[llvm] r225056 - [PowerPC] Improve instruction selection bit-permuting operations (64-bit)

Hal Finkel hfinkel at anl.gov
Wed Dec 31 18:53:30 PST 2014


Author: hfinkel
Date: Wed Dec 31 20:53:29 2014
New Revision: 225056

URL: http://llvm.org/viewvc/llvm-project?rev=225056&view=rev
Log:
[PowerPC] Improve instruction selection bit-permuting operations (64-bit)

This is the second installment of improvements to instruction selection for "bit
permutation" instruction sequences. r224318 added logic for instruction
selection for 32-bit bit permutation sequences, and this adds lowering for
64-bit sequences. The 64-bit sequences are more complicated than the 32-bit
ones because:
  a) the 64-bit versions of the 32-bit rotate-and-mask instructions
     work by replicating the lower 32-bits of the value-to-be-rotated into the
     upper 32 bits -- and integrating this into the cost modeling for the various
     bit group operations is non-trivial
  b) unlike the 32-bit instructions in 32-bit mode, the rotate-and-mask instructions
     cannot, in one instruction, specify the
     mask starting index, the mask ending index, and the rotation factor. Also,
     forming arbitrary 64-bit constants is more complicated than in 32-bit mode
     because the number of instructions necessary is value dependent.

Plus, support for 'late masking' was added: it is sometimes more efficient to
treat the overall value as if it had no mandatory zero bits when planning the
bit-group insertions, and then mask them in at the very end. Unfortunately, as
the structure of the bit groups is different in the two cases, the more
feasible implementation technique was to generate both instruction sequences,
and then pick the shorter one.

And finally, we now generate reasonable code for i64 bswap:

        rldicl 5, 3, 16, 0
        rldicl 4, 3, 8, 0
        rldicl 6, 3, 24, 0
        rldimi 4, 5, 8, 48
        rldicl 5, 3, 32, 0
        rldimi 4, 6, 16, 40
        rldicl 6, 3, 48, 0
        rldimi 4, 5, 24, 32
        rldicl 5, 3, 56, 0
        rldimi 4, 6, 40, 16
        rldimi 4, 5, 48, 8
        rldimi 4, 3, 56, 0

vs. what we used to produce:

        li 4, 255
        rldicl 5, 3, 24, 40
        rldicl 6, 3, 40, 24
        rldicl 7, 3, 56, 8
        sldi 8, 3, 8
        sldi 10, 3, 24
        sldi 12, 3, 40
        rldicl 0, 3, 8, 56
        sldi 9, 4, 32
        sldi 11, 4, 40
        sldi 4, 4, 48
        andi. 5, 5, 65280
        andis. 6, 6, 255
        andis. 7, 7, 65280
        sldi 3, 3, 56
        and 8, 8, 9
        and 4, 12, 4
        and 9, 10, 11
        or 6, 7, 6
        or 5, 5, 0
        or 3, 3, 4
        or 7, 9, 8
        or 4, 6, 5
        or 3, 3, 7
        or 3, 3, 4

which is 12 instructions, instead of 25, and seems optimal (at least in terms
of code size).

Modified:
    llvm/trunk/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
    llvm/trunk/lib/Target/PowerPC/PPCInstr64Bit.td
    llvm/trunk/test/CodeGen/PowerPC/bperm.ll

Modified: llvm/trunk/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/PowerPC/PPCISelDAGToDAG.cpp?rev=225056&r1=225055&r2=225056&view=diff
==============================================================================
--- llvm/trunk/lib/Target/PowerPC/PPCISelDAGToDAG.cpp (original)
+++ llvm/trunk/lib/Target/PowerPC/PPCISelDAGToDAG.cpp Wed Dec 31 20:53:29 2014
@@ -42,6 +42,12 @@ using namespace llvm;
 cl::opt<bool> ANDIGlueBug("expose-ppc-andi-glue-bug",
 cl::desc("expose the ANDI glue bug on PPC"), cl::Hidden);
 
+cl::opt<bool> UseBitPermRewriter("ppc-use-bit-perm-rewriter", cl::init(true),
+  cl::desc("use aggressive ppc isel for bit permutations"), cl::Hidden);
+cl::opt<bool> BPermRewriterNoMasking("ppc-bit-perm-rewriter-stress-rotates",
+  cl::desc("stress rotate selection in aggressive ppc isel for "
+           "bit permutations"), cl::Hidden);
+
 namespace llvm {
   void initializePPCDAGToDAGISelPass(PassRegistry&);
 }
@@ -533,6 +539,152 @@ SDNode *PPCDAGToDAGISel::SelectBitfieldI
   return nullptr;
 }
 
+// Predict the number of instructions that would be generated by calling
+// SelectInt64(N).
+static unsigned SelectInt64Count(int64_t Imm) {
+  // Assume no remaining bits.
+  unsigned Remainder = 0;
+  // Assume no shift required.
+  unsigned Shift = 0;
+
+  // If it can't be represented as a 32 bit value.
+  if (!isInt<32>(Imm)) {
+    Shift = countTrailingZeros<uint64_t>(Imm);
+    int64_t ImmSh = static_cast<uint64_t>(Imm) >> Shift;
+
+    // If the shifted value fits 32 bits.
+    if (isInt<32>(ImmSh)) {
+      // Go with the shifted value.
+      Imm = ImmSh;
+    } else {
+      // Still stuck with a 64 bit value.
+      Remainder = Imm;
+      Shift = 32;
+      Imm >>= 32;
+    }
+  }
+
+  // Intermediate operand.
+  unsigned Result = 0;
+
+  // Handle first 32 bits.
+  unsigned Lo = Imm & 0xFFFF;
+  unsigned Hi = (Imm >> 16) & 0xFFFF;
+
+  // Simple value.
+  if (isInt<16>(Imm)) {
+    // Just the Lo bits.
+    ++Result;
+  } else if (Lo) {
+    // Handle the Hi bits and Lo bits.
+    Result += 2;
+  } else {
+    // Just the Hi bits.
+    ++Result;
+  }
+
+  // If no shift, we're done.
+  if (!Shift) return Result;
+
+  // Shift for next step if the upper 32-bits were not zero.
+  if (Imm)
+    ++Result;
+
+  // Add in the last bits as required.
+  if ((Hi = (Remainder >> 16) & 0xFFFF))
+    ++Result;
+  if ((Lo = Remainder & 0xFFFF))
+    ++Result;
+
+  return Result;
+}
+
+// Select a 64-bit constant. For cost-modeling purposes, SelectInt64Count
+// (above) needs to be kept in sync with this function.
+static SDNode *SelectInt64(SelectionDAG *CurDAG, SDLoc dl, int64_t Imm) {
+  // Assume no remaining bits.
+  unsigned Remainder = 0;
+  // Assume no shift required.
+  unsigned Shift = 0;
+
+  // If it can't be represented as a 32 bit value.
+  if (!isInt<32>(Imm)) {
+    Shift = countTrailingZeros<uint64_t>(Imm);
+    int64_t ImmSh = static_cast<uint64_t>(Imm) >> Shift;
+
+    // If the shifted value fits 32 bits.
+    if (isInt<32>(ImmSh)) {
+      // Go with the shifted value.
+      Imm = ImmSh;
+    } else {
+      // Still stuck with a 64 bit value.
+      Remainder = Imm;
+      Shift = 32;
+      Imm >>= 32;
+    }
+  }
+
+  // Intermediate operand.
+  SDNode *Result;
+
+  // Handle first 32 bits.
+  unsigned Lo = Imm & 0xFFFF;
+  unsigned Hi = (Imm >> 16) & 0xFFFF;
+
+  auto getI32Imm = [CurDAG](unsigned Imm) {
+      return CurDAG->getTargetConstant(Imm, MVT::i32);
+  };
+
+  // Simple value.
+  if (isInt<16>(Imm)) {
+    // Just the Lo bits.
+    Result = CurDAG->getMachineNode(PPC::LI8, dl, MVT::i64, getI32Imm(Lo));
+  } else if (Lo) {
+    // Handle the Hi bits.
+    unsigned OpC = Hi ? PPC::LIS8 : PPC::LI8;
+    Result = CurDAG->getMachineNode(OpC, dl, MVT::i64, getI32Imm(Hi));
+    // And Lo bits.
+    Result = CurDAG->getMachineNode(PPC::ORI8, dl, MVT::i64,
+                                    SDValue(Result, 0), getI32Imm(Lo));
+  } else {
+    // Just the Hi bits.
+    Result = CurDAG->getMachineNode(PPC::LIS8, dl, MVT::i64, getI32Imm(Hi));
+  }
+
+  // If no shift, we're done.
+  if (!Shift) return Result;
+
+  // Shift for next step if the upper 32-bits were not zero.
+  if (Imm) {
+    Result = CurDAG->getMachineNode(PPC::RLDICR, dl, MVT::i64,
+                                    SDValue(Result, 0),
+                                    getI32Imm(Shift),
+                                    getI32Imm(63 - Shift));
+  }
+
+  // Add in the last bits as required.
+  if ((Hi = (Remainder >> 16) & 0xFFFF)) {
+    Result = CurDAG->getMachineNode(PPC::ORIS8, dl, MVT::i64,
+                                    SDValue(Result, 0), getI32Imm(Hi));
+  }
+  if ((Lo = Remainder & 0xFFFF)) {
+    Result = CurDAG->getMachineNode(PPC::ORI8, dl, MVT::i64,
+                                    SDValue(Result, 0), getI32Imm(Lo));
+  }
+
+  return Result;
+}
+
+// Select a 64-bit constant.
+static SDNode *SelectInt64(SelectionDAG *CurDAG, SDNode *N) {
+  SDLoc dl(N);
+
+  // Get 64 bit value.
+  int64_t Imm = cast<ConstantSDNode>(N)->getZExtValue();
+  return SelectInt64(CurDAG, dl, Imm);
+}
+
+
 namespace {
 class BitPermutationSelector {
   struct ValueBit {
@@ -577,8 +729,19 @@ class BitPermutationSelector {
     unsigned RLAmt;
     unsigned StartIdx, EndIdx;
 
