aarch64_ra(Insntype insn)
{ return aarch64_bits(insn, 10, 5); }
+ static bool
+ is_adr(const Insntype insn)
+ { return (insn & 0x9F000000) == 0x10000000; }
+
static bool
is_adrp(const Insntype insn)
{ return (insn & 0x9F000000) == 0x90000000; }
aarch64_rt2(const Insntype insn)
{ return aarch64_bits(insn, 10, 5); }
+ // Encode imm21 into adr. Signed imm21 is in the range of [-1M, 1M).
+ static Insntype
+ aarch64_adr_encode_imm(Insntype adr, int imm21)
+ {
+ gold_assert(is_adr(adr));
+ gold_assert(-(1 << 20) <= imm21 && imm21 < (1 << 20));
+ const int mask19 = (1 << 19) - 1;
+ const int mask2 = 3;
+ adr &= ~((mask19 << 5) | (mask2 << 29));
+ adr |= ((imm21 & mask2) << 29) | (((imm21 >> 2) & mask19) << 5);
+ return adr;
+ }
+
+ // Retrieve encoded adrp 33-bit signed imm value. This value is obtained by
+ // 21-bit signed imm encoded in the insn multiplied by 4k (page size) and
+ // 64-bit sign-extended, resulting in [-4G, 4G) with 12-lsb being 0.
+ static int64_t
+ aarch64_adrp_decode_imm(const Insntype adrp)
+ {
+ const int mask19 = (1 << 19) - 1;
+ const int mask2 = 3;
+ gold_assert(is_adrp(adrp));
+ // 21-bit imm encoded in adrp.
+ uint64_t imm = ((adrp >> 29) & mask2) | (((adrp >> 5) & mask19) << 2);
+ // Retrieve msb of 21-bit-signed imm for sign extension.
+ uint64_t msbt = (imm >> 20) & 1;
+ // Real value is imm multipled by 4k. Value now has 33-bit information.
+ int64_t value = imm << 12;
+ // Sign extend to 64-bit by repeating msbt 31 (64-33) times and merge it
+ // with value.
+ return ((((uint64_t)(1) << 32) - msbt) << 33) | value;
+ }
+
static bool
aarch64_b(const Insntype insn)
{ return (insn & 0xFC000000) == 0x14000000; }
AArch64_address erratum_address_;
}; // End of "Erratum_stub".
+
+// Erratum sub class to wrap additional info needed by 843419. In fixing this
+// erratum, we may choose to replace 'adrp' with 'adr', in this case, we need
+// adrp's code position (two or three insns before erratum insn itself).
+
+template<int size, bool big_endian>
+class E843419_stub : public Erratum_stub<size, big_endian>
+{
+public:
+ typedef typename AArch64_insn_utilities<big_endian>::Insntype Insntype;
+
+ E843419_stub(AArch64_relobj<size, big_endian>* relobj,
+ unsigned int shndx, unsigned int sh_offset,
+ unsigned int adrp_sh_offset)
+ : Erratum_stub<size, big_endian>(relobj, ST_E_843419, shndx, sh_offset),
+ adrp_sh_offset_(adrp_sh_offset)
+ {}
+
+ unsigned int
+ adrp_sh_offset() const
+ { return this->adrp_sh_offset_; }
+
+private:
+ // Section offset of "adrp". (We do not need a "adrp_shndx_" field, because we
+ // can can obtain it from its parent.)
+ const unsigned int adrp_sh_offset_;
+};
+
+
template<int size, bool big_endian>
const int Erratum_stub<size, big_endian>::STUB_ADDR_ALIGN = 4;
void
fix_errata(typename Sized_relobj_file<size, big_endian>::Views* pviews);
+ // Try to fix erratum 843419 in an optimized way. Return true if patch is
+ // applied.
+ bool
+ try_fix_erratum_843419_optimized(
+ The_erratum_stub*,
+ typename Sized_relobj_file<size, big_endian>::View_size&);
+
// Whether a section needs to be scanned for relocation stubs.
bool
section_needs_reloc_stub_scanning(const elfcpp::Shdr<size, big_endian>&,
Insntype insn_to_fix = ip[0];
stub->update_erratum_insn(insn_to_fix);
- // Replace the erratum insn with a branch-to-stub.
- AArch64_address stub_address =
- stub_table->erratum_stub_address(stub);
- unsigned int b_offset = stub_address - stub->erratum_address();
- AArch64_relocate_functions<size, big_endian>::construct_b(
- pview.view + stub->sh_offset(), b_offset & 0xfffffff);
+ // First try to see if erratum is 843419 and if it can be fixed
+ // without using branch-to-stub.
+ if (!try_fix_erratum_843419_optimized(stub, pview))
+ {
+ // Replace the erratum insn with a branch-to-stub.
