//===----------------------------------------------------------------------===//
#include "MCTargetDesc/ARMMCTargetDesc.h"
+#include "MCTargetDesc/ARMAddressingModes.h"
#include "MCTargetDesc/ARMBaseInfo.h"
#include "MCTargetDesc/ARMFixupKinds.h"
-#include "MCTargetDesc/ARMAddressingModes.h"
+#include "llvm/ADT/StringSwitch.h"
+#include "llvm/MC/MCAsmBackend.h"
#include "llvm/MC/MCAssembler.h"
+#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCDirectives.h"
#include "llvm/MC/MCELFObjectWriter.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCObjectWriter.h"
#include "llvm/MC/MCSectionELF.h"
#include "llvm/MC/MCSectionMachO.h"
-#include "llvm/MC/MCAsmBackend.h"
#include "llvm/MC/MCSubtargetInfo.h"
#include "llvm/MC/MCValue.h"
-#include "llvm/Object/MachOFormat.h"
#include "llvm/Support/ELF.h"
#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/MachO.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
void processFixupValue(const MCAssembler &Asm, const MCAsmLayout &Layout,
const MCFixup &Fixup, const MCFragment *DF,
MCValue &Target, uint64_t &Value,
- bool &IsResolved) {
- const MCSymbolRefExpr *A = Target.getSymA();
- // Some fixups to thumb function symbols need the low bit (thumb bit)
- // twiddled.
- if ((unsigned)Fixup.getKind() != ARM::fixup_arm_ldst_pcrel_12 &&
- (unsigned)Fixup.getKind() != ARM::fixup_t2_ldst_pcrel_12 &&
- (unsigned)Fixup.getKind() != ARM::fixup_arm_adr_pcrel_12 &&
- (unsigned)Fixup.getKind() != ARM::fixup_thumb_adr_pcrel_10 &&
- (unsigned)Fixup.getKind() != ARM::fixup_t2_adr_pcrel_12 &&
- (unsigned)Fixup.getKind() != ARM::fixup_arm_thumb_cp) {
- if (A) {
- const MCSymbol &Sym = A->getSymbol().AliasedSymbol();
- if (Asm.isThumbFunc(&Sym))
- Value |= 1;
- }
- }
- // We must always generate a relocation for BL/BLX instructions if we have
- // a symbol to reference, as the linker relies on knowing the destination
- // symbol's thumb-ness to get interworking right.
- if (A && ((unsigned)Fixup.getKind() == ARM::fixup_arm_thumb_blx ||
- (unsigned)Fixup.getKind() == ARM::fixup_arm_thumb_bl ||
- (unsigned)Fixup.getKind() == ARM::fixup_arm_blx ||
- (unsigned)Fixup.getKind() == ARM::fixup_arm_uncondbl ||
- (unsigned)Fixup.getKind() == ARM::fixup_arm_condbl))
- IsResolved = false;
- }
+ bool &IsResolved);
+
+
+ void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
+ uint64_t Value) const;
bool mayNeedRelaxation(const MCInst &Inst) const;
bool fixupNeedsRelaxation(const MCFixup &Fixup,
uint64_t Value,
- const MCInstFragment *DF,
+ const MCRelaxableFragment *DF,
const MCAsmLayout &Layout) const;
void relaxInstruction(const MCInst &Inst, MCInst &Res) const;
switch (Op) {
default: return Op;
case ARM::tBcc: return ARM::t2Bcc;
- case ARM::tLDRpciASM: return ARM::t2LDRpci;
+ case ARM::tLDRpci: return ARM::t2LDRpci;
case ARM::tADR: return ARM::t2ADR;
case ARM::tB: return ARM::t2B;
+ case ARM::tCBZ: return ARM::tHINT;
+ case ARM::tCBNZ: return ARM::tHINT;
}
}
bool ARMAsmBackend::fixupNeedsRelaxation(const MCFixup &Fixup,
uint64_t Value,
- const MCInstFragment *DF,
+ const MCRelaxableFragment *DF,
const MCAsmLayout &Layout) const {
switch ((unsigned)Fixup.getKind()) {
case ARM::fixup_arm_thumb_br: {
int64_t Offset = int64_t(Value) - 4;
return Offset > 1020 || Offset < 0 || Offset & 3;
}
+ case ARM::fixup_arm_thumb_cb:
+ // If we have a Thumb CBZ or CBNZ instruction and its target is the next
+ // instruction it is is actually out of range for the instruction.
