diff --git a/llvm/docs/LangRef.rst b/llvm/docs/LangRef.rst --- a/llvm/docs/LangRef.rst +++ b/llvm/docs/LangRef.rst @@ -22104,6 +22104,8 @@ These functions read or write floating point environment, such as rounding mode or state of floating point exceptions. Altering the floating point environment requires special care. See :ref:`Floating Point Environment `. +Functions that access floating point environment are ordered with other functions +that depend on the environment, including constrained FP intrinsics. '``llvm.flt.rounds``' Intrinsic ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ @@ -22169,6 +22171,102 @@ modes. +'``llvm.get.fpmode``' Intrinsic +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +Syntax: +""""""" + +This is an overloaded intrinsic. The overloaded type is an integer type used by +a particular target to represent floating-point control modes. + +:: + + declare @llvm.get.fpmode.() + +Overview: +""""""""" + +The '``llvm.get.fpmode``' intrinsic reads the current dynamic floating-point +control modes. + +Arguments: +"""""""""" + +None. + +Semantics: +"""""""""" + +The '``llvm.get.fpmode``' intrinsic reads the current dynamic floating-point +control modes, such as rounding direction, precision, treatment of denormals and +so on. It is similar to the C library function 'fegetmode', however this +function does not store the set of control modes into memory but returns it as +an integer value. Interpretation of the bits in this value is target-dependent. + +'``llvm.set.fpmode``' Intrinsic +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +Syntax: +""""""" + +This is an overloaded intrinsic. The overloaded type is an integer type used by +a particular target to represent floating-point control modes. + +:: + + declare void @llvm.set.fpmode.( ) + +Overview: +""""""""" + +The '``llvm.set.fpmode``' intrinsic sets the current dynamic floating-point +control modes. + +Arguments: +"""""""""" + +The argument is a set of floating-point control modes, represented as an integer +value in a target-dependent way. + +Semantics: +"""""""""" + +The '``llvm.set.fpmode``' intrinsic sets the current dynamic floating-point +control modes to the state specified by the argument, which must be obtained by +a call to '``llvm.get.fpmode``' or constructed in a target-specific way. It is +similar to the C library function 'fesetmode', however this function does not +read the set of control modes from memory but gets it as integer value. + +'``llvm.reset.fpmode``' Intrinsic +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +Syntax: +""""""" + +:: + + declare void @llvm.reset.fpmode() + +Overview: +""""""""" + +The '``llvm.reset.fpmode``' intrinsic sets the default dynamic floating-point +control modes. + +Arguments: +"""""""""" + +None. + +Semantics: +"""""""""" + +The '``llvm.reset.fpmode``' intrinsic sets the current dynamic floating-point +environment to the default state. It is similar to the C library function call +'fesetmode(FE_DFL_MODE)', however this function does not return any value. + + General Intrinsics ------------------ diff --git a/llvm/include/llvm/CodeGen/ISDOpcodes.h b/llvm/include/llvm/CodeGen/ISDOpcodes.h --- a/llvm/include/llvm/CodeGen/ISDOpcodes.h +++ b/llvm/include/llvm/CodeGen/ISDOpcodes.h @@ -914,6 +914,19 @@ /// FSINCOS - Compute both fsin and fcos as a single operation. FSINCOS, + /// Reads the current dynamic floating-point control modes. The operand is + /// the token chain. + GET_FPMODE, + + /// Sets the current