Add support for expanding PPC 128 bit floats.

For this it is convenient to permit floats to
be used with EXTRACT_ELEMENT, so I tweaked
things to allow that.  I also added libcalls
for ppcf128 to i32 forms of FP_TO_XINT, since
they exist in libgcc and this case can certainly
occur (and does occur in the testsuite) - before
the i64 libcall was being used.  Also, the
XINT_TO_FP result seemed to be wrong when
the argument is an i128: the wrong fudge
factor was added (the i32 and i64 cases were
handled directly, but the i128 code fell
through to some generic softening code which
seemed to think it was i64 to f32!).  So I
fixed it by adding a fudge factor that I
found in my breakfast cereal.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52739 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 200 insertions, 4 deletions

diff --git a/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp b/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp
index d99a9bd6df..be1d45502d 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp
@@ -118,7 +118,7 @@ SDOperand DAGTypeLegalizer::SoftenFloatRes_FADD(SDNode *N) {
                                   RTLIB::ADD_F64,
                                   RTLIB::ADD_F80,
                                   RTLIB::ADD_PPCF128),
-                     NVT, Ops, 2, false/*sign irrelevant*/);
+                     NVT, Ops, 2, false);
 }
 
 SDOperand DAGTypeLegalizer::SoftenFloatRes_FCOPYSIGN(SDNode *N) {
@@ -169,7 +169,7 @@ SDOperand DAGTypeLegalizer::SoftenFloatRes_FMUL(SDNode *N) {
                                   RTLIB::MUL_F64,
                                   RTLIB::MUL_F80,
                                   RTLIB::MUL_PPCF128),
-                     NVT, Ops, 2, false/*sign irrelevant*/);
+                     NVT, Ops, 2, false);
 }
 
 SDOperand DAGTypeLegalizer::SoftenFloatRes_FSUB(SDNode *N) {
@@ -181,7 +181,7 @@ SDOperand DAGTypeLegalizer::SoftenFloatRes_FSUB(SDNode *N) {
                                   RTLIB::SUB_F64,
                                   RTLIB::SUB_F80,
                                   RTLIB::SUB_PPCF128),
-                     NVT, Ops, 2, false/*sign irrelevant*/);
+                     NVT, Ops, 2, false);
 }
 
 SDOperand DAGTypeLegalizer::SoftenFloatRes_LOAD(SDNode *N) {
@@ -547,7 +547,14 @@ void DAGTypeLegalizer::ExpandFloatResult(SDNode *N, unsigned ResNo) {
   case ISD::EXTRACT_ELEMENT:    ExpandRes_EXTRACT_ELEMENT(N, Lo, Hi); break;
   case ISD::EXTRACT_VECTOR_ELT: ExpandRes_EXTRACT_VECTOR_ELT(N, Lo, Hi); break;
 
-  case ISD::LOAD: ExpandFloatRes_LOAD(N, Lo, Hi); break;
+  case ISD::ConstantFP: ExpandFloatRes_ConstantFP(N, Lo, Hi); break;
+  case ISD::FADD:       ExpandFloatRes_FADD(N, Lo, Hi); break;
+  case ISD::FDIV:       ExpandFloatRes_FDIV(N, Lo, Hi); break;
+  case ISD::FMUL:       ExpandFloatRes_FMUL(N, Lo, Hi); break;
+  case ISD::FSUB:       ExpandFloatRes_FSUB(N, Lo, Hi); break;
+  case ISD::LOAD:       ExpandFloatRes_LOAD(N, Lo, Hi); break;
+  case ISD::SINT_TO_FP:
+  case ISD::UINT_TO_FP: ExpandFloatRes_XINT_TO_FP(N, Lo, Hi); break;
   }
 
   // If Lo/Hi is null, the sub-method took care of registering results etc.
@@ -555,6 +562,74 @@ void DAGTypeLegalizer::ExpandFloatResult(SDNode *N, unsigned ResNo) {
     SetExpandedFloat(SDOperand(N, ResNo), Lo, Hi);
 }
 
