1 //===-- llvm/Target/TargetInstrItineraries.h - Scheduling -------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the James M. Laskey and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file describes the structures used for instruction itineraries and
11 // states. This is used by schedulers to determine instruction states and
14 //===----------------------------------------------------------------------===//
16 #ifndef LLVM_TARGET_TARGETINSTRITINERARIES_H
17 #define LLVM_TARGET_TARGETINSTRITINERARIES_H
23 //===----------------------------------------------------------------------===//
24 // Instruction stage - These values represent a step in the execution of an
25 // instruction. The latency represents the number of discrete time slots used
26 // need to complete the stage. Units represent the choice of functional units
27 // that can be used to complete the stage. Eg. IntUnit1, IntUnit2.
30 unsigned Cycles; // Length of stage in machine cycles
31 unsigned Units; // Choice of functional units
35 //===----------------------------------------------------------------------===//
36 // Instruction itinerary - An itinerary represents a sequential series of steps
37 // required to complete an instruction. Itineraries are represented as
38 // sequences of instruction stages.
40 struct InstrItinerary {
41 unsigned First; // Index of first stage in itinerary
42 unsigned Last; // Index of last + 1 stage in itinerary
47 //===----------------------------------------------------------------------===//
48 // Instruction itinerary Data - Itinerary data supplied by a subtarget to be
51 struct InstrItineraryData {
52 InstrStage *Stages; // Array of stages selected
53 InstrItinerary *Itineratries; // Array of itineraries selected
58 InstrItineraryData() : Stages(NULL), Itineratries(NULL) {}
59 InstrItineraryData(InstrStage *S, InstrItinerary *I) : Stages(S), Itineratries(I) {}
62 // isEmpty - Returns true if there are no itineraries.
64 inline bool isEmpty() const { return Itineratries == NULL; }
67 // begin - Return the first stage of the itinerary.
69 inline InstrStage *begin(unsigned ItinClassIndx) const {
70 unsigned StageIdx = Itineratries[ItinClassIndx].First;
71 return Stages + StageIdx;
75 // end - Return the last+1 stage of the itinerary.
77 inline InstrStage *end(unsigned ItinClassIndx) const {
78 unsigned StageIdx = Itineratries[ItinClassIndx].Last;
79 return Stages + StageIdx;
84 } // End llvm namespace