dynamic floating-point control modes. The first operand + /// is the token chain, the second is control modes set represented as integer + /// value. + SET_FPMODE, + + /// Sets default dynamic floating-point control modes. The operand is the + /// token chain. + RESET_FPMODE, + /// LOAD and STORE have token chains as their first operand, then the same /// operands as an LLVM load/store instruction, then an offset node that /// is added / subtracted from the base pointer to form the address (for diff --git a/llvm/include/llvm/IR/IRBuilder.h b/llvm/include/llvm/IR/IRBuilder.h --- a/llvm/include/llvm/IR/IRBuilder.h +++ b/llvm/include/llvm/IR/IRBuilder.h @@ -2369,6 +2369,22 @@ return CreateFCmpHelper(P, LHS, RHS, Name, FPMathTag, true); } + /// Create call to the get_fpmode intrinsic. + CallInst *createGetFPMode(unsigned ModeSize, const Twine &Name = "") { + assert(BB && BB->getParent() && "No current basic block!"); + assert(ModeSize > 0 && "FP mode size is unknown"); + Module *M = BB->getModule(); + auto ModeTy = IntegerType::get(M->getContext(), ModeSize); + return CreateIntrinsic(Intrinsic::get_fpmode, {ModeTy}, {}, nullptr, Name); + } + + /// Create call to the set_fpmode intrinsic. + /// \param Mode Set of floating-point modes. + CallInst *createSetFPMode(Value *Mode, const Twine &Name = "") { + return CreateIntrinsic(Intrinsic::set_fpmode, {Mode->getType()}, {Mode}, + nullptr, Name); + } + private: // Helper routine to create either a signaling or a quiet FP comparison. Value *CreateFCmpHelper(CmpInst::Predicate P, Value *LHS, Value *RHS, diff --git a/llvm/include/llvm/IR/Intrinsics.td b/llvm/include/llvm/IR/Intrinsics.td --- a/llvm/include/llvm/IR/Intrinsics.td +++ b/llvm/include/llvm/IR/Intrinsics.td @@ -715,6 +715,9 @@ let IntrProperties = [IntrInaccessibleMemOnly, IntrWillReturn] in { def int_flt_rounds : DefaultAttrsIntrinsic<[llvm_i32_ty], []>; def int_set_rounding : DefaultAttrsIntrinsic<[], [llvm_i32_ty]>; + def int_get_fpmode : DefaultAttrsIntrinsic<[llvm_anyint_ty], []>; + def int_set_fpmode : DefaultAttrsIntrinsic<[], [llvm_anyint_ty]>; + def int_reset_fpmode : DefaultAttrsIntrinsic<[], []>; } //===--------------- Constrained Floating Point Intrinsics ----------------===// diff --git a/llvm/include/llvm/IR/RuntimeLibcalls.def b/llvm/include/llvm/IR/RuntimeLibcalls.def --- a/llvm/include/llvm/IR/RuntimeLibcalls.def +++ b/llvm/include/llvm/IR/RuntimeLibcalls.def @@ -280,6 +280,10 @@ HANDLE_LIBCALL(LLRINT_F128, "llrintl") HANDLE_LIBCALL(LLRINT_PPCF128, "llrintl") +// Floating point environment +HANDLE_LIBCALL(FEGETMODE, "fegetmode") +HANDLE_LIBCALL(FESETMODE, "fesetmode") + // Conversion HANDLE_LIBCALL(FPEXT_F32_PPCF128, "__gcc_stoq") HANDLE_LIBCALL(FPEXT_F64_PPCF128, "__gcc_dtoq") diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp --- a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp @@ -185,6 +185,9 @@ SDValue ExpandInsertToVectorThroughStack(SDValue Op); SDValue ExpandVectorBuildThroughStack(SDNode* Node); + SDValue makeStateFunctionCall(const SDLoc &DL, RTLIB::Libcall LC, + SDValue Chain, SDValue MemOp); + SDValue ExpandConstantFP(ConstantFPSDNode *CFP, bool UseCP); SDValue ExpandConstant(ConstantSDNode *CP); @@ -1207,6 +1210,7 @@ case ISD::VP_REDUCE_FMIN: case ISD::VP_REDUCE_SEQ_FADD: case ISD::VP_REDUCE_SEQ_FMUL: + case ISD::SET_FPMODE: Action = TLI.getOperationAction( Node->getOpcode(), Node->getOperand(1).getValueType()); break; @@ -1509,6 +1513,39 @@ return DAG.getLoad(VT, dl, StoreChain, FIPtr, PtrInfo); } +/// Helper