+    // This rotation amount assumes that the lower 32 bits of the quantity are
+    // replicated in the high 32 bits by the rotation operator (which is done
+    // by rlwinm and friends in 64-bit mode).
+    bool Repl32;
+    // Did converting to Repl32 == true change the rotation factor? If it did,
+    // it decreased it by 32.
+    bool Repl32CR;
+    // Was this group coalesced after setting Repl32 to true?
+    bool Repl32Coalesced;
+
     BitGroup(SDValue V, unsigned R, unsigned S, unsigned E)
-      : V(V), RLAmt(R), StartIdx(S), EndIdx(E) {
+      : V(V), RLAmt(R), StartIdx(S), EndIdx(E), Repl32(false), Repl32CR(false),
+        Repl32Coalesced(false) {
       DEBUG(dbgs() << "\tbit group for " << V.getNode() << " RLAmt = " << R <<
                       " [" << S << ", " << E << "]\n");
     }
@@ -591,14 +754,23 @@ class BitPermutationSelector {
     unsigned RLAmt;
     unsigned NumGroups;
     unsigned FirstGroupStartIdx;
+    bool Repl32;
 
     ValueRotInfo()
-      : RLAmt(UINT32_MAX), NumGroups(0), FirstGroupStartIdx(UINT32_MAX) {}
+      : RLAmt(UINT32_MAX), NumGroups(0), FirstGroupStartIdx(UINT32_MAX),
+        Repl32(false) {}
 
     // For sorting (in reverse order) by NumGroups, and then by
     // FirstGroupStartIdx.
     bool operator < (const ValueRotInfo &Other) const {
-      if (NumGroups > Other.NumGroups)
+      // We need to sort so that the non-Repl32 come first because, when we're
+      // doing masking, the Repl32 bit groups might be subsumed into the 64-bit
+      // masking operation.
+      if (Repl32 < Other.Repl32)
+        return true;
+      else if (Repl32 > Other.Repl32)
+        return false;
+      else if (NumGroups > Other.NumGroups)
         return true;
       else if (NumGroups < Other.NumGroups)
         return false;
@@ -729,8 +901,9 @@ class BitPermutationSelector {
   }
 
   // Collect groups of consecutive bits with the same underlying value and
-  // rotation factor.
-  void collectBitGroups() {
+  // rotation factor. If we're doing late masking, we ignore zeros, otherwise
+  // they break up groups.
+  void collectBitGroups(bool LateMask) {
     BitGroups.clear();
 
     unsigned LastRLAmt = RLAmt[0];
@@ -739,6 +912,14 @@ class BitPermutationSelector {
     for (unsigned i = 1; i < Bits.size(); ++i) {
       unsigned ThisRLAmt = RLAmt[i];
       SDValue ThisValue = Bits[i].hasValue() ? Bits[i].getValue() : SDValue();
+      if (LateMask && !ThisValue) {
+        ThisValue = LastValue;
+        ThisRLAmt = LastRLAmt;
+        // If we're doing late masking, then the first bit group always starts
+        // at zero (even if the first bits were zero).
+        if (BitGroups.empty())
+          LastGroupStartIdx = 0;
+      }
 
       // If this bit has the same underlying value and the same rotate factor as
       // the last one, then they're part of the same group.
@@ -768,6 +949,7 @@ class BitPermutationSelector {
           BitGroups[BitGroups.size()-1].EndIdx == Bits.size()-1 &&
           BitGroups[0].V == BitGroups[BitGroups.size()-1].V &&
           BitGroups[0].RLAmt == BitGroups[BitGroups.size()-1].RLAmt) {
+        DEBUG(dbgs() << "\tcombining final bit group with inital one\n");
         BitGroups[BitGroups.size()-1].EndIdx = BitGroups[0].EndIdx;
         BitGroups.erase(BitGroups.begin());
       }
@@ -781,9 +963,11 @@ class BitPermutationSelector {
     ValueRots.clear();
 
     for (auto &BG : BitGroups) {
-      ValueRotInfo &VRI = ValueRots[std::make_pair(BG.V, BG.RLAmt)];
+      unsigned RLAmtKey = BG.RLAmt + (BG.Repl32 ? 64 : 0);
+      ValueRotInfo &VRI = ValueRots[std::make_pair(BG.V, RLAmtKey)];
       VRI.V = BG.V;
       VRI.RLAmt = BG.RLAmt;
+      VRI.Repl32 = BG.Repl32;
       VRI.NumGroups += 1;
       VRI.FirstGroupStartIdx = std::min(VRI.FirstGroupStartIdx, BG.StartIdx);
     }
@@ -797,15 +981,164 @@ class BitPermutationSelector {
     std::sort(ValueRotsVec.begin(), ValueRotsVec.end());
   }
 
