From 7d763c8b0ae6eee5f015fa82c744bff4c7ec8c8b Mon Sep 17 00:00:00 2001 From: Richard-Qin-X Date: Sat, 15 Aug 2026 03:11:22 +0800 Subject: [GlobalISel] Preserve worklists when moving CSE instructions --- backend/lib/CodeGen/MachineBasicBlock.cpp | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) (limited to 'backend/lib/CodeGen/MachineBasicBlock.cpp') diff --git a/backend/lib/CodeGen/MachineBasicBlock.cpp b/backend/lib/CodeGen/MachineBasicBlock.cpp index 763a577..2de8f89 100644 --- a/backend/lib/CodeGen/MachineBasicBlock.cpp +++ b/backend/lib/CodeGen/MachineBasicBlock.cpp @@ -99,6 +99,34 @@ Expected MachineBasicBlock::insertInstructionAfter(MachineInstr &Position, return {}; } +Expected MachineBasicBlock::spliceInstructionBefore(MachineInstr &Position, + MachineInstr &Instruction) { + if (Position.parent() != this || Instruction.parent() != this) { + return makeUnexpected(ErrorCode::InvalidArgument, + "instruction splice requires two instructions in this block"); + } + if (&Position == &Instruction || Instruction.NextInstruction == &Position) + return {}; + + if (Instruction.PreviousInstruction != nullptr) + Instruction.PreviousInstruction->NextInstruction = Instruction.NextInstruction; + else + FirstInstruction = Instruction.NextInstruction; + if (Instruction.NextInstruction != nullptr) + Instruction.NextInstruction->PreviousInstruction = Instruction.PreviousInstruction; + else + LastInstruction = Instruction.PreviousInstruction; + + Instruction.PreviousInstruction = Position.PreviousInstruction; + Instruction.NextInstruction = &Position; + if (Position.PreviousInstruction != nullptr) + Position.PreviousInstruction->NextInstruction = &Instruction; + else + FirstInstruction = &Instruction; + Position.PreviousInstruction = &Instruction; + return {}; +} + Expected MachineBasicBlock::removeInstruction(MachineInstr &Instruction) { if (Instruction.parent() != this) { return makeUnexpected(ErrorCode::InvalidArgument, "instruction does not belong to this block"); -- cgit v1.2.3