+void DAGTypeLegalizer::ExpandFloatRes_ConstantFP(SDNode *N, SDOperand &Lo,
+                                                 SDOperand &Hi) {
+  MVT NVT = TLI.getTypeToTransformTo(N->getValueType(0));
+  assert(NVT.getSizeInBits() == integerPartWidth &&
+         "Do not know how to expand this float constant!");
+  APInt C = cast<ConstantFPSDNode>(N)->getValueAPF().convertToAPInt();
+  Lo = DAG.getConstantFP(APFloat(APInt(integerPartWidth, 1,
+                                       &C.getRawData()[1])), NVT);
+  Hi = DAG.getConstantFP(APFloat(APInt(integerPartWidth, 1,
+                                       &C.getRawData()[0])), NVT);
+}
+
+void DAGTypeLegalizer::ExpandFloatRes_FADD(SDNode *N, SDOperand &Lo,
+                                           SDOperand &Hi) {
+  SDOperand Ops[2] = { N->getOperand(0), N->getOperand(1) };
+  SDOperand Call = MakeLibCall(GetFPLibCall(N->getValueType(0),
+                                            RTLIB::ADD_F32,
+                                            RTLIB::ADD_F64,
+                                            RTLIB::ADD_F80,
+                                            RTLIB::ADD_PPCF128),
+                               N->getValueType(0), Ops, 2,
+                               false);
+  assert(Call.Val->getOpcode() == ISD::BUILD_PAIR && "Call lowered wrongly!");
+  Lo = Call.getOperand(0); Hi = Call.getOperand(1);
+}
+
+void DAGTypeLegalizer::ExpandFloatRes_FDIV(SDNode *N, SDOperand &Lo,
+                                           SDOperand &Hi) {
+  SDOperand Ops[2] = { N->getOperand(0), N->getOperand(1) };
+  SDOperand Call = MakeLibCall(GetFPLibCall(N->getValueType(0),
+                                            RTLIB::DIV_F32,
+                                            RTLIB::DIV_F64,
+                                            RTLIB::DIV_F80,
+                                            RTLIB::DIV_PPCF128),
+                               N->getValueType(0), Ops, 2,
+                               false);
+  assert(Call.Val->getOpcode() == ISD::BUILD_PAIR && "Call lowered wrongly!");
+  Lo = Call.getOperand(0); Hi = Call.getOperand(1);
+}
+
+void DAGTypeLegalizer::ExpandFloatRes_FMUL(SDNode *N, SDOperand &Lo,
+                                           SDOperand &Hi) {
+  SDOperand Ops[2] = { N->getOperand(0), N->getOperand(1) };
+  SDOperand Call = MakeLibCall(GetFPLibCall(N->getValueType(0),
+                                            RTLIB::MUL_F32,
+                                            RTLIB::MUL_F64,
+                                            RTLIB::MUL_F80,
+                                            RTLIB::MUL_PPCF128),
+                               N->getValueType(0), Ops, 2,
+                               false);
+  assert(Call.Val->getOpcode() == ISD::BUILD_PAIR && "Call lowered wrongly!");
+  Lo = Call.getOperand(0); Hi = Call.getOperand(1);
+}
+
+void DAGTypeLegalizer::ExpandFloatRes_FSUB(SDNode *N, SDOperand &Lo,
+                                           SDOperand &Hi) {
+  SDOperand Ops[2] = { N->getOperand(0), N->getOperand(1) };
+  SDOperand Call = MakeLibCall(GetFPLibCall(N->getValueType(0),
+                                            RTLIB::SUB_F32,
+                                            RTLIB::SUB_F64,
+                                            RTLIB::SUB_F80,
+                                            RTLIB::SUB_PPCF128),
+                               N->getValueType(0), Ops, 2,
+                               false);
+  assert(Call.Val->getOpcode() == ISD::BUILD_PAIR && "Call lowered wrongly!");
+  Lo = Call.getOperand(0); Hi = Call.getOperand(1);
+}
+
 void DAGTypeLegalizer::ExpandFloatRes_LOAD(SDNode *N, SDOperand &Lo,
                                            SDOperand &Hi) {
   if (ISD::isNormalLoad(N)) {
@@ -587,6 +662,71 @@ void DAGTypeLegalizer::ExpandFloatRes_LOAD(SDNode *N, SDOperand &Lo,
   ReplaceValueWith(SDOperand(LD, 1), Chain);
 }
 
