This is necessary not only for representing empty ranges, but for handling
multibyte characters in the input. (If the end pointer in a range refers to
a multibyte character, should it point to the beginning or the end of the
character in a char array?) Some of the code in the asm parsers was already
assuming this anyway.
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Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.
Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]
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When an instruction as written requires 32-bit mode and we're assembling
in 64-bit mode, or vice-versa, issue a more specific diagnostic about
what's wrong.
rdar://12700702
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- Add RTM code generation support throught 3 X86 intrinsics:
xbegin()/xend() to start/end a transaction region, and xabort() to abort a
tranaction region
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[register].field
The operator returns the value at the location pointed to by register plus the
offset of field within its structure or union. This patch only handles
immediate fields (i.e., [eax].4). The original displacement has to be a
MCConstantExpr as well.
Part of rdar://12470415 and rdar://12470514
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see the offsetof operator. Previously, we were matching something like MOVrm
in the front-end and later matching MOVrr in the back-end. This change makes
things more consistent. It also fixes cases where we can't match against a
memory operand as the source (test cases coming).
Part of rdar://12470317
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non-zero value as we don't know the actual value at this point. This is
necessary to get the matching correct in some cases. However, the actual value
set as the base register doesn't matter, since we're just matching not emitting.
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a memory operand. Retain this information and then add the sizing directives
to the IR. This allows the backend to do proper instruction selection.
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the interface between the front-end and the MC layer when parsing inline
assembly. Unfortunately, this is too deep into the parsing stack. Specifically,
we're unable to handle target-independent assembly (i.e., assembly directives,
labels, etc.). Note the MatchAndEmitInstruction() isn't the correct
abstraction either. I'll be exposing target-independent hooks shortly, so this
is really just a cleanup.
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of operand is specific to MS-style inline assembly and should not be generated
when parsing normal assembly.
The purpose of the wildcard operands are to allow the AsmParser to match
multiple instructions (i.e., MCInsts) to a given ms-style asm statement. For
the time being the matcher just returns the first match. This patch only
implements wildcard matches for memory operands. Support for register
wildcards will be added in the near future.
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map constraints and MCInst operands to inline asm operands. This replaces the
getMCInstOperandNum() function.
The logic to determine the constraints are not in place, so we still default to
a register constraint (i.e., "r"). Also, we no longer build the MCInst but
rather return just the opcode to get the MCInstrDesc.
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gas accepts this and it seems to be common enough to be worth supporting. This
doesn't affect the parsing of reg operands outside of .cfi directives.
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the NumMCOperands argument to the GetMCInstOperandNum() function that is set
to the number of MCOperands this asm operand mapped to.
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MatchInstructionImpl() function.
These values are used by the ConvertToMCInst() function to index into the
ConversionTable. The values are also needed to call the GetMCInstOperandNum()
function.
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Assertion failed: (Start.isValid() == End.isValid() && "Start and end should
either both be valid or both be invalid!")
when parsing inline asm. SMLoc assumes that the first char * in the source is
invalid. However, when parsing an inline asm the mnemonic is at this location.
I don't want to change SMLoc, so use a trivial workaround.
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this is the index of the operand that failed to match.
Note: This may cause a buildbot failure due to an API mismatch in clang. Should
recover with my next commit to clang.
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This new API will be used by clang to parse ms-style inline asms.
One goal of this project is to use this style of inline asm for targets other
then x86. Therefore, this API needs to be implemented for non-x86 targets at
some point in the future.
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instruction's destination operand like it does for the source operand.
Also fix a typo in the comment for X86AsmParser::isSrcOp().
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rdar://10873652
As part of this I updated the llvm-mc disassembler C API to always call the
SymbolLookUp call back even if there is no getOpInfo call back. If there is a
getOpInfo call back that is tried first and then if that gets no information
then the SymbolLookUp is called. I also made the code more robust by
memset(3)'ing to zero the LLVMOpInfo1 struct before then setting
SymbolicOp.Value before for the call to getOpInfo. And also don't use any
values from the LLVMOpInfo1 struct if getOpInfo returns 0. And also don't
use any of the ReferenceType or ReferenceName values from SymbolLookUp if it
returns NULL. rdar://10873563 and rdar://10873683
For the X86 target also fixed bugs so the annotations get printed.
