llvm-6502/lib/Target/Hexagon/HexagonScheduleV4.td
Andrew Trick 2661b411cc I'm introducing a new machine model to simultaneously allow simple
subtarget CPU descriptions and support new features of
MachineScheduler.

MachineModel has three categories of data:
1) Basic properties for coarse grained instruction cost model.
2) Scheduler Read/Write resources for simple per-opcode and operand cost model (TBD).
3) Instruction itineraties for detailed per-cycle reservation tables.

These will all live side-by-side. Any subtarget can use any
combination of them. Instruction itineraries will not change in the
near term. In the long run, I expect them to only be relevant for
in-order VLIW machines that have complex contraints and require a
precise scheduling/bundling model. Once itineraries are only actively
used by VLIW-ish targets, they could be replaced by something more
appropriate for those targets.

This tablegen backend rewrite sets things up for introducing
MachineModel type #2: per opcode/operand cost model.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159891 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-07 04:00:00 +00:00

66 lines
3.0 KiB
TableGen

//=-HexagonScheduleV4.td - HexagonV4 Scheduling Definitions --*- tablegen -*-=//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// There are four SLOTS (four parallel pipelines) in Hexagon V4 machine.
// This file describes that machine information.
//
// |===========|==================================================|
// | PIPELINE | Instruction Classes |
// |===========|==================================================|
// | SLOT0 | LD ST ALU32 MEMOP NV SYSTEM |
// |-----------|--------------------------------------------------|
// | SLOT1 | LD ST ALU32 |
// |-----------|--------------------------------------------------|
// | SLOT2 | XTYPE ALU32 J JR |
// |-----------|--------------------------------------------------|
// | SLOT3 | XTYPE ALU32 J CR |
// |===========|==================================================|
// Functional Units.
def SLOT0 : FuncUnit;
def SLOT1 : FuncUnit;
def SLOT2 : FuncUnit;
def SLOT3 : FuncUnit;
// Itinerary classes.
def NV_V4 : InstrItinClass;
def MEM_V4 : InstrItinClass;
// ALU64/M/S Instruction classes of V2 are collectively knownn as XTYPE in V4.
def PREFIX : InstrItinClass;
def HexagonItinerariesV4 :
ProcessorItineraries<[SLOT0, SLOT1, SLOT2, SLOT3], [], [
InstrItinData<ALU32 , [InstrStage<1, [SLOT0, SLOT1, SLOT2, SLOT3]>]>,
InstrItinData<ALU64 , [InstrStage<1, [SLOT2, SLOT3]>]>,
InstrItinData<CR , [InstrStage<1, [SLOT3]>]>,
InstrItinData<J , [InstrStage<1, [SLOT2, SLOT3]>]>,
InstrItinData<JR , [InstrStage<1, [SLOT2]>]>,
InstrItinData<LD , [InstrStage<1, [SLOT0, SLOT1]>]>,
InstrItinData<M , [InstrStage<1, [SLOT2, SLOT3]>]>,
InstrItinData<ST , [InstrStage<1, [SLOT0, SLOT1]>]>,
InstrItinData<S , [InstrStage<1, [SLOT2, SLOT3]>]>,
InstrItinData<SYS , [InstrStage<1, [SLOT0]>]>,
InstrItinData<NV_V4 , [InstrStage<1, [SLOT0]>]>,
InstrItinData<MEM_V4 , [InstrStage<1, [SLOT0]>]>,
InstrItinData<MARKER , [InstrStage<1, [SLOT0, SLOT1, SLOT2, SLOT3]>]>,
InstrItinData<PREFIX , [InstrStage<1, [SLOT0, SLOT1, SLOT2, SLOT3]>]>,
InstrItinData<PSEUDO , [InstrStage<1, [SLOT0, SLOT1, SLOT2, SLOT3]>]>
]>;
def HexagonModelV4 : SchedMachineModel {
// Max issue per cycle == bundle width.
let IssueWidth = 4;
let Itineraries = HexagonItinerariesV4;
}
//===----------------------------------------------------------------------===//
// Hexagon V4 Resource Definitions -
//===----------------------------------------------------------------------===//