Having everybody and their uncle reading and writing fields out
of a.code and stubs.code was making assembler work hard. This replaces most
reads with accessors, and all writes with structured friends of
X64SAssembler.
Retry of D848605 which doesn't segfault the open-source build.
Formerly, this change caused the assembler to emit an opsize
prefix before ret instructions taking a 16-bit immediate, which
worked on our machines but caused problems for Travis CI.
There was a confusing comment left in the assembler
that said that we can't encode a decl r32 instruction, because
the opcode is the same as a REX byte. This is untrue in our
assembler, because we use the FF /1 encoding, rather than the
48 one (which is a REX byte and would be a problem).
Some tests were added to show that this is fine.
Formerly, trying to emit a 16-bit instruction, such as
with test_imm16_disp_reg64(...) would actually emit a testl
instead of a testw. This would emit an 8-byte instruction
(ex. 41 f7 45 0e 01 01 00 00) and possibly be testing the wrong
thing. Now, when you emit a word-size instruction, it will prefix
with 66 and use the correct operand size, saving us a byte
(ex. 66 41 f7 45 0e 01 01).
I also converted the instruction emission in ContPreNext to
use the new style assembly emission.
SimpleLableTest used rbx, r10, r11, r15 without saving them,
causing lots of potential issues.
RandomJunk relied on white space at the end of a line - but our
master.emacs is setup to strip trailing space on save. I rewrote
the test to avoid having to remember to override every time.
I was learning from @jdelong and he said that you should use
double quotes for local includes and angle brackets for library
includes. I asked why our code was the way it was, and he said he wanted
to clean it up. I beat him to it :)
Conflicts:
hphp/runtime/base/server/admin_request_handler.cpp
hphp/runtime/vm/named_entity.h
We had the belief that m_type as an int32_t (and in at least one
place, an int64_t) burned in many places. This is going to make any kind of
re-encoding of TypedValues nearly impossible.
Redirect all such accesses via some helpers, so e.g.
a. cmpl(KindOfUninit, base[TVOFF(m_type)]);
becomes
emitCmpTVType(a, KindOfUninit, base[TVOFF(m_type)]);
which may do byte or dword access, depending on m_type's actual size. While
this is motivated by 7pack, I'm planning to route it through trunk to
prevent any more of the old style accesses from cropping up.
This change is mostly for FB internal organizational reasons.
Building is not effected beyond the fact that the target now
lands in hphp/hhvm/hhvm rather than src/hhvm/hhvm.
Paul Bissonnette