Commit Graph

248 Commits

Author SHA1 Message Date
Luke Cheeseman 6db3a6a4a7 Revert r347490 as it breaks address sanitizer builds
llvm-svn: 347499
2018-11-23 17:13:06 +00:00
Luke Cheeseman d6dbd64104 Revert r343341
- Cannot reproduce the build failure locally and the build logs have
  been deleted.

llvm-svn: 347490
2018-11-23 11:01:47 +00:00
Oliver Stannard c41902807e [AArch64][v8.5A] Add Memory Tagging instructions
This adds new instructions to manipluate tagged pointers, and to load
and store the tags associated with memory.

Patch by Pablo Barrio, David Spickett and Oliver Stannard!

Differential revision: https://reviews.llvm.org/D52490

llvm-svn: 343572
2018-10-02 10:04:39 +00:00
Oliver Stannard 4493f421ac [AArch64][v8.5A] Add MTE system instructions
The Memory Tagging Extension adds system instructions for data cache
maintenance, implemented as new operands to the DC instruction.

Patch by Pablo Barrio!

Differential revision: https://reviews.llvm.org/D52487

llvm-svn: 343570
2018-10-02 09:48:43 +00:00
Luke Cheeseman 10981cc884 Revert r343317
- asan buildbots are breaking and I need to investigate the issue

llvm-svn: 343341
2018-09-28 17:01:50 +00:00
Luke Cheeseman 21f2955bb2 Reapply changes reverted by r343235
- Add fix so that all code paths that create DWARFContext
  with an ObjectFile initialise the target architecture in the context
- Add an assert that the Arch is known in the Dwarf CallFrameString method

llvm-svn: 343317
2018-09-28 13:37:27 +00:00
Luke Cheeseman 8e5676b1aa Revert r343192 as an ubsan build is currently failing
llvm-svn: 343235
2018-09-27 16:47:30 +00:00
Oliver Stannard a9a5eee169 [AArch64][v8.5A] Add Branch Target Identification instructions
This adds new instructions used by the Branch Target Identification
feature. When this is enabled, these are the only instructions which can
be targeted by indirect branch instructions.

Patch by Pablo Barrio!

Differential revision: https://reviews.llvm.org/D52485

llvm-svn: 343225
2018-09-27 14:54:33 +00:00
Oliver Stannard 8459d34e82 [AArch64][v8.5A] Add speculation restriction system registers
This adds some new system registers which can be used to restrict
certain types of speculative execution.

Patch by Pablo Barrio and David Spickett!

Differential revision: https://reviews.llvm.org/D52482

llvm-svn: 343218
2018-09-27 14:05:46 +00:00
Oliver Stannard 6930b12d53 [AArch64][v8.5A] Add Armv8.5-A "DC CVADP" instruction
This adds a new variant of the DC system instruction for persistent
memory.

Patch by Pablo Barrio!

Differential revision: https://reviews.llvm.org/D52480

llvm-svn: 343216
2018-09-27 13:53:35 +00:00
Oliver Stannard 224428c06a [AArch64][v8.5A] Add prediction invalidation instructions to AArch64
This adds new system instructions which act as barriers to speculative
execution based on earlier execution within a particular execution
context.

Patch by Pablo Barrio!

Differential revision: https://reviews.llvm.org/D52479

llvm-svn: 343214
2018-09-27 13:47:40 +00:00
Luke Cheeseman f6844b307a Reapply changes reverted in r343114, lldb patch to follow shortly
llvm-svn: 343192
2018-09-27 10:39:20 +00:00
Luke Cheeseman 77aaa22081 Revert r343112 as CallFrameString API change has broken lldb builds
llvm-svn: 343114
2018-09-26 14:48:03 +00:00
Luke Cheeseman 03ad8812f5 [AArch64] - Return address signing dwarf support
- Reapply r343089 with a fix for DebugInfo/Sparc/gnu-window-save.ll

llvm-svn: 343112
2018-09-26 14:30:29 +00:00
Oliver Stannard 89b1604935 [AArch64][AsmParser] Show name of missing feature for system instructions
Parsing of the system instructions (IC, DC, AT and TLBI) uses this
function to show the required architecture when the operand is valid,
but the architecture is not enabled. Armv8.5A adds a few different
system instructions as part of optional features, so we need to extend
it to show individual features, not just base architectures.

