expressions for mov instructions instead of silently truncating by default.
For the ARM assembler, we want to avoid misleadingly allowing something
like "mov r0, <symbol>" especially when we turn it into a movw and the
expression <symbol> does not have a :lower16: or :upper16" as part of the
expression. We don't want the behavior of silently truncating, which can be
unexpected and lead to bugs that are difficult to find since this is an easy
mistake to make.
This does change the previous behavior of llvm but actually matches an
older gnu assembler that would not allow this but print less useful errors
of like “invalid constant (0x927c0) after fixup” and “unsupported relocation on
symbol foo”. The error for llvm is "immediate expression for mov requires
:lower16: or :upper16" with correct location information on the operand
as shown in the added test cases.
rdar://12342160
llvm-svn: 206669
alignments on vld/vst instructions. And report errors for
alignments that are not supported.
While this is a large diff and an big test case, the changes
are very straight forward. But pretty much had to touch
all vld/vst instructions changing the addrmode to one of the
new ones that where added will do the proper checking for
the specific instruction.
FYI, re-committing this with a tweak so MemoryOp's default
constructor is trivial and will work with MSVC 2012. Thanks
to Reid Kleckner and Jim Grosbach for help with the tweak.
rdar://11312406
llvm-svn: 205986
It doesn't build with MSVC 2012, because MSVC doesn't allow union
members that have non-trivial default constructors. This change added
'SMLoc AlignmentLoc' to MemoryOp, which made MemoryOp's default ctor
non-trivial.
This reverts commit r205930.
llvm-svn: 205944
alignments on vld/vst instructions. And report errors for
alignments that are not supported.
While this is a large diff and an big test case, the changes
are very straight forward. But pretty much had to touch
all vld/vst instructions changing the addrmode to one of the
new ones that where added will do the proper checking for
the specific instruction.
rdar://11312406
llvm-svn: 205930
This consolidates the duplicated MachO checks in the directive parsing for
various directives that are unsupported for Mach-O. The error message change is
unimportant as this restores the behaviour to that prior to the addition of the
new directive handling. Furthermore, use a more direct check for MachO
targeting rather than an indirect feature check of the assembler.
Also simplify the test execution command to avoid temporary files. Further more,
perform the check in both object and assembly emission.
Whether all non-applicable directives are handled is another question. .fnstart
is marked as being unsupported, however, the complementary .fnend is not. The
additional unwinding directives are also still honoured. This change does not
change that, though, it would be good to validate and mark them as being
unsupported if they are unsupported for the MachO emission.
llvm-svn: 205678
Removed "GNU Assembler extension (compatibility)" definitions from ARMInstrInfo.td
Fixed ARMAsmParser::ParseInstruction GNU compatability branch, so it also works for thumb mode from now.
Added new tests.
llvm-svn: 205622
The trouble as in ARMAsmParser, in ParseInstruction method. It assumes that ARM::R12 + 1 == ARM::SP.
It is wrong, since ARM::<Register> codes are generated by tablegen and actually could be any random numbers.
llvm-svn: 205524
Issue subject: Crash using integrated assembler with immediate arithmetic
Fix description:
Expressions like 'cmp r0, #(l1 - l2) >> 3' could not be evaluated on asm parsing stage,
since it is impossible to resolve labels on this stage. In the end of stage we still have
expression (MCExpr).
Then, when we want to encode it, we expect it to be an immediate, but it still an expression.
Patch introduces a Fixup (MCFixup instance), that is processed after main encoding stage.
llvm-svn: 205094
vector list parameter that is using all lanes "{d0[], d2[]}" but can
match and instruction with a ”{d0, d2}" parameter.
I’m finishing up a fix for proper checking of the unsupported
alignments on vld/vst instructions and ran into this. Thus I don’t
have a test case at this time. And adding all code that will
demonstrate the bug would obscure the very simple one line fix.
So if you would indulge me on not having a test case at this
time I’ll instead offer up a detailed explanation of what is
going on in this commit message.
This instruction:
vld2.8 {d0[], d2[]}, [r4:64]
is not legal as the alignment can only be 16 when the size is 8.
Per this documentation:
A8.8.325 VLD2 (single 2-element structure to all lanes)
<align> The alignment. It can be one of:
16 2-byte alignment, available only if <size> is 8, encoded as a = 1.
32 4-byte alignment, available only if <size> is 16, encoded as a = 1.