+void DAGTypeLegalizer::ExpandFloatRes_XINT_TO_FP(SDNode *N, SDOperand &Lo,
+                                                 SDOperand &Hi) {
+  assert(N->getValueType(0) == MVT::ppcf128 && "Unsupported XINT_TO_FP!");
+  MVT VT = N->getValueType(0);
+  MVT NVT = TLI.getTypeToTransformTo(VT);
+  SDOperand Src = N->getOperand(0);
+  MVT SrcVT = Src.getValueType();
+
+  // First do an SINT_TO_FP, whether the original was signed or unsigned.
+  if (SrcVT.bitsLE(MVT::i32)) {
+    // The integer can be represented exactly in an f64.
+    Src = DAG.getNode(ISD::SIGN_EXTEND, MVT::i32, Src);
+    Lo = DAG.getConstantFP(APFloat(APInt(NVT.getSizeInBits(), 0)), NVT);
+    Hi = DAG.getNode(ISD::SINT_TO_FP, NVT, Src);
+  } else {
+    RTLIB::Libcall LC = RTLIB::UNKNOWN_LIBCALL;
+    if (SrcVT.bitsLE(MVT::i64)) {
+      Src = DAG.getNode(ISD::SIGN_EXTEND, MVT::i64, Src);
+      LC = RTLIB::SINTTOFP_I64_PPCF128;
+    } else if (SrcVT.bitsLE(MVT::i128)) {
+      Src = DAG.getNode(ISD::SIGN_EXTEND, MVT::i128, Src);
+      LC = RTLIB::SINTTOFP_I128_PPCF128;
+    }
+    assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unsupported XINT_TO_FP!");
+
+    Hi = MakeLibCall(LC, VT, &Src, 1, true);
+    assert(Hi.Val->getOpcode() == ISD::BUILD_PAIR && "Call lowered wrongly!");
+    Lo = Hi.getOperand(0); Hi = Hi.getOperand(1);
+  }
+
+  if (N->getOpcode() == ISD::SINT_TO_FP)
+    return;
+
+  // Unsigned - fix up the SINT_TO_FP value just calculated.
+  Hi = DAG.getNode(ISD::BUILD_PAIR, VT, Lo, Hi);
+  SrcVT = Src.getValueType();
+
+  // x>=0 ? (ppcf128)(iN)x : (ppcf128)(iN)x + 2^N; N=32,64,128.
+  static const uint64_t TwoE32[]  = { 0x41f0000000000000LL, 0 };
+  static const uint64_t TwoE64[]  = { 0x43f0000000000000LL, 0 };
+  static const uint64_t TwoE128[] = { 0x47f0000000000000LL, 0 };
+  const uint64_t *Parts = 0;
+
+  switch (SrcVT.getSimpleVT()) {
+  default:
+    assert(false && "Unsupported UINT_TO_FP!");
+  case MVT::i32:
+    Parts = TwoE32;
+  case MVT::i64:
+    Parts = TwoE64;
+  case MVT::i128:
+    Parts = TwoE128;
+  }
+
+  Lo = DAG.getNode(ISD::FADD, VT, Hi,
+                   DAG.getConstantFP(APFloat(APInt(128, 2, Parts)),
+                                     MVT::ppcf128));
+  Lo = DAG.getNode(ISD::SELECT_CC, VT, Src, DAG.getConstant(0, SrcVT), Lo, Hi,
+                   DAG.getCondCode(ISD::SETLT));
+  Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, NVT, Lo,
+                   DAG.getConstant(1, TLI.getPointerTy()));
+  Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, NVT, Lo,
+                   DAG.getConstant(0, TLI.getPointerTy()));
+}
+
 