This is NFC for now, but will be used by three different features added
in v8.5A, and will be tested by them.

Patch by David Spickett!

Differential revision: https://reviews.llvm.org/D52478

llvm-svn: 343109
2018-09-26 13:52:27 +00:00
Hans Wennborg 00b88bbcaf Revert r343089 "[AArch64] - Return address signing dwarf support"
This caused the DebugInfo/Sparc/gnu-window-save.ll test to fail.

> Functions that have signed return addresses need additional dwarf support:
> - After signing the LR, and before authenticating it, the LR register is in a
>   state the is unusable by a debugger or unwinder
> - To account for this a new directive, .cfi_negate_ra_state, is added
> - This directive says the signed state of the LR register has now changed,
>   i.e. unsigned -> signed or signed -> unsigned
> - This directive has the same CFA code as the SPARC directive GNU_window_save
>   (0x2d), adding a macro to account for multiply defined codes
> - This patch matches the gcc implementation of this support:
>   https://patchwork.ozlabs.org/patch/800271/
>
> Differential Revision: https://reviews.llvm.org/D50136

llvm-svn: 343103
2018-09-26 12:57:45 +00:00
Oliver Stannard 7c3c4baa3f [ARM/AArch64][v8.5A] Add Armv8.5-A target
This patch allows targeting Armv8.5-A, adding the architecture to
tablegen and setting the options to be identical to Armv8.4-A for the
time being. Subsequent patches will add support for the different
features included in the Armv8.5-A Reference Manual.

Patch by Pablo Barrio!

Differential revision: https://reviews.llvm.org/D52470

llvm-svn: 343102
2018-09-26 12:48:21 +00:00
Luke Cheeseman f755e687fc [AArch64] - Return address signing dwarf support
Functions that have signed return addresses need additional dwarf support:
- After signing the LR, and before authenticating it, the LR register is in a
  state the is unusable by a debugger or unwinder
- To account for this a new directive, .cfi_negate_ra_state, is added
- This directive says the signed state of the LR register has now changed,
  i.e. unsigned -> signed or signed -> unsigned
- This directive has the same CFA code as the SPARC directive GNU_window_save
  (0x2d), adding a macro to account for multiply defined codes
- This patch matches the gcc implementation of this support:
  https://patchwork.ozlabs.org/patch/800271/

Differential Revision: https://reviews.llvm.org/D50136

llvm-svn: 343089
2018-09-26 10:14:15 +00:00
David Green 85d6a55995 [AArch64] Attempt to parse more operands as expressions
This tries to make use of evaluateAsRelocatable in AArch64AsmParser::classifySymbolRef
to parse more complex expressions as relocatable operands. It is hopefully better than
the existing code which only handles Symbol +- Constant.

This allows us to parse more complex adr/adrp, mov, ldr/str and add operands. It also
loosens the requirements on parsing addends in ld/st and mov's and adds a number of
tests.

Differential Revision: https://reviews.llvm.org/D51792

llvm-svn: 342455
2018-09-18 09:44:53 +00:00
David Green 9dd1d451d9 [AArch64] Add Tiny Code Model for AArch64
This adds the plumbing for the Tiny code model for the AArch64 backend. This,
instead of loading addresses through the normal ADRP;ADD pair used in the Small
model, uses a single ADR. The 21 bit range of an ADR means that the code and
its statically defined symbols need to be within 1MB of each other.

This makes it mostly interesting for embedded applications where we want to fit
as much as we can in as small a space as possible.

Differential Revision: https://reviews.llvm.org/D49673

llvm-svn: 340397
2018-08-22 11:31:39 +00:00
Martin Storsjo d4590c38ab [AArch64] Disallow the MachO specific .loh directive for windows
Also add a test for it being unsupported for linux.

Differential Revision: https://reviews.llvm.org/D49929

llvm-svn: 338493
2018-08-01 06:50:18 +00:00
Martin Storsjo 3e3d39d07e [AArch64] Support the .inst directive for MachO and COFF targets
Contrary to ELF, we don't add any markers that distinguish data generated
with .long from normal instructions, so the .inst directive only adds
compatibility with assembly that uses it.

