Next PPC long double bits: ppcf128->i32 conversion.
Surprisingly complicated.
Adds getTargetNode for 2 outputs, no inputs (missing).
llvm-svn: 42822
diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
index 20ec3c3..4a20665 100644
--- a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -76,6 +76,9 @@
// Shortening conversions involving ppcf128 get expanded (2 regs -> 1 reg)
setConvertAction(MVT::ppcf128, MVT::f64, Expand);
setConvertAction(MVT::ppcf128, MVT::f32, Expand);
+ // This is used in the ppcf128->int sequence. Note it has different semantics
+ // from FP_ROUND: that rounds to nearest, this rounds to zero.
+ setOperationAction(ISD::FP_ROUND_INREG, MVT::ppcf128, Custom);
// PowerPC has no intrinsics for these particular operations
setOperationAction(ISD::MEMMOVE, MVT::Other, Expand);
@@ -2079,6 +2082,64 @@
return Bits;
}
+static SDOperand LowerFP_ROUND_INREG(SDOperand Op, SelectionDAG &DAG) {
+ assert(Op.getValueType() == MVT::ppcf128);
+ SDNode *Node = Op.Val;
+ assert(Node->getOperand(0).getValueType() == MVT::ppcf128);
+ assert(Node->getOperand(0).Val->getOpcode()==ISD::BUILD_PAIR);
+ SDOperand Lo = Node->getOperand(0).Val->getOperand(0);
+ SDOperand Hi = Node->getOperand(0).Val->getOperand(1);
+
+ // This sequence changes FPSCR to do round-to-zero, adds the two halves
+ // of the long double, and puts FPSCR back the way it was. We do not
+ // actually model FPSCR.
+ std::vector<MVT::ValueType> NodeTys;
+ SDOperand Ops[4], Result, MFFSreg, InFlag, FPreg;
+
+ NodeTys.push_back(MVT::f64); // Return register
+ NodeTys.push_back(MVT::Flag); // Returns a flag for later insns
+ Result = DAG.getNode(PPCISD::MFFS, NodeTys, &InFlag, 0);
+ MFFSreg = Result.getValue(0);
+ InFlag = Result.getValue(1);
+
+ NodeTys.clear();
+ NodeTys.push_back(MVT::Flag); // Returns a flag
+ Ops[0] = DAG.getConstant(31, MVT::i32);
+ Ops[1] = InFlag;
+ Result = DAG.getNode(PPCISD::MTFSB1, NodeTys, Ops, 2);
+ InFlag = Result.getValue(0);
+
+ NodeTys.clear();
+ NodeTys.push_back(MVT::Flag); // Returns a flag
+ Ops[0] = DAG.getConstant(30, MVT::i32);
+ Ops[1] = InFlag;
+ Result = DAG.getNode(PPCISD::MTFSB0, NodeTys, Ops, 2);
+ InFlag = Result.getValue(0);
+
+ NodeTys.clear();
+ NodeTys.push_back(MVT::f64); // result of add
+ NodeTys.push_back(MVT::Flag); // Returns a flag
+ Ops[0] = Lo;
+ Ops[1] = Hi;
+ Ops[2] = InFlag;
+ Result = DAG.getNode(PPCISD::FADDRTZ, NodeTys, Ops, 3);
+ FPreg = Result.getValue(0);
+ InFlag = Result.getValue(1);
+
+ NodeTys.clear();
+ NodeTys.push_back(MVT::f64);
+ Ops[0] = DAG.getConstant(1, MVT::i32);
+ Ops[1] = MFFSreg;
+ Ops[2] = FPreg;
+ Ops[3] = InFlag;
+ Result = DAG.getNode(PPCISD::MTFSF, NodeTys, Ops, 4);
+ FPreg = Result.getValue(0);
+
+ // We know the low half is about to be thrown away, so just use something
+ // convenient.
+ return DAG.getNode(ISD::BUILD_PAIR, Lo.getValueType(), FPreg, FPreg);
+}
+
static SDOperand LowerSINT_TO_FP(SDOperand Op, SelectionDAG &DAG) {
if (Op.getOperand(0).getValueType() == MVT::i64) {
SDOperand Bits = DAG.getNode(ISD::BIT_CONVERT, MVT::f64, Op.getOperand(0));
@@ -2935,6 +2996,7 @@
case ISD::SELECT_CC: return LowerSELECT_CC(Op, DAG);
case ISD::FP_TO_SINT: return LowerFP_TO_SINT(Op, DAG);
case ISD::SINT_TO_FP: return LowerSINT_TO_FP(Op, DAG);
+ case ISD::FP_ROUND_INREG: return LowerFP_ROUND_INREG(Op, DAG);
// Lower 64-bit shifts.
