| //===-- llvm/Target/TargetOptions.h - Target Options ------------*- C++ -*-===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file defines command line option flags that are shared across various |
| // targets. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_TARGET_TARGETOPTIONS_H |
| #define LLVM_TARGET_TARGETOPTIONS_H |
| |
| #include "llvm/MC/MCTargetOptions.h" |
| |
| namespace llvm { |
| class MachineFunction; |
| class Module; |
| |
| namespace FloatABI { |
| enum ABIType { |
| Default, // Target-specific (either soft or hard depending on triple, etc). |
| Soft, // Soft float. |
| Hard // Hard float. |
| }; |
| } |
| |
| namespace FPOpFusion { |
| enum FPOpFusionMode { |
| Fast, // Enable fusion of FP ops wherever it's profitable. |
| Standard, // Only allow fusion of 'blessed' ops (currently just fmuladd). |
| Strict // Never fuse FP-ops. |
| }; |
| } |
| |
| namespace JumpTable { |
| enum JumpTableType { |
| Single, // Use a single table for all indirect jumptable calls. |
| Arity, // Use one table per number of function parameters. |
| Simplified, // Use one table per function type, with types projected |
| // into 4 types: pointer to non-function, struct, |
| // primitive, and function pointer. |
| Full // Use one table per unique function type |
| }; |
| } |
| |
| namespace ThreadModel { |
| enum Model { |
| POSIX, // POSIX Threads |
| Single // Single Threaded Environment |
| }; |
| } |
| |
| namespace FPDenormal { |
| enum DenormalMode { |
| IEEE, // IEEE 754 denormal numbers |
| PreserveSign, // the sign of a flushed-to-zero number is preserved in |
| // the sign of 0 |
| PositiveZero // denormals are flushed to positive zero |
| }; |
| } |
| |
| enum class EABI { |
| Unknown, |
| Default, // Default means not specified |
| EABI4, // Target-specific (either 4, 5 or gnu depending on triple). |
| EABI5, |
| GNU |
| }; |
| |
| /// Identify a debugger for "tuning" the debug info. |
| /// |
| /// The "debugger tuning" concept allows us to present a more intuitive |
| /// interface that unpacks into different sets of defaults for the various |
| /// individual feature-flag settings, that suit the preferences of the |
| /// various debuggers. However, it's worth remembering that debuggers are |
| /// not the only consumers of debug info, and some variations in DWARF might |
| /// better be treated as target/platform issues. Fundamentally, |
| /// o if the feature is useful (or not) to a particular debugger, regardless |
| /// of the target, that's a tuning decision; |
| /// o if the feature is useful (or not) on a particular platform, regardless |
| /// of the debugger, that's a target decision. |
| /// It's not impossible to see both factors in some specific case. |
| /// |
| /// The "tuning" should be used to set defaults for individual feature flags |
| /// in DwarfDebug; if a given feature has a more specific command-line option, |
| /// that option should take precedence over the tuning. |
| enum class DebuggerKind { |
| Default, // No specific tuning requested. |
| GDB, // Tune debug info for gdb. |
| LLDB, // Tune debug info for lldb. |
| SCE // Tune debug info for SCE targets (e.g. PS4). |
| }; |
| |
| /// Enable abort calls when global instruction selection fails to lower/select |
| /// an instruction. |
| enum class GlobalISelAbortMode { |
| Disable, // Disable the abort. |
| Enable, // Enable the abort. |
| DisableWithDiag // Disable the abort but emit a diagnostic on failure. |
| }; |
| |
| class TargetOptions { |
| public: |
| TargetOptions() |
| : PrintMachineCode(false), UnsafeFPMath(false), NoInfsFPMath(false), |
| NoNaNsFPMath(false), NoTrappingFPMath(true), |
| NoSignedZerosFPMath(false), |
| HonorSignDependentRoundingFPMathOption(false), NoZerosInBSS(false), |
| GuaranteedTailCallOpt(false), StackSymbolOrdering(true), |
| EnableFastISel(false), EnableGlobalISel(false), UseInitArray(false), |
| DisableIntegratedAS(false), RelaxELFRelocations(false), |
| FunctionSections(false), DataSections(false), |
| UniqueSectionNames(true), TrapUnreachable(false), |
| NoTrapAfterNoreturn(false), TLSSize(0), EmulatedTLS(false), |
| ExplicitEmulatedTLS(false), EnableIPRA(false), |
| EmitStackSizeSection(false), EnableMachineOutliner(false), |
| SupportsDefaultOutlining(false), EmitAddrsig(false), |