+ // It will be changed to a NOP.
+ int64_t Offset = (Value & ~1);
+ return Offset == 2;
}
llvm_unreachable("Unexpected fixup kind in fixupNeedsRelaxation()!");
}
report_fatal_error("unexpected instruction to relax: " + OS.str());
}
- // The instructions we're relaxing have (so far) the same operands.
+ // If we are changing Thumb CBZ or CBNZ instruction to a NOP, aka tHINT, we
+ // have to change the operands too.
+ if ((Inst.getOpcode() == ARM::tCBZ || Inst.getOpcode() == ARM::tCBNZ) &&
+ RelaxedOp == ARM::tHINT) {
+ Res.setOpcode(RelaxedOp);
+ Res.addOperand(MCOperand::CreateImm(0));
+ Res.addOperand(MCOperand::CreateImm(14));
+ Res.addOperand(MCOperand::CreateReg(0));
+ return;
+ }
+
+ // The rest of instructions we're relaxing have the same operands.
// We just need to update to the proper opcode.
Res = Inst;
Res.setOpcode(RelaxedOp);
bool ARMAsmBackend::writeNopData(uint64_t Count, MCObjectWriter *OW) const {
const uint16_t Thumb1_16bitNopEncoding = 0x46c0; // using MOV r8,r8
const uint16_t Thumb2_16bitNopEncoding = 0xbf00; // NOP
- const uint32_t ARMv4_NopEncoding = 0xe1a0000; // using MOV r0,r0
+ const uint32_t ARMv4_NopEncoding = 0xe1a00000; // using MOV r0,r0
const uint32_t ARMv6T2_NopEncoding = 0xe320f000; // NOP
if (isThumb()) {
const uint16_t nopEncoding = hasNOP() ? Thumb2_16bitNopEncoding
return true;
}
-static unsigned adjustFixupValue(unsigned Kind, uint64_t Value) {
+static unsigned adjustFixupValue(const MCFixup &Fixup, uint64_t Value,
+ MCContext *Ctx = NULL) {
+ unsigned Kind = Fixup.getKind();
switch (Kind) {
default:
llvm_unreachable("Unknown fixup kind!");
Value = -Value;
isAdd = false;
}
- assert ((Value < 4096) && "Out of range pc-relative fixup value!");
+ if (Ctx && Value >= 4096)
+ Ctx->FatalError(Fixup.getLoc(), "out of range pc-relative fixup value");
Value |= isAdd << 23;
// Same addressing mode as fixup_arm_pcrel_10,
Value = -Value;
opc = 2; // 0b0010
}
- assert(ARM_AM::getSOImmVal(Value) != -1 &&
- "Out of range pc-relative fixup value!");
+ if (Ctx && ARM_AM::getSOImmVal(Value) == -1)
+ Ctx->FatalError(Fixup.getLoc(), "out of range pc-relative fixup value");
// Encode the immediate and shift the opcode into place.
return ARM_AM::getSOImmVal(Value) | (opc << 21);
}
case ARM::fixup_arm_blx:
// These values don't encode the low two bits since they're always zero.
// Offset by 8 just as above.
+ if (const MCSymbolRefExpr *SRE = dyn_cast<MCSymbolRefExpr>(Fixup.getValue()))
+ if (SRE->getKind() == MCSymbolRefExpr::VK_ARM_TLSCALL)
+ return 0;
return 0xffffff & ((Value - 8) >> 2);
case ARM::fixup_t2_uncondbranch: {
Value = Value - 4;
}
case ARM::fixup_arm_thumb_bl: {
// The value doesn't encode the low bit (always zero) and is offset by
- // four. The value is encoded into disjoint bit positions in the destination
- // opcode. x = unchanged, I = immediate value bit, S = sign extension bit
+ // four. The 32-bit immediate value is encoded as
+ // imm32 = SignExtend(S:I1:I2:imm10:imm11:0)
+ // where I1 = NOT(J1 ^ S) and I2 = NOT(J2 ^ S).
