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-rw-r--r--gnu/llvm/lib/Target/ARM/MCTargetDesc/ARMMachObjectWriter.cpp511
1 files changed, 0 insertions, 511 deletions
diff --git a/gnu/llvm/lib/Target/ARM/MCTargetDesc/ARMMachObjectWriter.cpp b/gnu/llvm/lib/Target/ARM/MCTargetDesc/ARMMachObjectWriter.cpp
deleted file mode 100644
index 0ced8195790..00000000000
--- a/gnu/llvm/lib/Target/ARM/MCTargetDesc/ARMMachObjectWriter.cpp
+++ /dev/null
@@ -1,511 +0,0 @@
-//===-- ARMMachObjectWriter.cpp - ARM Mach Object Writer ------------------===//
-//
-// The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-
-#include "MCTargetDesc/ARMBaseInfo.h"
-#include "MCTargetDesc/ARMFixupKinds.h"
-#include "MCTargetDesc/ARMMCTargetDesc.h"
-#include "llvm/ADT/Twine.h"
-#include "llvm/BinaryFormat/MachO.h"
-#include "llvm/MC/MCAsmLayout.h"
-#include "llvm/MC/MCAssembler.h"
-#include "llvm/MC/MCContext.h"
-#include "llvm/MC/MCExpr.h"
-#include "llvm/MC/MCFixup.h"
-#include "llvm/MC/MCFixupKindInfo.h"
-#include "llvm/MC/MCMachObjectWriter.h"
-#include "llvm/MC/MCSection.h"
-#include "llvm/MC/MCValue.h"
-#include "llvm/Support/ErrorHandling.h"
-#include "llvm/Support/ScopedPrinter.h"
-
-using namespace llvm;
-
-namespace {
-class ARMMachObjectWriter : public MCMachObjectTargetWriter {
- void RecordARMScatteredRelocation(MachObjectWriter *Writer,
- const MCAssembler &Asm,
- const MCAsmLayout &Layout,
- const MCFragment *Fragment,
- const MCFixup &Fixup,
- MCValue Target,
- unsigned Type,
- unsigned Log2Size,
- uint64_t &FixedValue);
- void RecordARMScatteredHalfRelocation(MachObjectWriter *Writer,
- const MCAssembler &Asm,
- const MCAsmLayout &Layout,
- const MCFragment *Fragment,
- const MCFixup &Fixup, MCValue Target,
- uint64_t &FixedValue);
-
- bool requiresExternRelocation(MachObjectWriter *Writer,
- const MCAssembler &Asm,
- const MCFragment &Fragment, unsigned RelocType,
- const MCSymbol &S, uint64_t FixedValue);
-
-public:
- ARMMachObjectWriter(bool Is64Bit, uint32_t CPUType, uint32_t CPUSubtype)
- : MCMachObjectTargetWriter(Is64Bit, CPUType, CPUSubtype) {}
-
- void recordRelocation(MachObjectWriter *Writer, MCAssembler &Asm,
- const MCAsmLayout &Layout, const MCFragment *Fragment,
- const MCFixup &Fixup, MCValue Target,
- uint64_t &FixedValue) override;
-};
-}
-
-static bool getARMFixupKindMachOInfo(unsigned Kind, unsigned &RelocType,
- unsigned &Log2Size) {
- RelocType = unsigned(MachO::ARM_RELOC_VANILLA);
- Log2Size = ~0U;
-
- switch (Kind) {
- default:
- return false;
-
- case FK_Data_1:
- Log2Size = llvm::Log2_32(1);
- return true;
- case FK_Data_2:
- Log2Size = llvm::Log2_32(2);
- return true;
- case FK_Data_4:
- Log2Size = llvm::Log2_32(4);
- return true;
- case FK_Data_8:
- Log2Size = llvm::Log2_32(8);
- return true;
-
- // These fixups are expected to always be resolvable at assembly time and
- // have no relocations supported.
- case ARM::fixup_arm_ldst_pcrel_12:
- case ARM::fixup_arm_pcrel_10:
- case ARM::fixup_arm_adr_pcrel_12:
- case ARM::fixup_arm_thumb_br:
- return false;
-
- // Handle 24-bit branch kinds.