Differential Revision: https://reviews.llvm.org/D49935

llvm-svn: 338355
2018-07-31 09:26:52 +00:00
Sander de Smalen 9b33309c87 [AArch64][SVE] Asm: Add MOVPRFX instructions.
This patch adds predicated and unpredicated MOVPRFX instructions, which
can be prepended to SVE instructions that are destructive on their first
source operand, to make them a constructive operation, e.g.

  add z1.s, p0/m, z1.s, z2.s        <=> z1 = z1 + z2

can be made constructive:

  movprfx z0, z1
  add z0.s, p0/m, z0.s, z2.s        <=> z0 = z1 + z2

The predicated MOVPRFX instruction can additionally be used to zero
inactive elements, e.g.

  movprfx z0.s, p0/z, z1.s
  add z0.s, p0/m, z0.s, z2.s

Not all instructions can be prefixed with the MOVPRFX instruction
which is why this patch also adds a mechanism to validate prefixed
instructions. The exact rules when a MOVPRFX applies is detailed in
the SVE supplement of the Architectural Reference Manual.

This is patch [1/2] in a series to add MOVPRFX instructions:
- Patch [1/2]: https://reviews.llvm.org/D49592
- Patch [2/2]: https://reviews.llvm.org/D49593

Reviewers: rengolin, SjoerdMeijer, samparker, fhahn, javed.absar

Reviewed By: SjoerdMeijer

Differential Revision: https://reviews.llvm.org/D49592

llvm-svn: 338258
2018-07-30 15:42:46 +00:00
Sjoerd Meijer dc198344ce [AArch64] Armv8.2-A: add the crypto extensions
This adds MC support for the crypto instructions that were made optional
extensions in Armv8.2-A (AArch64 only).

Differential Revision: https://reviews.llvm.org/D49370

llvm-svn: 338010
2018-07-26 07:13:59 +00:00
Sander de Smalen c69944c6b0 [AArch64][SVE] Asm: Support for ADR instruction.
Supporting various addressing modes:
- adr z0.s, [z0.s, z0.s]
- adr z0.s, [z0.s, z0.s, lsl #<shift>]
- adr z0.d, [z0.d, z0.d]
- adr z0.d, [z0.d, z0.d, lsl #<shift>]
- adr z0.d, [z0.d, z0.d, uxtw #<shift>]
- adr z0.d, [z0.d, z0.d, sxtw #<shift>]

Reviewers: rengolin, fhahn, SjoerdMeijer, samparker, javed.absar

Reviewed By: SjoerdMeijer

Differential Revision: https://reviews.llvm.org/D48870

llvm-svn: 336533
2018-07-09 09:58:24 +00:00
Sjoerd Meijer a3dad801b7 Recommit: [AArch64] Armv8.4-A: Flag manipulation instructions
Now with the asm operand definition included.

llvm-svn: 336432
2018-07-06 12:32:33 +00:00
Sjoerd Meijer 2a57b357a3 [AArch64][ARM] Armv8.4-A: Trace synchronization barrier instruction
This adds the Armv8.4-A Trace synchronization barrier (TSB) instruction.

Differential Revision: https://reviews.llvm.org/D48918

llvm-svn: 336418
2018-07-06 08:03:12 +00:00
Simon Pilgrim 6dc45e6ca0 Try to fix -Wimplicit-fallthrough warning. NFCI.
llvm-svn: 336331
2018-07-05 09:48:01 +00:00
Sander de Smalen 592718f906 [AArch64][SVE] Asm: Support for signed/unsigned MIN/MAX/ABD
This patch implements the following varieties:

- Unpredicated signed max,   e.g. smax z0.h, z1.h, #-128
- Unpredicated signed min,   e.g. smin z0.h, z1.h, #-128

- Unpredicated unsigned max, e.g. umax z0.h, z1.h, #255
- Unpredicated unsigned min, e.g. umin z0.h, z1.h, #255

- Predicated signed max,     e.g. smax z0.h, p0/m, z0.h, z1.h
- Predicated signed min,     e.g. smin z0.h, p0/m, z0.h, z1.h
- Predicated signed abd,     e.g. sabd z0.h, p0/m, z0.h, z1.h

