//===-- TargetMachine.cpp - General Target Information ---------------------==// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file describes the general parts of a Target machine. // //===----------------------------------------------------------------------===// #include "llvm/CodeGen/MachineFunction.h" #include "llvm/CodeGen/MachineFrameInfo.h" #include "llvm/MC/MCAsmInfo.h" #include "llvm/Target/TargetMachine.h" #include "llvm/Target/TargetOptions.h" #include "llvm/Support/CommandLine.h" using namespace llvm; //--------------------------------------------------------------------------- // Command-line options that tend to be useful on more than one back-end. // namespace llvm { bool LessPreciseFPMADOption; bool PrintMachineCode; bool NoFramePointerElim; bool NoFramePointerElimNonLeaf; bool NoExcessFPPrecision; bool UnsafeFPMath; bool NoInfsFPMath; bool NoNaNsFPMath; bool HonorSignDependentRoundingFPMathOption; bool UseSoftFloat; FloatABI::ABIType FloatABIType; bool NoImplicitFloat; bool NoZerosInBSS; bool JITExceptionHandling; bool JITEmitDebugInfo; bool JITEmitDebugInfoToDisk; bool UnwindTablesMandatory; Reloc::Model RelocationModel; CodeModel::Model CMModel; bool GuaranteedTailCallOpt; unsigned StackAlignment; bool RealignStack; bool DisableJumpTables; bool StrongPHIElim; bool HasDivModLibcall; bool AsmVerbosityDefault(false); } static cl::opt<bool, true> PrintCode("print-machineinstrs", cl::desc("Print generated machine code"), cl::location(PrintMachineCode), cl::init(false)); static cl::opt<bool, true> DisableFPElim("disable-fp-elim", cl::desc("Disable frame pointer elimination optimization"), cl::location(NoFramePointerElim), cl::init(false)); static cl::opt<bool, true> DisableFPElimNonLeaf("disable-non-leaf-fp-elim", cl::desc("Disable frame pointer elimination optimization for non-leaf funcs"), cl::location(NoFramePointerElimNonLeaf), cl::init(false)); static cl::opt<bool, true> DisableExcessPrecision("disable-excess-fp-precision", cl::desc("Disable optimizations that may increase FP precision"), cl::location(NoExcessFPPrecision), cl::init(false)); static cl::opt<bool, true> EnableFPMAD("enable-fp-mad", cl::desc("Enable less precise MAD instructions to be generated"), cl::location(LessPreciseFPMADOption), cl::init(false)); static cl::opt<bool, true> EnableUnsafeFPMath("enable-unsafe-fp-math", cl::desc("Enable optimizations that may decrease FP precision"), cl::location(UnsafeFPMath), cl::init(false)); static cl::opt<bool, true> EnableNoInfsFPMath("enable-no-infs-fp-math", cl::desc("Enable FP math optimizations that assume no +-Infs"), cl::location(NoInfsFPMath), cl::init(false)); static cl::opt<bool, true> EnableNoNaNsFPMath("enable-no-nans-fp-math", cl::desc("Enable FP math optimizations that assume no NaNs"), cl::location(NoNaNsFPMath), cl::init(false)); static cl::opt<bool, true> EnableHonorSignDependentRoundingFPMath("enable-sign-dependent-rounding-fp-math", cl::Hidden, cl::desc("Force codegen to assume rounding mode can change dynamically"), cl::location(HonorSignDependentRoundingFPMathOption), cl::init(false)); static cl::opt<bool, true> GenerateSoftFloatCalls("soft-float", cl::desc("Generate software floating point library calls"), cl::location(UseSoftFloat), cl::init(false)); static cl::opt<llvm::FloatABI::ABIType, true> FloatABIForCalls("float-abi", cl::desc("Choose float ABI type"), cl::location(FloatABIType), cl::init(FloatABI::Default), cl::values( clEnumValN(FloatABI::Default, "default", "Target default float ABI type"), clEnumValN(FloatABI::Soft, "soft", "Soft float ABI (implied by -soft-float)"), clEnumValN(FloatABI::Hard, "hard", "Hard float ABI (uses FP registers)"), clEnumValEnd)); static cl::opt<bool, true> DontPlaceZerosInBSS("nozero-initialized-in-bss", cl::desc("Don't place zero-initialized symbols into bss section"), cl::location(NoZerosInBSS), cl::init(false)); static cl::opt<bool, true> EnableJITExceptionHandling("jit-enable-eh", cl::desc("Emit exception handling information"), cl::location(JITExceptionHandling), cl::init(false)); // In debug builds, make this default to true. #ifdef NDEBUG #define EMIT_DEBUG false #else #define EMIT_DEBUG true #endif static cl::opt<bool, true> EmitJitDebugInfo("jit-emit-debug", cl::desc("Emit debug information to debugger"), cl::location(JITEmitDebugInfo), cl::init(EMIT_DEBUG)); #undef EMIT_DEBUG static cl::opt<bool, true> EmitJitDebugInfoToDisk("jit-emit-debug-to-disk", cl::Hidden, cl::desc("Emit debug info objfiles to disk"), cl::location(JITEmitDebugInfoToDisk), cl::init(false)); static cl::opt<bool, true> EnableUnwindTables("unwind-tables", cl::desc("Generate unwinding tables for all functions"), cl::location(UnwindTablesMandatory), cl::init(false)); static cl::opt<llvm::Reloc::Model, true> DefRelocationModel("relocation-model", cl::desc("Choose relocation model"), cl::location(RelocationModel), cl::init(Reloc::Default), cl::values( clEnumValN(Reloc::Default, "default", "Target default relocation