Also fixed a few places in the ARM target that was not producing symbolic
operands for some instructions. rdar://10878166
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In att style asm syntax memory operand size is derived from suffix attached with mnemonic. In intel style asm syntax it is part of memory operand hence predicate method check is required to select appropriate instruction.
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the X86 asmparser to produce ranges in the one case that was annoying me, for example:
test.s:10:15: error: invalid operand for instruction
movl 0(%rax), 0(%edx)
^~~~~~~
It should be straight-forward to enhance filecheck, tblgen, and/or the .ll parser to use
ranges where appropriate if someone is interested.
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Allow a target assembly parser to do context sensitive constraint checking
on a potential instruction match. This will be used, for example, to handle
Thumb2 IT block parsing.
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specified in the same file that the library itself is created. This is
more idiomatic for CMake builds, and also allows us to correctly specify
dependencies that are missed due to bugs in the GenLibDeps perl script,
or change from compiler to compiler. On Linux, this returns CMake to
a place where it can relably rebuild several targets of LLVM.
I have tried not to change the dependencies from the ones in the current
auto-generated file. The only places I've really diverged are in places
where I was seeing link failures, and added a dependency. The goal of
this patch is not to start changing the dependencies, merely to move
them into the correct location, and an explicit form that we can control
and change when necessary.
This also removes a serialization point in the build because we don't
have to scan all the libraries before we begin building various tools.
We no longer have a step of the build that regenerates a file inside the
source tree. A few other associated cleanups fall out of this.
This isn't really finished yet though. After talking to dgregor he urged
switching to a single CMake macro to construct libraries with both
sources and dependencies in the arguments. Migrating from the two macros
to that style will be a follow-up patch.
Also, llvm-config is still generated with GenLibDeps.pl, which means it
still has slightly buggy dependencies. The internal CMake
'llvm-config-like' macro uses the correct explicitly specified
dependencies however. A future patch will switch llvm-config generation
(when using CMake) to be based on these deps as well.
This may well break Windows. I'm getting a machine set up now to dig
into any failures there. If anyone can chime in with problems they see
or ideas of how to solve them for Windows, much appreciated.
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This can happen in cases where TableGen generated asm matcher cannot check
whether a register operand is in the right register class. e.g. mem operands.
rdar://8204588
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llvm-mc gives an "invalid operand" error for instructions that take an unsigned
immediate which have the high bit set such as:
pblendw $0xc5, %xmm2, %xmm1
llvm-mc treats all x86 immediates as signed values and range checks them.
A small number of x86 instructions use the imm8 field as a set of bits.
This change only changes those instructions and where the high bit is not
ignored. The others remain unchanged.
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The first problem to fix is to stop creating synthetic *Table_gen
targets next to all of the LLVM libraries. These had no real effect as
CMake specifies that add_custom_command(OUTPUT ...) directives (what the
'tablegen(...)' stuff expands to) are implicitly added as dependencies
to all the rules in that CMakeLists.txt.
These synthetic rules started to cause problems as we started more and
more heavily using tablegen files from *subdirectories* of the one where
they were generated. Within those directories, the set of tablegen
outputs was still available and so these synthetic rules added them as
dependencies of those subdirectories. However, they were no longer
properly associated with the custom command to generate them. Most of
the time this "just worked" because something would get to the parent
directory first, and run tablegen there. Once run, the files existed and
the build proceeded happily. However, as more and more subdirectories
have started using this, the probability of this failing to happen has
increased. Recently with the MC refactorings, it became quite common for
me when touching a large enough number of targets.
To add insult to injury, several of the backends *tried* to fix this by
adding explicit dependencies back to the parent directory's tablegen
rules, but those dependencies didn't work as expected -- they weren't
forming a linear chain, they were adding another thread in the race.
This patch removes these synthetic rules completely, and adds a much
simpler function to declare explicitly that a collection of tablegen'ed
files are referenced by other libraries. From that, we can add explicit
dependencies from the smaller libraries (such as every architectures
Desc library) on this and correctly form a linear sequence. All of the
backends are updated to use it, sometimes replacing the existing attempt
at adding a dependency, sometimes adding a previously missing dependency
edge.
Please let me know if this causes any problems, but it fixes a rather
persistent and problematic source of build flakiness on our end.