used to make a call to a library function that has one argument of +/// pointer type. +/// Examples of such functions are 'fegetmode', 'fesetenv' and some others, +/// which are used to get or set some state. Return value of the library +/// function is ignored. +/// +/// \param DL Debug location of the new call. +/// \param LC Identifies library function. +/// \param Chain Ingoing token chain. +/// \param MemOp Memory operand provided as an argument for the function call. +/// \returns Outgoing token chain. +/// +SDValue SelectionDAGLegalize::makeStateFunctionCall(const SDLoc &DL, + RTLIB::Libcall LC, + SDValue Chain, + SDValue MemOp) { + TargetLowering::ArgListTy Args; + TargetLowering::ArgListEntry Entry; + Entry.Node = MemOp; + Entry.Ty = MemOp.getValueType().getTypeForEVT(*DAG.getContext()); + Args.push_back(Entry); + SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC), + TLI.getPointerTy(DAG.getDataLayout())); + TargetLowering::CallLoweringInfo CLI(DAG); + CLI.setDebugLoc(DL) + .setChain(Chain) + .setIsPostTypeLegalization(true) + .setLibCallee(TLI.getLibcallCallingConv(LC), + Type::getVoidTy(*DAG.getContext()), Callee, + std::move(Args)); + return TLI.LowerCallTo(CLI).second; +} + /// Bitcast a floating-point value to an integer value. Only bitcast the part /// containing the sign bit if the target has no integer value capable of /// holding all bits of the floating-point value. @@ -4356,6 +4393,47 @@ break; } break; + case ISD::GET_FPMODE: { + // Call fegetmode, which saves control modes into a stack slot. Then load + // the value to return from the stack. + SDValue StackPtr = DAG.CreateStackTemporary(Node->getValueType(0)); + int SPFI = cast(StackPtr.getNode())->getIndex(); + SDValue Chain = makeStateFunctionCall(SDLoc(Node), RTLIB::FEGETMODE, + Node->getOperand(0), StackPtr); + SDValue LdInst = DAG.getLoad( + StackPtr.getValueType(), dl, Chain, StackPtr, + MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), SPFI)); + Results.push_back(LdInst); + Results.push_back(LdInst.getValue(1)); + break; + } + case ISD::SET_FPMODE: { + // Move control modes to stack slot and then call fesetmode with the pointer + // to the slot as argument. + SDValue Mode = Node->getOperand(1); + EVT ModeVT = Mode.getValueType(); + SDValue StackPtr = DAG.CreateStackTemporary(ModeVT); + int SPFI = cast(StackPtr.getNode())->getIndex(); + SDValue StInst = DAG.getStore( + Node->getOperand(0), dl, Mode, StackPtr, + MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), SPFI)); + Results.push_back( + makeStateFunctionCall(SDLoc(Node), RTLIB::FESETMODE, StInst, StackPtr)); + break; + } + case ISD::RESET_FPMODE: { + // It is legalized to a call 'fesetmode(FE_DFL_MODE)'. On most targets + // FE_DFL_MODE is defined as '((const femode_t *) -1)' in glibc. If not, the + // target must provide custom lowering. + const DataLayout &DL = DAG.getDataLayout(); + Type *ByteTy = EVT(MVT::i8).getTypeForEVT(*DAG.getContext()); + auto *PtrTy = PointerType::get(ByteTy, DL.getAllocaAddrSpace()); + Type *IntTy = DL.getIntPtrType(PtrTy); + SDValue Mode = DAG.getConstant(-1LL, dl, MVT::getVT(IntTy)); + Results.push_back(makeStateFunctionCall(SDLoc(Node), RTLIB::FESETMODE, + Node->getOperand(0), Mode)); + break; + } } // Replace the original node with the legalized result. diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp --- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp @@ -6385,6 +6385,25 @@ setValue(&I, Res); DAG.setRoot(Res.getValue(0)); return; + case