+  // In 64-bit mode, rlwinm and friends have a rotation operator that
+  // replicates the low-order 32 bits into the high-order 32-bits. The mask
+  // indices of these instructions can only be in the lower 32 bits, so they
+  // can only represent some 64-bit bit groups. However, when they can be used,
+  // the 32-bit replication can be used to represent, as a single bit group,
+  // otherwise separate bit groups. We'll convert to replicated-32-bit bit
+  // groups when possible. Returns true if any of the bit groups were
+  // converted.
+  void assignRepl32BitGroups() {
+    // If we have bits like this:
+    //
+    // Indices:    15 14 13 12 11 10 9 8  7  6  5  4  3  2  1  0
+    // V bits: ... 7  6  5  4  3  2  1 0 31 30 29 28 27 26 25 24
+    // Groups:    |      RLAmt = 8      |      RLAmt = 40       |
+    //
+    // But, making use of a 32-bit operation that replicates the low-order 32
+    // bits into the high-order 32 bits, this can be one bit group with a RLAmt
+    // of 8.
+
+    auto IsAllLow32 = [this](BitGroup & BG) {
+      if (BG.StartIdx <= BG.EndIdx) {
+        for (unsigned i = BG.StartIdx; i <= BG.EndIdx; ++i) {
+          if (!Bits[i].hasValue())
+            continue;
+          if (Bits[i].getValueBitIndex() >= 32)
+            return false;
+        }
+      } else {
+        for (unsigned i = BG.StartIdx; i < Bits.size(); ++i) {
+          if (!Bits[i].hasValue())
+            continue;
+          if (Bits[i].getValueBitIndex() >= 32)
+            return false;
+        }
+        for (unsigned i = 0; i <= BG.EndIdx; ++i) {
+          if (!Bits[i].hasValue())
+            continue;
+          if (Bits[i].getValueBitIndex() >= 32)
+            return false;
+        }
+      }
+
+      return true;
+    };
+
+    for (auto &BG : BitGroups) {
+      if (BG.StartIdx < 32 && BG.EndIdx < 32) {
+        if (IsAllLow32(BG)) {
+          if (BG.RLAmt >= 32) {
+            BG.RLAmt -= 32;
+            BG.Repl32CR = true;
+          }
+
+          BG.Repl32 = true;
+
+          DEBUG(dbgs() << "\t32-bit replicated bit group for " <<
+                          BG.V.getNode() << " RLAmt = " << BG.RLAmt <<
+                          " [" << BG.StartIdx << ", " << BG.EndIdx << "]\n");
+        }
+      }
+    }
+
+    // Now walk through the bit groups, consolidating where possible.
+    for (auto I = BitGroups.begin(); I != BitGroups.end();) {
+      // We might want to remove this bit group by merging it with the previous
+      // group (which might be the ending group).
+      auto IP = (I == BitGroups.begin()) ?
+                std::prev(BitGroups.end()) : std::prev(I);
+      if (I->Repl32 && IP->Repl32 && I->V == IP->V && I->RLAmt == IP->RLAmt &&
+          I->StartIdx == (IP->EndIdx + 1) % 64 && I != IP) {
+
+        DEBUG(dbgs() << "\tcombining 32-bit replicated bit group for " <<
+                        I->V.getNode() << " RLAmt = " << I->RLAmt <<
+                        " [" << I->StartIdx << ", " << I->EndIdx <<
+                        "] with group with range [" <<
+                        IP->StartIdx << ", " << IP->EndIdx << "]\n");
+
+        IP->EndIdx = I->EndIdx;
+        IP->Repl32CR = IP->Repl32CR || I->Repl32CR;
+        IP->Repl32Coalesced = true;
+        I = BitGroups.erase(I);
+        continue;
+      } else {
+        // There is a special case worth handling: If there is a single group
+        // covering the entire upper 32 bits, and it can be merged with both
+        // the next and previous groups (which might be the same group), then
+        // do so. If it is the same group (so there will be only one group in
+        // total), then we need to reverse the order of the range so that it
+        // covers the entire 64 bits.
+        if (I->StartIdx == 32 && I->EndIdx == 63) {
+          assert(std::next(I) == BitGroups.end() &&
+                 "bit group ends at index 63 but there is another?");
+          auto IN = BitGroups.begin();
+
+          if (IP->Repl32 && IN->Repl32 && I->V == IP->V && I->V == IN->V && 
+              (I->RLAmt % 32) == IP->RLAmt && (I->RLAmt % 32) == IN->RLAmt &&
+              IP->EndIdx == 31 && IN->StartIdx == 0 && I != IP &&
+              IsAllLow32(*I)) {
+
+            DEBUG(dbgs() << "\tcombining bit group for " <<
+                            I->V.getNode() << " RLAmt = " << I->RLAmt <<
+                            " [" << I->StartIdx << ", " << I->EndIdx <<
+                            "] with 32-bit replicated groups with ranges [" <<
+                            IP->StartIdx << ", " << IP->EndIdx << "] and [" <<
+                            IN->StartIdx << ", " << IN->EndIdx << "]\n");
+
+            if (IP == IN) {
+              // There is only one other group; change it to cover the whole
+              // range (backward, so that it can still be Repl32 but cover the
+              // whole 64-bit range).
+              IP->StartIdx = 31;
+              IP->EndIdx = 30;
+              IP->Repl32CR = IP->Repl32CR || I->RLAmt >= 32;
+              IP->Repl32Coalesced = true;
+              I = BitGroups.erase(I);
+            } else {
+              // There are two separate groups, one before this group and one
+              // after us (at the beginning). We're going to remove this group,
+              // but also the group at the very beginning.
+              IP->EndIdx = IN->EndIdx;
+              IP->Repl32CR = IP->Repl32CR || IN->Repl32CR || I->RLAmt >= 32;
+              IP->Repl32Coalesced = true;
+              I = BitGroups.erase(I);
+              BitGroups.erase(BitGroups.begin());
+            }
+
+            // This must be the last group in the vector (and we might have
+            // just invalidated the iterator above), so break here.
+            break;
+          }
+        }
+      }
+
+      ++I;
+    }
+  }
+
   SDValue getI32Imm(unsigned Imm) {
     return CurDAG->getTargetConstant(Imm, MVT::i32);
   }
 
+  uint64_t getZerosMask() {
+    uint64_t Mask = 0;
+    for (unsigned i = 0; i < Bits.size(); ++i) {
+      if (Bits[i].hasValue())
+        continue;
+      Mask |= (1ul << i);
+    }
+
+    return ~Mask;
+  }
+
   // Depending on the number of groups for a particular value, it might be
   // better to rotate, mask explicitly (using andi/andis), and then or the
   // result. Select this part of the result first.
-  void SelectAndParts32(SDNode *N, SDValue &Res) {
-    SDLoc dl(N);
+  void SelectAndParts32(SDLoc dl, SDValue &Res, unsigned *InstCnt) {
+    if (BPermRewriterNoMasking)
+      return;
 
     for (ValueRotInfo &VRI : ValueRotsVec) {
       unsigned Mask = 0;
@@ -842,9 +1175,19 @@ class BitPermutationSelector {
                              (unsigned) (ANDISMask != 0) +
                              (unsigned) (ANDIMask != 0 && ANDISMask != 0) +
                              (unsigned) (bool) Res;
+
+      DEBUG(dbgs() << "\t\trotation groups for " << VRI.V.getNode() <<
+                      " RL: " << VRI.RLAmt << ":" <<
+                      "\n\t\t\tisel using masking: " << NumAndInsts <<
+                      " using rotates: " << VRI.NumGroups << "\n");
+
       if (NumAndInsts >= VRI.NumGroups)
         continue;
 
+      DEBUG(dbgs() << "\t\t\t\tusing masking\n");
+
+      if (InstCnt) *InstCnt += NumAndInsts;
+
       SDValue VRot;
       if (VRI.RLAmt) {
         SDValue Ops[] =
@@ -890,19 +1233,22 @@ class BitPermutationSelector {
   }
 
   // Instruction selection for the 32-bit case.
-  SDNode *Select32(SDNode *N) {
+  SDNode *Select32(SDNode *N, bool LateMask, unsigned *InstCnt) {
     SDLoc dl(N);
     SDValue Res;
 
+    if (InstCnt) *InstCnt = 0;
+
     // Take care of cases that should use andi/andis first.
-    SelectAndParts32(N, Res);
+    SelectAndParts32(dl, Res, InstCnt);
 
     // If we've not yet selected a 'starting' instruction, and we have no zeros
     // to fill in, select the (Value, RLAmt) with the highest priority (largest
     // number of groups), and start with this rotated value.
-    if (!HasZeros && !Res) {
+    if ((!HasZeros || LateMask) && !Res) {
       ValueRotInfo &VRI = ValueRotsVec[0];
       if (VRI.RLAmt) {
+        if (InstCnt) *InstCnt += 1;
         SDValue Ops[] =
           { VRI.V, getI32Imm(VRI.RLAmt), getI32Imm(0), getI32Imm(31) };
         Res = SDValue(CurDAG->getMachineNode(PPC::RLWINM, dl, MVT::i32, Ops), 0);
@@ -919,9 +1265,11 @@ class BitPermutationSelector {
       }
     }
 