- Predicated unsigned max,   e.g. umax z0.h, p0/m, z0.h, z1.h
- Predicated unsigned min,   e.g. umin z0.h, p0/m, z0.h, z1.h
- Predicated unsigned abd,   e.g. uabd z0.h, p0/m, z0.h, z1.h

llvm-svn: 336317
2018-07-05 07:54:10 +00:00
Sander de Smalen e31e6d46dd [AArch64][SVE] Asm: Support for SVE condition code aliases
SVE overloads the AArch64 PSTATE condition flags and introduces
a set of condition code aliases for the assembler. The 
details are described in section 2.2 of the architecture
reference manual supplement for SVE.

In short:

  SVE alias =>  AArch64 name
  --------------------------
  NONE      => EQ
  ANY       => NE
  NLAST     => HS
  LAST      => LO
  FIRST     => MI
  NFRST     => PL
  PMORE     => HI
  PLAST     => LS
  TCONT     => GE
  TSTOP     => LT

Reviewers: rengolin, fhahn, SjoerdMeijer, samparker, javed.absar

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D48869

llvm-svn: 336245
2018-07-04 08:50:49 +00:00
Sander de Smalen 128fdfa23f [AArch64][SVE] Asm: Support for FP Complex ADD/MLA.
The variants added in this patch are:

- Predicated Complex floating point ADD with rotate, e.g.

   fcadd   z0.h, p0/m, z0.h, z1.h, #90

- Predicated Complex floating point MLA with rotate, e.g.

   fcmla   z0.h, p0/m, z1.h, z2.h, #180

- Unpredicated Complex floating point MLA with rotate (indexed operand), e.g.

   fcmla   z0.h, p0/m, z1.h, z2.h[0], #180

Reviewers: rengolin, fhahn, SjoerdMeijer, samparker, javed.absar

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D48824

llvm-svn: 336210
2018-07-03 16:01:27 +00:00
Sander de Smalen 8cd1f53334 [AArch64][SVE] Asm: Support for FMUL (indexed)
Unpredicated FP-multiply of SVE vector with a vector-element given by
vector[index], for example:

  fmul z0.s, z1.s, z2.s[0]

which performs an unpredicated FP-multiply of all 32-bit elements in
'z1' with the first element from 'z2'.

This patch adds restricted register classes for SVE vectors:
  ZPR_3b (only z0..z7 are allowed)  - for indexed vector of 16/32-bit elements.
  ZPR_4b (only z0..z15 are allowed) - for indexed vector of 64-bit elements.

Reviewers: rengolin, fhahn, SjoerdMeijer, samparker, javed.absar

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D48823

llvm-svn: 336205
2018-07-03 15:31:04 +00:00
Sjoerd Meijer 173b7f0ec7 [AArch64] Armv8.4-A: system registers
This adds the following system registers:
- RAS registers,
- MPAM registers,
- Activitiy monitor registers,
- Trace Extension registers,
- Timing insensitivity of data processing instructions,
- Enhanced Support for Nested Virtualization.

Differential Revision: https://reviews.llvm.org/D48871

llvm-svn: 336193
2018-07-03 12:09:20 +00:00
Sander de Smalen 8fcc3f5feb [AArch64][SVE] Asm: Support for vector element FP compare.
Contains the following variants:

- Compare with (elements from) other vector
  instructions: fcmeq, fcmgt, fcmge, fcmne, fcmuo.
  aliases: fcmle, fcmlt.

  e.g. fcmle   p0.h, p0/z, z0.h, z1.h => fcmge p0.h, p0/z, z1.h, z0.h

- Compare absolute values with (absolute values from) other vector.
  instructions: facge, facgt.
  aliases: facle, faclt.

  e.g. facle   p0.h, p0/z, z0.h, z1.h => facge   p0.h, p0/z, z1.h, z0.h

- Compare vector elements with #0.0
  instructions: fcmeq, fcmgt, fcmge, fcmle, fcmlt, fcmne.

  e.g. fcmle   p0.h, p0/z, z0.h, #0.0

llvm-svn: 336182
2018-07-03 09:07:23 +00:00
Sander de Smalen 0325e304b9 Reapply r334980 and r334983.
These patches were previously reverted as they led to 
buildbot time-outs caused by large switch statement in
printAliasInstr when using UBSan and O3.  The issue has
been addressed with a workaround (r335525).

