llvm-6502/lib/Target/PowerPC/MCTargetDesc/PPCELFObjectWriter.cpp
Justin Hibbits fcd08c294a Add support for small-model PIC for PowerPC.
Summary:
Large-model was added first.  With the addition of support for multiple PIC
models in LLVM, now add small-model PIC for 32-bit PowerPC, SysV4 ABI.  This
generates more optimal code, for shared libraries with less than about 16380
data objects.

Test Plan: Test cases added or updated

Reviewers: joerg, hfinkel

Reviewed By: hfinkel

Subscribers: jholewinski, mcrosier, emaste, llvm-commits

Differential Revision: http://reviews.llvm.org/D5399

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221791 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-12 15:16:30 +00:00

422 lines
14 KiB
C++

//===-- PPCELFObjectWriter.cpp - PPC ELF Writer ---------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "MCTargetDesc/PPCMCTargetDesc.h"
#include "MCTargetDesc/PPCFixupKinds.h"
#include "MCTargetDesc/PPCMCExpr.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/MC/MCELF.h"
#include "llvm/MC/MCELFObjectWriter.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCValue.h"
#include "llvm/Support/ErrorHandling.h"
using namespace llvm;
namespace {
class PPCELFObjectWriter : public MCELFObjectTargetWriter {
public:
PPCELFObjectWriter(bool Is64Bit, uint8_t OSABI);
protected:
unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
bool IsPCRel) const override;
bool needsRelocateWithSymbol(const MCSymbolData &SD,
unsigned Type) const override;
};
}
PPCELFObjectWriter::PPCELFObjectWriter(bool Is64Bit, uint8_t OSABI)
: MCELFObjectTargetWriter(Is64Bit, OSABI,
Is64Bit ? ELF::EM_PPC64 : ELF::EM_PPC,
/*HasRelocationAddend*/ true) {}
static MCSymbolRefExpr::VariantKind getAccessVariant(const MCValue &Target,
const MCFixup &Fixup) {
const MCExpr *Expr = Fixup.getValue();
if (Expr->getKind() != MCExpr::Target)
return Target.getAccessVariant();
switch (cast<PPCMCExpr>(Expr)->getKind()) {
case PPCMCExpr::VK_PPC_None:
return MCSymbolRefExpr::VK_None;
case PPCMCExpr::VK_PPC_LO:
return MCSymbolRefExpr::VK_PPC_LO;
case PPCMCExpr::VK_PPC_HI:
return MCSymbolRefExpr::VK_PPC_HI;
case PPCMCExpr::VK_PPC_HA:
return MCSymbolRefExpr::VK_PPC_HA;
case PPCMCExpr::VK_PPC_HIGHERA:
return MCSymbolRefExpr::VK_PPC_HIGHERA;
case PPCMCExpr::VK_PPC_HIGHER:
return MCSymbolRefExpr::VK_PPC_HIGHER;
case PPCMCExpr::VK_PPC_HIGHEST:
return MCSymbolRefExpr::VK_PPC_HIGHEST;
case PPCMCExpr::VK_PPC_HIGHESTA:
return MCSymbolRefExpr::VK_PPC_HIGHESTA;
}
llvm_unreachable("unknown PPCMCExpr kind");
}
unsigned PPCELFObjectWriter::GetRelocType(const MCValue &Target,
const MCFixup &Fixup,
bool IsPCRel) const {
MCSymbolRefExpr::VariantKind Modifier = getAccessVariant(Target, Fixup);
// determine the type of the relocation
unsigned Type;
if (IsPCRel) {
switch ((unsigned)Fixup.getKind()) {
default:
llvm_unreachable("Unimplemented");
case PPC::fixup_ppc_br24:
case PPC::fixup_ppc_br24abs:
switch (Modifier) {
default: llvm_unreachable("Unsupported Modifier");
case MCSymbolRefExpr::VK_None:
Type = ELF::R_PPC_REL24;
break;
case MCSymbolRefExpr::VK_PLT:
Type = ELF::R_PPC_PLTREL24;
break;
case MCSymbolRefExpr::VK_PPC_LOCAL:
Type = ELF::R_PPC_LOCAL24PC;
break;
}
break;
case PPC::fixup_ppc_brcond14:
case PPC::fixup_ppc_brcond14abs:
Type = ELF::R_PPC_REL14;
break;
case PPC::fixup_ppc_half16:
switch (Modifier) {
default: llvm_unreachable("Unsupported Modifier");
case MCSymbolRefExpr::VK_None:
Type = ELF::R_PPC_REL16;
break;
case MCSymbolRefExpr::VK_PPC_LO:
Type = ELF::R_PPC_REL16_LO;
break;
case MCSymbolRefExpr::VK_PPC_HI:
Type = ELF::R_PPC_REL16_HI;
break;
case MCSymbolRefExpr::VK_PPC_HA:
Type = ELF::R_PPC_REL16_HA;
break;
}
break;
case FK_Data_4:
case FK_PCRel_4:
Type = ELF::R_PPC_REL32;
break;
case FK_Data_8:
case FK_PCRel_8:
Type = ELF::R_PPC64_REL64;
break;
}
} else {
switch ((unsigned)Fixup.getKind()) {
default: llvm_unreachable("invalid fixup kind!");
case PPC::fixup_ppc_br24abs:
Type = ELF::R_PPC_ADDR24;
break;
case PPC::fixup_ppc_brcond14abs:
Type = ELF::R_PPC_ADDR14; // XXX: or BRNTAKEN?_
break;
case PPC::fixup_ppc_half16:
switch (Modifier) {
default: llvm_unreachable("Unsupported Modifier");
case MCSymbolRefExpr::VK_None:
Type = ELF::R_PPC_ADDR16;
break;
case MCSymbolRefExpr::VK_PPC_LO:
Type = ELF::R_PPC_ADDR16_LO;
break;
case MCSymbolRefExpr::VK_PPC_HI:
Type = ELF::R_PPC_ADDR16_HI;
break;
case MCSymbolRefExpr::VK_PPC_HA:
Type = ELF::R_PPC_ADDR16_HA;
break;
case MCSymbolRefExpr::VK_PPC_HIGHER:
Type = ELF::R_PPC64_ADDR16_HIGHER;
break;
case MCSymbolRefExpr::VK_PPC_HIGHERA:
Type = ELF::R_PPC64_ADDR16_HIGHERA;
break;
case MCSymbolRefExpr::VK_PPC_HIGHEST:
Type = ELF::R_PPC64_ADDR16_HIGHEST;
break;
case MCSymbolRefExpr::VK_PPC_HIGHESTA:
Type = ELF::R_PPC64_ADDR16_HIGHESTA;
break;
case MCSymbolRefExpr::VK_GOT:
Type = ELF::R_PPC_GOT16;
break;
case MCSymbolRefExpr::VK_PPC_GOT_LO:
Type = ELF::R_PPC_GOT16_LO;
break;
case MCSymbolRefExpr::VK_PPC_GOT_HI:
Type = ELF::R_PPC_GOT16_HI;
break;
case MCSymbolRefExpr::VK_PPC_GOT_HA:
Type = ELF::R_PPC_GOT16_HA;
break;
case MCSymbolRefExpr::VK_PPC_TOC:
Type = ELF::R_PPC64_TOC16;
break;
case MCSymbolRefExpr::VK_PPC_TOC_LO:
Type = ELF::R_PPC64_TOC16_LO;
break;
case MCSymbolRefExpr::VK_PPC_TOC_HI:
Type = ELF::R_PPC64_TOC16_HI;
break;
case MCSymbolRefExpr::VK_PPC_TOC_HA:
Type = ELF::R_PPC64_TOC16_HA;
break;
case MCSymbolRefExpr::VK_PPC_TPREL:
Type = ELF::R_PPC_TPREL16;
break;
case MCSymbolRefExpr::VK_PPC_TPREL_LO:
Type = ELF::R_PPC_TPREL16_LO;
break;
case MCSymbolRefExpr::VK_PPC_TPREL_HI:
Type = ELF::R_PPC_TPREL16_HI;
break;
case MCSymbolRefExpr::VK_PPC_TPREL_HA:
Type = ELF::R_PPC_TPREL16_HA;
break;
case MCSymbolRefExpr::VK_PPC_TPREL_HIGHER:
Type = ELF::R_PPC64_TPREL16_HIGHER;
break;
case MCSymbolRefExpr::VK_PPC_TPREL_HIGHERA:
Type = ELF::R_PPC64_TPREL16_HIGHERA;
break;
case MCSymbolRefExpr::VK_PPC_TPREL_HIGHEST:
Type = ELF::R_PPC64_TPREL16_HIGHEST;
break;
case MCSymbolRefExpr::VK_PPC_TPREL_HIGHESTA:
Type = ELF::R_PPC64_TPREL16_HIGHESTA;
break;
case MCSymbolRefExpr::VK_PPC_DTPREL:
Type = ELF::R_PPC64_DTPREL16;
break;
case MCSymbolRefExpr::VK_PPC_DTPREL_LO:
Type = ELF::R_PPC64_DTPREL16_LO;
break;
case MCSymbolRefExpr::VK_PPC_DTPREL_HI:
Type = ELF::R_PPC64_DTPREL16_HI;
break;
case MCSymbolRefExpr::VK_PPC_DTPREL_HA:
Type = ELF::R_PPC64_DTPREL16_HA;
break;
case MCSymbolRefExpr::VK_PPC_DTPREL_HIGHER:
Type = ELF::R_PPC64_DTPREL16_HIGHER;
break;
case MCSymbolRefExpr::VK_PPC_DTPREL_HIGHERA:
Type = ELF::R_PPC64_DTPREL16_HIGHERA;
break;
case MCSymbolRefExpr::VK_PPC_DTPREL_HIGHEST:
Type = ELF::R_PPC64_DTPREL16_HIGHEST;
break;
case MCSymbolRefExpr::VK_PPC_DTPREL_HIGHESTA:
Type = ELF::R_PPC64_DTPREL16_HIGHESTA;
break;
case MCSymbolRefExpr::VK_PPC_GOT_TLSGD:
if (is64Bit())
Type = ELF::R_PPC64_GOT_TLSGD16;
else
Type = ELF::R_PPC_GOT_TLSGD16;
break;
case MCSymbolRefExpr::VK_PPC_GOT_TLSGD_LO:
Type = ELF::R_PPC64_GOT_TLSGD16_LO;
break;
case MCSymbolRefExpr::VK_PPC_GOT_TLSGD_HI:
Type = ELF::R_PPC64_GOT_TLSGD16_HI;
break;
case MCSymbolRefExpr::VK_PPC_GOT_TLSGD_HA:
Type = ELF::R_PPC64_GOT_TLSGD16_HA;
break;
case MCSymbolRefExpr::VK_PPC_GOT_TLSLD:
if (is64Bit())
Type = ELF::R_PPC64_GOT_TLSLD16;
else
Type = ELF::R_PPC_GOT_TLSLD16;
break;
case MCSymbolRefExpr::VK_PPC_GOT_TLSLD_LO:
Type = ELF::R_PPC64_GOT_TLSLD16_LO;
break;
case MCSymbolRefExpr::VK_PPC_GOT_TLSLD_HI:
Type = ELF::R_PPC64_GOT_TLSLD16_HI;
break;
case MCSymbolRefExpr::VK_PPC_GOT_TLSLD_HA:
Type = ELF::R_PPC64_GOT_TLSLD16_HA;
break;
case MCSymbolRefExpr::VK_PPC_GOT_TPREL:
/* We don't have R_PPC64_GOT_TPREL16, but since GOT offsets
are always 4-aligned, we can use R_PPC64_GOT_TPREL16_DS. */
Type = ELF::R_PPC64_GOT_TPREL16_DS;
break;
case MCSymbolRefExpr::VK_PPC_GOT_TPREL_LO:
/* We don't have R_PPC64_GOT_TPREL16_LO, but since GOT offsets
are always 4-aligned, we can use R_PPC64_GOT_TPREL16_LO_DS. */
Type = ELF::R_PPC64_GOT_TPREL16_LO_DS;
break;
case MCSymbolRefExpr::VK_PPC_GOT_TPREL_HI:
Type = ELF::R_PPC64_GOT_TPREL16_HI;
break;
case MCSymbolRefExpr::VK_PPC_GOT_DTPREL:
/* We don't have R_PPC64_GOT_DTPREL16, but since GOT offsets
are always 4-aligned, we can use R_PPC64_GOT_DTPREL16_DS. */
Type = ELF::R_PPC64_GOT_DTPREL16_DS;
break;
case MCSymbolRefExpr::VK_PPC_GOT_DTPREL_LO:
/* We don't have R_PPC64_GOT_DTPREL16_LO, but since GOT offsets
are always 4-aligned, we can use R_PPC64_GOT_DTPREL16_LO_DS. */
Type = ELF::R_PPC64_GOT_DTPREL16_LO_DS;
break;
case MCSymbolRefExpr::VK_PPC_GOT_TPREL_HA:
Type = ELF::R_PPC64_GOT_TPREL16_HA;
break;
case MCSymbolRefExpr::VK_PPC_GOT_DTPREL_HI:
Type = ELF::R_PPC64_GOT_DTPREL16_HI;
break;
case MCSymbolRefExpr::VK_PPC_GOT_DTPREL_HA:
Type = ELF::R_PPC64_GOT_DTPREL16_HA;
break;
}
break;
case PPC::fixup_ppc_half16ds:
switch (Modifier) {
default: llvm_unreachable("Unsupported Modifier");
