llvm-6502/lib/Target/PowerPC/PPCSubtarget.cpp
Jakob Stoklund Olesen 138c2b4e8a Revert r158337 "Move PPC host-CPU detection logic from PPCSubtarget into sys::getHostCPUName()."
This commit broke most of the PowerPC unit tests when running on
Intel/Apple.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158345 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-12 00:58:40 +00:00

266 lines
8.5 KiB
C++

//===-- PowerPCSubtarget.cpp - PPC Subtarget Information ------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the PPC specific subclass of TargetSubtargetInfo.
//
//===----------------------------------------------------------------------===//
#include "PPCSubtarget.h"
#include "PPCRegisterInfo.h"
#include "PPC.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/GlobalValue.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Support/DataStream.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/TargetRegistry.h"
#include <cstdlib>
#define GET_SUBTARGETINFO_TARGET_DESC
#define GET_SUBTARGETINFO_CTOR
#include "PPCGenSubtargetInfo.inc"
using namespace llvm;
#if defined(__APPLE__)
#include <mach/mach.h>
#include <mach/mach_host.h>
#include <mach/host_info.h>
#include <mach/machine.h>
/// GetCurrentPowerPCFeatures - Returns the current CPUs features.
static const char *GetCurrentPowerPCCPU() {
host_basic_info_data_t hostInfo;
mach_msg_type_number_t infoCount;
infoCount = HOST_BASIC_INFO_COUNT;
host_info(mach_host_self(), HOST_BASIC_INFO, (host_info_t)&hostInfo,
&infoCount);
if (hostInfo.cpu_type != CPU_TYPE_POWERPC) return "generic";
switch(hostInfo.cpu_subtype) {
case CPU_SUBTYPE_POWERPC_601: return "601";
case CPU_SUBTYPE_POWERPC_602: return "602";
case CPU_SUBTYPE_POWERPC_603: return "603";
case CPU_SUBTYPE_POWERPC_603e: return "603e";
case CPU_SUBTYPE_POWERPC_603ev: return "603ev";
case CPU_SUBTYPE_POWERPC_604: return "604";
case CPU_SUBTYPE_POWERPC_604e: return "604e";
case CPU_SUBTYPE_POWERPC_620: return "620";
case CPU_SUBTYPE_POWERPC_750: return "750";
case CPU_SUBTYPE_POWERPC_7400: return "7400";
case CPU_SUBTYPE_POWERPC_7450: return "7450";
case CPU_SUBTYPE_POWERPC_970: return "970";
default: ;
}
return "generic";
}
#elif defined(__linux__) && (defined(__ppc__) || defined(__powerpc__))
static const char *GetCurrentPowerPCCPU() {
// Access to the Processor Version Register (PVR) on PowerPC is privileged,
// and so we must use an operating-system interface to determine the current
// processor type. On Linux, this is exposed through the /proc/cpuinfo file.
const char *generic = "generic";
// Note: We cannot mmap /proc/cpuinfo here and then process the resulting
// memory buffer because the 'file' has 0 size (it can be read from only
// as a stream).
std::string Err;
DataStreamer *DS = getDataFileStreamer("/proc/cpuinfo", &Err);
if (!DS) {
DEBUG(dbgs() << "Unable to open /proc/cpuinfo: " << Err << "\n");
return generic;
}
// The cpu line is second (after the 'processor: 0' line), so if this
// buffer is too small then something has changed (or is wrong).
char buffer[1024];
size_t CPUInfoSize = DS->GetBytes((unsigned char*) buffer, sizeof(buffer));
delete DS;
const char *CPUInfoStart = buffer;
const char *CPUInfoEnd = buffer + CPUInfoSize;
const char *CIP = CPUInfoStart;
const char *CPUStart = 0;
size_t CPULen = 0;
// We need to find the first line which starts with cpu, spaces, and a colon.
// After the colon, there may be some additional spaces and then the cpu type.