- case ARM::fixup_arm_condbranch:
- case ARM::fixup_arm_uncondbranch:
- case ARM::fixup_arm_uncondbl:
- case ARM::fixup_arm_condbl:
- case ARM::fixup_arm_blx:
- RelocType = unsigned(MachO::ARM_RELOC_BR24);
- // Report as 'long', even though that is not quite accurate.
- Log2Size = llvm::Log2_32(4);
- return true;
-
- case ARM::fixup_t2_uncondbranch:
- case ARM::fixup_arm_thumb_bl:
- case ARM::fixup_arm_thumb_blx:
- RelocType = unsigned(MachO::ARM_THUMB_RELOC_BR22);
- Log2Size = llvm::Log2_32(4);
- return true;
-
- // For movw/movt r_type relocations they always have a pair following them and
- // the r_length bits are used differently. The encoding of the r_length is as
- // follows:
- // low bit of r_length:
- // 0 - :lower16: for movw instructions
- // 1 - :upper16: for movt instructions
- // high bit of r_length:
- // 0 - arm instructions
- // 1 - thumb instructions
- case ARM::fixup_arm_movt_hi16:
- RelocType = unsigned(MachO::ARM_RELOC_HALF);
- Log2Size = 1;
- return true;
- case ARM::fixup_t2_movt_hi16:
- RelocType = unsigned(MachO::ARM_RELOC_HALF);
- Log2Size = 3;
- return true;
-
- case ARM::fixup_arm_movw_lo16:
- RelocType = unsigned(MachO::ARM_RELOC_HALF);
- Log2Size = 0;
- return true;
- case ARM::fixup_t2_movw_lo16:
- RelocType = unsigned(MachO::ARM_RELOC_HALF);
- Log2Size = 2;
- return true;
- }
-}
-
-void ARMMachObjectWriter::
-RecordARMScatteredHalfRelocation(MachObjectWriter *Writer,
- const MCAssembler &Asm,
- const MCAsmLayout &Layout,
- const MCFragment *Fragment,
- const MCFixup &Fixup,
- MCValue Target,
- uint64_t &FixedValue) {
- uint32_t FixupOffset = Layout.getFragmentOffset(Fragment)+Fixup.getOffset();
-
- if (FixupOffset & 0xff000000) {
- Asm.getContext().reportError(Fixup.getLoc(),
- "can not encode offset '0x" +
- to_hexString(FixupOffset) +
- "' in resulting scattered relocation.");
- return;
- }
-
- unsigned IsPCRel = Writer->isFixupKindPCRel(Asm, Fixup.getKind());
- unsigned Type = MachO::ARM_RELOC_HALF;
-
- // See <reloc.h>.
- const MCSymbol *A = &Target.getSymA()->getSymbol();
-
- if (!A->getFragment()) {
- Asm.getContext().reportError(Fixup.getLoc(),
- "symbol '" + A->getName() +
- "' can not be undefined in a subtraction expression");
- return;
- }
-
- uint32_t Value = Writer->getSymbolAddress(*A, Layout);
- uint32_t Value2 = 0;
- uint64_t SecAddr = Writer->getSectionAddress(A->getFragment()->getParent());
- FixedValue += SecAddr;
-
- if (const MCSymbolRefExpr *B = Target.getSymB()) {
- const MCSymbol *SB = &B->getSymbol();
-
- if (!SB->getFragment()) {
- Asm.getContext().reportError(Fixup.getLoc(),
- "symbol '" + B->getSymbol().getName() +
- "' can not be undefined in a subtraction expression");
- return;
- }
-
- // Select the appropriate difference relocation type.
- Type = MachO::ARM_RELOC_HALF_SECTDIFF;
- Value2 = Writer->getSymbolAddress(B->getSymbol(), Layout);
- FixedValue -= Writer->getSectionAddress(SB->getFragment()->getParent());
- }
-
- // Relocations are written out in reverse order, so the PAIR comes first.
- // ARM_RELOC_HALF and ARM_RELOC_HALF_SECTDIFF abuse the r_length field:
- //
- // For these two r_type relocations they always have a pair following them and
- // the r_length bits are used differently. The encoding of the r_length is as
- // follows:
- // low bit of r_length:
- // 0 - :lower16: for movw instructions
- // 1 - :upper16: for movt instructions
- // high bit of r_length:
- // 0 - arm instructions
- // 1 - thumb instructions
- // the other half of the relocated expression is in the following pair
- // relocation entry in the low 16 bits of r_address field.