+ // The value is encoded into disjoint bit positions in the destination
+ // opcode. x = unchanged, I = immediate value bit, S = sign extension bit,
+ // J = either J1 or J2 bit
//
- // BL: xxxxxSIIIIIIIIII xxxxxIIIIIIIIIII
+ // BL: xxxxxSIIIIIIIIII xxJxJIIIIIIIIIII
//
// Note that the halfwords are stored high first, low second; so we need
// to transpose the fixup value here to map properly.
- unsigned isNeg = (int64_t(Value - 4) < 0) ? 1 : 0;
+ uint32_t offset = (Value - 4) >> 1;
+ uint32_t signBit = (offset & 0x800000) >> 23;
+ uint32_t I1Bit = (offset & 0x400000) >> 22;
+ uint32_t J1Bit = (I1Bit ^ 0x1) ^ signBit;
+ uint32_t I2Bit = (offset & 0x200000) >> 21;
+ uint32_t J2Bit = (I2Bit ^ 0x1) ^ signBit;
+ uint32_t imm10Bits = (offset & 0x1FF800) >> 11;
+ uint32_t imm11Bits = (offset & 0x000007FF);
+
uint32_t Binary = 0;
- Value = 0x3fffff & ((Value - 4) >> 1);
- Binary = (Value & 0x7ff) << 16; // Low imm11 value.
- Binary |= (Value & 0x1ffc00) >> 11; // High imm10 value.
- Binary |= isNeg << 10; // Sign bit.
+ uint32_t firstHalf = (((uint16_t)signBit << 10) | (uint16_t)imm10Bits);
+ uint32_t secondHalf = (((uint16_t)J1Bit << 13) | ((uint16_t)J2Bit << 11) |
+ (uint16_t)imm11Bits);
+ Binary |= secondHalf << 16;
+ Binary |= firstHalf;
return Binary;
}
case ARM::fixup_arm_thumb_blx: {
// The value doesn't encode the low two bits (always zero) and is offset by
- // four (see fixup_arm_thumb_cp). The value is encoded into disjoint bit
- // positions in the destination opcode. x = unchanged, I = immediate value
- // bit, S = sign extension bit, 0 = zero.
+ // four (see fixup_arm_thumb_cp). The 32-bit immediate value is encoded as
+ // imm32 = SignExtend(S:I1:I2:imm10H:imm10L:00)
+ // where I1 = NOT(J1 ^ S) and I2 = NOT(J2 ^ S).
+ // The value is encoded into disjoint bit positions in the destination
+ // opcode. x = unchanged, I = immediate value bit, S = sign extension bit,
+ // J = either J1 or J2 bit, 0 = zero.
//
- // BLX: xxxxxSIIIIIIIIII xxxxxIIIIIIIIII0
+ // BLX: xxxxxSIIIIIIIIII xxJxJIIIIIIIIII0
//
// Note that the halfwords are stored high first, low second; so we need
// to transpose the fixup value here to map properly.
- unsigned isNeg = (int64_t(Value-4) < 0) ? 1 : 0;
+ uint32_t offset = (Value - 2) >> 2;
+ if (const MCSymbolRefExpr *SRE = dyn_cast<MCSymbolRefExpr>(Fixup.getValue()))
+ if (SRE->getKind() == MCSymbolRefExpr::VK_ARM_TLSCALL)
+ offset = 0;
+ uint32_t signBit = (offset & 0x400000) >> 22;
+ uint32_t I1Bit = (offset & 0x200000) >> 21;
+ uint32_t J1Bit = (I1Bit ^ 0x1) ^ signBit;
+ uint32_t I2Bit = (offset & 0x100000) >> 20;
+ uint32_t J2Bit = (I2Bit ^ 0x1) ^ signBit;
+ uint32_t imm10HBits = (offset & 0xFFC00) >> 10;
+ uint32_t imm10LBits = (offset & 0x3FF);
+
uint32_t Binary = 0;
- Value = 0xfffff & ((Value - 2) >> 2);
- Binary = (Value & 0x3ff) << 17; // Low imm10L value.
