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
This adds an instruction alias to make the assembler recognize the alternate literal form: pli [PC, #+/-<imm>]
See A8.8.129 in the ARM ARM (DDI 0406C.b).
Fixes <rdar://problem/14403733>.
llvm-svn: 186459
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
According to ARM EHABI section 9.2, if the
__aeabi_unwind_cpp_pr1() or __aeabi_unwind_cpp_pr2() is
used, then the handler data must be emitted after the unwind
opcodes. The handler data consists of several words, and
should be terminated by zero.
In case that the .handlerdata directive is not specified by
the programmer, we should emit zero to terminate the handler
data.
llvm-svn: 185422
The mapping between SRS pseudo-instructions and SRS native instructions was incorrect, the correct mapping is:
srsfa -> srsib
srsea -> srsia
srsfd -> srsdb
srsed -> srsda
This fixes <rdar://problem/14214734>.
llvm-svn: 185155
algorithm when assigning EnumValues to the synthesized registers.
The current algorithm, LessRecord, uses the StringRef compare_numeric
function. This function compares strings, while handling embedded numbers.
For example, the R600 backend registers are sorted as follows:
T1
T1_W
T1_X
T1_XYZW
T1_Y
T1_Z
T2
T2_W
T2_X
T2_XYZW
T2_Y
T2_Z
In this example, the 'scaling factor' is dEnum/dN = 6 because T0, T1, T2
have an EnumValue offset of 6 from one another. However, in other parts
of the register bank, the scaling factors are different:
dEnum/dN = 5:
KC0_128_W
KC0_128_X
KC0_128_XYZW
KC0_128_Y
KC0_128_Z
KC0_129_W
KC0_129_X
KC0_129_XYZW
KC0_129_Y
KC0_129_Z
The diff lists do not work correctly because different kinds of registers have
different 'scaling factors'. This new algorithm, LessRecordRegister, tries to
enforce a scaling factor of 1. For example, the registers are now sorted as
follows:
T1
T2
T3
...
T0_W
T1_W
T2_W
...
T0_X
T1_X
T2_X
...
KC0_128_W
KC0_129_W
KC0_130_W
...
For the Mips and R600 I see a 19% and 6% reduction in size, respectively. I
did see a few small regressions, but the differences were on the order of a
few bytes (e.g., AArch64 was 16 bytes). I suspect there will be even
greater wins for targets with larger register files.
Patch reviewed by Jakob.
rdar://14006013
llvm-svn: 185094
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
The cdp2 instruction should have the same restrictions as cdp on the
co-processor registers.
VFP instructions on v8/AArch32 share the same encoding space as cdp2.
llvm-svn: 184445
"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
- Don't use assert(0), or tests may pass or fail according to assertions.
- For now, The tests are marked as XFAIL for win32 hosts.
FIXME: Could we avoid XFAIL to specify triple in the RUN lines?
llvm-svn: 183728
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
Changes to ARM unwind opcode assembler:
* Fix multiple .save or .vsave directives. Besides, the
order is preserved now.
* For the directives which will generate multiple opcodes,
such as ".save {r0-r11}", the order of the unwind opcode
is fixed now, i.e. the registers with less encoding value
are popped first.
* Fix the $sp offset calculation. Now, we can use the
.setfp, .pad, .save, and .vsave directives at any order.
Changes to test cases:
* Add test cases to check the order of multiple opcodes
for the .save directive.
* Fix the incorrect $sp offset in the test case. The
stack pointer offset specified in the test case was
incorrect. (Changed test cases: ehabi-mc-section.ll and
ehabi-mc.ll)
* The opcode to restore $sp are slightly reordered. The
behavior are not changed, and the new output is same
as the output of GNU as. (Changed test cases:
eh-directive-pad.s and eh-directive-setfp.s)
llvm-svn: 183627
These instructions are deprecated oddities, but we still need to be able to
disassemble (and reassemble) them if and when they're encountered.
Patch by Amaury de la Vieuville.
llvm-svn: 183011
For COFF and MachO, sections semantically have relocations that apply to them.
That is not the case on ELF.
In relocatable objects (.o), a section with relocations in ELF has offsets to
another section where the relocations should be applied.
In dynamic objects and executables, relocations don't have an offset, they have
a virtual address. The section sh_info may or may not point to another section,
but that is not actually used for resolving the relocations.
