::isVMRGHShuffleMask(SVOp, 2, true, DAG) ||
+ PPC::isVMRGHShuffleMask(SVOp, 4, true, DAG)) {
return Op;
}
}
@@ -5766,15 +5814,15 @@
// Altivec has a variety of "shuffle immediates" that take two vector inputs
// and produce a fixed permutation. If any of these match, do not lower to
// VPERM.
- if (PPC::isVPKUWUMShuffleMask(SVOp, false) ||
- PPC::isVPKUHUMShuffleMask(SVOp, false) ||
- PPC::isVSLDOIShuffleMask(SVOp, false) != -1 ||
- PPC::isVMRGLShuffleMask(SVOp, 1, false) ||
- PPC::isVMRGLShuffleMask(SVOp, 2, false) ||
- PPC::isVMRGLShuffleMask(SVOp, 4, false) ||
- PPC::isVMRGHShuffleMask(SVOp, 1, false) ||
- PPC::isVMRGHShuffleMask(SVOp, 2, false) ||
- PPC::isVMRGHShuffleMask(SVOp, 4, false))
+ if (PPC::isVPKUWUMShuffleMask(SVOp, false, DAG) ||
+ PPC::isVPKUHUMShuffleMask(SVOp, false, DAG) ||
+ PPC::isVSLDOIShuffleMask(SVOp, false, DAG) != -1 ||
+ PPC::isVMRGLShuffleMask(SVOp, 1, false, DAG) ||
+ PPC::isVMRGLShuffleMask(SVOp, 2, false, DAG) ||
+ PPC::isVMRGLShuffleMask(SVOp, 4, false, DAG) ||
+ PPC::isVMRGHShuffleMask(SVOp, 1, false, DAG) ||
+ PPC::isVMRGHShuffleMask(SVOp, 2, false, DAG) ||
+ PPC::isVMRGHShuffleMask(SVOp, 4, false, DAG))
return Op;
// Check to see if this is a shuffle of 4-byte values. If so, we can use our
@@ -5808,7 +5856,9 @@
// If this shuffle can be expressed as a shuffle of 4-byte elements, use the
// perfect shuffle vector to determine if it is cost effective to do this as
// discrete instructions, or whether we should use a vperm.
- if (isFourElementShuffle) {
+ // For now, we skip this for little endian until such time as we have a
+ // little-endian perfect shuffle table.
+ if (isFourElementShuffle && !isLittleEndian) {
// Compute the index in the perfect shuffle table.
unsigned PFTableIndex =
PFIndexes[0]*9*9*9+PFIndexes[1]*9*9+PFIndexes[2]*9+PFIndexes[3];
@@ -5844,7 +5894,6 @@
// instruction.
EVT EltVT = V1.getValueType().getVectorElementType();
unsigned BytesPerElement = EltVT.getSizeInBits()/8;
- bool isLittleEndian = PPCSubTarget.isLittleEndian();
SmallVector<SDValue, 16> ResultMask;
for (unsigned i = 0, e = VT.getVectorNumElements(); i != e; ++i) {