- unsigned ThumbBit = 0;
- unsigned MovtBit = 0;
- switch ((unsigned)Fixup.getKind()) {
- default: break;
- case ARM::fixup_arm_movt_hi16:
- MovtBit = 1;
- // The thumb bit shouldn't be set in the 'other-half' bit of the
- // relocation, but it will be set in FixedValue if the base symbol
- // is a thumb function. Clear it out here.
- if (Asm.isThumbFunc(A))
- FixedValue &= 0xfffffffe;
- break;
- case ARM::fixup_t2_movt_hi16:
- if (Asm.isThumbFunc(A))
- FixedValue &= 0xfffffffe;
- MovtBit = 1;
- LLVM_FALLTHROUGH;
- case ARM::fixup_t2_movw_lo16:
- ThumbBit = 1;
- break;
- }
-
- if (Type == MachO::ARM_RELOC_HALF_SECTDIFF) {
- uint32_t OtherHalf = MovtBit
- ? (FixedValue & 0xffff) : ((FixedValue & 0xffff0000) >> 16);
-
- MachO::any_relocation_info MRE;
- MRE.r_word0 = ((OtherHalf << 0) |
- (MachO::ARM_RELOC_PAIR << 24) |
- (MovtBit << 28) |
- (ThumbBit << 29) |
- (IsPCRel << 30) |
- MachO::R_SCATTERED);
- MRE.r_word1 = Value2;
- Writer->addRelocation(nullptr, Fragment->getParent(), MRE);
- }
-
- MachO::any_relocation_info MRE;
- MRE.r_word0 = ((FixupOffset << 0) |
- (Type << 24) |
- (MovtBit << 28) |
- (ThumbBit << 29) |
- (IsPCRel << 30) |
- MachO::R_SCATTERED);
- MRE.r_word1 = Value;
- Writer->addRelocation(nullptr, Fragment->getParent(), MRE);
-}
-
-void ARMMachObjectWriter::RecordARMScatteredRelocation(MachObjectWriter *Writer,
- const MCAssembler &Asm,
- const MCAsmLayout &Layout,
- const MCFragment *Fragment,
- const MCFixup &Fixup,
- MCValue Target,
- unsigned Type,
- unsigned Log2Size,
- uint64_t &FixedValue) {
- uint32_t FixupOffset = Layout.getFragmentOffset(Fragment)+Fixup.getOffset();
-
- if (FixupOffset & 0xff000000) {
- Asm.getContext().reportError(Fixup.getLoc(),
- "can not encode offset '0x" +
- to_hexString(FixupOffset) +
- "' in resulting scattered relocation.");
- return;
- }
-
- unsigned IsPCRel = Writer->isFixupKindPCRel(Asm, Fixup.getKind());
-
- // See <reloc.h>.
- const MCSymbol *A = &Target.getSymA()->getSymbol();
-
- if (!A->getFragment()) {
- Asm.getContext().reportError(Fixup.getLoc(),
- "symbol '" + A->getName() +
- "' can not be undefined in a subtraction expression");
- return;
- }
-
- uint32_t Value = Writer->getSymbolAddress(*A, Layout);
- uint64_t SecAddr = Writer->getSectionAddress(A->getFragment()->getParent());
- FixedValue += SecAddr;
- uint32_t Value2 = 0;
-
- if (const MCSymbolRefExpr *B = Target.getSymB()) {
- assert(Type == MachO::ARM_RELOC_VANILLA && "invalid reloc for 2 symbols");
- const MCSymbol *SB = &B->getSymbol();
-
- if (!SB->getFragment()) {
- Asm.getContext().reportError(Fixup.getLoc(),
- "symbol '" + B->getSymbol().getName() +
- "' can not be undefined in a subtraction expression");
- return;
- }
-
- // Select the appropriate difference relocation type.
- Type = MachO::ARM_RELOC_SECTDIFF;
- Value2 = Writer->getSymbolAddress(B->getSymbol(), Layout);
- FixedValue -= Writer->getSectionAddress(SB->getFragment()->getParent());
- }
-
- // Relocations are written out in reverse order, so the PAIR comes first.