while (CIP < CPUInfoEnd && CPUStart == 0) {
if (CIP < CPUInfoEnd && *CIP == '\n')
++CIP;
if (CIP < CPUInfoEnd && *CIP == 'c') {
++CIP;
if (CIP < CPUInfoEnd && *CIP == 'p') {
++CIP;
if (CIP < CPUInfoEnd && *CIP == 'u') {
++CIP;
while (CIP < CPUInfoEnd && (*CIP == ' ' || *CIP == '\t'))
++CIP;
if (CIP < CPUInfoEnd && *CIP == ':') {
++CIP;
while (CIP < CPUInfoEnd && (*CIP == ' ' || *CIP == '\t'))
++CIP;
if (CIP < CPUInfoEnd) {
CPUStart = CIP;
while (CIP < CPUInfoEnd && (*CIP != ' ' && *CIP != '\t' &&
*CIP != ',' && *CIP != '\n'))
++CIP;
CPULen = CIP - CPUStart;
}
}
}
}
}
if (CPUStart == 0)
while (CIP < CPUInfoEnd && *CIP != '\n')
++CIP;
}
if (CPUStart == 0)
return generic;
return StringSwitch<const char *>(StringRef(CPUStart, CPULen))
.Case("604e", "604e")
.Case("604", "604")
.Case("7400", "7400")
.Case("7410", "7400")
.Case("7447", "7400")
.Case("7455", "7450")
.Case("G4", "g4")
.Case("POWER4", "g4")
.Case("PPC970FX", "970")
.Case("PPC970MP", "970")
.Case("G5", "g5")
.Case("POWER5", "g5")
.Case("A2", "a2")
.Case("POWER6", "pwr6")
.Case("POWER7", "pwr7")
.Default(generic);
}
#endif
PPCSubtarget::PPCSubtarget(const std::string &TT, const std::string &CPU,
const std::string &FS, bool is64Bit)
: PPCGenSubtargetInfo(TT, CPU, FS)
, StackAlignment(16)
, DarwinDirective(PPC::DIR_NONE)
, HasMFOCRF(false)
, Has64BitSupport(false)
, Use64BitRegs(false)
, IsPPC64(is64Bit)
, HasAltivec(false)
, HasFSQRT(false)
, HasSTFIWX(false)
, IsBookE(false)
, HasLazyResolverStubs(false)
, IsJITCodeModel(false)
, TargetTriple(TT) {
// Determine default and user specified characteristics
std::string CPUName = CPU;
if (CPUName.empty())
CPUName = "generic";
#if defined(__APPLE__) || \
(defined(__linux__) && (defined(__ppc__) || defined(__powerpc__)))
if (CPUName == "generic")
CPUName = GetCurrentPowerPCCPU();
#endif
// Parse features string.
ParseSubtargetFeatures(CPUName, FS);
// Initialize scheduling itinerary for the specified CPU.
InstrItins = getInstrItineraryForCPU(CPUName);
// If we are generating code for ppc64, verify that options make sense.
if (is64Bit) {
Has64BitSupport = true;
// Silently force 64-bit register use on ppc64.
Use64BitRegs = true;
}
// If the user requested use of 64-bit regs, but the cpu selected doesn't
// support it, ignore.
if (use64BitRegs() && !has64BitSupport())
Use64BitRegs = false;
// Set up darwin-specific properties.
if (isDarwin())
HasLazyResolverStubs = true;
}
/// SetJITMode - This is called to inform the subtarget info that we are
/// producing code for the JIT.
void PPCSubtarget::SetJITMode() {
// JIT mode doesn't want lazy resolver stubs, it knows exactly where
// everything is. This matters for PPC64, which codegens in PIC mode without
// stubs.
HasLazyResolverStubs = false;
// Calls to external functions need to use indirect calls
IsJITCodeModel = true;
}
/// hasLazyResolverStub - Return true if accesses to the specified global have
/// to go through a dyld lazy resolution stub. This means that an extra load
/// is required to get the address of the global.
bool PPCSubtarget::hasLazyResolverStub(const GlobalValue *GV,
const TargetMachine &TM) const {
// We never have stubs if HasLazyResolverStubs=false or if in static mode.
if (!HasLazyResolverStubs || TM.getRelocationModel() == Reloc::Static)
return false;
// If symbol visibility is hidden, the extra load is not needed if
// the symbol is definitely defined in the current translation unit.
bool isDecl = GV->isDeclaration() && !GV->isMaterializable();
if (GV->hasHiddenVisibility() && !isDecl && !GV->hasCommonLinkage())
return false;
return GV->hasWeakLinkage() || GV->hasLinkOnceLinkage() ||
GV->hasCommonLinkage() || isDecl;
}
bool PPCSubtarget::enablePostRAScheduler(
CodeGenOpt::Level OptLevel,
TargetSubtargetInfo::AntiDepBreakMode& Mode,
RegClassVector& CriticalPathRCs) const {
// FIXME: It would be best to use TargetSubtargetInfo::ANTIDEP_ALL here,
// but we can't because we can't reassign the cr registers. There is a
// dependence between the cr register and the RLWINM instruction used
// to extract its value which the anti-dependency breaker can't currently
// see. Maybe we should make a late-expanded pseudo to encode this dependency.
// (the relevant code is in PPCDAGToDAGISel::SelectSETCC)
Mode = TargetSubtargetInfo::ANTIDEP_CRITICAL;
CriticalPathRCs.clear();
if (isPPC64())
CriticalPathRCs.push_back(&PPC::G8RCRegClass);
else
CriticalPathRCs.push_back(&PPC::GPRCRegClass);
CriticalPathRCs.push_back(&PPC::F8RCRegClass);
CriticalPathRCs.push_back(&PPC::VRRCRegClass);
return OptLevel >= CodeGenOpt::Default;
}