+    if (InstCnt) *InstCnt += BitGroups.size();
+
     // Insert the other groups (one at a time).
     for (auto &BG : BitGroups) {
-      if (!Res.getNode()) {
+      if (!Res) {
         SDValue Ops[] =
           { BG.V, getI32Imm(BG.RLAmt), getI32Imm(Bits.size() - BG.EndIdx - 1),
             getI32Imm(Bits.size() - BG.StartIdx - 1) };
@@ -934,9 +1282,488 @@ class BitPermutationSelector {
       }
     }
 
+    if (LateMask) {
+      unsigned Mask = (unsigned) getZerosMask();
+
+      unsigned ANDIMask = (Mask & UINT16_MAX), ANDISMask = Mask >> 16;
+      assert((ANDIMask != 0 || ANDISMask != 0) &&
+             "No set bits in zeros mask?");
+
+      if (InstCnt) *InstCnt += (unsigned) (ANDIMask != 0) +
+                               (unsigned) (ANDISMask != 0) +
+                               (unsigned) (ANDIMask != 0 && ANDISMask != 0);
+
+      SDValue ANDIVal, ANDISVal;
+      if (ANDIMask != 0)
+        ANDIVal = SDValue(CurDAG->getMachineNode(PPC::ANDIo, dl, MVT::i32,
+                            Res, getI32Imm(ANDIMask)), 0);
+      if (ANDISMask != 0)
+        ANDISVal = SDValue(CurDAG->getMachineNode(PPC::ANDISo, dl, MVT::i32,
+                             Res, getI32Imm(ANDISMask)), 0);
+
+      if (!ANDIVal)
+        Res = ANDISVal;
+      else if (!ANDISVal)
+        Res = ANDIVal;
+      else
+        Res = SDValue(CurDAG->getMachineNode(PPC::OR, dl, MVT::i32,
+                        ANDIVal, ANDISVal), 0);
+    }
+
     return Res.getNode();
   }
 