Intrinsic::get_fpmode: + Res = DAG.getNode( + ISD::GET_FPMODE, sdl, + DAG.getVTList(TLI.getValueType(DAG.getDataLayout(), I.getType()), + MVT::Other), + DAG.getRoot()); + setValue(&I, Res); + DAG.setRoot(Res.getValue(1)); + return; + case Intrinsic::set_fpmode: + Res = DAG.getNode(ISD::SET_FPMODE, sdl, MVT::Other, {DAG.getRoot()}, + getValue(I.getArgOperand(0))); + DAG.setRoot(Res); + return; + case Intrinsic::reset_fpmode: { + Res = DAG.getNode(ISD::RESET_FPMODE, sdl, MVT::Other, getRoot()); + DAG.setRoot(Res); + return; + } case Intrinsic::pcmarker: { SDValue Tmp = getValue(I.getArgOperand(0)); DAG.setRoot(DAG.getNode(ISD::PCMARKER, sdl, MVT::Other, getRoot(), Tmp)); diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp --- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp @@ -418,6 +418,9 @@ // Floating point environment manipulation case ISD::FLT_ROUNDS_: return "flt_rounds"; case ISD::SET_ROUNDING: return "set_rounding"; + case ISD::GET_FPMODE: return "get_fpmode"; + case ISD::SET_FPMODE: return "set_fpmode"; + case ISD::RESET_FPMODE: return "reset_fpmode"; // Bit manipulation case ISD::ABS: return "abs"; diff --git a/llvm/lib/CodeGen/TargetLoweringBase.cpp b/llvm/lib/CodeGen/TargetLoweringBase.cpp --- a/llvm/lib/CodeGen/TargetLoweringBase.cpp +++ b/llvm/lib/CodeGen/TargetLoweringBase.cpp @@ -913,6 +913,13 @@ setOperationAction(ISD::DEBUGTRAP, MVT::Other, Expand); setOperationAction(ISD::UBSANTRAP, MVT::Other, Expand); + + // FP environment operations default to expand to library calls. + for (MVT VT : {MVT::i8, MVT::i16, MVT::i32, MVT::i64}) + setOperationAction(ISD::GET_FPMODE, VT, Expand); + for (MVT VT : {MVT::i8, MVT::i16, MVT::i32, MVT::i64}) + setOperationAction(ISD::SET_FPMODE, VT, Expand); + setOperationAction(ISD::RESET_FPMODE, MVT::Other, Expand); } MVT TargetLoweringBase::getScalarShiftAmountTy(const DataLayout &DL, diff --git a/llvm/test/CodeGen/Generic/fpenv.ll b/llvm/test/CodeGen/Generic/fpenv.ll new file mode 100644 --- /dev/null +++ b/llvm/test/CodeGen/Generic/fpenv.ll @@ -0,0 +1,31 @@ +; RUN: llc -mtriple=i686-unknown-linux-gnu -mattr=+soft-float -o - < %s | FileCheck %s +; REQUIRES: x86-registered-target + +define i32 @func_01() nounwind { +entry: + %fpmode = call i32 @llvm.get.fpmode.i32() + ret i32 %fpmode +} +; CHECK-LABEL: func_01: +; CHECK: calll fegetmode + +define void @func_02(i32 %fpmode) nounwind { +entry: + call void @llvm.set.fpmode.i32(i32 %fpmode) + ret void +} +; CHECK-LABEL: func_02: +; CHECK: calll fesetmode + + +define void @func_03() nounwind { +entry: + call void @llvm.reset.fpmode() + ret void +} +; CHECK-LABEL: func_03: +; CHECK: calll fesetmode + +declare i32 @llvm.get.fpmode.i32() +declare void @llvm.set.fpmode.i32(i32 %fpenv) +declare void @llvm.reset.fpmode() diff --git a/llvm/unittests/IR/IRBuilderTest.cpp b/llvm/unittests/IR/IRBuilderTest.cpp --- a/llvm/unittests/IR/IRBuilderTest.cpp +++ b/llvm/unittests/IR/IRBuilderTest.cpp @@ -1051,4 +1051,20 @@ Builder.CreateAdd(Builder.getInt32(1), Builder.getInt32(2), "add"); EXPECT_EQ(Add->getName(), "add"); } + +TEST_F(IRBuilderTest, FPEnvironment) { + IRBuilder<> Builder(BB); + CallInst *Call; + IntrinsicInst *II; + + Call = Builder.createGetFPMode(32); + II = cast(Call); + EXPECT_EQ(Intrinsic::get_fpmode, II->getIntrinsicID()); + EXPECT_TRUE(isa(Call->getType())); + EXPECT_EQ(32U, cast(Call->getType())->getBitWidth()); + + Call = Builder.createSetFPMode(Call); + II = cast(Call); + EXPECT_EQ(Intrinsic::set_fpmode, II->getIntrinsicID()); +} }