llvm/lib/Target/AMDGPU/AMDGPUInstrInfo.cpp
2016-07-09 18:11:15 +00:00

121 lines
3.9 KiB
C++

//===-- AMDGPUInstrInfo.cpp - Base class for AMD GPU InstrInfo ------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
/// \file
/// \brief Implementation of the TargetInstrInfo class that is common to all
/// AMD GPUs.
//
//===----------------------------------------------------------------------===//
#include "AMDGPUInstrInfo.h"
#include "AMDGPURegisterInfo.h"
#include "AMDGPUTargetMachine.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
using namespace llvm;
#define GET_INSTRINFO_CTOR_DTOR
#define GET_INSTRINFO_NAMED_OPS
#define GET_INSTRMAP_INFO
#include "AMDGPUGenInstrInfo.inc"
// Pin the vtable to this file.
void AMDGPUInstrInfo::anchor() {}
AMDGPUInstrInfo::AMDGPUInstrInfo(const AMDGPUSubtarget &ST)
: AMDGPUGenInstrInfo(-1, -1), ST(ST) {}
bool AMDGPUInstrInfo::enableClusterLoads() const {
return true;
}
// FIXME: This behaves strangely. If, for example, you have 32 load + stores,
// the first 16 loads will be interleaved with the stores, and the next 16 will
// be clustered as expected. It should really split into 2 16 store batches.
//
// Loads are clustered until this returns false, rather than trying to schedule
// groups of stores. This also means we have to deal with saying different
// address space loads should be clustered, and ones which might cause bank
// conflicts.
//
// This might be deprecated so it might not be worth that much effort to fix.
bool AMDGPUInstrInfo::shouldScheduleLoadsNear(SDNode *Load0, SDNode *Load1,
int64_t Offset0, int64_t Offset1,
unsigned NumLoads) const {
assert(Offset1 > Offset0 &&
"Second offset should be larger than first offset!");
// If we have less than 16 loads in a row, and the offsets are within 64
// bytes, then schedule together.
// A cacheline is 64 bytes (for global memory).
return (NumLoads <= 16 && (Offset1 - Offset0) < 64);
}
int AMDGPUInstrInfo::getMaskedMIMGOp(uint16_t Opcode, unsigned Channels) const {
switch (Channels) {
default: return Opcode;
case 1: return AMDGPU::getMaskedMIMGOp(Opcode, AMDGPU::Channels_1);
case 2: return AMDGPU::getMaskedMIMGOp(Opcode, AMDGPU::Channels_2);
case 3: return AMDGPU::getMaskedMIMGOp(Opcode, AMDGPU::Channels_3);
}
}
// This must be kept in sync with the SIEncodingFamily class in SIInstrInfo.td
enum SIEncodingFamily {
SI = 0,
VI = 1
};
// Wrapper for Tablegen'd function. enum Subtarget is not defined in any
// header files, so we need to wrap it in a function that takes unsigned
// instead.
namespace llvm {
namespace AMDGPU {
static int getMCOpcode(uint16_t Opcode, unsigned Gen) {
return getMCOpcodeGen(Opcode, static_cast<Subtarget>(Gen));
}
}
}
static SIEncodingFamily subtargetEncodingFamily(const AMDGPUSubtarget &ST) {
switch (ST.getGeneration()) {
case AMDGPUSubtarget::SOUTHERN_ISLANDS:
case AMDGPUSubtarget::SEA_ISLANDS:
return SIEncodingFamily::SI;
case AMDGPUSubtarget::VOLCANIC_ISLANDS:
return SIEncodingFamily::VI;
// FIXME: This should never be called for r600 GPUs.
case AMDGPUSubtarget::R600:
case AMDGPUSubtarget::R700:
case AMDGPUSubtarget::EVERGREEN:
case AMDGPUSubtarget::NORTHERN_ISLANDS:
return SIEncodingFamily::SI;
}
llvm_unreachable("Unknown subtarget generation!");
}
int AMDGPUInstrInfo::pseudoToMCOpcode(int Opcode) const {
int MCOp = AMDGPU::getMCOpcode(Opcode, subtargetEncodingFamily(ST));
// -1 means that Opcode is already a native instruction.
if (MCOp == -1)
return Opcode;
// (uint16_t)-1 means that Opcode is a pseudo instruction that has
// no encoding in the given subtarget generation.
if (MCOp == (uint16_t)-1)
return -1;
return MCOp;
}