case ISD::SHL_PARTS: return LowerSHL_PARTS(Op, DAG);
diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.h b/llvm/lib/Target/PowerPC/PPCISelLowering.h
index 33f6381..01a35a8 100644
--- a/llvm/lib/Target/PowerPC/PPCISelLowering.h
+++ b/llvm/lib/Target/PowerPC/PPCISelLowering.h
@@ -129,7 +129,28 @@
/// byte-swapping load instruction. It loads "Type" bits, byte swaps it,
/// then puts it in the bottom bits of the GPRC. TYPE can be either i16
/// or i32.
- LBRX
+ LBRX,
+
+ // The following 5 instructions are used only as part of the
+ // long double-to-int conversion sequence.
+
+ /// OUTFLAG = MFFS F8RC - This moves the FPSCR (not modelled) into the
+ /// register.
+ MFFS,
+
+ /// OUTFLAG = MTFSB0 INFLAG - This clears a bit in the FPSCR.
+ MTFSB0,
+
+ /// OUTFLAG = MTFSB1 INFLAG - This sets a bit in the FPSCR.
+ MTFSB1,
+
+ /// F8RC, OUTFLAG = FADDRTZ F8RC, F8RC, INFLAG - This is an FADD done with
+ /// rounding towards zero. It has flags added so it won't move past the
+ /// FPSCR-setting instructions.
+ FADDRTZ,
+
+ /// MTFSF = F8RC, INFLAG - This moves the register into the FPSCR.
+ MTFSF
};
}
diff --git a/llvm/lib/Target/PowerPC/PPCInstrFormats.td b/llvm/lib/Target/PowerPC/PPCInstrFormats.td
index 865320c..98e1e35 100644
--- a/llvm/lib/Target/PowerPC/PPCInstrFormats.td
+++ b/llvm/lib/Target/PowerPC/PPCInstrFormats.td
@@ -315,6 +315,34 @@
: XForm_base_r3xo<opcode, xo, OOL, IOL, asmstr, itin, pattern> {
}
+// This is used for MFFS, MTFSB0, MTFSB1. 42 is arbitrary; this series of
+// numbers presumably relates to some document, but I haven't found it.
+class XForm_42<bits<6> opcode, bits<10> xo, dag OOL, dag IOL, string asmstr,
+ InstrItinClass itin, list<dag> pattern>
+ : XForm_base_r3xo<opcode, xo, OOL, IOL, asmstr, itin, pattern> {
+ let Pattern = pattern;
+
+ bit RC = 0; // set by isDOT
+
+ let Inst{6-10} = RST;
+ let Inst{11-20} = 0;
+ let Inst{21-30} = xo;
+ let Inst{31} = RC;
+}
+class XForm_43<bits<6> opcode, bits<10> xo, dag OOL, dag IOL, string asmstr,
+ InstrItinClass itin, list<dag> pattern>
+ : XForm_base_r3xo<opcode, xo, OOL, IOL, asmstr, itin, pattern> {
+ let Pattern = pattern;
+ bits<5> FM;
+
+ bit RC = 0; // set by isDOT
+
+ let Inst{6-10} = FM;
+ let Inst{11-20} = 0;
+ let Inst{21-30} = xo;
+ let Inst{31} = RC;
+}
+
// DCB_Form - Form X instruction, used for dcb* instructions.
class DCB_Form<bits<10> xo, bits<5> immfield, dag OOL, dag IOL, string asmstr,
InstrItinClass itin, list<dag> pattern>
@@ -513,6 +541,27 @@
let SPR = spr;
}
+// XFL-Form - MTFSF
+// This is probably 1.7.9, but I don't have the reference that uses this
+// numbering scheme...
+class XFLForm<bits<6> opcode, bits<10> xo, dag OOL, dag IOL, string asmstr,
+ string cstr, InstrItinClass itin, list<dag>pattern>
+ : I<opcode, OOL, IOL, asmstr, itin> {
+ bits<8> FM;
+ bits<5> RT;
+
+ bit RC = 0; // set by isDOT
+ let Pattern = pattern;
+ let Constraints = cstr;
+
+ let Inst{6} = 0;
+ let Inst{7-14} = FM;
+ let Inst{15} = 0;
+ let Inst{16-20} = RT;
+ let Inst{21-30} = xo;
+ let Inst{31} = RC;
+}
+
// 1.7.10 XS-Form - SRADI.