- if (Type == MachO::ARM_RELOC_SECTDIFF ||
- Type == MachO::ARM_RELOC_LOCAL_SECTDIFF) {
- MachO::any_relocation_info MRE;
- MRE.r_word0 = ((0 << 0) |
- (MachO::ARM_RELOC_PAIR << 24) |
- (Log2Size << 28) |
- (IsPCRel << 30) |
- MachO::R_SCATTERED);
- MRE.r_word1 = Value2;
- Writer->addRelocation(nullptr, Fragment->getParent(), MRE);
- }
-
- MachO::any_relocation_info MRE;
- MRE.r_word0 = ((FixupOffset << 0) |
- (Type << 24) |
- (Log2Size << 28) |
- (IsPCRel << 30) |
- MachO::R_SCATTERED);
- MRE.r_word1 = Value;
- Writer->addRelocation(nullptr, Fragment->getParent(), MRE);
-}
-
-bool ARMMachObjectWriter::requiresExternRelocation(MachObjectWriter *Writer,
- const MCAssembler &Asm,
- const MCFragment &Fragment,
- unsigned RelocType,
- const MCSymbol &S,
- uint64_t FixedValue) {
- // Most cases can be identified purely from the symbol.
- if (Writer->doesSymbolRequireExternRelocation(S))
- return true;
- int64_t Value = (int64_t)FixedValue; // The displacement is signed.
- int64_t Range;
- switch (RelocType) {
- default:
- return false;
- case MachO::ARM_RELOC_BR24:
- // An ARM call might be to a Thumb function, in which case the offset may
- // not be encodable in the instruction and we must use an external
- // relocation that explicitly mentions the function. Not a problem if it's
- // to a temporary "Lwhatever" symbol though, and in fact trying to use an
- // external relocation there causes more issues.
- if (!S.isTemporary())
- return true;
-
- // PC pre-adjustment of 8 for these instructions.
- Value -= 8;
- // ARM BL/BLX has a 25-bit offset.
- Range = 0x1ffffff;
- break;
- case MachO::ARM_THUMB_RELOC_BR22:
- // PC pre-adjustment of 4 for these instructions.
- Value -= 4;
- // Thumb BL/BLX has a 24-bit offset.
- Range = 0xffffff;
- }
- // BL/BLX also use external relocations when an internal relocation
- // would result in the target being out of range. This gives the linker
- // enough information to generate a branch island.
- Value += Writer->getSectionAddress(&S.getSection());
- Value -= Writer->getSectionAddress(Fragment.getParent());
- // If the resultant value would be out of range for an internal relocation,
- // use an external instead.
- if (Value > Range || Value < -(Range + 1))
- return true;
- return false;
-}
-
-void ARMMachObjectWriter::recordRelocation(MachObjectWriter *Writer,
- MCAssembler &Asm,
- const MCAsmLayout &Layout,
- const MCFragment *Fragment,
- const MCFixup &Fixup, MCValue Target,
- uint64_t &FixedValue) {
- unsigned IsPCRel = Writer->isFixupKindPCRel(Asm, Fixup.getKind());
- unsigned Log2Size;
- unsigned RelocType = MachO::ARM_RELOC_VANILLA;
- if (!getARMFixupKindMachOInfo(Fixup.getKind(), RelocType, Log2Size)) {
- // If we failed to get fixup kind info, it's because there's no legal
- // relocation type for the fixup kind. This happens when it's a fixup that's
- // expected to always be resolvable at assembly time and not have any
- // relocations needed.
- Asm.getContext().reportError(Fixup.getLoc(),
- "unsupported relocation on symbol");
- return;
- }
-
- // If this is a difference or a defined symbol plus an offset, then we need a
- // scattered relocation entry. Differences always require scattered
- // relocations.
- if (Target.getSymB()) {
- if (RelocType == MachO::ARM_RELOC_HALF)
- return RecordARMScatteredHalfRelocation(Writer, Asm, Layout, Fragment,
- Fixup, Target, FixedValue);
- return RecordARMScatteredRelocation(Writer, Asm, Layout, Fragment, Fixup,
- Target, RelocType, Log2Size,
- FixedValue);
- }
-
- // Get the symbol data, if any.
