Given
bar = foo + 4
.long bar
MC would eat the 4. GNU as includes it in the relocation. The rule seems to be
that a variable that defines a symbol is used in the relocation and one that
does not define a symbol is evaluated and the result included in the relocation.
Fixing this unfortunately required some other changes:
* Since the variable is now evaluated, it would prevent the ELF writer from
noticing the weakref marker the elf streamer uses. This patch then replaces
that with a VariantKind in MCSymbolRefExpr.
* Using VariantKind then requires us to look past other VariantKind to see
.weakref bar,foo
call bar@PLT
doing this also fixes
zed = foo +2
call zed@PLT
so that is a good thing.
* Looking past VariantKind means that the relocation selection has to use
the fixup instead of the target.
This is a reboot of the previous fixes for MC. I will watch the sanitizer
buildbot and wait for a build before adding back the previous fixes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204294 91177308-0d34-0410-b5e6-96231b3b80d8
This changes the implementation of local directional labels to use a dedicated
map. With that it can then just use CreateTempSymbol, which is what the rest
of MC uses.
CreateTempSymbol doesn't do a great job at making sure the names are unique
(or being efficient when the names are not needed), but that should probably
be fixed in a followup patch.
This fixes pr18928.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203826 91177308-0d34-0410-b5e6-96231b3b80d8
We were dropping the displacement on the floor if we also had some
immediate offset.
Should fix PR19033.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202774 91177308-0d34-0410-b5e6-96231b3b80d8
Original commits messages:
Add MRMXr/MRMXm form to X86 for use by instructions which treat the 'reg' field of modrm byte as a don't care value. Will allow for simplification of disassembler code.
Simplify a bunch of code by removing the need for the x86 disassembler table builder to know about extended opcodes. The modrm forms are sufficient to convey the information.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201065 91177308-0d34-0410-b5e6-96231b3b80d8
These should end up (in ELF) as R_X86_64_32S relocs, not R_X86_64_32.
Kill the horrid and incomplete special case and FIXME in
EncodeInstruction() and set things up so it can infer the signedness
from the ImmType just like it can the size and whether it's PC-relative.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200495 91177308-0d34-0410-b5e6-96231b3b80d8
Placed the MC variant diagnostics in the wrong directory accidentally. Move
them into their respective architecture specific directories.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200161 91177308-0d34-0410-b5e6-96231b3b80d8
registers in memory addresses that do not match the index register. As it does
for .att_syntax.
rdar://15887380
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199948 91177308-0d34-0410-b5e6-96231b3b80d8
scale factors in memory addresses. As it does for .att_syntax.
It was producing:
Assertion failed: (((Scale == 1 || Scale == 2 || Scale == 4 || Scale == 8)) && "Invalid scale!"), function CreateMem, file /Volumes/SandBox/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp, line 1133.
rdar://14967214
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199942 91177308-0d34-0410-b5e6-96231b3b80d8
This finishes the job started in r198756, and creates separate opcodes for
64-bit vs. 32-bit versions of the rest of the RET instructions too.
LRETL/LRETQ are interesting... I can't see any justification for their
existence in the SDM. There should be no 'LRETL' in 64-bit mode, and no
need for a REX.W prefix for LRETQ. But this is what GAS does, and my
Sandybridge CPU and an Opteron 6376 concur when tested as follows:
asm __volatile__("pushq $0x1234\nmovq $0x33,%rax\nsalq $32,%rax\norq $1f,%rax\npushq %rax\nlretl $8\n1:");
asm __volatile__("pushq $1234\npushq $0x33\npushq $1f\nlretq $8\n1:");
asm __volatile__("pushq $0x33\npushq $1f\nlretq\n1:");
asm __volatile__("pushq $0x1234\npushq $0x33\npushq $1f\nlretq $8\n1:");
cf. PR8592 and commit r118903, which added LRETQ. I only added LRETIQ to
match it.
