In Intel syntax, it's not uncommon to see a "short" modifier on Jcc conditional
jumps, which indicates the offset should be a "short jump" (8-bit immediate
offset from EIP, -128 to +127). This patch expands to all recognized Jcc
condition codes, and removes the inline restriction.
Clang already ignores "jmp short" in inline assembly. However, only "jmp" and a
couple of Jcc are actually checked, and only inline (i.e., not when using the
integrated assembler for asm sources). A quick search through asm-containing
libraries at hand shows a pretty broad range of Jcc conditions spelled with
"short."
GAS ignores the "short" modifier, and instead uses an encoding based on the
given immediate. MS inline seems to do the same, and I suspect MASM does, too.
NASM will yield an error if presented with an out-of-range immediate value.
Example of GCC 9.1 and MSVC v19.20, "jmp short" with offsets that do and do not
fit within 8 bits: https://gcc.godbolt.org/z/aFZmjY
Differential Revision: https://reviews.llvm.org/D61990
llvm-svn: 360954
All of these instructions consume one encoded register and the other register is %st. They either write the result to %st or the encoded register. Previously we printed both arguments when the encoded register was written. And we printed one argument when the result was written to %st. For the stack popping forms the encoded register is always the destination and we didn't print both operands. This was inconsistent with gcc and objdump and just makes the output assembly code harder to read.
This patch changes things to always print both operands making us consistent with gcc and objdump. The parser should still be able to handle the single register forms just as it did before. This also matches the GNU assembler behavior.
llvm-svn: 353061
Looking into gcc and objdump behavior more this was overly aggressive. If the register is encoded in the instruction we should print %st(0), if its implicit we should print %st.
I'll be making a more directed change in a future patch.
llvm-svn: 353013
Summary:
When calculating clobbers for MS style inline assembly we fail if the asm clobbers stack top because we print st(0) and try to pass it through the gcc register name check. This was found with when I attempted to make a emms/femms clobber all ST registers. If you use emms/femms in MS inline asm we would try to use st(0) as the clobber name but clang would think that wasn't a valid clobber name.
This also matches what objdump disassembly prints. It's also what is printed by gcc -S.
Reviewers: RKSimon, rnk, efriedma, spatel, andreadb, lebedev.ri
Reviewed By: rnk
Subscribers: eraman, gbedwell, lebedev.ri, llvm-commits
Differential Revision: https://reviews.llvm.org/D57621
llvm-svn: 352985
By default, the second register gets assigned to the index register slot. But ESP can't be an index register so we need to swap it with the other register.
There's still a slight bug that we allow [EAX+ESP*1]. The existence of the multiply even though its with 1 should force ESP to the index register and trigger an error, but it doesn't currently.
llvm-svn: 335394
The second register is the index register and should only be %si or %di if used with a base register. And in that case the base register should be %bp or %bx.
This makes us compatible with gas.
We do still need to support both orders with Intel syntax which uses [bp+si] and [si+bp]
llvm-svn: 335384
Previously for instructions like fxsave we would print "opaque ptr" as part of the memory operand. Now we print nothing.
We also no longer accept "opaque ptr" in the parser. We still accept any size to be specified for these instructions, but we may want to consider only parsing when no explicit size is specified. This what gas does.
llvm-svn: 331243
Summary:
Intel documentation shows the memory operand as the first operand. But we currently treat it as the second operand. Conceptually the order doesn't matter since it doesn't write memory. We have aliases to parse with the operands in either order and the isel matching is commutable.
For the register®ister form order does matter for the assembly parser. PR22995 was previously filed and fixed by changing the register®ister form from MRMSrcReg to MRMDestReg to match gas. Ideally the memory form should match by using MRMDestMem.
I believe this supercedes D38025 which was trying to switch the register®ister form back to pre-PR22995.
Reviewers: aymanmus, RKSimon, zvi
Reviewed By: aymanmus
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D38120
llvm-svn: 314639
MS allows the following size directives: float/double and long as synonymous to dword/qword and dword, respectively.
Differential Revision: https://reviews.llvm.org/D37190
llvm-svn: 314410
Some refactoring to X86AsmParser, mostly regarding the way rewrites are conducted.
Mainly, we try to concentrate all the rewrite effort under one hood, so it'll hopefully be less of a mess and easier to maintain and understand.
naturally, some frontend tests were affected: D36794
Differential Revision: https://reviews.llvm.org/D36793
llvm-svn: 311639
Currently, far jmp/call which utilizes a 48bit memory operand would have been invoked via the 'lcall/ljmp' mnemonic (intel style).