64 8-byte alignment, available only if <size> is 32, encoded as a = 1.
omitted Standard alignment, see Unaligned data access on page A3-108.
So when code is added to the llvm integrated assembler to not match
that instruction because of the alignment it then goes on to try to match
other instructions and comes across this:
vld2.8 {d0, d2}, [r4:64]
and and matches it. This is because of the method
ARMOperand::isVecListDPairSpaced() is missing the check of the Kind.
In this case the Kind is k_VectorListAllLanes . While the name of the method
may suggest that this is OK it really should check that the Kind is
k_VectorList.
As the method ARMOperand::isDoubleSpacedVectorAllLanes() is what was
used to match {d0[], d2[]} and correctly checks the Kind:
bool isDoubleSpacedVectorAllLanes() const {
return Kind == k_VectorListAllLanes && VectorList.isDoubleSpaced;
}
where the original ARMOperand::isVecListDPairSpaced() does not check
the Kind:
bool isVecListDPairSpaced() const {
if (isSingleSpacedVectorList()) return false;
return (ARMMCRegisterClasses[ARM::DPairSpcRegClassID]
.contains(VectorList.RegNum));
}
Jim Grosbach has reviewed the change and said: Yep, that sounds right. …
And by "right" I mean, "wow, that's a nasty latent bug I'm really, really
glad to see fixed." :)
rdar://16436683
llvm-svn: 204861
When a label is parsed, check if there is type information available for the
label. If so, check if the symbol is a function. If the symbol is a function
and we are in thumb mode and no explicit thumb_func has been emitted, adjust the
symbol data to indicate that the function definition is a thumb function.
The application of this inferencing is improved value handling in the object
file (the required thumb bit is set on symbols which are thumb functions). It
also helps improve compatibility with binutils.
The one complication that arises from this handling is the MCAsmStreamer. The
default implementation of getOrCreateSymbolData in MCStreamer does not support
tracking the symbol data. In order to support the semantics of thumb functions,
track symbol data in assembly streamer. Although O(n) in number of labels in
the TU, this is already done in various other streamers and as such the memory
overhead is not a practical concern in this scenario.
llvm-svn: 204544
The revision I'm reverting breaks handling of transitive aliases. This blocks us
and breaks sanitizer bootstrap:
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-bootstrap/builds/2651
(and checked locally by Alexey).
This revision is the result of:
svn merge -r204059:204058 -r204028:204027 -r203962:203961 .
+ the regression test added to test/MC/ELF/alias.s
Another way to reproduce the regression with clang:
$ cat q.c
void a1();
void a2() __attribute__((alias("a1")));
void a3() __attribute__((alias("a2")));
void a1() {}
$ ~/work/llvm-build/bin/clang-3.5-good -c q.c && mv q.o good.o && \
~/work/llvm-build/bin/clang-3.5-bad -c q.c && mv q.o bad.o && \
objdump -t good.o bad.o
good.o: file format elf64-x86-64
SYMBOL TABLE:
0000000000000000 l df *ABS* 0000000000000000 q.c
0000000000000000 l d .text 0000000000000000 .text
0000000000000000 l d .data 0000000000000000 .data
0000000000000000 l d .bss 0000000000000000 .bss
0000000000000000 l d .comment 0000000000000000 .comment
0000000000000000 l d .note.GNU-stack 0000000000000000 .note.GNU-stack
0000000000000000 l d .eh_frame 0000000000000000 .eh_frame
0000000000000000 g F .text 0000000000000006 a1
0000000000000000 g F .text 0000000000000006 a2
0000000000000000 g F .text 0000000000000006 a3
bad.o: file format elf64-x86-64
SYMBOL TABLE:
0000000000000000 l df *ABS* 0000000000000000 q.c
0000000000000000 l d .text 0000000000000000 .text
0000000000000000 l d .data 0000000000000000 .data
0000000000000000 l d .bss 0000000000000000 .bss
0000000000000000 l d .comment 0000000000000000 .comment
0000000000000000 l d .note.GNU-stack 0000000000000000 .note.GNU-stack
0000000000000000 l d .eh_frame 0000000000000000 .eh_frame
0000000000000000 g F .text 0000000000000006 a1
0000000000000000 g F .text 0000000000000006 a2
0000000000000000 g .text 0000000000000000 a3
llvm-svn: 204137
Add an assertion that a valid section is referenced. The potential NULL pointer
dereference was identified by the clang static analyzer.
llvm-svn: 204114
This performs the equivalent of a .set directive in that it creates a symbol
which is an alias for another symbol or value which may possibly be yet
undefined. This directive also has the added property in that it marks the
aliased symbol as being a thumb function entry point, in the same way that the
.thumb_func directive does.