+  unsigned SelectRotMask64Count(unsigned RLAmt, bool Repl32,
+                                unsigned MaskStart, unsigned MaskEnd,
+                                bool IsIns) {
+    // In the notation used by the instructions, 'start' and 'end' are reversed
+    // because bits are counted from high to low order.
+    unsigned InstMaskStart = 64 - MaskEnd - 1,
+             InstMaskEnd   = 64 - MaskStart - 1;
+
+    if (Repl32)
+      return 1;
+
+    if ((!IsIns && (InstMaskEnd == 63 || InstMaskStart == 0)) ||
+        InstMaskEnd == 63 - RLAmt)
+      return 1;
+
+    return 2;
+  }
+
+  // For 64-bit values, not all combinations of rotates and masks are
+  // available. Produce one if it is available.
+  SDValue SelectRotMask64(SDValue V, SDLoc dl, unsigned RLAmt, bool Repl32,
+                          unsigned MaskStart, unsigned MaskEnd,
+                          unsigned *InstCnt = nullptr) {
+    // In the notation used by the instructions, 'start' and 'end' are reversed
+    // because bits are counted from high to low order.
+    unsigned InstMaskStart = 64 - MaskEnd - 1,
+             InstMaskEnd   = 64 - MaskStart - 1;
+
+    if (InstCnt) *InstCnt += 1;
+
+    if (Repl32) {
+      // This rotation amount assumes that the lower 32 bits of the quantity
+      // are replicated in the high 32 bits by the rotation operator (which is
+      // done by rlwinm and friends).
+      assert(InstMaskStart >= 32 && "Mask cannot start out of range");
+      assert(InstMaskEnd   >= 32 && "Mask cannot end out of range");
+      SDValue Ops[] =
+        { V, getI32Imm(RLAmt), getI32Imm(InstMaskStart - 32),
+          getI32Imm(InstMaskEnd - 32) };
+      return SDValue(CurDAG->getMachineNode(PPC::RLWINM8, dl, MVT::i64,
+                                            Ops), 0);
+    }
+
+    if (InstMaskEnd == 63) {
+      SDValue Ops[] =
+        { V, getI32Imm(RLAmt), getI32Imm(InstMaskStart) };
+      return SDValue(CurDAG->getMachineNode(PPC::RLDICL, dl, MVT::i64, Ops), 0);
+    }
+
+    if (InstMaskStart == 0) {
+      SDValue Ops[] =
+        { V, getI32Imm(RLAmt), getI32Imm(InstMaskEnd) };
+      return SDValue(CurDAG->getMachineNode(PPC::RLDICR, dl, MVT::i64, Ops), 0);
+    }
+
+    if (InstMaskEnd == 63 - RLAmt) {
+      SDValue Ops[] =
+        { V, getI32Imm(RLAmt), getI32Imm(InstMaskStart) };
+      return SDValue(CurDAG->getMachineNode(PPC::RLDIC, dl, MVT::i64, Ops), 0);
+    }
+
+    // We cannot do this with a single instruction, so we'll use two. The
+    // problem is that we're not free to choose both a rotation amount and mask
+    // start and end independently. We can choose an arbitrary mask start and
+    // end, but then the rotation amount is fixed. Rotation, however, can be
+    // inverted, and so by applying an "inverse" rotation first, we can get the
+    // desired result.
+    if (InstCnt) *InstCnt += 1;
+
+    // The rotation mask for the second instruction must be MaskStart.
+    unsigned RLAmt2 = MaskStart;
+    // The first instruction must rotate V so that the overall rotation amount
+    // is RLAmt.
+    unsigned RLAmt1 = (64 + RLAmt - RLAmt2) % 64;
+    if (RLAmt1)
+      V = SelectRotMask64(V, dl, RLAmt1, false, 0, 63);
+    return SelectRotMask64(V, dl, RLAmt2, false, MaskStart, MaskEnd);
+  }
+
+  // For 64-bit values, not all combinations of rotates and masks are
+  // available. Produce a rotate-mask-and-insert if one is available.
+  SDValue SelectRotMaskIns64(SDValue Base, SDValue V, SDLoc dl, unsigned RLAmt,
+                             bool Repl32, unsigned MaskStart,
+                             unsigned MaskEnd, unsigned *InstCnt = nullptr) {
+    // In the notation used by the instructions, 'start' and 'end' are reversed
+    // because bits are counted from high to low order.
+    unsigned InstMaskStart = 64 - MaskEnd - 1,
+             InstMaskEnd   = 64 - MaskStart - 1;
+
+    if (InstCnt) *InstCnt += 1;
+
+    if (Repl32) {
+      // This rotation amount assumes that the lower 32 bits of the quantity
+      // are replicated in the high 32 bits by the rotation operator (which is
+      // done by rlwinm and friends).
+      assert(InstMaskStart >= 32 && "Mask cannot start out of range");
+      assert(InstMaskEnd   >= 32 && "Mask cannot end out of range");
+      SDValue Ops[] =
+        { Base, V, getI32Imm(RLAmt), getI32Imm(InstMaskStart - 32),
+          getI32Imm(InstMaskEnd - 32) };
+      return SDValue(CurDAG->getMachineNode(PPC::RLWIMI8, dl, MVT::i64,
+                                            Ops), 0);
+    }
+
+    if (InstMaskEnd == 63 - RLAmt) {
+      SDValue Ops[] =
+        { Base, V, getI32Imm(RLAmt), getI32Imm(InstMaskStart) };
+      return SDValue(CurDAG->getMachineNode(PPC::RLDIMI, dl, MVT::i64, Ops), 0);
+    }
+
+    // We cannot do this with a single instruction, so we'll use two. The
+    // problem is that we're not free to choose both a rotation amount and mask
+    // start and end independently. We can choose an arbitrary mask start and
+    // end, but then the rotation amount is fixed. Rotation, however, can be
+    // inverted, and so by applying an "inverse" rotation first, we can get the
+    // desired result.
+    if (InstCnt) *InstCnt += 1;
+
+    // The rotation mask for the second instruction must be MaskStart.
+    unsigned RLAmt2 = MaskStart;
+    // The first instruction must rotate V so that the overall rotation amount
+    // is RLAmt.
+    unsigned RLAmt1 = (64 + RLAmt - RLAmt2) % 64;
+    if (RLAmt1)
+      V = SelectRotMask64(V, dl, RLAmt1, false, 0, 63);
+    return SelectRotMaskIns64(Base, V, dl, RLAmt2, false, MaskStart, MaskEnd);
+  }
+
+  void SelectAndParts64(SDLoc dl, SDValue &Res, unsigned *InstCnt) {
+    if (BPermRewriterNoMasking)
+      return;
+
+    // The idea here is the same as in the 32-bit version, but with additional
+    // complications from the fact that Repl32 might be true. Because we
+    // aggressively convert bit groups to Repl32 form (which, for small
+    // rotation factors, involves no other change), and then coalesce, it might
+    // be the case that a single 64-bit masking operation could handle both
+    // some Repl32 groups and some non-Repl32 groups. If converting to Repl32
+    // form allowed coalescing, then we must use a 32-bit rotaton in order to
+    // completely capture the new combined bit group.
+
+    for (ValueRotInfo &VRI : ValueRotsVec) {
+      uint64_t Mask = 0;
+
+      // We need to add to the mask all bits from the associated bit groups.
+      // If Repl32 is false, we need to add bits from bit groups that have
+      // Repl32 true, but are trivially convertable to Repl32 false. Such a
+      // group is trivially convertable if it overlaps only with the lower 32
+      // bits, and the group has not been coalesced.
+      auto MatchingBG = [VRI](BitGroup &BG) {
+        if (VRI.V != BG.V)
+          return false;
+
+        unsigned EffRLAmt = BG.RLAmt;
+        if (!VRI.Repl32 && BG.Repl32) {
+          if (BG.StartIdx < 32 && BG.EndIdx < 32 && BG.StartIdx <= BG.EndIdx &&
+              !BG.Repl32Coalesced) {
+            if (BG.Repl32CR)
+              EffRLAmt += 32;
+          } else {
+            return false;
+          }
+        } else if (VRI.Repl32 != BG.Repl32) {
+          return false;
+        }
+
+        if (VRI.RLAmt != EffRLAmt)
+          return false;
+
+        return true;
+      };
+
+      for (auto &BG : BitGroups) {
+        if (!MatchingBG(BG))
+          continue;
+
+        if (BG.StartIdx <= BG.EndIdx) {
+          for (unsigned i = BG.StartIdx; i <= BG.EndIdx; ++i)
+            Mask |= (1ul << i);
+        } else {
+          for (unsigned i = BG.StartIdx; i < Bits.size(); ++i)
+            Mask |= (1ul << i);
+          for (unsigned i = 0; i <= BG.EndIdx; ++i)
+            Mask |= (1ul << i);
+        }
+      }
+
+      // We can use the 32-bit andi/andis technique if the mask does not
+      // require any higher-order bits. This can save an instruction compared
+      // to always using the general 64-bit technique.
+      bool Use32BitInsts = isUInt<32>(Mask);
+      // Compute the masks for andi/andis that would be necessary.
+      unsigned ANDIMask = (Mask & UINT16_MAX),
+               ANDISMask = (Mask >> 16) & UINT16_MAX;
+
+      bool NeedsRotate = VRI.RLAmt || (VRI.Repl32 && !isUInt<32>(Mask));
+
+      unsigned NumAndInsts = (unsigned) NeedsRotate +
+                             (unsigned) (bool) Res;
+      if (Use32BitInsts)
+        NumAndInsts += (unsigned) (ANDIMask != 0) + (unsigned) (ANDISMask != 0) +
+                       (unsigned) (ANDIMask != 0 && ANDISMask != 0);
+      else
+        NumAndInsts += SelectInt64Count(Mask) + /* and */ 1;
+
+      unsigned NumRLInsts = 0;
+      bool FirstBG = true;
+      for (auto &BG : BitGroups) {
+        if (!MatchingBG(BG))
+          continue;
+        NumRLInsts +=
+          SelectRotMask64Count(BG.RLAmt, BG.Repl32, BG.StartIdx, BG.EndIdx,
+                               !FirstBG);
+        FirstBG = false;
+      }
+
+      DEBUG(dbgs() << "\t\trotation groups for " << VRI.V.getNode() <<
+                      " RL: " << VRI.RLAmt << (VRI.Repl32 ? " (32):" : ":") <<
+                      "\n\t\t\tisel using masking: " << NumAndInsts <<
+                      " using rotates: " << NumRLInsts << "\n");
+
+      // When we'd use andi/andis, we bias toward using the rotates (andi only
+      // has a record form, and is cracked on POWER cores). However, when using
+      // general 64-bit constant formation, bias toward the constant form,
+      // because that exposes more opportunities for CSE.
+      if (NumAndInsts > NumRLInsts)
+        continue;
+      if (Use32BitInsts && NumAndInsts == NumRLInsts)
+        continue;
+
+      DEBUG(dbgs() << "\t\t\t\tusing masking\n");
+
+      if (InstCnt) *InstCnt += NumAndInsts;
+
+      SDValue VRot;
+      // We actually need to generate a rotation if we have a non-zero rotation
+      // factor or, in the Repl32 case, if we care about any of the
+      // higher-order replicated bits. In the latter case, we generate a mask
+      // backward so that it actually includes the entire 64 bits.
+      if (VRI.RLAmt || (VRI.Repl32 && !isUInt<32>(Mask)))
+        VRot = SelectRotMask64(VRI.V, dl, VRI.RLAmt, VRI.Repl32,
+                               VRI.Repl32 ? 31 : 0, VRI.Repl32 ? 30 : 63);
+      else
+        VRot = VRI.V;
+
+      SDValue TotalVal;
+      if (Use32BitInsts) {
+        assert((ANDIMask != 0 || ANDISMask != 0) &&
+               "No set bits in mask when using 32-bit ands for 64-bit value");
+
+        SDValue ANDIVal, ANDISVal;
+        if (ANDIMask != 0)
+          ANDIVal = SDValue(CurDAG->getMachineNode(PPC::ANDIo8, dl, MVT::i64,
+                              VRot, getI32Imm(ANDIMask)), 0);
+        if (ANDISMask != 0)
+          ANDISVal = SDValue(CurDAG->getMachineNode(PPC::ANDISo8, dl, MVT::i64,
+                               VRot, getI32Imm(ANDISMask)), 0);
+
+        if (!ANDIVal)
+          TotalVal = ANDISVal;
+        else if (!ANDISVal)
+          TotalVal = ANDIVal;
+        else
+          TotalVal = SDValue(CurDAG->getMachineNode(PPC::OR8, dl, MVT::i64,
+                               ANDIVal, ANDISVal), 0);
+      } else {
+        TotalVal = SDValue(SelectInt64(CurDAG, dl, Mask), 0);
+        TotalVal =
+          SDValue(CurDAG->getMachineNode(PPC::AND8, dl, MVT::i64,
+                                         VRot, TotalVal), 0);
+     }
+
+      if (!Res)
+        Res = TotalVal;
+      else
+        Res = SDValue(CurDAG->getMachineNode(PPC::OR8, dl, MVT::i64,
+                                             Res, TotalVal), 0);
+
+      // Now, remove all groups with this underlying value and rotation
+      // factor.
+      for (auto I = BitGroups.begin(); I != BitGroups.end();) {
+        if (MatchingBG(*I))
+          I = BitGroups.erase(I);
+        else
+          ++I;
+      }
+    }
+  }
+
+  // Instruction selection for the 64-bit case.
+  SDNode *Select64(SDNode *N, bool LateMask, unsigned *InstCnt) {
+    SDLoc dl(N);
+    SDValue Res;
+
+    if (InstCnt) *InstCnt = 0;
+
+    // Take care of cases that should use andi/andis first.
+    SelectAndParts64(dl, Res, InstCnt);
+
+    // If we've not yet selected a 'starting' instruction, and we have no zeros
+    // to fill in, select the (Value, RLAmt) with the highest priority (largest
+    // number of groups), and start with this rotated value.
+    if ((!HasZeros || LateMask) && !Res) {
+      // If we have both Repl32 groups and non-Repl32 groups, the non-Repl32
+      // groups will come first, and so the VRI representing the largest number
+      // of groups might not be first (it might be the first Repl32 groups).
+      unsigned MaxGroupsIdx = 0;
+      if (!ValueRotsVec[0].Repl32) {
+        for (unsigned i = 0, ie = ValueRotsVec.size(); i < ie; ++i)
+          if (ValueRotsVec[i].Repl32) {
+            if (ValueRotsVec[i].NumGroups > ValueRotsVec[0].NumGroups)
+              MaxGroupsIdx = i;
+            break;
+          }
+      }
+
+      ValueRotInfo &VRI = ValueRotsVec[MaxGroupsIdx];
+      bool NeedsRotate = false;
+      if (VRI.RLAmt) {
+        NeedsRotate = true;
+      } else if (VRI.Repl32) {
+        for (auto &BG : BitGroups) {
+          if (BG.V != VRI.V || BG.RLAmt != VRI.RLAmt ||
+              BG.Repl32 != VRI.Repl32)
+            continue;
+
+          // We don't need a rotate if the bit group is confined to the lower
+          // 32 bits.
+          if (BG.StartIdx < 32 && BG.EndIdx < 32 && BG.StartIdx < BG.EndIdx)
+            continue;
+
+          NeedsRotate = true;
+          break;
+        }
+      }
+
+      if (NeedsRotate)
+        Res = SelectRotMask64(VRI.V, dl, VRI.RLAmt, VRI.Repl32,
+                              VRI.Repl32 ? 31 : 0, VRI.Repl32 ? 30 : 63,
+                              InstCnt);
+      else
+        Res = VRI.V;
+
+      // Now, remove all groups with this underlying value and rotation factor.
+      if (Res)
+        for (auto I = BitGroups.begin(); I != BitGroups.end();) {
+          if (I->V == VRI.V && I->RLAmt == VRI.RLAmt && I->Repl32 == VRI.Repl32)
+            I = BitGroups.erase(I);
+          else
+            ++I;
+        }
+    }
+
+    // Because 64-bit rotates are more flexible than inserts, we might have a
+    // preference regarding which one we do first (to save one instruction).
+    if (!Res)
+      for (auto I = BitGroups.begin(), IE = BitGroups.end(); I != IE; ++I) {
+        if (SelectRotMask64Count(I->RLAmt, I->Repl32, I->StartIdx, I->EndIdx,
+                                false) <
+            SelectRotMask64Count(I->RLAmt, I->Repl32, I->StartIdx, I->EndIdx,
+                                true)) {
+          if (I != BitGroups.begin()) {
+            BitGroup BG = *I;
+            BitGroups.erase(I);
+            BitGroups.insert(BitGroups.begin(), BG);
+          }
+
+          break;
+        }
+      }
+
+    // Insert the other groups (one at a time).
+    for (auto &BG : BitGroups) {
+      if (!Res)
+        Res = SelectRotMask64(BG.V, dl, BG.RLAmt, BG.Repl32, BG.StartIdx,
+                              BG.EndIdx, InstCnt);
+      else
+        Res = SelectRotMaskIns64(Res, BG.V, dl, BG.RLAmt, BG.Repl32,
+                                 BG.StartIdx, BG.EndIdx, InstCnt);
+    }
+
+    if (LateMask) {
+      uint64_t Mask = getZerosMask();
+
+      // We can use the 32-bit andi/andis technique if the mask does not
+      // require any higher-order bits. This can save an instruction compared
+      // to always using the general 64-bit technique.
+      bool Use32BitInsts = isUInt<32>(Mask);
+      // Compute the masks for andi/andis that would be necessary.
+      unsigned ANDIMask = (Mask & UINT16_MAX),
+               ANDISMask = (Mask >> 16) & UINT16_MAX;
+
+      if (Use32BitInsts) {
+        assert((ANDIMask != 0 || ANDISMask != 0) &&
+               "No set bits in mask when using 32-bit ands for 64-bit value");
+
+        if (InstCnt) *InstCnt += (unsigned) (ANDIMask != 0) +
+                                 (unsigned) (ANDISMask != 0) +
+                                 (unsigned) (ANDIMask != 0 && ANDISMask != 0);
+
+        SDValue ANDIVal, ANDISVal;
+        if (ANDIMask != 0)
+          ANDIVal = SDValue(CurDAG->getMachineNode(PPC::ANDIo8, dl, MVT::i64,
+                              Res, getI32Imm(ANDIMask)), 0);
+        if (ANDISMask != 0)
+          ANDISVal = SDValue(CurDAG->getMachineNode(PPC::ANDISo8, dl, MVT::i64,
+                               Res, getI32Imm(ANDISMask)), 0);
+
+        if (!ANDIVal)
+          Res = ANDISVal;
+        else if (!ANDISVal)
+          Res = ANDIVal;
+        else
+          Res = SDValue(CurDAG->getMachineNode(PPC::OR8, dl, MVT::i64,
+                          ANDIVal, ANDISVal), 0);
+      } else {
+        if (InstCnt) *InstCnt += SelectInt64Count(Mask) + /* and */ 1;
+
+        SDValue MaskVal = SDValue(SelectInt64(CurDAG, dl, Mask), 0);
+        Res =
+          SDValue(CurDAG->getMachineNode(PPC::AND8, dl, MVT::i64,
+                                         Res, MaskVal), 0);
+      }
+    }
+
+    return Res.getNode();
+  }
+
+  SDNode *Select(SDNode *N, bool LateMask, unsigned *InstCnt = nullptr) {
+    // Fill in BitGroups.
+    collectBitGroups(LateMask);
+    if (BitGroups.empty())
+      return nullptr;
+
+    // For 64-bit values, figure out when we can use 32-bit instructions.
+    if (Bits.size() == 64)
+      assignRepl32BitGroups();
+
+    // Fill in ValueRotsVec.
+    collectValueRotInfo();
+
+    if (Bits.size() == 32) {
+      return Select32(N, LateMask, InstCnt);
+    } else {
+      assert(Bits.size() == 64 && "Not 64 bits here?");
+      return Select64(N, LateMask, InstCnt);
+    }
+
+    return nullptr;
+  }
+
   SmallVector<ValueBit, 64> Bits;
 