- const MCSymbol *A = nullptr;
- if (Target.getSymA())
- A = &Target.getSymA()->getSymbol();
-
- // FIXME: For other platforms, we need to use scattered relocations for
- // internal relocations with offsets. If this is an internal relocation with
- // an offset, it also needs a scattered relocation entry.
- //
- // Is this right for ARM?
- uint32_t Offset = Target.getConstant();
- if (IsPCRel && RelocType == MachO::ARM_RELOC_VANILLA)
- Offset += 1 << Log2Size;
- if (Offset && A && !Writer->doesSymbolRequireExternRelocation(*A) &&
- RelocType != MachO::ARM_RELOC_HALF)
- return RecordARMScatteredRelocation(Writer, Asm, Layout, Fragment, Fixup,
- Target, RelocType, Log2Size,
- FixedValue);
-
- // See <reloc.h>.
- uint32_t FixupOffset = Layout.getFragmentOffset(Fragment)+Fixup.getOffset();
- unsigned Index = 0;
- unsigned Type = 0;
- const MCSymbol *RelSymbol = nullptr;
-
- if (Target.isAbsolute()) { // constant
- // FIXME!
- report_fatal_error("FIXME: relocations to absolute targets "
- "not yet implemented");
- } else {
- // Resolve constant variables.
- if (A->isVariable()) {
- int64_t Res;
- if (A->getVariableValue()->evaluateAsAbsolute(
- Res, Layout, Writer->getSectionAddressMap())) {
- FixedValue = Res;
- return;
- }
- }
-
- // Check whether we need an external or internal relocation.
- if (requiresExternRelocation(Writer, Asm, *Fragment, RelocType, *A,
- FixedValue)) {
- RelSymbol = A;
-
- // For external relocations, make sure to offset the fixup value to
- // compensate for the addend of the symbol address, if it was
- // undefined. This occurs with weak definitions, for example.
- if (!A->isUndefined())
- FixedValue -= Layout.getSymbolOffset(*A);
- } else {
- // The index is the section ordinal (1-based).
- const MCSection &Sec = A->getSection();
- Index = Sec.getOrdinal() + 1;
- FixedValue += Writer->getSectionAddress(&Sec);
- }
- if (IsPCRel)
- FixedValue -= Writer->getSectionAddress(Fragment->getParent());
-
- // The type is determined by the fixup kind.
- Type = RelocType;
- }
-
- // struct relocation_info (8 bytes)
- MachO::any_relocation_info MRE;
- MRE.r_word0 = FixupOffset;
- MRE.r_word1 =
- (Index << 0) | (IsPCRel << 24) | (Log2Size << 25) | (Type << 28);
-
- // Even when it's not a scattered relocation, movw/movt always uses
- // a PAIR relocation.
- if (Type == MachO::ARM_RELOC_HALF) {
- // The entire addend is needed to correctly apply a relocation. One half is
- // extracted from the instruction itself, the other comes from this
- // PAIR. I.e. it's correct that we insert the high bits of the addend in the
- // MOVW case here. relocation entries.
- uint32_t Value = 0;
- switch ((unsigned)Fixup.getKind()) {
- default: break;
- case ARM::fixup_arm_movw_lo16:
- case ARM::fixup_t2_movw_lo16:
- Value = (FixedValue >> 16) & 0xffff;
- break;
- case ARM::fixup_arm_movt_hi16:
- case ARM::fixup_t2_movt_hi16:
- Value = FixedValue & 0xffff;
- break;
- }
- MachO::any_relocation_info MREPair;
- MREPair.r_word0 = Value;
- MREPair.r_word1 = ((0xffffff << 0) |
- (Log2Size << 25) |
- (MachO::ARM_RELOC_PAIR << 28));
-
- Writer->addRelocation(nullptr, Fragment->getParent(), MREPair);
- }
-
- Writer->addRelocation(RelSymbol, Fragment->getParent(), MRE);
-}
-
-std::unique_ptr<MCObjectTargetWriter>
-llvm::createARMMachObjectWriter(bool Is64Bit, uint32_t CPUType,
- uint32_t CPUSubtype) {
- return llvm::make_unique<ARMMachObjectWriter>(Is64Bit, CPUType, CPUSubtype);
-}
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