The current implementation fails one test due to an unrelated issue. Functions
within .thumb sections are not marked as thumb_func. The result is that
the aliasee function is not valued correctly.
llvm-svn: 204059
.align is handled specially on certain targets. .align without any parameters
on ARM indicates a default alignment (4). Handle the special case in the target
parser, but fall back to the generic parser for the normal version.
llvm-svn: 201988
This adds support for the .short and its alias .hword for adding literal values
into the object file. This is similar to the .word directive, however, rather
than inserting a value of 4 bytes, adds a 2-byte value.
llvm-svn: 201968
ldrd r6, r7 [r2, #15]
simply gives an error and does not triggers an assertion.
As Jim points out, the diagnostic is really strange here,
but fixing that would be more complicated. The missing
comma results in the parser expecting a construct like r2[2],
which is the vector index thing the error message is talking
about. That's not what the user intended, though, and there's
nothing else in the instruction that looks at all like a vector.
Yet more fallout from not having a real parser here and trying
to do context-free generic matching for addressing modes.
rdar://15097243
llvm-svn: 201531
This adds a partial implementation of the .arch_extension directive to the
integrated ARM assembler. There are a number of limitations to this
implementation arising from the target backend support rather than the
implementation itself. Namely, iWMMXT (v1 and v2), Maverick, and XScale support
is not present in the ARM backend. Currently, there is no check for A-class
only (needed for virt), and no ARMv6k detection (needed for os and sec). The
remainder of the extensions are fully supported.
llvm-svn: 201471
This patch fixes the ldr-pseudo implementation to work when used in
inline assembly. The fix is to move arm assembler constant pools
from the ARMAsmParser class to the ARMTargetStreamer class.
Previously we kept the assembler generated constant pools in the
ARMAsmParser object. This does not work for inline assembly because
a new parser object is created for each blob of inline assembly.
This patch moves the constant pools to the ARMTargetStreamer class
so that the constant pool will remain alive for the entire code
generation process.
An ARMTargetStreamer class is now required for the arm backend.
There was no existing implementation for MachO, only Asm and ELF.
Instead of creating an empty MachO subclass, we decided to make the
ARMTargetStreamer a non-abstract class and provide default
(llvm_unreachable) implementations for the non constant-pool related
methods.
Differential Revision: http://llvm-reviews.chandlerc.com/D2638
llvm-svn: 200777
The .object_arch directive indicates an alternative architecture to be specified
in the object file. The directive does *not* effect the enabled feature bits
for the object file generation. This is particularly useful when the code
performs runtime detection and would like to indicate a lower architecture as
the requirements than the actual instructions used.
llvm-svn: 200451
.movsp is an ARM unwinding directive that indicates to the unwinder that a
register contains an offset from the current stack pointer. If the offset is
unspecified, it defaults to zero.
llvm-svn: 200449
This enhances the ARMAsmParser to handle .tlsdescseq directives. This is a
slightly special relocation. We must be able to generate them, but not consume
them in assembly. The relocation is meant to assist the linker in generating a
TLS descriptor sequence. The ELF target streamer is enhanced to append
additional fixups into the current segment and that is used to emit the new
R_ARM_TLS_DESCSEQ relocations.
llvm-svn: 200448
If a complex expression was passed to the .word directive and the first part of
the directive failed to parse, a secondary diagnostic would be produced that
would clutter the error diagnostics. Improve the diagnostics by consuming the
remainder of the statement.
llvm-svn: 200160
Originally, BLX was passed as operand #0 in MachineInstr and as operand
#2 in MCInst. But now, it's operand #2 in both cases.
This patch also removes unnecessary FileCheck in the test case added by r199127.
llvm-svn: 199928
This implements the unwind_raw directive for the ARM IAS. The unwind_raw
directive takes the form of a stack offset value followed by one or more bytes
representing the opcodes to be emitted. The opcode emitted will interpreted as
if it were assembled by the opcode assembler via the standard unwinding
directives.
Thanks to Logan Chien for an extra test!
llvm-svn: 199707
The .personalityindex directive is equivalent to the .personality directive with
the ARM EABI personality with the specific index (0, 1, 2). Both of these
directives indicate personality routines, so enhance the personality directive
handling to take into account personalityindex.
