Eliminate the FP_GET_ST0/FP_SET_ST0 target-specific dag nodes, just lower to
copyfromreg/copytoreg instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48174 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index e2dc29c..179f600 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -854,28 +854,18 @@
SDOperand Flag;
// Copy the result values into the output registers.
- if (RVLocs.size() != 1 || !RVLocs[0].isRegLoc() ||
- RVLocs[0].getLocReg() != X86::ST0) {
- for (unsigned i = 0; i != RVLocs.size(); ++i) {
- CCValAssign &VA = RVLocs[i];
- assert(VA.isRegLoc() && "Can only return in registers!");
- Chain = DAG.getCopyToReg(Chain, VA.getLocReg(), Op.getOperand(i*2+1),
- Flag);
- Flag = Chain.getValue(1);
- }
- } else {
- // We need to handle a destination of ST0 specially, because it isn't really
- // a register.
- SDOperand Value = Op.getOperand(1);
+ for (unsigned i = 0; i != RVLocs.size(); ++i) {
+ CCValAssign &VA = RVLocs[i];
+ assert(VA.isRegLoc() && "Can only return in registers!");
+ SDOperand ValToCopy = Op.getOperand(i*2+1);
- // an XMM register onto the fp-stack. Do this with an FP_EXTEND to f80.
- // This will get legalized into a load/store if it can't get optimized away.
- if (isScalarFPTypeInSSEReg(RVLocs[0].getValVT()))
- Value = DAG.getNode(ISD::FP_EXTEND, MVT::f80, Value);
+ // If this is a copy from an xmm register to ST(0), use an FPExtend to
+ // change the value to the FP stack register class.
+ if (RVLocs[i].getLocReg() == X86::ST0 &&
+ isScalarFPTypeInSSEReg(RVLocs[i].getValVT()))
+ ValToCopy = DAG.getNode(ISD::FP_EXTEND, MVT::f80, ValToCopy);
- SDVTList Tys = DAG.getVTList(MVT::Other, MVT::Flag);
- SDOperand Ops[] = { Chain, Value };
- Chain = DAG.getNode(X86ISD::FP_SET_ST0, Tys, Ops, 2);
+ Chain = DAG.getCopyToReg(Chain, VA.getLocReg(), ValToCopy, Flag);
Flag = Chain.getValue(1);
}
@@ -905,37 +895,31 @@
SmallVector<SDOperand, 8> ResultVals;
// Copy all of the result registers out of their specified physreg.
- if (RVLocs.size() != 1 || RVLocs[0].getLocReg() != X86::ST0) {
- for (unsigned i = 0; i != RVLocs.size(); ++i) {
- Chain = DAG.getCopyFromReg(Chain, RVLocs[i].getLocReg(),
- RVLocs[i].getValVT(), InFlag).getValue(1);
- InFlag = Chain.getValue(2);
- ResultVals.push_back(Chain.getValue(0));
+ for (unsigned i = 0; i != RVLocs.size(); ++i) {
+ MVT::ValueType CopyVT = RVLocs[i].getValVT();
+
+ // If this is a call to a function that returns an fp value on the floating
+ // point stack, but where we prefer to use the value in xmm registers, copy
+ // it out as F80 and use a truncate to move it from fp stack reg to xmm reg.
+ if (RVLocs[i].getLocReg() == X86::ST0 &&
+ isScalarFPTypeInSSEReg(RVLocs[i].getValVT())) {
+ CopyVT = MVT::f80;
}
- } else {
- // Copies from the FP stack are special, as ST0 isn't a valid register
- // before the fp stackifier runs.
- // Copy ST0 into an RFP register with FP_GET_RESULT. If this will end up
- // in an SSE register, copy it out as F80 and do a truncate, otherwise use
- // the specified value type.
- MVT::ValueType GetResultTy = RVLocs[0].getValVT();
- if (isScalarFPTypeInSSEReg(GetResultTy))
- GetResultTy = MVT::f80;
- SDVTList Tys = DAG.getVTList(GetResultTy, MVT::Other, MVT::Flag);
- SDOperand GROps[] = { Chain, InFlag };
- SDOperand RetVal = DAG.getNode(X86ISD::FP_GET_ST0, Tys, GROps, 2);
- Chain = RetVal.getValue(1);
- InFlag = RetVal.getValue(2);
+ Chain = DAG.getCopyFromReg(Chain, RVLocs[i].getLocReg(),
+ CopyVT, InFlag).getValue(1);
+ SDOperand Val = Chain.getValue(0);
+ InFlag = Chain.getValue(2);
- // If we want the result in an SSE register, use an FP_TRUNCATE to get it
- // there.
- if (GetResultTy != RVLocs[0].getValVT())
- RetVal = DAG.getNode(ISD::FP_ROUND, RVLocs[0].getValVT(), RetVal,
- // This truncation won't change the value.
- DAG.getIntPtrConstant(1));
+ if (CopyVT != RVLocs[i].getValVT()) {
+ // Round the F80 the right size, which also moves to the appropriate xmm
+ // register.
+ Val = DAG.getNode(ISD::FP_ROUND, RVLocs[i].getValVT(), Val,
+ // This truncation won't change the value.
+ DAG.getIntPtrConstant(1));
+ }
- ResultVals.push_back(RetVal);
+ ResultVals.push_back(Val);
}
// Merge everything together with a MERGE_VALUES node.
@@ -5573,9 +5557,7 @@
case X86ISD::FP_TO_INT64_IN_MEM: return "X86ISD::FP_TO_INT64_IN_MEM";
case X86ISD::FLD: return "X86ISD::FLD";
case X86ISD::FST: return "X86ISD::FST";
- case X86ISD::FP_GET_ST0: return "X86ISD::FP_GET_ST0";
case X86ISD::FP_GET_ST0_ST1: return "X86ISD::FP_GET_ST0_ST1";
- case X86ISD::FP_SET_ST0: return "X86ISD::FP_SET_ST0";
case X86ISD::CALL: return "X86ISD::CALL";
case X86ISD::TAILCALL: return "X86ISD::TAILCALL";
case X86ISD::RDTSC_DAG: return "X86ISD::RDTSC_DAG";