llvm-svn: 336079
2018-07-02 07:34:52 +00:00
Vlad Tsyrklevich 98724e582e Revert r334980 and 334983
This reverts commits r334980 and r334983 because they were causing build
timeouts on the x86_64-linux-ubsan bot.

llvm-svn: 335085
2018-06-20 00:02:32 +00:00
Sander de Smalen 067eee1c13 [AArch64][SVE] Asm: Fix predicate pattern diagnostics.
This patch uses the DiagnosticPredicate for SVE predicate patterns
to improve their diagnostics, now giving a 'invalid operand' diagnostic
if the type is not an immediate or one of the expected pattern
labels.

Reviewers: samparker, SjoerdMeijer, javed.absar, fhahn

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D48220

llvm-svn: 334983
2018-06-18 21:03:02 +00:00
Sander de Smalen 7ac9e193ec [AArch64][SVE] Asm: Support for saturating INC/DEC (32bit scalar) instructions.
The variants added by this patch are:
- SQINC     signed increment, e.g. sqinc x0, w0, all, mul #4
- SQDEC     signed decrement, e.g. sqdec x0, w0, all, mul #4
- UQINC   unsigned increment, e.g. uqinc w0, all, mul #4
- UQDEC   unsigned decrement, e.g. uqdec w0, all, mul #4
 
This patch includes asmparser changes to parse a GPR64 as a GPR32 in
order to satisfy the constraint check:
  x0 == GPR64(w0)
in:
  sqinc x0, w0, all, mul #4
         ^___^ (must match)

Reviewers: rengolin, fhahn, SjoerdMeijer, samparker, javed.absar

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D47716

llvm-svn: 334980
2018-06-18 20:50:33 +00:00
Sander de Smalen 18ac8f9f25 [AArch64][SVE] Asm: Support for INC/DEC (scalar) instructions.
Increment/decrement scalar register by (scaled) element count given by
predicate pattern, e.g. 'incw x0, all, mul #4'.

Reviewers: rengolin, fhahn, SjoerdMeijer, samparker, javed.absar

Reviewed By: SjoerdMeijer

Differential Revision: https://reviews.llvm.org/D47713

llvm-svn: 334838
2018-06-15 15:47:44 +00:00
Sander de Smalen 5eb51d7495 [AArch64][SVE] Asm: Support for FADD, FMUL and FMAX immediate instructions.
Reviewers: rengolin, fhahn, SjoerdMeijer, samparker, javed.absar

Reviewed By: javed.absar

Differential Revision: https://reviews.llvm.org/D47712

llvm-svn: 334831
2018-06-15 13:57:51 +00:00
Sander de Smalen 3cbf171479 [AArch64][SVE] Asm: Add parsing/printing support for exact FP immediates.
Some instructions require of a limited set of FP immediates as operands,
for example '#0.5 or #1.0' for SVE's FADD instruction.

This patch adds support for parsing and printing such FP immediates as
exact values (e.g. #0.499999 is not accepted for #0.5).

Reviewers: rengolin, fhahn, SjoerdMeijer, samparker, javed.absar

Reviewed By: SjoerdMeijer

Differential Revision: https://reviews.llvm.org/D47711

llvm-svn: 334826
2018-06-15 13:11:49 +00:00
Sander de Smalen d0a6f6a502 [AArch64][SVE] Fix range for DUP immediates (16bit elts)
For immediates used in DUP instructions that have the range
-128 to 127, or a multiple of 256 in the range -32768 to 32512,
one could argue that when the result element size is 16bits (.h),
the value can be considered both signed and unsigned.

Reviewers: rengolin, fhahn, SjoerdMeijer, samparker, javed.absar

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D47619

llvm-svn: 333873
2018-06-04 07:24:23 +00:00
Sander de Smalen fd54a781f6 [AArch64][SVE] Asm: Print indexed element 0 as FPR.
Print the first indexed element as a FP register, for example:

  mov z0.d, z1.d[0]

Is now printed as:

  mov z0.d, d1

Next to printing, this patch also adds aliases to parse 'mov z0.d, d1'.