| EnableDebugEntryValues(false), ForceDwarfFrameSection(false) {} |
| |
| /// PrintMachineCode - This flag is enabled when the -print-machineinstrs |
| /// option is specified on the command line, and should enable debugging |
| /// output from the code generator. |
| unsigned PrintMachineCode : 1; |
| |
| /// DisableFramePointerElim - This returns true if frame pointer elimination |
| /// optimization should be disabled for the given machine function. |
| bool DisableFramePointerElim(const MachineFunction &MF) const; |
| |
| /// UnsafeFPMath - This flag is enabled when the |
| /// -enable-unsafe-fp-math flag is specified on the command line. When |
| /// this flag is off (the default), the code generator is not allowed to |
| /// produce results that are "less precise" than IEEE allows. This includes |
| /// use of X86 instructions like FSIN and FCOS instead of libcalls. |
| unsigned UnsafeFPMath : 1; |
| |
| /// NoInfsFPMath - This flag is enabled when the |
| /// -enable-no-infs-fp-math flag is specified on the command line. When |
| /// this flag is off (the default), the code generator is not allowed to |
| /// assume the FP arithmetic arguments and results are never +-Infs. |
| unsigned NoInfsFPMath : 1; |
| |
| /// NoNaNsFPMath - This flag is enabled when the |
| /// -enable-no-nans-fp-math flag is specified on the command line. When |
| /// this flag is off (the default), the code generator is not allowed to |
| /// assume the FP arithmetic arguments and results are never NaNs. |
| unsigned NoNaNsFPMath : 1; |
| |
| /// NoTrappingFPMath - This flag is enabled when the |
| /// -enable-no-trapping-fp-math is specified on the command line. This |
| /// specifies that there are no trap handlers to handle exceptions. |
| unsigned NoTrappingFPMath : 1; |
| |
| /// NoSignedZerosFPMath - This flag is enabled when the |
| /// -enable-no-signed-zeros-fp-math is specified on the command line. This |
| /// specifies that optimizations are allowed to treat the sign of a zero |
| /// argument or result as insignificant. |
| unsigned NoSignedZerosFPMath : 1; |
| |
| /// HonorSignDependentRoundingFPMath - This returns true when the |
| /// -enable-sign-dependent-rounding-fp-math is specified. If this returns |
| /// false (the default), the code generator is allowed to assume that the |
| /// rounding behavior is the default (round-to-zero for all floating point |
| /// to integer conversions, and round-to-nearest for all other arithmetic |
| /// truncations). If this is enabled (set to true), the code generator must |
| /// assume that the rounding mode may dynamically change. |
| unsigned HonorSignDependentRoundingFPMathOption : 1; |
| bool HonorSignDependentRoundingFPMath() const; |
| |
| /// NoZerosInBSS - By default some codegens place zero-initialized data to |
| /// .bss section. This flag disables such behaviour (necessary, e.g. for |
| /// crt*.o compiling). |
| unsigned NoZerosInBSS : 1; |
| |
| /// GuaranteedTailCallOpt - This flag is enabled when -tailcallopt is |
| /// specified on the commandline. When the flag is on, participating targets |
| /// will perform tail call optimization on all calls which use the fastcc |
| /// calling convention and which satisfy certain target-independent |
| /// criteria (being at the end of a function, having the same return type |
| /// as their parent function, etc.), using an alternate ABI if necessary. |
| unsigned GuaranteedTailCallOpt : 1; |
| |
| /// StackAlignmentOverride - Override default stack alignment for target. |
| unsigned StackAlignmentOverride = 0; |
| |
| /// StackSymbolOrdering - When true, this will allow CodeGen to order |
| /// the local stack symbols (for code size, code locality, or any other |
| /// heuristics). When false, the local symbols are left in whatever order |
| /// they were generated. Default is true. |
| unsigned StackSymbolOrdering : 1; |
| |
| /// EnableFastISel - This flag enables fast-path instruction selection |
| /// which trades away generated code quality in favor of reducing |
| /// compile time. |
| unsigned EnableFastISel : 1; |
| |
| /// EnableGlobalISel - This flag enables global instruction selection. |
| unsigned EnableGlobalISel : 1; |
| |
| /// EnableGlobalISelAbort - Control abort behaviour when global instruction |