This patch exposes that in the ObjectFile API. It has the following advantages:
* Most (all?) clients can handle this more efficiently. They will normally walk
all relocations, so doing an effort to iterate in a particular order doesn't
save time.
* llvm-readobj now prints relocations in the same way the native readelf does.
* probably most important, relocations that don't point to any section are now
visible. This is the case of relocations in the rela.dyn section. See the
updated relocation-executable.test for example.
llvm-svn: 182908
ARM FastISel is currently only enabled for iOS non-Thumb1, and I'm working on
enabling it for other targets. As a first step I've fixed some of the tests.
Changes to ARM FastISel tests:
- Different triples don't generate the same relocations (especially
movw/movt versus constant pool loads). Use a regex to allow either.
- Mangling is different. Use a regex to allow either.
- The reserved registers are sometimes different, so registers get
allocated in a different order. Capture the names only where this
occurs.
- Add -verify-machineinstrs to some tests where it works. It doesn't
work everywhere it should yet.
- Add -fast-isel-abort to many tests that didn't have it before.
- Split out the VarArg test from fast-isel-call.ll into its own
test. This simplifies test setup because of --check-prefix.
Patch by JF Bastien
llvm-svn: 181801
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
The reference encoding is correct, but written in the wrong byte order (these are Thumb tests, while the reference is in ARM byte order).
llvm-svn: 181420
"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
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
According to the ARM reference manual, constant offsets are mandatory for pre-indexed addressing modes.
The MC disassembler was not obeying this when the offset is 0.
It was producing instructions like: str r0, [r1]!.
Correct syntax is: str r0, [r1, #0]!.
This change modifies the dumping of operands so that the offset is always printed, regardless of its value, when pre-indexed addressing mode is used.
Patch by Mihail Popa <Mihail.Popa@arm.com>
llvm-svn: 179398
These instructions aren't universally available, but depend on a specific
extension to the normal ARM architecture (rather than, say, v6/v7/...) so a new
feature is appropriate.
This also enables the feature by default on A-class cores which usually have
these extensions, to avoid breaking existing code and act as a sensible
default.
llvm-svn: 179171
This fixes an issue where trying to assemlbe valid ADR instructions would cause
LLVM to hit a failed assertion.
Patch by Keith Walker.
llvm-svn: 176189
With bundle alignment, instructions all get their own MCFragments
(unless they are in a bundle-locked group). For instructions with
fixups, this is an MCDataFragment. Emitting actual data (e.g. for
.long) attempts to re-use MCDataFragments, which we don't want int
this case since it leads to fragments which exceed the bundle size.
So, don't reuse them in this case.
Also adds a test and fixes some formatting.
llvm-svn: 175316
assembler should also accept a two arg form, as the docuemntation specifies that
the first (destination) register is optional.
This patch uses TwoOperandAliasConstraint to add the two argument form.
It also fixes an 80-column formatting problem in:
test/MC/ARM/neon-bitwise-encoding
<rdar://problem/12909419> Clang rejects ARM NEON assembly instructions
llvm-svn: 175221
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
and update ELF header e_flags.
Currently gathering information such as symbol,
section and data is done by collecting it in an
MCAssembler object. From MCAssembler and MCAsmLayout
objects ELFObjectWriter::WriteObject() forms and
streams out the ELF object file.
This patch just adds a few members to the MCAssember
class to store and access the e_flag settings. It
allows for runtime additions to the e_flag by
assembler directives. The standalone assembler can
get to MCAssembler from getParser().getStreamer().getAssembler().
This patch is the generic infrastructure and will be
followed by patches for ARM and Mips for their target
specific use.
Contributer: Jack Carter
llvm-svn: 173882
make into the last commit.
Also, update the test-generation script to generate an exhaustive test for
align_to_end as well, and include the generated test.
llvm-svn: 171811
immediate generates the narrow version. Needed when doing round-trip
assemble/disassemble testing using the alternate syntax that specifies
'pc' directly.
llvm-svn: 170255
Before this patch, when you objdump an LLVM-compiled file, objdump tried to
decode data-in-code sections as if they were code. This patch adds the missing
Mapping Symbols, as defined by "ELF for the ARM Architecture" (ARM IHI 0044D).
