llvm-6502/lib/Target/PowerPC/MCTargetDesc/PPCELFObjectWriter.cpp
Rafael Espindola 930ca98433 Fix pr19645.
The fix itself is fairly simple: move getAccessVariant to MCValue so that we
replace the old weak expression evaluation with the far more general
EvaluateAsRelocatable.

This then requires that EvaluateAsRelocatable stop when it finds a non
trivial reference kind. And that in turn requires the ELF writer to look
harder for weak references.

Last but not least, this found a case where we were being bug by bug
compatible with gas and accepting an invalid input. I reported pr19647
to track it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207920 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-03 19:57:04 +00:00

389 lines
13 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/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);
virtual ~PPCELFObjectWriter();
protected:
virtual unsigned getRelocTypeInner(const MCValue &Target,
const MCFixup &Fixup,
bool IsPCRel) const;
unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
bool IsPCRel) const override;
};
}
PPCELFObjectWriter::PPCELFObjectWriter(bool Is64Bit, uint8_t OSABI)
: MCELFObjectTargetWriter(Is64Bit, OSABI,
Is64Bit ? ELF::EM_PPC64 : ELF::EM_PPC,
/*HasRelocationAddend*/ true) {}
PPCELFObjectWriter::~PPCELFObjectWriter() {
}
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::getRelocTypeInner(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:
Type = ELF::R_PPC_REL24;
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:
Type = ELF::R_PPC64_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:
Type = ELF::R_PPC64_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:
Type = ELF::R_PPC64_TLSGD;
break;
case MCSymbolRefExpr::VK_PPC_TLSLD:
Type = ELF::R_PPC64_TLSLD;
break;
case MCSymbolRefExpr::VK_PPC_TLS:
Type = ELF::R_PPC64_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;
}
unsigned PPCELFObjectWriter::GetRelocType(const MCValue &Target,
const MCFixup &Fixup,
bool IsPCRel) const {
return getRelocTypeInner(Target, Fixup, IsPCRel);
}
MCObjectWriter *llvm::createPPCELFObjectWriter(raw_ostream &OS,
bool Is64Bit,
bool IsLittleEndian,
uint8_t OSABI) {
MCELFObjectTargetWriter *MOTW = new PPCELFObjectWriter(Is64Bit, OSABI);
return createELFObjectWriter(MOTW, OS, IsLittleEndian);
}