Bonus fix: flush the UnwindContext at the beginning of a new function.
Thanks to Logan Chien for additional tests!
llvm-svn: 199706
This moves the ARM build attributes definitions and support routines into the
Support library. The support routines simply permit the conversion of the value
to and from a string representation.
The movement is prompted in order to permit access to the constants and string
representations from readobj in order to facilitate decoding of the attributes
section.
llvm-svn: 199575
This will allow it to be called from target independent parts of the main
streamer that don't know if there is a registered target streamer or not. This
in turn will allow targets to perform extra actions at specified points in the
interface: add extra flags for some labels, extra work during finalization, etc.
llvm-svn: 199174
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.
llvm-svn: 199068
An improper qualifier would result in a superfluous error due to the parser not
consuming the remainder of the statement. Simply consume the remainder of the
statement to avoid the error.
llvm-svn: 199035
The implicit immediate 0 forms are assembly aliases, not distinct instruction
encodings. Fix the initial implementation introduced in r198914 to an alias to
avoid two separate instruction definitions for the same encoding.
An InstAlias is insufficient in this case as the necessary due to the need to
add a new additional operand for the implicit zero. By using the AsmPsuedoInst,
fall back to the C++ code to transform the instruction to the equivalent
_POST_IMM form, inserting the additional implicit immediate 0.
llvm-svn: 199032
The GNU assembler supports prefixing the expression with a '#' to indiciate that
the value that is being moved is infact a constant. This improves the
compatibility of the integrated assembler's parser for this.
llvm-svn: 198916
The GNU assembler has an extension that allows for the elision of the paired
register (dt2) for the LDRD and STRD mnemonics. Add support for this in the
assembly parser. Canonicalise the usage during the instruction parsing from
the specified version.
llvm-svn: 198915
Operands which involved label arithemetic would previously fail to parse. This
corrects that by adding the additional case for the shift operand validation.
llvm-svn: 198735
This commit adds the pre-UAL aliases of fconsts and fconstd for
vmov.f32 and vmov.f64. They use an InstAlias rather than a
MnemonicAlias to properly support the predicate operand.
We need to support encoded 8-bit constants in order to implement the
pre-UAL fconsts/fconstd aliases for vmov.f32/vmov.f64, so this
commit also fixes parsing of encoded floating point constants used
in vmov.f32/vmov.f64 instructions. Now we can support assembly code
like this:
fconsts s0, #0x70
which is equivalent to vmov.f32 s0, #1.0.
Most of the code was already in place to support this feature.
Previously the code was trying to accept encoded 8-bit float
constants for the vmov.f32/vmov.f64 instructions. It looks like the
support for parsing encoded floats was lost in a refactoring in
commit r148556 and we did not have any tests in place to catch it.
The change in this commit is to keep the parsed value as a 32-bit
float instead of a 64-bit double because that is what the isFPImm()
function expects to find. There is no loss of precision by using a
32-bit float here because we are still limited to an 8-bit encoded
value in the end.
Additionally, we explicitly reject encoded 8-bit floats for
vmovf.32/64. This is the same as the current behavior, but we now do
it explicitly rather than accidently.
llvm-svn: 198697
subsequent changes are easier to review. About to fix some layering
issues, and wanted to separate out the necessary churn.
Also comment and sink the include of "Windows.h" in three .inc files to
match the usage in Memory.inc.
llvm-svn: 198685
Move the unwinding context for the ARM IAS into a helper class. This is purely
a structural refactoring. A follow up change allows for recording additional
depth to improve diagnostics.
llvm-svn: 198664
Parse tag names as well as expressions. The former is part of the
specification, the latter is for improved compatibility with the GNU assembler.
Fix attribute value handling to be comformant to the specification.
llvm-svn: 198662
Introduce a new virtual method Note into the AsmParser. This completements the
existing Warning and Error methods. Use the new method to clean up the output
of the unwind routines in the ARM AsmParser.
llvm-svn: 198661
The ARM backend has been using most of the MachO related subtarget
checks almost interchangeably, and since the only target it's had to
run on has been IOS (which is all three of MachO, Darwin and IOS) it's
worked out OK so far.
But we'd like to support embedded targets under the "*-*-none-macho"
triple, which means everything starts falling apart and inconsistent
behaviours emerge.