class XSForm_1<bits<6> opcode, bits<9> xo, dag OOL, dag IOL, string asmstr,
InstrItinClass itin, list<dag> pattern>
diff --git a/llvm/lib/Target/PowerPC/PPCInstrInfo.td b/llvm/lib/Target/PowerPC/PPCInstrInfo.td
index 1591148..f62f7cb 100644
--- a/llvm/lib/Target/PowerPC/PPCInstrInfo.td
+++ b/llvm/lib/Target/PowerPC/PPCInstrInfo.td
@@ -53,6 +53,21 @@
def PPCfctiwz : SDNode<"PPCISD::FCTIWZ", SDTFPUnaryOp, []>;
def PPCstfiwx : SDNode<"PPCISD::STFIWX", SDT_PPCstfiwx, [SDNPHasChain]>;
+// This sequence is used for long double->int conversions. It changes the
+// bits in the FPSCR which is not modelled.
+def PPCmffs : SDNode<"PPCISD::MFFS", SDTypeProfile<1, 0, [SDTCisVT<0, f64>]>,
+ [SDNPOutFlag]>;
+def PPCmtfsb0 : SDNode<"PPCISD::MTFSB0", SDTypeProfile<0, 1, [SDTCisInt<0>]>,
+ [SDNPInFlag, SDNPOutFlag]>;
+def PPCmtfsb1 : SDNode<"PPCISD::MTFSB1", SDTypeProfile<0, 1, [SDTCisInt<0>]>,
+ [SDNPInFlag, SDNPOutFlag]>;
+def PPCfaddrtz: SDNode<"PPCISD::FADDRTZ", SDTFPBinOp,
+ [SDNPInFlag, SDNPOutFlag]>;
+def PPCmtfsf : SDNode<"PPCISD::MTFSF", SDTypeProfile<1, 3,
+ [SDTCisVT<0, f64>, SDTCisInt<1>, SDTCisVT<2, f64>,
+ SDTCisVT<3, f64>]>,
+ [SDNPInFlag]>;
+
def PPCfsel : SDNode<"PPCISD::FSEL",
// Type constraint for fsel.
SDTypeProfile<1, 3, [SDTCisSameAs<0, 2>, SDTCisSameAs<0, 3>,
@@ -873,6 +888,37 @@
"mfcr $rT, $FXM", SprMFCR>,
PPC970_DGroup_First, PPC970_Unit_CRU;
+// Instructions to manipulate FPSCR. Only long double handling uses these.
+// FPSCR is not modelled; we use the SDNode Flag to keep things in order.
+
+def MFFS : XForm_42<63, 583, (outs F8RC:$rT), (ins),
+ "mffs $rT", IntMFFS,
+ [(set F8RC:$rT, (PPCmffs))]>,
+ PPC970_DGroup_Single, PPC970_Unit_FPU;
+def MTFSB0 : XForm_43<63, 70, (outs), (ins u5imm:$FM),
+ "mtfsb0 $FM", IntMTFSB0,
+ [(PPCmtfsb0 (i32 imm:$FM))]>,
+ PPC970_DGroup_Single, PPC970_Unit_FPU;
+def MTFSB1 : XForm_43<63, 38, (outs), (ins u5imm:$FM),
+ "mtfsb1 $FM", IntMTFSB0,
+ [(PPCmtfsb1 (i32 imm:$FM))]>,
+ PPC970_DGroup_Single, PPC970_Unit_FPU;
+def FADDrtz: AForm_2<63, 21,
+ (outs F8RC:$FRT), (ins F8RC:$FRA, F8RC:$FRB),
+ "fadd $FRT, $FRA, $FRB", FPGeneral,
+ [(set F8RC:$FRT, (PPCfaddrtz F8RC:$FRA, F8RC:$FRB))]>,
+ PPC970_DGroup_Single, PPC970_Unit_FPU;
+// MTFSF does not actually produce an FP result. We pretend it copies
+// input reg B to the output. If we didn't do this it would look like the
+// instruction had no outputs (because we aren't modelling the FPSCR) and
+// it would be deleted.
+def MTFSF : XFLForm<63, 711, (outs F8RC:$FRA),
+ (ins i32imm:$FM, F8RC:$rT, F8RC:$FRB),
+ "mtfsf $FM, $rT", "$FRB = $FRA", IntMTFSB0,
+ [(set F8RC:$FRA, (PPCmtfsf (i32 imm:$FM),
+ F8RC:$rT, F8RC:$FRB))]>,
+ PPC970_DGroup_Single, PPC970_Unit_FPU;
+
let PPC970_Unit = 1 in { // FXU Operations.
// XO-Form instructions. Arithmetic instructions that can set overflow bit