diff options
Diffstat (limited to 'gold/x86_64.cc')
| -rw-r--r-- | gold/x86_64.cc | 33 |
1 files changed, 28 insertions, 5 deletions
diff --git a/gold/x86_64.cc b/gold/x86_64.cc index c368b039869..dd6c07b9516 100644 --- a/gold/x86_64.cc +++ b/gold/x86_64.cc @@ -4463,6 +4463,14 @@ Target_x86_64<size>::do_ehframe_datarel_base() const // code. We have to change the function so that it always ensures // that it has enough stack space to run some random function. +static const unsigned char cmp_insn_32[] = { 0x64, 0x3b, 0x24, 0x25 }; +static const unsigned char lea_r10_insn_32[] = { 0x44, 0x8d, 0x94, 0x24 }; +static const unsigned char lea_r11_insn_32[] = { 0x44, 0x8d, 0x9c, 0x24 }; + +static const unsigned char cmp_insn_64[] = { 0x64, 0x48, 0x3b, 0x24, 0x25 }; +static const unsigned char lea_r10_insn_64[] = { 0x4c, 0x8d, 0x94, 0x24 }; +static const unsigned char lea_r11_insn_64[] = { 0x4c, 0x8d, 0x9c, 0x24 }; + template<int size> void Target_x86_64<size>::do_calls_non_split(Relobj* object, unsigned int shndx, @@ -4473,25 +4481,40 @@ Target_x86_64<size>::do_calls_non_split(Relobj* object, unsigned int shndx, std::string* from, std::string* to) const { + const char* const cmp_insn = reinterpret_cast<const char*> + (size == 32 ? cmp_insn_32 : cmp_insn_64); + const char* const lea_r10_insn = reinterpret_cast<const char*> + (size == 32 ? lea_r10_insn_32 : lea_r10_insn_64); + const char* const lea_r11_insn = reinterpret_cast<const char*> + (size == 32 ? lea_r11_insn_32 : lea_r11_insn_64); + + const size_t cmp_insn_len = + (size == 32 ? sizeof(cmp_insn_32) : sizeof(cmp_insn_64)); + const size_t lea_r10_insn_len = + (size == 32 ? sizeof(lea_r10_insn_32) : sizeof(lea_r10_insn_64)); + const size_t lea_r11_insn_len = + (size == 32 ? sizeof(lea_r11_insn_32) : sizeof(lea_r11_insn_64)); + const size_t nop_len = (size == 32 ? 7 : 8); + // The function starts with a comparison of the stack pointer and a // field in the TCB. This is followed by a jump. // cmp %fs:NN,%rsp - if (this->match_view(view, view_size, fnoffset, "\x64\x48\x3b\x24\x25", 5) - && fnsize > 9) + if (this->match_view(view, view_size, fnoffset, cmp_insn, cmp_insn_len) + && fnsize > nop_len + 1) { // We will call __morestack if the carry flag is set after this // comparison. We turn the comparison into an stc instruction // and some nops. view[fnoffset] = '\xf9'; - this->set_view_to_nop(view, view_size, fnoffset + 1, 8); + this->set_view_to_nop(view, view_size, fnoffset + 1, nop_len); } // lea NN(%rsp),%r10 // lea NN(%rsp),%r11 else if ((this->match_view(view, view_size, fnoffset, - "\x4c\x8d\x94\x24", 4) + lea_r10_insn, lea_r10_insn_len) || this->match_view(view, view_size, fnoffset, - "\x4c\x8d\x9c\x24", 4)) + lea_r11_insn, lea_r11_insn_len)) && fnsize > 8) { // This is loading an offset from the stack pointer for a |