This patch should pick a reasonably sensible set of behaviours for the
new triple (and any others that come along, with luck). Some choices
were debatable (notably FP == r7 or r11), but we can revisit those
later when deficiencies become apparent.
llvm-svn: 198617
Checking the trailing letter of the mnemonic is insufficient. Be more thorough
in the scanning of the instruction to ensure that we correctly work with the
predicated mnemonics.
llvm-svn: 198235
The DPR and SPR register lists are also register lists. Furthermore, the
registers need not be checked individually since the register type can be
checked via the list kind. Use that to simplify the logic and fix the incorrect
assertion.
llvm-svn: 198174
Directive parsers must return false if the target assembler is interested in
handling the directive. The Error member function returns true always. Using
the 'return Error()' pattern would incorrectly indicate to the general parser
that the target was not interested in the directive, when in reality it simply
encountered a badly formed directive or some other error. This corrects the
behaviour to ensure that the parser behaves appropriately.
llvm-svn: 198132
We dump any non-empty assembler constant pools after a successful
parse of an assembly file that uses the ldr pseudo opcode. These
per-section constant pools should be output in a deterministic order
to ensure that we always generate the same output when printing the
output with an AsmStreamer.
This patch changes the map data struture used to associate a section
with its constant pool to a MapVector to ensure deterministic
output. Because this map type does not support deletion, we now
check that the constant pool is not empty before dumping its entries
and clear the entries after emitting them with the streamer.
llvm-svn: 197735
This directive will write out the assembler-maintained constant
pool for the current section. These constant pools are created to
support the ldr-pseudo instruction (e.g. ldr r0, =val).
The directive can be used by the programmer to place the constant
pool in a location that can be reached by a pc-relative offset in
the ldr instruction.
llvm-svn: 197711
The ldr-pseudo opcode is a convenience for loading 32-bit constants.
It is converted into a pc-relative load from a constant pool. For
example,
ldr r0, =0x10001
ldr r1, =bar
will generate this output in the final assembly
ldr r0, .Ltmp0
ldr r1, .Ltmp1
...
.Ltmp0: .long 0x10001
.Ltmp1: .long bar
Sketch of the LDR pseudo implementation:
Keep a map from Section => ConstantPool
When parsing ldr r0, =val
parse val as an MCExpr
get ConstantPool for current Section
Label = CreateTempSymbol()
remember val in ConstantPool at next free slot
add operand to ldr that is MCSymbolRef of Label
On finishParse() callback
Write out all non-empty constant pools
for each Entry in ConstantPool
Emit Entry.Label
Emit Entry.Value
Possible improvements to be added in a later patch:
1. Does not convert load of small constants to mov
(e.g. ldr r0, =0x1 => mov r0, 0x1)
2. Does reuse constant pool entries for same constant
The implementation was tested for ARM, Thumb1, and Thumb2 targets on
linux and darwin.
llvm-svn: 197708
This adds support for the .inst directive. This is an ARM specific directive to
indicate an instruction encoded as a constant expression. The major difference
between .word, .short, or .byte and .inst is that the latter will be
disassembled as an instruction since it does not get flagged as data.
llvm-svn: 197657
add_public_tablegen_target adds *CommonTableGen to LLVM_COMMON_DEPENDS.
LLVM_COMMON_DEPENDS affects add_llvm_library (and other add_target stuff) within its scope.
llvm-svn: 195927
The system LDM and STM instructions can't usually writeback to the base
register. The one exception is when an LDM is actually an exception-return
(i.e. contains PC in the register list).
(There's already a test that "ldm sp!, {r0-r3, pc}^" works, which is why there
is no positive test).
rdar://problem/15223374
llvm-svn: 194512
This commit allows the ARM integrated assembler to parse
and assemble the code with .eabi_attribute, .cpu, and
.fpu directives.
To implement the feature, this commit moves the code from
AttrEmitter to ARMTargetStreamers, and several new test
cases related to cortex-m4, cortex-r5, and cortex-a15 are
added.
Besides, this commit also change the Subtarget->isFPOnlySP()
to Subtarget->hasD16() to match the usage of .fpu directive.
This commit changes the test cases:
* Several .eabi_attribute directives in
2010-09-29-mc-asm-header-test.ll are removed because the .fpu
directive already cover the functionality.
* In the Cortex-A15 test case, the value for
Tag_Advanced_SIMD_arch has be changed from 1 to 2,
which is more precise.
llvm-svn: 193524
When assembling, a .thumb_func directive is supposed to be applicable to the
next symbol definition, even if there are intervening directives. We were
racing ahead to try and find it, and this commit should fix the issue.