| /// selection fails to lower/select an instruction. |
| GlobalISelAbortMode GlobalISelAbort = GlobalISelAbortMode::Enable; |
| |
| /// UseInitArray - Use .init_array instead of .ctors for static |
| /// constructors. |
| unsigned UseInitArray : 1; |
| |
| /// Disable the integrated assembler. |
| unsigned DisableIntegratedAS : 1; |
| |
| /// Compress DWARF debug sections. |
| DebugCompressionType CompressDebugSections = DebugCompressionType::None; |
| |
| unsigned RelaxELFRelocations : 1; |
| |
| /// Emit functions into separate sections. |
| unsigned FunctionSections : 1; |
| |
| /// Emit data into separate sections. |
| unsigned DataSections : 1; |
| |
| unsigned UniqueSectionNames : 1; |
| |
| /// Emit target-specific trap instruction for 'unreachable' IR instructions. |
| unsigned TrapUnreachable : 1; |
| |
| /// Do not emit a trap instruction for 'unreachable' IR instructions behind |
| /// noreturn calls, even if TrapUnreachable is true. |
| unsigned NoTrapAfterNoreturn : 1; |
| |
| /// Bit size of immediate TLS offsets (0 == use the default). |
| unsigned TLSSize : 8; |
| |
| /// EmulatedTLS - This flag enables emulated TLS model, using emutls |
| /// function in the runtime library.. |
| unsigned EmulatedTLS : 1; |
| |
| /// Whether -emulated-tls or -no-emulated-tls is set. |
| unsigned ExplicitEmulatedTLS : 1; |
| |
| /// This flag enables InterProcedural Register Allocation (IPRA). |
| unsigned EnableIPRA : 1; |
| |
| /// Emit section containing metadata on function stack sizes. |
| unsigned EmitStackSizeSection : 1; |
| |
| /// Enables the MachineOutliner pass. |
| unsigned EnableMachineOutliner : 1; |
| |
| /// Set if the target supports default outlining behaviour. |
| unsigned SupportsDefaultOutlining : 1; |
| |
| /// Emit address-significance table. |
| unsigned EmitAddrsig : 1; |
| |
| /// Emit debug info about parameter's entry values. |
| unsigned EnableDebugEntryValues : 1; |
| |
| /// Emit DWARF debug frame section. |
| unsigned ForceDwarfFrameSection : 1; |
| |
| /// FloatABIType - This setting is set by -float-abi=xxx option is specfied |
| /// on the command line. This setting may either be Default, Soft, or Hard. |
| /// Default selects the target's default behavior. Soft selects the ABI for |
| /// software floating point, but does not indicate that FP hardware may not |
| /// be used. Such a combination is unfortunately popular (e.g. |
| /// arm-apple-darwin). Hard presumes that the normal FP ABI is used. |
| FloatABI::ABIType FloatABIType = FloatABI::Default; |
| |
| /// AllowFPOpFusion - This flag is set by the -fuse-fp-ops=xxx option. |
| /// This controls the creation of fused FP ops that store intermediate |
| /// results in higher precision than IEEE allows (E.g. FMAs). |
| /// |
| /// Fast mode - allows formation of fused FP ops whenever they're |
| /// profitable. |
| /// Standard mode - allow fusion only for 'blessed' FP ops. At present the |
| /// only blessed op is the fmuladd intrinsic. In the future more blessed ops |
| /// may be added. |
| /// Strict mode - allow fusion only if/when it can be proven that the excess |
| /// precision won't effect the result. |
| /// |
| /// Note: This option only controls formation of fused ops by the |
| /// optimizers. Fused operations that are explicitly specified (e.g. FMA |
| /// via the llvm.fma.* intrinsic) will always be honored, regardless of |
| /// the value of this option. |
| FPOpFusion::FPOpFusionMode AllowFPOpFusion = FPOpFusion::Standard; |
| |
| /// ThreadModel - This flag specifies the type of threading model to assume |
| /// for things like atomics |
| ThreadModel::Model ThreadModel = ThreadModel::POSIX; |
| |
| /// EABIVersion - This flag specifies the EABI version |
| EABI EABIVersion = EABI::Default; |
| |
| /// Which debugger to tune for. |
| DebuggerKind DebuggerTuning = DebuggerKind::Default; |
| |
| /// FPDenormalMode - This flags specificies which denormal numbers the code |
| /// is permitted to require. |
| FPDenormal::DenormalMode FPDenormalMode = FPDenormal::IEEE; |
| |
| /// What exception model to use |
| ExceptionHandling ExceptionModel = ExceptionHandling::None; |
| |
| /// Machine level options. |
| MCTargetOptions MCOptions; |
| }; |
| |
| } // End llvm namespace |
| |
| #endif |