Patch for gold internal error while fixing erratum 843419.

The crash reason is that the insn to be moved to stub may be a
relocation spot, so instead of placing the origin insn (that is insn
before-relocation) to the stub, I have to place the relocated one.
Note the relocation involved is non-pc-relative, so it is safe to move
the relocated insn.

gold/ChangeLog:
2015-06-29  Han Shen  <shenhan@google.com>

    * AArch64.cc (Erratum_stub::Insn_utilities): New typedef.
    (Erratum_stub::update_erratum_insn): New method.
    (Stub_table::relocate_stubs): Modified to place relocated insn.
    (AArch64_relobj::fix_errata): Modified gold_assert.
This commit is contained in:
Han Shen 2015-06-16 15:00:58 -07:00
parent 06b3fd23bf
commit 56b06706eb
2 changed files with 57 additions and 5 deletions

View File

@ -1,3 +1,12 @@
2015-06-29 Han Shen <shenhan@google.com>
Patch for erratum 843419 internal error.
* AArch64.cc (Erratum_stub::Insn_utilities): New typedef.
(Erratum_stub::update_erratum_insn): New method.
(Stub_table::relocate_stubs): Modified to place relocated insn.
(AArch64_relobj::fix_errata): Modified gold_assert.
2015-06-12 Han Shen <shenhan@google.com>
Fix erratum 835769.

View File

@ -894,6 +894,7 @@ class Erratum_stub : public Stub_base<size, big_endian>
public:
typedef AArch64_relobj<size, big_endian> The_aarch64_relobj;
typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
typedef AArch64_insn_utilities<big_endian> Insn_utilities;
typedef typename AArch64_insn_utilities<big_endian>::Insntype Insntype;
static const int STUB_ADDR_ALIGN;
@ -938,6 +939,38 @@ public:
set_erratum_insn(Insntype insn)
{ this->erratum_insn_ = insn; }
// For 843419, the erratum insn is ld/st xt, [xn, #uimm], which may be a
// relocation spot, in this case, the erratum_insn_ recorded at scanning phase
// is no longer the one we want to write out to the stub, update erratum_insn_
// with relocated version. Also note that in this case xn must not be "PC", so
// it is safe to move the erratum insn from the origin place to the stub. For
// 835769, the erratum insn is multiply-accumulate insn, which could not be a
// relocation spot (assertion added though).
void
update_erratum_insn(Insntype insn)
{
gold_assert(this->erratum_insn_ != this->invalid_insn);
switch (this->type())
{
case ST_E_843419:
gold_assert(Insn_utilities::aarch64_ldst_uimm(insn));
gold_assert(Insn_utilities::aarch64_ldst_uimm(this->erratum_insn()));
gold_assert(Insn_utilities::aarch64_rd(insn) ==
Insn_utilities::aarch64_rd(this->erratum_insn()));
gold_assert(Insn_utilities::aarch64_rn(insn) ==
Insn_utilities::aarch64_rn(this->erratum_insn()));
// Update plain ld/st insn with relocated insn.
this->erratum_insn_ = insn;
break;
case ST_E_835769:
gold_assert(insn == this->erratum_insn());
break;
default:
gold_unreachable();
}
}
// Return the address where an erratum must be done.
AArch64_address
erratum_address() const
@ -1417,7 +1450,7 @@ Stub_table<size, big_endian>::add_erratum_stub(The_erratum_stub* stub)
}
// Find if such erratum exists for givein (obj, shndx, sh_offset).
// Find if such erratum exists for given (obj, shndx, sh_offset).
template<int size, bool big_endian>
Erratum_stub<size, big_endian>*
@ -1518,6 +1551,12 @@ relocate_stubs(const The_relocate_info* relinfo,
{
case ST_E_843419:
case ST_E_835769:
// The 1st insn of the erratum could be a relocation spot,
// in this case we need to fix it with
// "(*i)->erratum_insn()".
elfcpp::Swap<32, big_endian>::writeval(
view + (stub_address - this->address()),
(*i)->erratum_insn());
// For the erratum, the 2nd insn is a b-insn to be patched
// (relocated).
stub_b_insn_address = stub_address + 1 * BPI;
@ -1835,13 +1874,17 @@ AArch64_relobj<size, big_endian>::fix_errata(
pview((*pviews)[i]);
// Double check data before fix.
Insntype* ip =
reinterpret_cast<Insntype*>(pview.view + stub->sh_offset());
Insntype insn_to_fix = ip[0];
gold_assert(insn_to_fix == stub->erratum_insn());
gold_assert(pview.address + stub->sh_offset()
== stub->erratum_address());
// Update previously recorded erratum insn with relocated
// version.
Insntype* ip =
reinterpret_cast<Insntype*>(pview.view + stub->sh_offset());
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();