- Binary |= (Value & 0xffc00) >> 10; // High imm10H value.
- Binary |= isNeg << 10; // Sign bit.
+ uint32_t firstHalf = (((uint16_t)signBit << 10) | (uint16_t)imm10HBits);
+ uint32_t secondHalf = (((uint16_t)J1Bit << 13) | ((uint16_t)J2Bit << 11) |
+ ((uint16_t)imm10LBits) << 1);
+ Binary |= secondHalf << 16;
+ Binary |= firstHalf;
return Binary;
}
case ARM::fixup_arm_thumb_cp:
isAdd = false;
}
// The value has the low 4 bits encoded in [3:0] and the high 4 in [11:8].
- assert ((Value < 256) && "Out of range pc-relative fixup value!");
+ if (Ctx && Value >= 256)
+ Ctx->FatalError(Fixup.getLoc(), "out of range pc-relative fixup value");
Value = (Value & 0xf) | ((Value & 0xf0) << 4);
return Value | (isAdd << 23);
}
}
// These values don't encode the low two bits since they're always zero.
Value >>= 2;
- assert ((Value < 256) && "Out of range pc-relative fixup value!");
+ if (Ctx && Value >= 256)
+ Ctx->FatalError(Fixup.getLoc(), "out of range pc-relative fixup value");
Value |= isAdd << 23;
// Same addressing mode as fixup_arm_pcrel_10, but with 16-bit halfwords
}
}
-namespace {
-
-// FIXME: This should be in a separate file.
-// ELF is an ELF of course...
-class ELFARMAsmBackend : public ARMAsmBackend {
-public:
- uint8_t OSABI;
- ELFARMAsmBackend(const Target &T, const StringRef TT,
- uint8_t _OSABI)
- : ARMAsmBackend(T, TT), OSABI(_OSABI) { }
-
- void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
- uint64_t Value) const;
-
- MCObjectWriter *createObjectWriter(raw_ostream &OS) const {
- return createARMELFObjectWriter(OS, OSABI);
- }
-};
-
-// FIXME: Raise this to share code between Darwin and ELF.
-void ELFARMAsmBackend::applyFixup(const MCFixup &Fixup, char *Data,
- unsigned DataSize, uint64_t Value) const {
- unsigned NumBytes = 4; // FIXME: 2 for Thumb
- Value = adjustFixupValue(Fixup.getKind(), Value);
- if (!Value) return; // Doesn't change encoding.
-
- unsigned Offset = Fixup.getOffset();
-
- // For each byte of the fragment that the fixup touches, mask in the bits from
- // the fixup value. The Value has been "split up" into the appropriate
- // bitfields above.
- for (unsigned i = 0; i != NumBytes; ++i)
- Data[Offset + i] |= uint8_t((Value >> (i * 8)) & 0xff);
-}
-
-// FIXME: This should be in a separate file.
-class DarwinARMAsmBackend : public ARMAsmBackend {
-public:
- const object::mach::CPUSubtypeARM Subtype;
- DarwinARMAsmBackend(const Target &T, const StringRef TT,
- object::mach::CPUSubtypeARM st)
- : ARMAsmBackend(T, TT), Subtype(st) { }
-
- MCObjectWriter *createObjectWriter(raw_ostream &OS) const {
- return createARMMachObjectWriter(OS, /*Is64Bit=*/false,
- object::mach::CTM_ARM,
- Subtype);
+void ARMAsmBackend::processFixupValue(const MCAssembler &Asm,
+ const MCAsmLayout &Layout,
+ const MCFixup &Fixup,
+ const MCFragment *DF,
+ MCValue &Target, uint64_t &Value,
+ bool &IsResolved) {
+ const MCSymbolRefExpr *A = Target.getSymA();
+ // Some fixups to thumb function symbols need the low bit (thumb bit)
+ // twiddled.