Patch by Gabor Ballabas
llvm-svn: 193403
POP instructions are aliased to the ARM LDM variants but have different syntax.
This caused two problems: we tried to access a non-existent operand to annotate
the '!', and the error message didn't make much sense.
With some vigorous hand-waving in the error message both problems can be
fixed.
llvm-svn: 193322
The set of circumstances where the writeback register is allowed to be in the
list of registers is rather baroque, but I think this implements them all on
the assembly parsing side.
For disassembly, we still warn about an ARM-mode LDM even if the architecture
revision is < v7 (the required architecture information isn't available). It's
a silly instruction anyway, so hopefully no-one will mind.
rdar://problem/15223374
llvm-svn: 193185
This patch fixes an old FIXME by creating a MCTargetStreamer interface
and moving the target specific functions for ARM, Mips and PPC to it.
The ARM streamer is still declared in a common place because it is
used from lib/CodeGen/ARMException.cpp, but the Mips and PPC are
completely hidden in the corresponding Target directories.
I will send an email to llvmdev with instructions on how to use this.
llvm-svn: 192181
The hint instructions ("nop", "yield", etc) are mostly Thumb2-only, but have
been ported across to the v6M architecture. Fortunately, v6M seems to sit
nicely between v6 (thumb-1 only) and v6T2, so we can add a feature for it
fairly easily.
rdar://problem/15144406
llvm-svn: 192097
When MC was first added, targets could use hasRawTextSupport to keep features
working before they were added to the MC interface.
The design goal of MC is to provide an uniform api for printing assembly and
object files. Short of relaxations and other corner cases, a object file is
just another representation of the assembly.
It was never the intention that targets would keep doing things like
if (hasRawTextSupport())
Set flags in one way.
else
Set flags in another way.
When they do that they create two code paths and the object file is no longer
just another representation of the assembly. This also then requires testing
with llc -filetype=obj, which is extremelly brittle.
This patch removes some of these hacks by replacing them with smaller ones.
The ARM flag setting is trivial, so I just moved it to the constructor. For
Mips, the patch adds two temporary hack directives that allow the assembly
to represent the same things as the object file was already able to.
The hope is that the mips developers will replace the hack directives with
the same ones that gas uses and drop the -print-hack-directives flag.
I will also try to implement a target streamer interface, so that we can
move this out of the common code.
In summary, for any new work, two rules of the thumb are
* Don't use "llc -filetype=obj" in tests.
* Don't add calls to hasRawTextSupport.
llvm-svn: 192035
As specified in A8.8.72/A8.8.73/A8.8.74 in the ARM ARM, all variants of the ARM LDRD instruction have the following two constraints:
LDRD<c> <Rt>, <Rt2>, ...
(a) Rt must be even-numbered and not r14
(b) Rt2 must be R(t+1)
If those two constraints are not met the result of executing the instruction will be unpredictable.
Constraint (b) was already enforced, this commit adds support for constraint (a).
Fixes rdar://14479793.
llvm-svn: 191520
LDRD<c> <Rt>, <Rt2>, <label>
LDRD<c> <Rt>, <Rt2>, [<Rn>{, #+/-<imm>}]
LDRD<c> <Rt>, <Rt2>, [<Rn>], #+/-<imm>
LDRD<c> <Rt>, <Rt2>, [<Rn>, #+/-<imm>]!
As specified in A8.8.72/A8.8.73 in the ARM ARM, the T1 encoding has a constraint which enforces that Rt != Rt2.
If this constraint is not met the result of executing the instruction will be unpredictable.
Fixes rdar://14479780.
llvm-svn: 191504
The 'Deprecated' class allows you to specify a SubtargetFeature that the
instruction is deprecated on.
The 'ComplexDeprecationPredicate' class allows you to define a custom
predicate that is called to check for deprecation.
For example:
ComplexDeprecationPredicate<"MCR">
would mean you would have to define the following function:
bool getMCRDeprecationInfo(MCInst &MI, MCSubtargetInfo &STI,
std::string &Info)
Which returns 'false' for not deprecated, and 'true' for deprecated
and store the warning message in 'Info'.
The MCTargetAsmParser constructor was chaned to take an extra argument of
the MCInstrInfo class, so out-of-tree targets will need to be changed.
llvm-svn: 190598
These were pretty straightforward instructions, with some assembly support
required for HLT.