This patch align those variants to formal intel spec
Differential Revision: https://reviews.llvm.org/D35846
llvm-svn: 310485
Enable the next form (intel style):
"mov <reg64>, <largeImm>"
which is should be available,
where <largeImm> stands for immediates which exceed the range of a singed 32bit integer
Differential Revision: https://reviews.llvm.org/D28988
llvm-svn: 293030
There's an overloading of the "movsd" and "cmpsd" instructions, e.g. movsd can be either "Move Data from String to String" or "Move or Merge Scalar Double-Precision Floating-Point Value".
The former should produce warnings when parsing a memory operand that is not ESI/EDI, but the latter should not.
Fixed the code to produce warnings only after making sure we're dealing with the first case.
Expanded the tests of the produced warnings + fixed RUN line of the test so that it would check both stdout and stderr
Differential Revision: http://reviews.llvm.org/D16359
llvm-svn: 258393
According to x86 spec "xlat m8" is a legal instruction and it is equivalent to "xlatb".
Differential Revision: http://reviews.llvm.org/D15150
llvm-svn: 258135
The following are legal according to X86 spec:
ins mem, DX
outs DX, mem
lods mem
stos mem
scas mem
cmps mem, mem
movs mem, mem
Differential Revision: http://reviews.llvm.org/D14827
llvm-svn: 258132
According to x86 spec, loopz and loopnz should be supported for Intel syntax, where loopz is equivalent to loope and loopnz is equivalent to loopne.
Differential Revision: http://reviews.llvm.org/D15148
llvm-svn: 254877
LLVM Missing the following instructions: fadd\fdiv\fmul\fsub\fsubr\fdivr.
GAS and MS supporting this instruction and lowering them in to a faddp\fdivp\fmulp\fsubp\fsubrp\fdivrp instructions.
Differential Revision: http://reviews.llvm.org/D14217
llvm-svn: 252908
COMISD should receive QWORD because it is defined as
(V)COMISD xmm1, xmm2/m64
COMISS should receive DWORD because it is defined as
(V)COMISS xmm1, xmm2/m32
Differential Revision: http://reviews.llvm.org/D11712
llvm-svn: 245551
REPE, REPZ, REPNZ, REPNE should have mnemonics for Intel syntax as well.
Currently using these instructions causes compilation errors for Intel syntax.
Differential Revision: http://reviews.llvm.org/D11794
llvm-svn: 244584
The "imul reg, imm" alias is not defined for intel syntax.
In intel syntax there is no w/l/q suffix for the imul instruction.
Differential Revision: http://reviews.llvm.org/D11887
llvm-svn: 244582
Fixes PR23455, where, when TableGen generates the matcher from the
AsmString, it splits "cmp${cc}ss" into tokens, and the "ss" suffix
is recognized as the SS register.
I can't think of a situation where that's a feature, not a bug, hence:
when a token is "isolated", i.e., it is followed and preceded by
separators, it shouldn't be parsed as a register.
Differential Revision: http://reviews.llvm.org/D9844
llvm-svn: 238536
Nico Rieck added support for this 32-bit COFF relocation some time ago
for Win64 stuff. It appears that as an oversight, the assembly output
used "foo"@IMGREL32 instead of "foo"@IMGREL, which is what we can parse.
Sadly, there were actually tests that took in IMGREL and put out
IMGREL32, and we didn't notice the inconsistency. Oh well. Now LLVM can
assemble it's own output with slightly more fidelity.
llvm-svn: 218437
Instructions like 'fxsave' and control flow instructions like 'jne'
match any operand size. The loop I added to the Intel syntax matcher
assumed that using a different size would give a different instruction.
Now it handles the case where we get the same instruction for different
memory operand sizes.
This also allows us to remove the hack we had for unsized absolute
memory operands, because we can successfully match things like 'jnz'
without reporting ambiguity. Removing this hack uncovered test case
involving 'fadd' that was ambiguous. The memory operand could have been
single or double precision.
llvm-svn: 216604
The existing matcher has lots of AT&T assembly dialect assumptions baked
into it. In particular, the hack for resolving the size of a memory
operand by appending the four most common suffixes doesn't work at all.
The Intel assembly dialect mnemonic table has ambiguous entries, so we
need to try matching multiple times with different operand sizes, since
that's the only way to choose different instruction variants.
This makes us more compatible with gas's implementation of Intel
assembly syntax. MSVC assumes you want byte-sized operations for the
instructions that we reject as ambiguous.
Reviewed By: grosbach
Differential Revision: http://reviews.llvm.org/D4747
llvm-svn: 216481
We would get confused by '@' characters in symbol names, we would
mistake the text following them for the variant kind.
When an identifier a string, the variant kind will never show up inside
of it. Instead, check to see if there is a variant following the
string.
This fixes PR19965.
llvm-svn: 211249
David L. Jones