+ if ((unsigned)Fixup.getKind() != ARM::fixup_arm_ldst_pcrel_12 &&
+ (unsigned)Fixup.getKind() != ARM::fixup_t2_ldst_pcrel_12 &&
+ (unsigned)Fixup.getKind() != ARM::fixup_arm_adr_pcrel_12 &&
+ (unsigned)Fixup.getKind() != ARM::fixup_thumb_adr_pcrel_10 &&
+ (unsigned)Fixup.getKind() != ARM::fixup_t2_adr_pcrel_12 &&
+ (unsigned)Fixup.getKind() != ARM::fixup_arm_thumb_cp) {
+ if (A) {
+ const MCSymbol &Sym = A->getSymbol().AliasedSymbol();
+ if (Asm.isThumbFunc(&Sym))
+ Value |= 1;
+ }
}
-
- void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
- uint64_t Value) const;
-
- virtual bool doesSectionRequireSymbols(const MCSection &Section) const {
- return false;
+ // For Thumb1 BL instruction, it is possible to be a long jump between
+ // the basic blocks of the same function. Thus, we would like to resolve
+ // the offset when the destination has the same MCFragment.
+ if (A && (unsigned)Fixup.getKind() == ARM::fixup_arm_thumb_bl) {
+ const MCSymbol &Sym = A->getSymbol().AliasedSymbol();
+ MCSymbolData &SymData = Asm.getSymbolData(Sym);
+ IsResolved = (SymData.getFragment() == DF);
}
-};
+ // We must always generate a relocation for BL/BLX instructions if we have
+ // a symbol to reference, as the linker relies on knowing the destination
+ // symbol's thumb-ness to get interworking right.
+ if (A && ((unsigned)Fixup.getKind() == ARM::fixup_arm_thumb_blx ||
+ (unsigned)Fixup.getKind() == ARM::fixup_arm_blx ||
+ (unsigned)Fixup.getKind() == ARM::fixup_arm_uncondbl ||
+ (unsigned)Fixup.getKind() == ARM::fixup_arm_condbl))
+ IsResolved = false;
+
+ // Try to get the encoded value for the fixup as-if we're mapping it into
+ // the instruction. This allows adjustFixupValue() to issue a diagnostic
+ // if the value aren't invalid.
+ (void)adjustFixupValue(Fixup, Value, &Asm.getContext());
+}
/// getFixupKindNumBytes - The number of bytes the fixup may change.
static unsigned getFixupKindNumBytes(unsigned Kind) {
}
}
-void DarwinARMAsmBackend::applyFixup(const MCFixup &Fixup, char *Data,
- unsigned DataSize, uint64_t Value) const {
+void ARMAsmBackend::applyFixup(const MCFixup &Fixup, char *Data,
+ unsigned DataSize, uint64_t Value) const {
unsigned NumBytes = getFixupKindNumBytes(Fixup.getKind());
- Value = adjustFixupValue(Fixup.getKind(), Value);
+ Value = adjustFixupValue(Fixup, Value);
if (!Value) return; // Doesn't change encoding.
unsigned Offset = Fixup.getOffset();
assert(Offset + NumBytes <= DataSize && "Invalid fixup offset!");
- // For each byte of the fragment that the fixup touches, mask in the
- // bits from the fixup value.
+ // For each byte of the fragment that the fixup touches, mask in the bits from
+ // the fixup value. The Value has been "split up" into the appropriate
+ // bitfields above.
for (unsigned i = 0; i != NumBytes; ++i)
Data[Offset + i] |= uint8_t((Value >> (i * 8)) & 0xff);
}
+namespace {
+
+// FIXME: This should be in a separate file.
+// ELF is an ELF of course...