The ARM assembler is keen to split the instruction mnemonic into a
(non-existent) 'H' instruction with the LT condition code. An exception for
HLT is needed.
HLT follows the same rules as BKPT when in IT blocks, so the special BKPT
hadling code has been adapted to handle HLT also.
Regression tests added including diagnostic tests for out of range immediates
and illegal condition codes, as well as negative tests for pre-ARMv8.
llvm-svn: 190053
According to the ARM specification, "mov" is a valid mnemonic for all Thumb2 MOV encodings.
To achieve this, the patch adds one instruction alias with a special range condition to avoid collision with the Thumb1 MOV.
llvm-svn: 188901
Thumb2 literal loads use an offset encoding which allows for
negative zero. This fixes parsing and encoding so that #-0
is correctly processed. The parser represents #-0 as INT32_MIN.
llvm-svn: 188549
There are many Thumb instructions which take 12-bit immediates encoded in a special
8-byte value + 4-byte rotator form. Not all numbers are represented, and it's legal
to transform an assembly instruction to be able to encode the immediate.
For example: AND and BIC are complementary instructions; one can switch the AND
to a BIC as long as the immediate is complemented.
The intent is to switch one instruction into its complementary one when the immediate
cannot be encoded in the form requested in the original assembly and when the
complementary immediate is encodable.
The patch addresses two issues:
1. definition of t2SOImmNot immediate - it has to check that the orignal value is
not encoded naturally
2. t2AND and t2BIC instruction aliases which should use the Thumb2 SOImm operand
rather than the ARM one.
llvm-svn: 188548
1. The offset range for Thumb1 PC relative loads is [0..1020] and not [-1024..1020]
2. Thumb2 PC relative loads may define the PC, so the restriction placed on target register is removed
3. Removes unneeded alias between "ldr.n" and t1LDRpci. ".n" is actually stripped by both tablegen
and the ASM parser, so this alias rule really does nothing
llvm-svn: 188466
The long encoding for Thumb2 unconditional branches is broken.
Additionally, there is no range checking for target operands; as such
for instructions originating in assembly code, only short Thumb encodings
are generated, regardless of the bitsize needed for the offset.
Adding range checking is non trivial due to the representation of Thumb
branch instructions. There is no true difference between conditional and
unconditional branches in terms of operands and syntax - even unconditional
branches have a predicate which is expected to match that of the IT block
they are in. Yet, the encodings and the permitted size of the offset differ.
Due to this, for any mnemonic there are really 4 encodings to choose for.
The problem cannot be handled in the parser alone or by manipulating td files.
Because the parser builds first a set of match candidates and then checks them
one by one, whatever tablegen-only solution might be found will ultimately be
dependent of the parser's evaluation order. What's worse is that due to the fact
that all branches have the same syntax and the same kinds of operands, that
order is governed by the lexicographical ordering of the names of operand
classes...
To circumvent all this, any necessary disambiguation is added to the instruction
validation pass.
llvm-svn: 188067
While the .td entry is nice and all, it takes a pretty gross hack in
ARMAsmParser::ParseInstruction() because of handling of other "subs"
instructions to get it to match. Ran it by Jim Grosbach and he said it was
about what he expected to make this work given the existing code.
rdar://14214063
llvm-svn: 187530
instructions. With this patch:
1. ldr.n is recognized as mnemonic for the short encoding
2. ldr.w is recognized as menmonic for the long encoding
3. ldr will map to either short or long encodings depending on the size of the offset
llvm-svn: 186831
After Ulrich's r180677 (thanks!) TableGen is intelligent enough to
handle tied constraints involving complex operands properly, so
virtually all of the ARM custom converters are now unnecessary.
llvm-svn: 186810
This adds a new decoder table/namespace 'VFPV8', as these instructions have their
top 4 bits as 0b1111, while other Thumb instructions have 0b1110.
llvm-svn: 185642
Before the fix Thumb2 instructions of type "add rD, rN, #imm" (T3 encoding, see ARM ARM A8.8.4) with rD and rN both being low registers (r0-r7) were classified as having the T4 encoding.
The T4 encoding doesn't have a cc_out operand so for above instructions the operand gets erroneously removed, corrupting the token stream and leading to parse errors later in the process.
This bug prevented "add r1, r7, #0xcbcbcbcb" from being assembled correctly.