Reviewers: rengolin, fhahn, samparker, SjoerdMeijer, javed.absar

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D47571

llvm-svn: 333872
2018-06-04 07:07:35 +00:00
Sander de Smalen c33d668ab7 [AArch64][SVE] Asm: Support for indexed DUP instructions.
Unpredicated copy of indexed SVE element to SVE vector,
along with MOV-aliases.

For example:

  dup     z0.h, z1.h[0]

duplicates the first 16-bit element from z1 to all elements in
the result vector z0.

Reviewers: rengolin, fhahn, samparker, SjoerdMeijer, javed.absar

Reviewed By: SjoerdMeijer

Differential Revision: https://reviews.llvm.org/D47570

llvm-svn: 333871
2018-06-04 06:40:55 +00:00
Sander de Smalen 97ca6b9e09 [AArch64][SVE] Asm: Support for DUPM (masked immediate) instruction.
Unpredicated copy of repeating immediate pattern to SVE vector, along
with MOV-aliases.

Reviewers: rengolin, fhahn, samparker, SjoerdMeijer, javed.absar

Reviewed By: SjoerdMeijer

Differential Revision: https://reviews.llvm.org/D47328

llvm-svn: 333731
2018-06-01 07:25:46 +00:00
Sander de Smalen bdf09fe7a2 [AArch64][AsmParser] Fix segfault on illegal fpimm.
Floating point immediate combining a negative sign and
a hexadecimal number, e.g. #-0x0  caused the compiler to crash.

Reviewers: rengolin, fhahn, samparker, SjoerdMeijer, javed.absar

Reviewed By: javed.absar

Differential Revision: https://reviews.llvm.org/D47483

llvm-svn: 333524
2018-05-30 09:54:19 +00:00
Sander de Smalen 98686c6b15 [AArch64][SVE] Asm: Support for ADD (immediate) instructions.
This patch adds addsub_imm8_opt_lsl_(i8|i16|i32|i64) operands
that are unsigned values in the range 0 to 255. For element widths of
16 bits or higher it may also be a signed multiple of 256 in the
range 0 to 65280.

Note: This also does some refactoring to reuse convenience function
getShiftedVal<shift>(), and now allows AArch64 scalar 'ADD #-4096' to be
accepted to be mapped to SUB #4096.

Reviewers: rengolin, fhahn, samparker, SjoerdMeijer, javed.absar

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D47310

llvm-svn: 333408
2018-05-29 10:39:49 +00:00
Sander de Smalen 6e2a5b4cf0 Fix ubsan errors introduced by r333263 re. left-shifting negative values.
llvm-svn: 333270
2018-05-25 11:41:04 +00:00
Sander de Smalen 62770795a5 [AArch64][SVE] Asm: Support for DUP (immediate) instructions.
Unpredicated copy of optionally-shifted immediate to SVE vector,
along with MOV-aliases.

This patch contains parsing and printing support for
cpy_imm8_opt_lsl_(i8|i16|i32|i64). This operand allows a signed value in
the range -128 to +127. For element widths of 16 bits or higher it may
also be a signed multiple of 256 in the range -32768 to +32512.
For element-width of 8 bits a range of -128 to 255 is accepted, since a copy
of a byte can be considered either signed/unsigned.

Note: This patch renames tryParseAddSubImm() -> tryParseImmWithOptionalShift()
and moves the behaviour of trying to shift a plain immediate by an allowed
shift-value to its addImmWithOptionalShiftOperands() method, so that the
parsing itself is generic and allows immediates from multiple shifted operands.
This is done because an immediate can be divisible by both shifted operands.

Reviewers: rengolin, fhahn, samparker, SjoerdMeijer, javed.absar

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D47309

llvm-svn: 333263
2018-05-25 09:47:52 +00:00
Alex Bradbury 0a59f18951 [AArch64] Use addAliasForDirective to support data directives
The AArch64 asm parser currently has custom parsing logic for .hword, .word, 
and .xword. Rather than use this custom logic, we can just use 
addAliasForDirective to enable the reuse of AsmParser::parseDirectiveValue.

Differential Revision: https://reviews.llvm.org/D47000

llvm-svn: 333077
2018-05-23 11:17:20 +00:00