I don't quite understand how the Intel syntax parsing for ret
instructions is working, despite r154468 allegedly fixing it. Aren't the
explicitly sized 'retw', 'retd' and 'retq' supposed to work? I have at
least made the 'lretq' work with (and indeed *require*) the 'q'.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199106 91177308-0d34-0410-b5e6-96231b3b80d8
The target specific parser should return `false' if the target AsmParser handles
the directive, and `true' if the generic parser should handle the directive.
Many of the target specific directive handlers would `return Error' which does
not follow these semantics. This change simply changes the target specific
routines to conform to the semantis of the ParseDirective correctly.
Conformance to the semantics improves diagnostics emitted for the invalid
directives. X86 is taken as a sample to ensure that multiple diagnostics are
not presented for a single error.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199068 91177308-0d34-0410-b5e6-96231b3b80d8
They do *different* things to %esp, so they are not equivalent.
Rename PUSHi8 to PUSH32i8 and add the missing PUSH16i8.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198761 91177308-0d34-0410-b5e6-96231b3b80d8
We can't do a perfect job here. We *have* to allow (%dx) even in 64-bit
mode, for example, because it might be used for an unofficial form of
the in/out instructions. We actually want to do a better job of validation
*later*. Perhaps *instead* of doing it where we are at the moment.
But for now, doing what validation we *can* do in the place that the code
already has its validation, is an improvement.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198760 91177308-0d34-0410-b5e6-96231b3b80d8
It seems there is no separate instruction class for having AdSize *and*
OpSize bits set, which is required in order to disambiguate between all
these instructions. So add that to the disassembler.
Hm, perhaps we do need an AdSize16 bit after all?
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198759 91177308-0d34-0410-b5e6-96231b3b80d8
Where "where possible" means that it's an immediate value and it's below
0x10000. In fact GAS will either truncate or error with larger values,
and will insist on using the addr32 prefix to get 32-bit addressing. So
perhaps we should do that, in a later patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198758 91177308-0d34-0410-b5e6-96231b3b80d8
JCXZ should have the 0x67 prefix only if we're in 32-bit mode, so make that
appropriately conditional. And JECXZ needs the prefix instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198757 91177308-0d34-0410-b5e6-96231b3b80d8
I couldn't see how to do this sanely without splitting RETQ from RETL.
Eric says: "sad about the inability to roundtrip them now, but...".
I have no idea what that means, but perhaps it wants preserving in the
commit comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198756 91177308-0d34-0410-b5e6-96231b3b80d8
This fixes the bulk of 16-bit output, and the corresponding test case
x86-16.s now looks mostly like the x86-32.s test case that it was
originally based on. A few irrelevant instructions have been dropped,
and there are still some corner cases to be fixed in subsequent patches.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198752 91177308-0d34-0410-b5e6-96231b3b80d8
The 0x66 prefix toggles between 16-bit and 32-bit addressing mode.
So in 32-bit mode it is used to switch to 16-bit addressing mode for the
following instruction, while in 16-bit mode it's the other way round — it's
used to switch to 32-bit mode instead.
Thus, emit the 0x66 prefix byte for OpSize only in 32-bit (and 64-bit) mode,
and introduce a new OpSize16 bit which is used in 16-bit mode instead.
This is just the basic infrastructure for that change; a subsequent patch
will add the new OpSize16 bit to the 32-bit instructions that need it.
Patch from David Woodhouse.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198586 91177308-0d34-0410-b5e6-96231b3b80d8
This is not really expected to work right yet. Mostly because we will
still emit the OpSize (0x66) prefix in all the wrong places, along with
a number of other corner cases. Those will all be fixed in the subsequent
commits.
Patch from David Woodhouse.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198584 91177308-0d34-0410-b5e6-96231b3b80d8
Add some tests to validate correct register selection, including a fix
to an existing test which was requiring the *wrong* output.
Patch from David Woodhouse.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198566 91177308-0d34-0410-b5e6-96231b3b80d8
