llvm/lib/Target/SystemZ/SystemZSubtarget.cpp
Zhan Jun Liau 2738e9ca9e [SystemZ] Recognize Load On Condition Immediate (LOCHI/LOGHI) opportunities
Summary: Add support for the z13 instructions LOCHI and LOCGHI which
conditionally load immediate values.  Add target instruction info hooks so
that if conversion will allow predication of LHI/LGHI.

Author: RolandF

Reviewers: uweigand

Subscribers: zhanjunl

Commiting on behalf of Roland.

Differential Revision: http://reviews.llvm.org/D22117

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@275086 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-11 18:45:03 +00:00

63 lines
2.3 KiB
C++

//===-- SystemZSubtarget.cpp - SystemZ subtarget information --------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "SystemZSubtarget.h"
#include "MCTargetDesc/SystemZMCTargetDesc.h"
#include "llvm/IR/GlobalValue.h"
using namespace llvm;
#define DEBUG_TYPE "systemz-subtarget"
#define GET_SUBTARGETINFO_TARGET_DESC
#define GET_SUBTARGETINFO_CTOR
#include "SystemZGenSubtargetInfo.inc"
// Pin the vtable to this file.
void SystemZSubtarget::anchor() {}
SystemZSubtarget &
SystemZSubtarget::initializeSubtargetDependencies(StringRef CPU, StringRef FS) {
std::string CPUName = CPU;
if (CPUName.empty())
CPUName = "generic";
// Parse features string.
ParseSubtargetFeatures(CPUName, FS);
return *this;
}
SystemZSubtarget::SystemZSubtarget(const Triple &TT, const std::string &CPU,
const std::string &FS,
const TargetMachine &TM)
: SystemZGenSubtargetInfo(TT, CPU, FS), HasDistinctOps(false),
HasLoadStoreOnCond(false), HasHighWord(false), HasFPExtension(false),
HasPopulationCount(false), HasFastSerialization(false),
HasInterlockedAccess1(false), HasMiscellaneousExtensions(false),
HasTransactionalExecution(false), HasProcessorAssist(false),
HasVector(false), HasLoadStoreOnCond2(false), TargetTriple(TT),
InstrInfo(initializeSubtargetDependencies(CPU, FS)), TLInfo(TM, *this),
TSInfo(), FrameLowering() {}
bool SystemZSubtarget::isPC32DBLSymbol(const GlobalValue *GV,
CodeModel::Model CM) const {
// PC32DBL accesses require the low bit to be clear. Note that a zero
// value selects the default alignment and is therefore OK.
if (GV->getAlignment() == 1)
return false;
// For the small model, all locally-binding symbols are in range.
if (CM == CodeModel::Small)
return TLInfo.getTargetMachine().shouldAssumeDSOLocal(*GV->getParent(), GV);
// For Medium and above, assume that the symbol is not within the 4GB range.
// Taking the address of locally-defined text would be OK, but that
// case isn't easy to detect.
return false;
}