Patch based on work by Greg Fitzgerald.
llvm-svn: 169609
When the operand is a plain immediate rather than a label, print it
as [pc, #imm] like we do for the Thumb2 wide encoding variant.
rdar://12154503
llvm-svn: 166991
is 24 bits not 20 and the decoding needed to correctly handle converting the
J1 and J2 bits to their I1 and I2 values to reconstruct the displacement.
llvm-svn: 166982
This patch fixes load/store instructions to handle less common cases
like "asr #32", "rrx" properly throughout the MC layer.
Patch by Chris Lidbury.
llvm-svn: 164455
As an example of how the custom DiagnosticType can be used to provide
better operand-mismatch diagnostics, add a custom diagnostic for
the imm0_15 operand class used for several system instructions.
Update the tests to expect the improved diagnostic.
rdar://8987109
llvm-svn: 159051
The NOP, WFE, WFI, SEV and YIELD instructions are all hints w/
a different immediate value in bits [7,0]. Define a generic HINT
instruction and refactor NOP, WFI, WFI, SEV and YIELD to be
assembly aliases of that.
rdar://11600518
llvm-svn: 158674
Use a dedicated MachO load command to annotate data-in-code regions.
This is the same format the linker produces for final executable images,
allowing consistency of representation and use of introspection tools
for both object and executable files.
Data-in-code regions are annotated via ".data_region"/".end_data_region"
directive pairs, with an optional region type.
data_region_directive := ".data_region" { region_type }
region_type := "jt8" | "jt16" | "jt32" | "jta32"
end_data_region_directive := ".end_data_region"
The previous handling of ARM-style "$d.*" labels was broken and has
been removed. Specifically, it didn't handle ARM vs. Thumb mode when
marking the end of the section.
rdar://11459456
llvm-svn: 157062
the 0b10 mask encoding bits. Make MSR APSR writes without a _<bits> qualifier
an alias for MSR APSR_nzcvq even though ARM as deprecated it use. Also add
support for suffixes (_nzcvq, _g, _nzcvqg) for APSR versions. Some FIXMEs in
the code for better error checking when versions shouldn't be used.
rdar://11457025
llvm-svn: 157019
for the assembler and disassembler. Which were not being set/read correctly
for offsets greater than 22 bits in some cases.
Changes to lib/Target/ARM/ARMAsmBackend.cpp from Gideon Myles!
llvm-svn: 156118
Expressions for movw/movt don't always have an :upper16: or :lower16:
on them and that's ok. When they don't, it's just a plain [0-65536]
immediate result, effectively the same as a :lower16: variant kind.
rdar://10550147
llvm-svn: 155941
Make sure when parsing the Thumb1 sp+register ADD instruction that
the source and destination operands match. In thumb2, just use the
wide encoding if they don't. In Thumb1, issue a diagnostic.
rdar://11219154
llvm-svn: 155748
When an instruction match is found, but the subtarget features it
requires are not available (missing floating point unit, or thumb vs arm
mode, for example), issue a diagnostic that identifies what the feature
mismatch is.
rdar://11257547
llvm-svn: 155499
Use the new TwoOperandAliasConstraint to handle lots of the two-operand aliases
for NEON instructions. There's still more to go, but this is a good chunk of
them.
llvm-svn: 155210
While there is an encoding for it in VUZP, the result of that is undefined,
so we should avoid it. Define the instruction as a pseudo for VTRN.32
instead, as the ARM ARM indicates.
rdar://11222366
llvm-svn: 154511
While there is an encoding for it in VZIP, the result of that is undefined,
so we should avoid it. Define the instruction as a pseudo for VTRN.32
instead, as the ARM ARM indicates.
rdar://11221911
llvm-svn: 154505
predicates.
Also remove NEON2 since it's not really useful and it is confusing. If
NEON + VFP4 implies NEON2 but NEON2 doesn't imply NEON + VFP4, what does it
really mean?
rdar://10139676
llvm-svn: 154480
1. The new instruction itinerary entries are not properly described.
2. The asm parser can't handle vfms and vfnms.
3. There were no assembler, disassembler test cases.
4. HasNEON2 has the wrong assembler predicate.
rdar://10139676
llvm-svn: 154456
We were incorrectly conflating some add variants which don't have a
cc_out operand with the mirroring sub encodings, which do. Part of the
awesome non-orthogonality legacy of thumb1. Similarly, handling of
add/sub of an immediate was sometimes incorrectly removing the cc_out
operand for add/sub register variants.
rdar://11216577
llvm-svn: 154411
'add r2, #-1024' should just use 'sub r2, #1024' rather than erroring out.