+class ELFARMAsmBackend : public ARMAsmBackend {
+public:
+ uint8_t OSABI;
+ ELFARMAsmBackend(const Target &T, const StringRef TT,
+ uint8_t _OSABI)
+ : ARMAsmBackend(T, TT), OSABI(_OSABI) { }
+
+ MCObjectWriter *createObjectWriter(raw_ostream &OS) const {
+ return createARMELFObjectWriter(OS, OSABI);
+ }
+};
+
+// FIXME: This should be in a separate file.
+class DarwinARMAsmBackend : public ARMAsmBackend {
+public:
+ const MachO::CPUSubTypeARM Subtype;
+ DarwinARMAsmBackend(const Target &T, const StringRef TT,
+ MachO::CPUSubTypeARM st)
+ : ARMAsmBackend(T, TT), Subtype(st) {
+ HasDataInCodeSupport = true;
+ }
+
+ MCObjectWriter *createObjectWriter(raw_ostream &OS) const {
+ return createARMMachObjectWriter(OS, /*Is64Bit=*/false,
+ MachO::CPU_TYPE_ARM,
+ Subtype);
+ }
+
+ virtual bool doesSectionRequireSymbols(const MCSection &Section) const {
+ return false;
+ }
+};
+
} // end anonymous namespace
-MCAsmBackend *llvm::createARMAsmBackend(const Target &T, StringRef TT) {
+MCAsmBackend *llvm::createARMAsmBackend(const Target &T,
+ const MCRegisterInfo &MRI,
+ StringRef TT, StringRef CPU) {
Triple TheTriple(TT);
- if (TheTriple.isOSDarwin()) {
- if (TheTriple.getArchName() == "armv4t" ||
- TheTriple.getArchName() == "thumbv4t")
- return new DarwinARMAsmBackend(T, TT, object::mach::CSARM_V4T);
- else if (TheTriple.getArchName() == "armv5e" ||
- TheTriple.getArchName() == "thumbv5e")
- return new DarwinARMAsmBackend(T, TT, object::mach::CSARM_V5TEJ);
- else if (TheTriple.getArchName() == "armv6" ||
- TheTriple.getArchName() == "thumbv6")
- return new DarwinARMAsmBackend(T, TT, object::mach::CSARM_V6);
- return new DarwinARMAsmBackend(T, TT, object::mach::CSARM_V7);
+ if (TheTriple.isOSBinFormatMachO()) {
+ MachO::CPUSubTypeARM CS =
+ StringSwitch<MachO::CPUSubTypeARM>(TheTriple.getArchName())
+ .Cases("armv4t", "thumbv4t", MachO::CPU_SUBTYPE_ARM_V4T)
+ .Cases("armv5e", "thumbv5e", MachO::CPU_SUBTYPE_ARM_V5TEJ)
+ .Cases("armv6", "thumbv6", MachO::CPU_SUBTYPE_ARM_V6)
+ .Cases("armv6m", "thumbv6m", MachO::CPU_SUBTYPE_ARM_V6M)
+ .Cases("armv7em", "thumbv7em", MachO::CPU_SUBTYPE_ARM_V7EM)
+ .Cases("armv7k", "thumbv7k", MachO::CPU_SUBTYPE_ARM_V7K)
+ .Cases("armv7m", "thumbv7m", MachO::CPU_SUBTYPE_ARM_V7M)
+ .Cases("armv7s", "thumbv7s", MachO::CPU_SUBTYPE_ARM_V7S)
+ .Default(MachO::CPU_SUBTYPE_ARM_V7);
+
+ return new DarwinARMAsmBackend(T, TT, CS);
}
- if (TheTriple.isOSWindows())
+#if 0
+ // FIXME: Introduce yet another checker but assert(0).
+ if (TheTriple.isOSBinFormatCOFF())
assert(0 && "Windows not supported on ARM");
+#endif
uint8_t OSABI = MCELFObjectTargetWriter::getOSABI(Triple(TT).getOS());
return new ELFARMAsmBackend(T, TT, OSABI);
projects / oota-llvm.git / blobdiff