   bool HasZeros;
@@ -968,22 +1795,34 @@ public:
     // Fill it RLAmt and set HasZeros.
     computeRotationAmounts();
 
-    // Fill in BitGroups.
-    collectBitGroups();
-    if (BitGroups.empty())
-      return nullptr;
-
-    // Fill in ValueRotsVec.
-    collectValueRotInfo();
+    if (!HasZeros)
+      return Select(N, false);
 
-    if (Bits.size() == 32) {
-      return Select32(N);
-    } else {
-      assert(Bits.size() == 64 && "Not 64 bits here?");
-      // TODO: The 64-bit case!
+    // We currently have two techniques for handling results with zeros: early
+    // masking (the default) and late masking. Late masking is sometimes more
+    // efficient, but because the structure of the bit groups is different, it
+    // is hard to tell without generating both and comparing the results. With
+    // late masking, we ignore zeros in the resulting value when inserting each
+    // set of bit groups, and then mask in the zeros at the end. With early
+    // masking, we only insert the non-zero parts of the result at every step.
+
+    unsigned InstCnt, InstCntLateMask;
+    DEBUG(dbgs() << "\tEarly masking:\n");
+    SDNode *RN = Select(N, false, &InstCnt);
+    DEBUG(dbgs() << "\t\tisel would use " << InstCnt << " instructions\n");
+
+    DEBUG(dbgs() << "\tLate masking:\n");
+    SDNode *RNLM = Select(N, true, &InstCntLateMask);
+    DEBUG(dbgs() << "\t\tisel would use " << InstCntLateMask <<
+                    " instructions\n");
+
+    if (InstCnt <= InstCntLateMask) {
+      DEBUG(dbgs() << "\tUsing early-masking for isel\n");
+      return RN;
     }
 
-    return nullptr;
+    DEBUG(dbgs() << "\tUsing late-masking for isel\n");
+    return RNLM;
   }
 };
 } // anonymous namespace
@@ -993,6 +1832,9 @@ SDNode *PPCDAGToDAGISel::SelectBitPermut
       N->getValueType(0) != MVT::i64)
     return nullptr;
 