 //===----------------------------------------------------------------------===//
 //  Float Operand Expansion
@@ -622,6 +762,10 @@ bool DAGTypeLegalizer::ExpandFloatOperand(SDNode *N, unsigned OpNo) {
     case ISD::SELECT_CC: Res = ExpandFloatOp_BR_CC(N); break;
     case ISD::SETCC:     Res = ExpandFloatOp_BR_CC(N); break;
 
+    case ISD::FP_ROUND:   Res = ExpandFloatOp_FP_ROUND(N); break;
+    case ISD::FP_TO_SINT: Res = ExpandFloatOp_FP_TO_SINT(N); break;
+    case ISD::FP_TO_UINT: Res = ExpandFloatOp_FP_TO_UINT(N); break;
+
     case ISD::STORE:
       Res = ExpandFloatOp_STORE(cast<StoreSDNode>(N), OpNo);
       break;
@@ -728,6 +872,58 @@ SDOperand DAGTypeLegalizer::ExpandFloatOp_SETCC(SDNode *N) {
                                 DAG.getCondCode(CCCode));
 }
 
+SDOperand DAGTypeLegalizer::ExpandFloatOp_FP_TO_UINT(SDNode *N) {
+  assert(N->getOperand(0).getValueType() == MVT::ppcf128 &&
+         "Unsupported FP_TO_UINT!");
+
+  RTLIB::Libcall LC = RTLIB::UNKNOWN_LIBCALL;
+  switch (N->getValueType(0).getSimpleVT()) {
+  default:
+    assert(false && "Unsupported FP_TO_UINT!");
+  case MVT::i32:
+    LC = RTLIB::FPTOUINT_PPCF128_I32;
+    break;
+  case MVT::i64:
+    LC = RTLIB::FPTOUINT_PPCF128_I64;
+    break;
+  case MVT::i128:
+    LC = RTLIB::FPTOUINT_PPCF128_I128;
+    break;
+  }
+
+  return MakeLibCall(LC, N->getValueType(0), &N->getOperand(0), 1, false);
+}
+
+SDOperand DAGTypeLegalizer::ExpandFloatOp_FP_TO_SINT(SDNode *N) {
+  assert(N->getOperand(0).getValueType() == MVT::ppcf128 &&
+         "Unsupported FP_TO_SINT!");
+
+  RTLIB::Libcall LC = RTLIB::UNKNOWN_LIBCALL;
+  switch (N->getValueType(0).getSimpleVT()) {
+  default:
+    assert(false && "Unsupported FP_TO_SINT!");
+  case MVT::i32:
+    LC = RTLIB::FPTOSINT_PPCF128_I32;
+  case MVT::i64:
+    LC = RTLIB::FPTOSINT_PPCF128_I64;
+    break;
+  case MVT::i128:
+    LC = RTLIB::FPTOSINT_PPCF128_I64;
+    break;
+  }
+
+  return MakeLibCall(LC, N->getValueType(0), &N->getOperand(0), 1, false);
+}
+
+SDOperand DAGTypeLegalizer::ExpandFloatOp_FP_ROUND(SDNode *N) {
+  assert(N->getOperand(0).getValueType() == MVT::ppcf128 &&
+         "Logic only correct for ppcf128!");
+  SDOperand Lo, Hi;
+  GetExpandedFloat(N->getOperand(0), Lo, Hi);
+  // Round it the rest of the way (e.g. to f32) if needed.
+  return DAG.getNode(ISD::FP_ROUND, N->getValueType(0), Hi, N->getOperand(1));
+}
+
 SDOperand DAGTypeLegalizer::ExpandFloatOp_STORE(SDNode *N, unsigned OpNo) {
   if (ISD::isNormalStore(N))
     return ExpandOp_NormalStore(N, OpNo);