Fixes <rdar://problem/14224440>.
llvm-svn: 185575
1. it should accept only 4-byte aligned addresses
2. the maximum offset should be 1020
3. it should be encoded with the offset scaled by two bits
llvm-svn: 185528
Unfortunately this addresses two issues (by the time I'd disentangled the logic
it wasn't worth putting it back to half-broken):
+ Coprocessor instructions should all be predicable in Thumb mode.
+ BKPT should never be predicable.
llvm-svn: 184965
"When assembling to the ARM instruction set, the .N qualifier produces
an assembler error and the .W qualifier has no effect."
In the pre-matcher handler in the asm parser the ".w" (wide) qualifier
when in ARM mode is now discarded. And an error message is now
produced when the ".n" (narrow) qualifier is used in ARM mode.
Test cases for these were added.
rdar://14064574
llvm-svn: 184224
When using a positive offset, literal loads where encoded
as if it was negative, because:
- The sign bit was not assigned to an operand
- The addrmode_imm12 operand was not encoding the sign bit correctly
This patch also makes the assembler look at the .w/.n specifier for
loads.
llvm-svn: 184182
Negative zero is returned by the primary expression parser as INT32_MIN, so all that the method needs to do is to accept this value.
Behavior already present for Thumb2.
llvm-svn: 183734
Some ARM CPUs only support ARM mode (ancient v4 ones, for example) and some
only support Thumb mode (M-class ones currently). This makes sure such CPUs
default to the correct mode and makes the AsmParser diagnose an attempt to
switch modes incorrectly.
rdar://14024354
llvm-svn: 183710
This commit implements the AsmParser for fnstart, fnend,
cantunwind, personality, handlerdata, pad, setfp, save, and
vsave directives.
This commit fixes some minor issue in the ARMELFStreamer:
* The switch back to corresponding section after the .fnend
directive.
* Emit the unwind opcode while processing .fnend directive
if there is no .handlerdata directive.
* Emit the unwind opcode to .ARM.extab while processing
.handlerdata even if .personality directive does not exist.
llvm-svn: 181603
"hint" space for Thumb actually overlaps the encoding space of the CPS
instruction. In actuality, hints can be defined as CPS instructions where imod
and M bits are all nil.
Handle decoding of permitted nop-compatible hints (i.e. nop, yield, wfi, wfe,
sev) in DecodeT2CPSInstruction.
This commit adds a proper diagnostic message for Imm0_4 and updates all tests.
Patch by Mihail Popa <Mihail.Popa@arm.com>.
llvm-svn: 180617
variant/dialect. Addresses a FIXME in the emitMnemonicAliases function.
Use and test case to come shortly.
rdar://13688439 and part of PR13340.
llvm-svn: 179804
The reference manual defines only 5 permitted values for the immediate field of the "hint" instruction:
1. nop (imm == 0)
2. yield (imm == 1)
3. wfe (imm == 2)
4. wfi (imm == 3)
5. sev (imm == 4)
Therefore, restrict the permitted values for the "hint" instruction to 0 through 4.
Patch by Mihail Popa <Mihail.Popa@arm.com>
llvm-svn: 179707
The parser will now accept instructions with alignment specifiers written like
vld1.8 {d16}, [r0:64]
, while also still accepting the incorrect syntax
vld1.8 {d16}, [r0, :64]
llvm-svn: 175164
Use the validateTargetOperandClass() hook to match literal '#0' operands in
InstAlias definitions. Previously this required per-instruction C++ munging of the
operand list, but not is handled as a natural part of the matcher. Much better.
No additional tests are required, as the pre-existing tests for these instructions
exercise the new behaviour as being functionally equivalent to the old.
llvm-svn: 174488
infrastructure on MCStreamer to test for whether there is an
MCELFStreamer object available.
This is just a cleanup on the AsmPrinter side of things, moving ad-hoc
tests of random APIs to a direct type query. But the AsmParser
completely broken. There were no tests, it just blindly cast its
streamer to an MCELFStreamer and started manipulating it.
I don't have a test case -- this actually failed on LLVM's own
regression test suite. Unfortunately the failure only appears when the
stars, compilers, and runtime align to misbehave when we read a pointer
to a formatted_raw_ostream as-if it were an MCAssembler. =/
UBSan would catch this immediately.
Many thanks to Matt for doing about 80% of the debugging work here in
GDB, Jim for helping to explain how exactly to fix this, and others for
putting up with the hair pulling that ensued during debugging it.
llvm-svn: 174118