model"), clEnumValN(Reloc::Static, "static", "Non-relocatable code"), clEnumValN(Reloc::PIC_, "pic", "Fully relocatable, position independent code"), clEnumValN(Reloc::DynamicNoPIC, "dynamic-no-pic", "Relocatable external references, non-relocatable code"), clEnumValEnd)); static cl::opt<llvm::CodeModel::Model, true> DefCodeModel("code-model", cl::desc("Choose code model"), cl::location(CMModel), cl::init(CodeModel::Default), cl::values( clEnumValN(CodeModel::Default, "default", "Target default code model"), clEnumValN(CodeModel::Small, "small", "Small code model"), clEnumValN(CodeModel::Kernel, "kernel", "Kernel code model"), clEnumValN(CodeModel::Medium, "medium", "Medium code model"), clEnumValN(CodeModel::Large, "large", "Large code model"), clEnumValEnd)); static cl::opt<bool, true> EnableGuaranteedTailCallOpt("tailcallopt", cl::desc("Turn fastcc calls into tail calls by (potentially) changing ABI."), cl::location(GuaranteedTailCallOpt), cl::init(false)); static cl::opt<unsigned, true> OverrideStackAlignment("stack-alignment", cl::desc("Override default stack alignment"), cl::location(StackAlignment), cl::init(0)); static cl::opt<bool, true> EnableRealignStack("realign-stack", cl::desc("Realign stack if needed"), cl::location(RealignStack), cl::init(true)); static cl::opt<bool, true> DisableSwitchTables(cl::Hidden, "disable-jump-tables", cl::desc("Do not generate jump tables."), cl::location(DisableJumpTables), cl::init(false)); static cl::opt<bool, true> EnableStrongPHIElim(cl::Hidden, "strong-phi-elim", cl::desc("Use strong PHI elimination."), cl::location(StrongPHIElim), cl::init(false)); static cl::opt<std::string> TrapFuncName("trap-func", cl::Hidden, cl::desc("Emit a call to trap function rather than a trap instruction"), cl::init("")); static cl::opt<bool> DataSections("fdata-sections", cl::desc("Emit data into separate sections"), cl::init(false)); static cl::opt<bool> FunctionSections("ffunction-sections", cl::desc("Emit functions into separate sections"), cl::init(false)); //--------------------------------------------------------------------------- // TargetMachine Class // TargetMachine::TargetMachine(const Target &T) : TheTarget(T), AsmInfo(0), MCRelaxAll(false), MCNoExecStack(false), MCSaveTempLabels(false), MCUseLoc(true), MCUseCFI(true) { // Typically it will be subtargets that will adjust FloatABIType from Default // to Soft or Hard. if (UseSoftFloat) FloatABIType = FloatABI::Soft; } TargetMachine::~TargetMachine() { delete AsmInfo; } /// getRelocationModel - Returns the code generation relocation model. The /// choices are static, PIC, and dynamic-no-pic, and target default. Reloc::Model TargetMachine::getRelocationModel() { return RelocationModel; } /// setRelocationModel - Sets the code generation relocation model. void TargetMachine::setRelocationModel(Reloc::Model Model) { RelocationModel = Model; } /// getCodeModel - Returns the code model. The choices are small, kernel, /// medium, large, and target default. CodeModel::Model TargetMachine::getCodeModel() { return CMModel; } /// setCodeModel - Sets the code model. void TargetMachine::setCodeModel(CodeModel::Model Model) { CMModel = Model; } bool TargetMachine::getAsmVerbosityDefault() { return AsmVerbosityDefault; } void TargetMachine::setAsmVerbosityDefault(bool V) { AsmVerbosityDefault = V; } bool TargetMachine::getFunctionSections() { return FunctionSections; } bool TargetMachine::getDataSections() { return DataSections; } void TargetMachine::setFunctionSections(bool V) { FunctionSections = V; } void TargetMachine::setDataSections(bool V) { DataSections = V; } namespace llvm { /// DisableFramePointerElim - This returns true if frame pointer elimination /// optimization should be disabled for the given machine function. bool DisableFramePointerElim(const MachineFunction &MF) { // Check to see if we should eliminate non-leaf frame pointers and then // check to see if we should eliminate all frame pointers. if (NoFramePointerElimNonLeaf && !NoFramePointerElim) { const MachineFrameInfo *MFI = MF.getFrameInfo(); return MFI->hasCalls(); } return NoFramePointerElim; } /// LessPreciseFPMAD - This flag return true when -enable-fp-mad option /// is specified on the command line. When this flag is off(default), the /// code generator is not allowed to generate mad (multiply add) if the /// result is "less precise" than doing those operations individually. bool LessPreciseFPMAD() { return UnsafeFPMath || LessPreciseFPMADOption; } /// HonorSignDependentRoundingFPMath - Return true if the codegen must assume /// that the rounding mode of the FPU can change from its default. bool HonorSignDependentRoundingFPMath() { return !UnsafeFPMath && HonorSignDependentRoundingFPMathOption; } /// getTrapFunctionName - If this returns a non-empty string, this means isel /// should lower Intrinsic::trap to a call to the specified function name /// instead of an ISD::TRAP node. StringRef getTrapFunctionName() { return TrapFuncName; } }