+ AArch64_address stub_address =
+ stub_table->erratum_stub_address(stub);
+ unsigned int b_offset = stub_address - stub->erratum_address();
+ AArch64_relocate_functions<size, big_endian>::construct_b(
+ pview.view + stub->sh_offset(), b_offset & 0xfffffff);
+ }
++p;
}
}
}
+// This is an optimization for 843419. This erratum requires the sequence begin
+// with 'adrp', when final value calculated by adrp fits in adr, we can just
+// replace 'adrp' with 'adr', so we save 2 jumps per occurrence. (Note, however,
+// in this case, we do not delete the erratum stub (too late to do so), it is
+// merely generated without ever being called.)
+
+template<int size, bool big_endian>
+bool
+AArch64_relobj<size, big_endian>::try_fix_erratum_843419_optimized(
+ The_erratum_stub* stub,
+ typename Sized_relobj_file<size, big_endian>::View_size& pview)
+{
+ if (stub->type() != ST_E_843419)
+ return false;
+
+ typedef AArch64_insn_utilities<big_endian> Insn_utilities;
+ typedef typename elfcpp::Swap<32,big_endian>::Valtype Insntype;
+ E843419_stub<size, big_endian>* e843419_stub =
+ reinterpret_cast<E843419_stub<size, big_endian>*>(stub);
+ AArch64_address pc = pview.address + e843419_stub->adrp_sh_offset();
+ Insntype* adrp_view = reinterpret_cast<Insntype*>(
+ pview.view + e843419_stub->adrp_sh_offset());
+ Insntype adrp_insn = adrp_view[0];
+ gold_assert(Insn_utilities::is_adrp(adrp_insn));
+ // Get adrp 33-bit signed imm value.
+ int64_t adrp_imm = Insn_utilities::
+ aarch64_adrp_decode_imm(adrp_insn);
+ // adrp - final value transferred to target register is calculated as:
+ // PC[11:0] = Zeros(12)
+ // adrp_dest_value = PC + adrp_imm;
+ int64_t adrp_dest_value = (pc & ~((1 << 12) - 1)) + adrp_imm;
+ // adr -final value transferred to target register is calucalted as:
+ // PC + adr_imm
+ // So we have:
+ // PC + adr_imm = adrp_dest_value
+ // ==>
+ // adr_imm = adrp_dest_value - PC
+ int64_t adr_imm = adrp_dest_value - pc;
+ // Check if imm fits in adr (21-bit signed).
+ if (-(1 << 20) <= adr_imm && adr_imm < (1 << 20))
+ {
+ // Convert 'adrp' into 'adr'.
+ Insntype adr_insn = adrp_insn & ((1 << 31) - 1);
+ adr_insn = Insn_utilities::
+ aarch64_adr_encode_imm(adr_insn, adr_imm);
+ elfcpp::Swap<32, big_endian>::writeval(adrp_view, adr_insn);
+ return true;
+ }
+ return false;
+}
+
+
// Relocate sections.
template<int size, bool big_endian>
return this->plt_;
}
- // Helper method to create erratum stubs for ST_E_843419 and ST_E_835769.
+ // Helper method to create erratum stubs for ST_E_843419 and ST_E_835769. For
+ // ST_E_843419, we need an additional field for adrp offset.
void create_erratum_stub(
AArch64_relobj<size, big_endian>* relobj,
unsigned int shndx,
section_size_type erratum_insn_offset,
Address erratum_address,
typename Insn_utilities::Insntype erratum_insn,
- int erratum_type);
+ int erratum_type,
+ unsigned int e843419_adrp_offset=0);
// Return whether this is a 3-insn erratum sequence.
bool is_erratum_843419_sequence(
section_size_type erratum_insn_offset,
Address erratum_address,
typename Insn_utilities::Insntype erratum_insn,
- int erratum_type)
+ int erratum_type,
+ unsigned int e843419_adrp_offset)
{
gold_assert(erratum_type == ST_E_843419 || erratum_type == ST_E_835769);
The_stub_table* stub_table = relobj->stub_table(shndx);
erratum_insn_offset) == NULL)
{
const int BPI = AArch64_insn_utilities<big_endian>::BYTES_PER_INSN;
- The_erratum_stub* stub = new The_erratum_stub(
- relobj, erratum_type, shndx, erratum_insn_offset);
+ The_erratum_stub* stub;
+ if (erratum_type == ST_E_835769)
+ stub = new The_erratum_stub(relobj, erratum_type, shndx,
+ erratum_insn_offset);
+ else if (erratum_type == ST_E_843419)
+ stub = new E843419_stub<size, big_endian>(
+ relobj, shndx, erratum_insn_offset, e843419_adrp_offset);
+ else
+ gold_unreachable();
stub->set_erratum_insn(erratum_insn);
stub->set_erratum_address(erratum_address);
// For erratum ST_E_843419 and ST_E_835769, the destination address is
output_address + offset + insn_offset;
create_erratum_stub(relobj, shndx,
erratum_insn_offset, erratum_address,
- erratum_insn, ST_E_843419);
+ erratum_insn, ST_E_843419,
+ span_start + offset);
}
}
projects / binutils-gdb.git / commitdiff