Thumb1 aliases for adding a negative immediate to the stack pointer,
also.
rdar://11192734
llvm-svn: 154123
When an immediate is both a value [t2_]so_imm and a [t2_]so_imm_neg,
we want to use the non-negated form to make sure we prefer the normal
encoding, not the aliased encoding via the negation of, e.g., 'cmp.w'.
llvm-svn: 153770
For 'adds r2, r2, #56' outside of an IT block, the 16-bit encoding T2
can be used for this syntax. Prefer the narrow encoding when possible.
rdar://11156277
llvm-svn: 153759
* Removed test/lib/llvm.exp - it is no longer needed
* Deleted the dg.exp reading code from test/lit.cfg. There are no dg.exp files
left in the test suite so this code is no longer required. test/lit.cfg is
now much shorter and clearer
* Removed a lot of duplicate code in lit.local.cfg files that need access to
the root configuration, by adding a "root" attribute to the TestingConfig
object. This attribute is dynamically computed to provide the same
information as was previously provided by the custom getRoot functions.
* Documented the config.root attribute in docs/CommandGuide/lit.pod
llvm-svn: 153408
It's not a good style idea, as the registers will be laid down in memory in
numerical order, not the order they're in the list, but it's legal. vldm/vstm
are stricter.
rdar://11064740
llvm-svn: 152943
We on the linker to resolve calls to the appropriate BL/BLX instruction
to make interworking function correctly. It uses the symbol in the
relocation to do that, so we need to be careful about being too clever.
To enable this for ARM mode, split the BL/BLX fixup kind off from the
unconditional-branch fixups.
rdar://10927209
llvm-svn: 151571
This enables the linker to match concrete relocation types (absolute or relative) with whatever library or C++ support code is being linked against.
llvm-svn: 149057
"Although a Thumb2 instruction, the IT mnemonic shall be permitted in
ARM mode, and the condition verified to match the condition code(s)
on the following instruction(s)."
PR11853
llvm-svn: 148969
For bit patterns that aren't representable using the 8-bit floating point
representation for vmov.f32, but are representable via vmov.i32, treat
the .f32 syntax as an alias. Most importantly, this covers the case
'vmov.f32 Vd, #0.0'.
rdar://10616677
llvm-svn: 148556
"mov r1, r2, lsl #0" should assemble as "mov r1, r2" even though it's
not strictly legal UAL syntax. It's a common extension and the friendly
thing to do.
rdar://10604663
llvm-svn: 146937
Work in progress. Parsing for non-writeback, single spaced register lists
works now. The rest have the representations better factored, but still
need more to be able to parse properly.
llvm-svn: 146579
When 'cmp rn #imm' doesn't match due to the immediate not being representable,
but 'cmn rn, #-imm' does match, use the latter in place of the former, as
it's equivalent.
rdar://10552389
llvm-svn: 146567
When the immediate operand of an AND or BIC instruction isn't representable
in the immediate field of the instruction, but the bitwise negation of the
immediate is, assemble the instruction as the inverse operation instead
with the inverted immediate as the operand.
rdar://10550057
llvm-svn: 146283
Refactor the instructions into fixed writeback and register-stride
writeback variants to simplify the offset operand (no more optional
register operand using reg0). This is a simpler representation and allows
the assembly parser to more easily handle these instructions.
Add tests for the instruction variants now supported.
llvm-svn: 146278
We don't (yet) have the granularity in the fixups to be specific about which
bitranges are affected. That's a future cleanup, but we're not there yet.
llvm-svn: 144852
For example,
vld1.f64 {d2-d5}, [r2,:128]!
Should be equivalent to:
vld1.f64 {d2,d3,d4,d5}, [r2,:128]!
It's not documented syntax in the ARM ARM, but it is consistent with what's
accepted for VLDM/VSTM and is unambiguous in meaning, so it's a good thing to
support.
rdar://10451128
llvm-svn: 144727
When the 3rd operand is not a low-register, and the first two operands are
the same low register, the parser was incorrectly trying to use the 16-bit
instruction encoding.
rdar://10449281
llvm-svn: 144679
Mihai Popa