+  if (!UseBitPermRewriter)
+    return nullptr;
+
   switch (N->getOpcode()) {
   default: break;
   case ISD::ROTL:
@@ -1431,77 +2273,8 @@ SDNode *PPCDAGToDAGISel::Select(SDNode *
   default: break;
 
   case ISD::Constant: {
-    if (N->getValueType(0) == MVT::i64) {
-      // Get 64 bit value.
-      int64_t Imm = cast<ConstantSDNode>(N)->getZExtValue();
-      // Assume no remaining bits.
-      unsigned Remainder = 0;
-      // Assume no shift required.
-      unsigned Shift = 0;
-
-      // If it can't be represented as a 32 bit value.
-      if (!isInt<32>(Imm)) {
-        Shift = countTrailingZeros<uint64_t>(Imm);
-        int64_t ImmSh = static_cast<uint64_t>(Imm) >> Shift;
-
-        // If the shifted value fits 32 bits.
-        if (isInt<32>(ImmSh)) {
-          // Go with the shifted value.
-          Imm = ImmSh;
-        } else {
-          // Still stuck with a 64 bit value.
-          Remainder = Imm;
-          Shift = 32;
-          Imm >>= 32;
-        }
-      }
-
-      // Intermediate operand.
-      SDNode *Result;
-
-      // Handle first 32 bits.
-      unsigned Lo = Imm & 0xFFFF;
-      unsigned Hi = (Imm >> 16) & 0xFFFF;
-
-      // Simple value.
-      if (isInt<16>(Imm)) {
-       // Just the Lo bits.
-        Result = CurDAG->getMachineNode(PPC::LI8, dl, MVT::i64, getI32Imm(Lo));
-      } else if (Lo) {
-        // Handle the Hi bits.
-        unsigned OpC = Hi ? PPC::LIS8 : PPC::LI8;
-        Result = CurDAG->getMachineNode(OpC, dl, MVT::i64, getI32Imm(Hi));
-        // And Lo bits.
-        Result = CurDAG->getMachineNode(PPC::ORI8, dl, MVT::i64,
-                                        SDValue(Result, 0), getI32Imm(Lo));
-      } else {
-       // Just the Hi bits.
-        Result = CurDAG->getMachineNode(PPC::LIS8, dl, MVT::i64, getI32Imm(Hi));
-      }
-
-      // If no shift, we're done.
-      if (!Shift) return Result;
-
-      // Shift for next step if the upper 32-bits were not zero.
-      if (Imm) {
-        Result = CurDAG->getMachineNode(PPC::RLDICR, dl, MVT::i64,
-                                        SDValue(Result, 0),
-                                        getI32Imm(Shift),
-                                        getI32Imm(63 - Shift));
-      }
-
-      // Add in the last bits as required.
-      if ((Hi = (Remainder >> 16) & 0xFFFF)) {
-        Result = CurDAG->getMachineNode(PPC::ORIS8, dl, MVT::i64,
-                                        SDValue(Result, 0), getI32Imm(Hi));
-      }
-      if ((Lo = Remainder & 0xFFFF)) {
-        Result = CurDAG->getMachineNode(PPC::ORI8, dl, MVT::i64,
-                                        SDValue(Result, 0), getI32Imm(Lo));
-      }
-
-      return Result;
-    }
+    if (N->getValueType(0) == MVT::i64)
+      return SelectInt64(CurDAG, N);
     break;
   }
 

Modified: llvm/trunk/lib/Target/PowerPC/PPCInstr64Bit.td
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/PowerPC/PPCInstr64Bit.td?rev=225056&r1=225055&r2=225056&view=diff
==============================================================================
--- llvm/trunk/lib/Target/PowerPC/PPCInstr64Bit.td (original)
+++ llvm/trunk/lib/Target/PowerPC/PPCInstr64Bit.td Wed Dec 31 20:53:29 2014
@@ -617,13 +617,11 @@ def MULLI8 : DForm_2<7, (outs g8rc:$rD),
 }
 
 let hasSideEffects = 0 in {
-let isCommutable = 1 in {
 defm RLDIMI : MDForm_1r<30, 3, (outs g8rc:$rA),
                         (ins g8rc:$rSi, g8rc:$rS, u6imm:$SH, u6imm:$MBE),
                         "rldimi", "$rA, $rS, $SH, $MBE", IIC_IntRotateDI,
                         []>, isPPC64, RegConstraint<"$rSi = $rA">,
                         NoEncode<"$rSi">;
-}
 
 // Rotate instructions.
 defm RLDCL  : MDSForm_1r<30, 8,

Modified: llvm/trunk/test/CodeGen/PowerPC/bperm.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/PowerPC/bperm.ll?rev=225056&r1=225055&r2=225056&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/PowerPC/bperm.ll (original)
+++ llvm/trunk/test/CodeGen/PowerPC/bperm.ll Wed Dec 31 20:53:29 2014
@@ -16,6 +16,100 @@ entry:
 ; CHECK: blr
 }
 
+define i64 @bs8(i64 %x) #0 {
+entry:
+  %0 = tail call i64 @llvm.bswap.i64(i64 %x)
+  ret i64 %0
+
+; CHECK-LABEL: @bs8
+; CHECK-DAG: rldicl [[REG1:[0-9]+]], 3, 16, 0
+; CHECK-DAG: rldicl [[REG2:[0-9]+]], 3, 8, 0
+; CHECK-DAG: rldicl [[REG3:[0-9]+]], 3, 24, 0
+; CHECK-DAG: rldimi [[REG2]], [[REG1]], 8, 48
+; CHECK-DAG: rldicl [[REG4:[0-9]+]], 3, 32, 0
+; CHECK-DAG: rldimi [[REG2]], [[REG3]], 16, 40
+; CHECK-DAG: rldicl [[REG5:[0-9]+]], 3, 48, 0
+; CHECK-DAG: rldimi [[REG2]], [[REG4]], 24, 32
+; CHECK-DAG: rldicl [[REG6:[0-9]+]], 3, 56, 0
+; CHECK-DAG: rldimi [[REG2]], [[REG5]], 40, 16
+; CHECK-DAG: rldimi [[REG2]], [[REG6]], 48, 8
+; CHECK-DAG: rldimi [[REG2]], 3, 56, 0
+; CHECK: mr 3, [[REG2]]
+; CHECK: blr
+}
+
+define i64 @test1(i64 %i0, i64 %i1) #0 {
+entry:
+  %0 = lshr i64 %i1, 8
+  %and = and i64 %0, 5963776000
+  ret i64 %and
+
+; CHECK-LABEL: @test1
+; CHECK-DAG: li [[REG1:[0-9]+]], 11375
+; CHECK-DAG: rldicl [[REG3:[0-9]+]], 4, 56, 0
+; CHECK-DAG: sldi [[REG2:[0-9]+]], [[REG1]], 19
+; CHECK: and 3, [[REG3]], [[REG2]]
+; CHECK: blr
+}
+
+define i64 @test2(i64 %i0, i64 %i1) #0 {
+entry:
+  %0 = lshr i64 %i1, 6
+  %and = and i64 %0, 133434808670355456
+  ret i64 %and
+
+; CHECK-LABEL: @test2
+; CHECK-DAG: lis [[REG1:[0-9]+]], 474
+; CHECK-DAG: rldicl [[REG5:[0-9]+]], 4, 58, 0
+; CHECK-DAG: ori [[REG2:[0-9]+]], [[REG1]], 3648
+; CHECK-DAG: sldi [[REG3:[0-9]+]], [[REG2]], 32
+; CHECK-DAG: oris [[REG4:[0-9]+]], [[REG3]], 25464
+; CHECK: and 3, [[REG5]], [[REG4]]
+; CHECK: blr
+}
+
+define i64 @test3(i64 %i0, i64 %i1) #0 {
+entry:
+  %0 = shl i64 %i0, 34
+  %and = and i64 %0, 191795733152661504
+  ret i64 %and
+
+; CHECK-LABEL: @test3
+; CHECK-DAG: lis [[REG1:[0-9]+]], 170
+; CHECK-DAG: rldicl [[REG4:[0-9]+]], 3, 34, 0
+; CHECK-DAG: ori [[REG2:[0-9]+]], [[REG1]], 22861
+; CHECK-DAG: sldi [[REG3:[0-9]+]], [[REG2]], 34
+; CHECK: and 3, [[REG4]], [[REG3]]
+; CHECK: blr
+}
+
+define i64 @test4(i64 %i0, i64 %i1) #0 {
+entry:
+  %0 = lshr i64 %i1, 15
+  %and = and i64 %0, 58195968
+  ret i64 %and
+
+; CHECK-LABEL: @test4
+; CHECK: rldicl [[REG1:[0-9]+]], 4, 49, 0
+; CHECK: andis. 3, [[REG1]], 888
+; CHECK: blr
+}
+
+define i64 @test5(i64 %i0, i64 %i1) #0 {
+entry:
+  %0 = shl i64 %i1, 12
+  %and = and i64 %0, 127252959854592
+  ret i64 %and
+
+; CHECK-LABEL: @test5
+; CHECK-DAG: lis [[REG1:[0-9]+]], 3703
+; CHECK-DAG: rldicl [[REG4:[0-9]+]], 4, 12, 0
+; CHECK-DAG: ori [[REG2:[0-9]+]], [[REG1]], 35951
+; CHECK-DAG: sldi [[REG3:[0-9]+]], [[REG2]], 19
+; CHECK: and 3, [[REG4]], [[REG3]]
+; CHECK: blr
+}
+
 ; Function Attrs: nounwind readnone
 define zeroext i32 @test6(i32 zeroext %x) #0 {
 entry:
@@ -33,8 +127,153 @@ entry:
 ; CHECK: blr
 }
 