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Update the debug output interface for MCParsedAsmOperand to have a print()
method which takes an output stream argument, an << operator which invokes
the print method using the given stream, and a dump() method which prints
the operand to the dbgs() stream. This makes the interface more consistent
with the rest of LLVM, and more convenient to use at the debugger command
line.
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and MCSubtargetInfo.
- Added methods to update subtarget features (used when targets automatically
detect subtarget features or switch modes).
- Teach X86Subtarget to update MCSubtargetInfo features bits since the
MCSubtargetInfo layer can be shared with other modules.
- These fixes .code 16 / .code 32 support since mode switch is updated in
MCSubtargetInfo so MC code emitter can do the right thing.
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CPU, and feature string. Parsing some asm directives can change
subtarget state (e.g. .code 16) and it must be reflected in other
modules (e.g. MCCodeEmitter). That is, the MCSubtargetInfo instance
must be shared.
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- Each target asm parser now creates its own MCSubtatgetInfo (if needed).
- Changed AssemblerPredicate to take subtarget features which tablegen uses
to generate asm matcher subtarget feature queries. e.g.
"ModeThumb,FeatureThumb2" is translated to
"(Bits & ModeThumb) != 0 && (Bits & FeatureThumb2) != 0".
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instructions. I choose to handle this with an asmparser hack,
though it could be handled by changing all the instruction definitions
to allow be "setneb" instead of "setne". The asm parser hack is
better in this case, because we want the disassembler to produce
setne, not setneb.
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sahf movl 344(%rdi),%r14d
we used to produce:
t.s:2:1: error: unexpected token in argument list
^
we now produce:
t.s:1:11: error: unexpected token in argument list
sahf movl 344(%rdi),%r14d
^
rdar://8581401
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shift-by-1 instructions, where the asmstring doesn't contain
the implicit 1. It turns out that a bunch of these rotate
instructions were completely broken because they used 1
instead of $1.
This fixes assembly mismatches on "rclb $1, %bl" and friends,
where we used to generate the 3 byte form, we now generate the
proper 2-byte form.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118355 91177308-0d34-0410-b5e6-96231b3b80d8
fixed physical registers. Start moving fp comparison
aliases to the .td file (which default to using %st1 if
nothing is specified).
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floating point stack instructions instead of looking for b/w/l/q.
This fixes issues where we'd accidentally match fistp to fistpl,
when it is in fact an ambiguous instruction.
This changes the behavior of llvm-mc to reject fstp, which was the
correct fix for rdar://8456389:
t.s:1:1: error: ambiguous instructions require an explicit suffix (could be 'fstps', 'fstpl', or 'fstpt')
fstp (%rax)
it also causes us to correctly reject fistp and fist, which addresses
PR8528:
t.s:2:1: error: ambiguous instructions require an explicit suffix (could be 'fistps', or 'fistpl')
fistp (%rax)
^
t.s:3:1: error: ambiguous instructions require an explicit suffix (could be 'fists', or 'fistl')
fist (%rax)
^
Thanks to Ismail Donmez for tracking down the issue here!
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result instruction operand numbering matched the result pattern.
Fixing this allows us to move the xchg/test aliases to the .td file.
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aliases installed and working. They now work when the
matched pattern and the result instruction have exactly
the same operand list.
This is now enough for us to define proper aliases for
movzx and movsx, implementing rdar://8017633 and PR7459.
Note that we do not accept instructions like:
movzx 0(%rsp), %rsi
GAS accepts this instruction, but it doesn't make any
sense because we don't know the size of the memory
operand. It could be 8/16/32 bits.
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directives, allowing things like this:
def : MnemonicAlias<"pop", "popl">, Requires<[In32BitMode]>;
def : MnemonicAlias<"pop", "popq">, Requires<[In64BitMode]>;
Move the rest of the X86 MnemonicAliases over to the .td file.
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sense, when the instruction takes the 16-bit ax register or m16 memory
location. These changes to llvm-mc matches what the darwin assembler
allows for these instructions. Done differently than in r117031 that
caused a valgrind error which was later reverted.
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will accept versions that the darwin assembler allows. Forms ending in "pi" and
forms without all the operands.
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It doesn't look like anything is wrong with the checkin,
but the new test cases expose a mem bug in AsmParser.
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sense, when the instruction takes the 16-bit ax register or m16 memory
location. These changes to llvm-mc matches what the darwin assembler allows
for these instructions. Also added the missing flex (without the wait prefix)
and ud2a as an alias to ud2 (still to add ud2b).
