Add intrinsics for Ivy Bridge's rdrand instruction.
The rdrand/cmov sequence is the same that is emitted by both
GCC and ICC.
Fixes PR13284.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160117 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 4dccd40..c242aaa 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -1176,6 +1176,7 @@
// We want to custom lower some of our intrinsics.
setOperationAction(ISD::INTRINSIC_WO_CHAIN, MVT::Other, Custom);
+ setOperationAction(ISD::INTRINSIC_W_CHAIN, MVT::Other, Custom);
// Only custom-lower 64-bit SADDO and friends on 64-bit because we don't
@@ -9810,6 +9811,38 @@
}
}
+SDValue
+X86TargetLowering::LowerINTRINSIC_W_CHAIN(SDValue Op, SelectionDAG &DAG) const {
+ DebugLoc dl = Op.getDebugLoc();
+ unsigned IntNo = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
+ switch (IntNo) {
+ default: return SDValue(); // Don't custom lower most intrinsics.
+
+ // RDRAND intrinsics.
+ case Intrinsic::x86_rdrand_16:
+ case Intrinsic::x86_rdrand_32:
+ case Intrinsic::x86_rdrand_64: {
+ // Emit the node with the right value type.
+ SDValue Result = DAG.getNode(X86ISD::RDRAND, dl,
+ DAG.getVTList(Op->getValueType(0), MVT::Glue));
+
+ // If the value returned by RDRAND was valid (CF=1), return 1. Otherwise
+ // return the value from Rand, which is always 0, casted to i32.
+ SDValue Ops[] = { DAG.getZExtOrTrunc(Result, dl, Op->getValueType(1)),
+ DAG.getConstant(1, Op->getValueType(1)),
+ DAG.getConstant(X86::COND_B, MVT::i32),
+ SDValue(Result.getNode(), 1) };
+ SDValue isValid = DAG.getNode(X86ISD::CMOV, dl,
+ DAG.getVTList(Op->getValueType(1), MVT::Glue),
+ Ops, 4);
+
+ // Return { result, isValid, chain }.
+ return DAG.getNode(ISD::MERGE_VALUES, dl, Op->getVTList(), Result, isValid,
+ Op.getOperand(0));
+ }
+ }
+}
+
SDValue X86TargetLowering::LowerRETURNADDR(SDValue Op,
SelectionDAG &DAG) const {
MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
@@ -10894,6 +10927,7 @@
case ISD::VAARG: return LowerVAARG(Op, DAG);
case ISD::VACOPY: return LowerVACOPY(Op, DAG);
case ISD::INTRINSIC_WO_CHAIN: return LowerINTRINSIC_WO_CHAIN(Op, DAG);
+ case ISD::INTRINSIC_W_CHAIN: return LowerINTRINSIC_W_CHAIN(Op, DAG);
case ISD::RETURNADDR: return LowerRETURNADDR(Op, DAG);
case ISD::FRAMEADDR: return LowerFRAMEADDR(Op, DAG);
case ISD::FRAME_TO_ARGS_OFFSET:
@@ -11228,6 +11262,7 @@
case X86ISD::SEG_ALLOCA: return "X86ISD::SEG_ALLOCA";
case X86ISD::WIN_FTOL: return "X86ISD::WIN_FTOL";
case X86ISD::SAHF: return "X86ISD::SAHF";
+ case X86ISD::RDRAND: return "X86ISD::RDRAND";
}
}
diff --git a/lib/Target/X86/X86ISelLowering.h b/lib/Target/X86/X86ISelLowering.h
index 2f561a0..41bdd06 100644
--- a/lib/Target/X86/X86ISelLowering.h
+++ b/lib/Target/X86/X86ISelLowering.h
@@ -322,6 +322,9 @@
// SAHF - Store contents of %ah into %eflags.
SAHF,
+ // RDRAND - Get a random integer and indicate whether it is valid in CF.
+ RDRAND,
+
// ATOMADD64_DAG, ATOMSUB64_DAG, ATOMOR64_DAG, ATOMAND64_DAG,
// ATOMXOR64_DAG, ATOMNAND64_DAG, ATOMSWAP64_DAG -
// Atomic 64-bit binary operations.
@@ -768,6 +771,7 @@
SDValue LowerVAARG(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerVACOPY(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerINTRINSIC_WO_CHAIN(SDValue Op, SelectionDAG &DAG) const;
+ SDValue LowerINTRINSIC_W_CHAIN(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerFRAME_TO_ARGS_OFFSET(SDValue Op, SelectionDAG &DAG) const;
diff --git a/lib/Target/X86/X86InstrInfo.td b/lib/Target/X86/X86InstrInfo.td
index 0f7b787..dc26d4c 100644
--- a/lib/Target/X86/X86InstrInfo.td
+++ b/lib/Target/X86/X86InstrInfo.td
@@ -65,6 +65,8 @@
def SDTX86sahf : SDTypeProfile<1, 1, [SDTCisVT<0, i32>, SDTCisVT<1, i8>]>;
+def SDTX86rdrand : SDTypeProfile<2, 0, [SDTCisInt<0>, SDTCisVT<1, i32>]>;
+
def SDTX86cas : SDTypeProfile<0, 3, [SDTCisPtrTy<0>, SDTCisInt<1>,
SDTCisVT<2, i8>]>;
def SDTX86caspair : SDTypeProfile<0, 1, [SDTCisPtrTy<0>]>;
@@ -137,6 +139,8 @@
def X86sahf : SDNode<"X86ISD::SAHF", SDTX86sahf>;
+def X86rdrand : SDNode<"X86ISD::RDRAND", SDTX86rdrand>;
+
def X86cas : SDNode<"X86ISD::LCMPXCHG_DAG", SDTX86cas,
[SDNPHasChain, SDNPInGlue, SDNPOutGlue, SDNPMayStore,
SDNPMayLoad, SDNPMemOperand]>;
@@ -1466,11 +1470,14 @@
//
let Predicates = [HasRDRAND], Defs = [EFLAGS] in {
def RDRAND16r : I<0xC7, MRM6r, (outs GR16:$dst), (ins),
- "rdrand{w}\t$dst", []>, OpSize, TB;
+ "rdrand{w}\t$dst",
+ [(set GR16:$dst, EFLAGS, (X86rdrand))]>, OpSize, TB;
def RDRAND32r : I<0xC7, MRM6r, (outs GR32:$dst), (ins),
- "rdrand{l}\t$dst", []>, TB;
+ "rdrand{l}\t$dst",
+ [(set GR32:$dst, EFLAGS, (X86rdrand))]>, TB;
def RDRAND64r : RI<0xC7, MRM6r, (outs GR64:$dst), (ins),
- "rdrand{q}\t$dst", []>, TB;
+ "rdrand{q}\t$dst",
+ [(set GR64:$dst, EFLAGS, (X86rdrand))]>, TB;
}
//===----------------------------------------------------------------------===//