diff options
3 files changed, 62 insertions, 0 deletions
diff --git a/backend/include/rcc/CodeGen/GlobalISel/InstructionSelector.h b/backend/include/rcc/CodeGen/GlobalISel/InstructionSelector.h index 4c69606..4bea4e7 100644 --- a/backend/include/rcc/CodeGen/GlobalISel/InstructionSelector.h +++ b/backend/include/rcc/CodeGen/GlobalISel/InstructionSelector.h @@ -3,6 +3,7 @@ #ifndef RCC_CODEGEN_GLOBALISEL_INSTRUCTIONSELECTOR_H #define RCC_CODEGEN_GLOBALISEL_INSTRUCTIONSELECTOR_H +#include "rcc/CodeGen/MachineIRTypes.h" #include "rcc/Support/Error.h" namespace rcc { @@ -28,6 +29,15 @@ public: constrainSelectedInstruction(MachineInstr &, MachineFunction &, const TargetDescription &) const { return {}; } + + [[nodiscard]] Expected<void> propagateSelectionFlags(MachineInstr &Output, + MachineInstrFlags InputFlags, + bool InputMayRaiseFPException, + const TargetDescription &Target) const; + + [[nodiscard]] Expected<void> propagateSelectionFlags(MachineInstr &Output, + const MachineInstr &Input, + const TargetDescription &Target) const; }; } // namespace rcc diff --git a/backend/lib/CodeGen/GlobalISel/InstructionSelect.cpp b/backend/lib/CodeGen/GlobalISel/InstructionSelect.cpp index 862b63f..1f7f453 100644 --- a/backend/lib/CodeGen/GlobalISel/InstructionSelect.cpp +++ b/backend/lib/CodeGen/GlobalISel/InstructionSelect.cpp @@ -169,6 +169,36 @@ void combineFingerprint(std::uint64_t &State, std::uint64_t Value) noexcept { } // namespace +Expected<void> InstructionSelector::propagateSelectionFlags(MachineInstr &Output, + MachineInstrFlags InputFlags, + bool InputMayRaiseFPException, + const TargetDescription &Target) const { + const InstructionDescriptor *OutputDescriptor = Target.instructionDescriptor(Output.opcode()); + if (OutputDescriptor == nullptr) { + return makeUnexpected(ErrorCode::VerificationError, + "instruction selector produced an unknown instruction descriptor"); + } + if (!InputMayRaiseFPException && + OutputDescriptor->Flags.has(InstructionFlag::MayRaiseFPException)) { + InputFlags.set(MachineInstrFlag::NoFPExcept); + } + Output.setFlags(InputFlags); + return {}; +} + +Expected<void> InstructionSelector::propagateSelectionFlags(MachineInstr &Output, + const MachineInstr &Input, + const TargetDescription &Target) const { + const InstructionDescriptor *InputDescriptor = Target.instructionDescriptor(Input.opcode()); + if (InputDescriptor == nullptr) { + return makeUnexpected(ErrorCode::VerificationError, + "instruction selector input has an unknown instruction descriptor"); + } + return propagateSelectionFlags(Output, Input.flags(), + InputDescriptor->Flags.has(InstructionFlag::MayRaiseFPException), + Target); +} + const MachinePassContract &InstructionSelect::contract() const noexcept { return instructionSelectContract(); } @@ -272,6 +302,9 @@ Expected<MachinePassResult> InstructionSelect::runImplementation(MachineFunction CurrentDescriptor->Name + "'", ErrorCode::VerificationError)); } + const MachineInstrFlags InputFlags = Instruction->flags(); + const bool InputMayRaiseFPException = + CurrentDescriptor->Flags.has(InstructionFlag::MayRaiseFPException); auto Selection = Info->select(*Instruction, Function, Target); if (!Selection) return std::unexpected(Selection.error()); @@ -279,6 +312,10 @@ Expected<MachinePassResult> InstructionSelect::runImplementation(MachineFunction if (Selected == nullptr) return std::unexpected( passFailure("instruction selector produced an unknown instruction descriptor")); + auto FlagPropagation = + Info->propagateSelectionFlags(*Instruction, InputFlags, InputMayRaiseFPException, Target); + if (!FlagPropagation) + return std::unexpected(FlagPropagation.error()); auto Constraint = Info->constrainSelectedInstruction(*Instruction, Function, Target); if (!Constraint) { return std::unexpected(withErrorContext( diff --git a/backend/lib/Target/RISCV/GISel/RISCVInstructionSelector.cpp b/backend/lib/Target/RISCV/GISel/RISCVInstructionSelector.cpp index 099de83..62c10af 100644 --- a/backend/lib/Target/RISCV/GISel/RISCVInstructionSelector.cpp +++ b/backend/lib/Target/RISCV/GISel/RISCVInstructionSelector.cpp @@ -660,6 +660,9 @@ private: auto Built = Pending->build(); if (!Built) return std::unexpected(Built.error()); + auto FlagPropagation = propagateSelectionFlags(**Built, Anchor, Builder.target()); + if (!FlagPropagation) + return std::unexpected(FlagPropagation.error()); auto Constraint = constrainSelectedInstruction(**Built, Builder.function(), Builder.target()); if (!Constraint) return std::unexpected(Constraint.error()); @@ -691,6 +694,9 @@ private: auto Built = Pending->build(); if (!Built) return std::unexpected(Built.error()); + auto FlagPropagation = propagateSelectionFlags(**Built, Anchor, Builder.target()); + if (!FlagPropagation) + return std::unexpected(FlagPropagation.error()); auto Constraint = constrainSelectedInstruction(**Built, Builder.function(), Builder.target()); if (!Constraint) return std::unexpected(Constraint.error()); @@ -719,6 +725,9 @@ private: auto Built = Pending->build(); if (!Built) return std::unexpected(Built.error()); + auto FlagPropagation = propagateSelectionFlags(**Built, Anchor, Builder.target()); + if (!FlagPropagation) + return std::unexpected(FlagPropagation.error()); auto Constraint = constrainSelectedInstruction(**Built, Builder.function(), Builder.target()); if (!Constraint) return std::unexpected(Constraint.error()); @@ -750,6 +759,9 @@ private: auto Built = Pending->build(); if (!Built) return std::unexpected(Built.error()); + auto FlagPropagation = propagateSelectionFlags(**Built, Anchor, Builder.target()); + if (!FlagPropagation) + return std::unexpected(FlagPropagation.error()); auto Constraint = constrainSelectedInstruction(**Built, Builder.function(), Builder.target()); if (!Constraint) return std::unexpected(Constraint.error()); @@ -823,6 +835,9 @@ private: auto Built = Pending->build(); if (!Built) return std::unexpected(Built.error()); + auto FlagPropagation = propagateSelectionFlags(**Built, Anchor, Builder.target()); + if (!FlagPropagation) + return std::unexpected(FlagPropagation.error()); auto Constraint = constrainSelectedInstruction(**Built, Builder.function(), Builder.target()); if (!Constraint) return std::unexpected(Constraint.error()); 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