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word forms and suffixed versions to match the darwin assembler in 32-bit and
64-bit modes. This is again for use just with assembly source for llvm-mc .
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be more complete. These are only expected to be used by llvm-mc with assembly
source so there is no pattern, [], in the .td files. Most are being added to
X86InstrInfo.td as Chris suggested and only comments about register uses are
added. Suggestions welcome on the .td changes as I'm not sure on every detail
of the x86 records. More missing instructions will be coming.
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MCStreamer to emit into instead of an MCInst to fill in. This allows the
matcher extra flexibility and is more convenient.
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My previous fix for rdar://8456371 should only apply to fmulp/faddp,
not to fmul/fadd. Instruction set orthogonality is overrated or
something.
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x86-32: 32-bit calls were named "call" not "calll". 64-bit calls were correctly
named "callq", so this only impacted x86-32.
This fixes rdar://8456370 - llvm-mc rejects 'calll'
This also exposes that mingw/64 is generating a 32-bit call instead of a 64-bit call,
I will file a bugzilla.
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-This line, and those below, will be ignored--
M test/MC/AsmParser/X86/x86_instructions.s
M lib/Target/X86/AsmParser/X86AsmParser.cpp
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version because it adds a prefix and makes even less sense
than the other broken forms. This wraps up rdar://8431422
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the end of the line on a parser error, allowing skipping to happen
for syntactic errors but not for semantic errors. Before we would
miss emitting a diagnostic about the second line, because we skipped
it due to the semantic error on the first line:
foo %eax
bar %al
This fixes rdar://8414033 - llvm-mc ignores lines after an invalid instruction mnemonic errors
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always be disambiguated as sldtw. sldtw and sldtq with
a mem operands have the same effect, but sldtw is more
compact. Force it to sldtw, resolving rdar://8017530
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of a mneumonic, report operand errors with better location
info. For example, we now report:
t.s:6:14: error: invalid operand for instruction
cwtl $1
^
but we fail for common cases like:
t.s:11:4: error: invalid operand for instruction
addl $1, $1
^
because we don't know if this is supposed to be the reg/imm or imm/reg
form.
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failed because a subtarget feature was not enabled. Use this to
remove a bunch of hacks from the X86AsmParser for rejecting things
like popfl in 64-bit mode. Previously these hacks weren't needed,
but were important to get a message better than "invalid instruction"
when used in the wrong mode.
This also fixes bugs where pushal would not be rejected correctly in
32-bit mode (just pusha).
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into the middle of the class, and rework how the different sections of
the generated file are conditionally included for simplicity.
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- Currently includes a hack to limit ourselves to "In32BitMode" and "In64BitMode", because we don't have the other infrastructure to properly deal with setting SSE, etc. features on X86.
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- Unfortunate, but necessary for now to handle subtarget instruction matching. Eventually we should factor out the lower level target machine information so we don't need to do this.
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instruction. Added the 64-bit version "jrcxz" so it is recognized and also
added the checks for incorrect uses of "jcxz" in 64-bit mode and "jrcxz" in
32-bit mode. Still to do is to correctly handle the encoding of the
instruction adding the Address-size override prefix byte, 0x67, when the width
of the count register is not the same as the mode the machine is running in.
Which for example means the encoding of "jecxz" depends if you are assembling
as a 32-bit target or a 64-bit target.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105661 91177308-0d34-0410-b5e6-96231b3b80d8
are st(0). These can be encoded using an opcode for storing in st(0) or using
an opcode for storing in st(i), where i can also be 0. To allow testing with
the darwin assembler and get a matching binary the opcode for storing in st(0)
is now used. To do this the same logical trick is use from the darwin assembler
in converting things like this:
fmul %st(0), %st
into this:
fmul %st(0)
by looking for the second operand being X86::ST0 for specific floating point
mnemonics then removing the second X86::ST0 operand. This also has the add
benefit to allow things like:
fmul %st(1), %st
that llvm-mc did not assemble.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104634 91177308-0d34-0410-b5e6-96231b3b80d8
addw $0xFFFF, %ax
should match the same as
addw $-1, %ax
but we used to match it to the longer encoding.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104453 91177308-0d34-0410-b5e6-96231b3b80d8