case MCSymbolRefExpr::VK_None:
Type = ELF::R_PPC64_ADDR16_DS;
break;
case MCSymbolRefExpr::VK_PPC_LO:
Type = ELF::R_PPC64_ADDR16_LO_DS;
break;
case MCSymbolRefExpr::VK_GOT:
Type = ELF::R_PPC64_GOT16_DS;
break;
case MCSymbolRefExpr::VK_PPC_GOT_LO:
Type = ELF::R_PPC64_GOT16_LO_DS;
break;
case MCSymbolRefExpr::VK_PPC_TOC:
Type = ELF::R_PPC64_TOC16_DS;
break;
case MCSymbolRefExpr::VK_PPC_TOC_LO:
Type = ELF::R_PPC64_TOC16_LO_DS;
break;
case MCSymbolRefExpr::VK_PPC_TPREL:
Type = ELF::R_PPC64_TPREL16_DS;
break;
case MCSymbolRefExpr::VK_PPC_TPREL_LO:
Type = ELF::R_PPC64_TPREL16_LO_DS;
break;
case MCSymbolRefExpr::VK_PPC_DTPREL:
Type = ELF::R_PPC64_DTPREL16_DS;
break;
case MCSymbolRefExpr::VK_PPC_DTPREL_LO:
Type = ELF::R_PPC64_DTPREL16_LO_DS;
break;
case MCSymbolRefExpr::VK_PPC_GOT_TPREL:
Type = ELF::R_PPC64_GOT_TPREL16_DS;
break;
case MCSymbolRefExpr::VK_PPC_GOT_TPREL_LO:
Type = ELF::R_PPC64_GOT_TPREL16_LO_DS;
break;
case MCSymbolRefExpr::VK_PPC_GOT_DTPREL:
Type = ELF::R_PPC64_GOT_DTPREL16_DS;
break;
case MCSymbolRefExpr::VK_PPC_GOT_DTPREL_LO:
Type = ELF::R_PPC64_GOT_DTPREL16_LO_DS;
break;
}
break;
case PPC::fixup_ppc_nofixup:
switch (Modifier) {
default: llvm_unreachable("Unsupported Modifier");
case MCSymbolRefExpr::VK_PPC_TLSGD:
if (is64Bit())
Type = ELF::R_PPC64_TLSGD;
else
Type = ELF::R_PPC_TLSGD;
break;
case MCSymbolRefExpr::VK_PPC_TLSLD:
if (is64Bit())
Type = ELF::R_PPC64_TLSLD;
else
Type = ELF::R_PPC_TLSLD;
break;
case MCSymbolRefExpr::VK_PPC_TLS:
if (is64Bit())
Type = ELF::R_PPC64_TLS;
else
Type = ELF::R_PPC_TLS;
break;
}
break;
case FK_Data_8:
switch (Modifier) {
default: llvm_unreachable("Unsupported Modifier");
case MCSymbolRefExpr::VK_PPC_TOCBASE:
Type = ELF::R_PPC64_TOC;
break;
case MCSymbolRefExpr::VK_None:
Type = ELF::R_PPC64_ADDR64;
break;
case MCSymbolRefExpr::VK_PPC_DTPMOD:
Type = ELF::R_PPC64_DTPMOD64;
break;
case MCSymbolRefExpr::VK_PPC_TPREL:
Type = ELF::R_PPC64_TPREL64;
break;
case MCSymbolRefExpr::VK_PPC_DTPREL:
Type = ELF::R_PPC64_DTPREL64;
break;
}
break;
case FK_Data_4:
Type = ELF::R_PPC_ADDR32;
break;
case FK_Data_2:
Type = ELF::R_PPC_ADDR16;
break;
}
}
return Type;
}
bool PPCELFObjectWriter::needsRelocateWithSymbol(const MCSymbolData &SD,
unsigned Type) const {
switch (Type) {
default:
return false;
case ELF::R_PPC_REL24:
// If the target symbol has a local entry point, we must keep the
// target symbol to preserve that information for the linker.
// The "other" values are stored in the last 6 bits of the second byte.
// The traditional defines for STO values assume the full byte and thus
// the shift to pack it.
unsigned Other = MCELF::getOther(SD) << 2;
return (Other & ELF::STO_PPC64_LOCAL_MASK) != 0;
}
}
MCObjectWriter *llvm::createPPCELFObjectWriter(raw_ostream &OS,
bool Is64Bit,
bool IsLittleEndian,
uint8_t OSABI) {
MCELFObjectTargetWriter *MOTW = new PPCELFObjectWriter(Is64Bit, OSABI);
return createELFObjectWriter(MOTW, OS, IsLittleEndian);
}