+define i64 @test7(i64 %i0, i64 %i1) #0 {
+entry:
+  %0 = lshr i64 %i0, 5
+  %and = and i64 %0, 58195968
+  ret i64 %and
+
+; CHECK-LABEL: @test7
+; CHECK: rlwinm [[REG1:[0-9]+]], 3, 27, 9, 12
+; CHECK: rlwimi [[REG1]], 3, 27, 6, 7
+; CHECK: mr 3, [[REG1]]
+; CHECK: blr
+}
+
+define i64 @test8(i64 %i0, i64 %i1) #0 {
+entry:
+  %0 = lshr i64 %i0, 1
+  %and = and i64 %0, 169172533248
+  ret i64 %and
+
+; CHECK-LABEL: @test8
+; CHECK-DAG: lis [[REG1:[0-9]+]], 4
+; CHECK-DAG: rldicl [[REG4:[0-9]+]], 3, 63, 0
+; CHECK-DAG: ori [[REG2:[0-9]+]], [[REG1]], 60527
+; CHECK-DAG: sldi [[REG3:[0-9]+]], [[REG2]], 19
+; CHECK: and 3, [[REG4]], [[REG3]]
+; CHECK: blr
+}
+
+define i64 @test9(i64 %i0, i64 %i1) #0 {
+entry:
+  %0 = lshr i64 %i1, 14
+  %and = and i64 %0, 18848677888
+  %1 = shl i64 %i1, 51
+  %and3 = and i64 %1, 405323966463344640
+  %or4 = or i64 %and, %and3
+  ret i64 %or4
+
+; CHECK-LABEL: @test9
+; CHECK-DAG: lis [[REG1:[0-9]+]], 1440
+; CHECK-DAG: rldicl [[REG5:[0-9]+]], 4, 62, 0
+; CHECK-DAG: rldicl [[REG6:[0-9]+]], 4, 50, 0
+; CHECK-DAG: ori [[REG2:[0-9]+]], [[REG1]], 4
+; CHECK-DAG: rldimi [[REG6]], [[REG5]], 53, 0
+; CHECK-DAG: sldi [[REG3:[0-9]+]], [[REG2]], 32
+; CHECK-DAG: oris [[REG4:[0-9]+]], [[REG3]], 25464
+; CHECK: and 3, [[REG6]], [[REG4]]
+; CHECK: blr
+}
+
+define i64 @test10(i64 %i0, i64 %i1) #0 {
+entry:
+  %0 = shl i64 %i0, 37
+  %and = and i64 %0, 15881483390550016
+  %1 = shl i64 %i0, 25
+  %and3 = and i64 %1, 2473599172608
+  %or4 = or i64 %and, %and3
+  ret i64 %or4
+
+; CHECK-LABEL: @test10
+; CHECK-DAG: lis [[REG1:[0-9]+]], 1
+; CHECK-DAG: rldicl [[REG6:[0-9]+]], 3, 25, 0
+; CHECK-DAG: rldicl [[REG7:[0-9]+]], 3, 37, 0
+; CHECK-DAG: ori [[REG2:[0-9]+]], [[REG1]], 8183
+; CHECK-DAG: ori [[REG3:[0-9]+]], [[REG1]], 50017
+; CHECK-DAG: sldi [[REG4:[0-9]+]], [[REG2]], 25
+; CHECK-DAG: sldi [[REG5:[0-9]+]], [[REG3]], 37
+; CHECK-DAG: and [[REG8:[0-9]+]], [[REG6]], [[REG4]]
+; CHECK-DAG: and [[REG9:[0-9]+]], [[REG7]], [[REG5]]
+; CHECK: or 3, [[REG9]], [[REG8]]
+; CHECK: blr
+}
+
+define i64 @test11(i64 %x) #0 {
+entry:
+  %and = and i64 %x, 4294967295
+  %shl = shl i64 %x, 32
+  %or = or i64 %and, %shl
+  ret i64 %or
+
+; CHECK-LABEL: @test11
+; CHECK: rlwinm 3, 3, 0, 1, 0
+; CHECK: blr
+}
+
+define i64 @test12(i64 %x) #0 {
+entry:
+  %and = and i64 %x, 4294905855
+  %shl = shl i64 %x, 32
+  %or = or i64 %and, %shl
+  ret i64 %or
+
+; CHECK-LABEL: @test12
+; CHECK: rlwinm 3, 3, 0, 20, 15
+; CHECK: blr
+}
+
+define i64 @test13(i64 %x) #0 {
+entry:
+  %shl = shl i64 %x, 4
+  %and = and i64 %shl, 240
+  %shr = lshr i64 %x, 28
+  %and1 = and i64 %shr, 15
+  %or = or i64 %and, %and1
+  ret i64 %or
+
+; CHECK-LABEL: @test13
+; CHECK: rlwinm 3, 3, 4, 24, 31
+; CHECK: blr
+}
+
+define i64 @test14(i64 %x) #0 {
+entry:
+  %shl = shl i64 %x, 4
+  %and = and i64 %shl, 240
+  %shr = lshr i64 %x, 28
+  %and1 = and i64 %shr, 15
+  %and2 = and i64 %x, -4294967296
+  %or = or i64 %and1, %and2
+  %or3 = or i64 %or, %and
+  ret i64 %or3
+
+; CHECK-LABEL: @test14
+; CHECK: rldicr [[REG1:[0-9]+]], 3, 0, 31
+; CHECK: rlwimi [[REG1]], 3, 4, 24, 31
+; CHECK: mr 3, [[REG1]]
+; CHECK: blr
+}
+
+define i64 @test15(i64 %x) #0 {
+entry:
+  %shl = shl i64 %x, 4
+  %and = and i64 %shl, 240
+  %shr = lshr i64 %x, 28
+  %and1 = and i64 %shr, 15
+  %and2 = and i64 %x, -256
+  %or = or i64 %and1, %and2
+  %or3 = or i64 %or, %and
+  ret i64 %or3
+
+; CHECK-LABEL: @test15
+; CHECK: rlwimi 3, 3, 4, 24, 31
+; CHECK: blr
+}
+
 ; Function Attrs: nounwind readnone
 declare i32 @llvm.bswap.i32(i32) #0
+declare i64 @llvm.bswap.i64(i64) #0
 
 attributes #0 = { nounwind readnone }
 





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