Commit Graph

106192 Commits

Author SHA1 Message Date
Eli Bendersky
6a33571ba9 Use CHECK-LABEL where appropriate in this test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213398 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 19:32:09 +00:00
Mark Heffernan
8ec1546db4 Add loop unrolling metadata descriptions to docs/LangRef.rst.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213397 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 19:24:51 +00:00
Gerolf Hoflehner
d94715e273 MergedLoadStoreMotion pass
Merges equivalent loads on both sides of a hammock/diamond
and hoists into into the header.
Merges equivalent stores on both sides of a hammock/diamond
and sinks it to the footer.
Can enable if conversion and tolerate better load misses
and store operand latencies.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213396 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 19:13:09 +00:00
David Blaikie
63d94561b5 Reapply "DebugInfo: Ensure that all debug location scope chains from instructions within a function, lead to the function itself."""
Recommits 212776 which was reverted in r212793. This has been committed
and recommitted a few times as I try to test it harder and find/fix more
issues. The most recent revert was due to an asan bot failure which I
can't seem to reproduce locally, though I believe I'm following all the
steps the buildbot does.

So I'm going to recommit this in the hopes of investigating the failure
on the buildbot itself... apologies in advance for the bot noise. If
anyone sees failures with this /please/ provide me with any
reproductions, etc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213391 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 17:49:10 +00:00
David Peixotto
bb10524098 Fix build failure on windows
Add explicit constructor to struct instead of using brace initialization.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213389 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 16:41:58 +00:00
David Peixotto
12f33da20b MC: support different sized constants in constant pools
On AArch64 the pseudo instruction ldr <reg>, =... supports both
32-bit and 64-bit constants. Add support for 64 bit constants for
the pools to support the pseudo instruction fully.

Changes the AArch64 ldr-pseudo tests to use 32-bit registers and
adds tests with 64-bit registers.

Patch by Janne Grunau!

Differential Revision: http://reviews.llvm.org/D4279



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213387 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 16:05:14 +00:00
Hal Finkel
11af4b49b2 Add a dereferenceable attribute
This attribute indicates that the parameter or return pointer is
dereferenceable. Practically speaking, loads from such a pointer within the
associated byte range are safe to speculatively execute. Such pointer
parameters are common in source languages (C++ references, for example).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213385 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 15:51:28 +00:00
Daniel Sanders
a11bf68f6c Add MIPS Technologies to the vendors in llvm::Triple.
This is a prerequisite for checking for 'mti' and 'img' in a consistent way in
clang. Previously 'img' could use Triple::getVendor() but 'mti' could only use
Triple::getVendorName().



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213381 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 14:28:19 +00:00
Tim Northover
e72ff8829e AArch64: implement efficient f16 bitcasts
Because i16 is illegal, there's no native DAG method to
represent a bitcast to or from an f16 type. This meant LLVM was
inserting a stack store/load pair which is really not ideal.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213378 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 13:07:05 +00:00
Tim Northover
b41b1d4bac NVPTX: support fpext/fptrunc to and from f16.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213377 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 13:01:43 +00:00
Tim Northover
7714a60ed1 R600: support fpext/fptrunc operations to and from f16.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213376 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 13:01:37 +00:00
Tim Northover
1a8bcdb72e AArch64: support f16 extend/trunc operations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213375 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 13:01:31 +00:00
Tim Northover
e683321270 X86: support fpext/fptrunc operations to and from 16-bit floats.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213374 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 13:01:25 +00:00
Tim Northover
4413539ee4 ARM: support legalisation of "fptrunc ... to half" operations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213373 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 13:01:19 +00:00
Tim Northover
0afed03229 CodeGen: soften f16 type by default instead of marking legal.
Actual support for softening f16 operations is still limited, and can be added
when it's needed.  But Soften is much closer to being a useful thing to try
than keeping it Legal when no registers can actually hold such values.

Longer term, we probably want something between Soften and Promote semantics
for most targets, it'll be more efficient to promote the 4 basic operations to
f32 than libcall them.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213372 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 12:41:46 +00:00
Renato Golin
dc80347f0e Suppress 'not handled in switch' warning
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213371 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 12:13:04 +00:00
Tilmann Scheller
7cd0201f02 [ARM] Add earlyclobber constraint to pre/post-indexed ARM STR instructions.
The post-indexed instructions were missing the constraint, causing unpredictable STR instructions to be emitted.

The earlyclobber constraint on the pre-indexed STR instructions is not strictly necessary, as the instruction selection for pre-indexed STR instructions goes through an additional layer of pseudo instructions which have the constraint defined, however it doesn't hurt to specify the constraint directly on the pre-indexed instructions as well, since at some point someone might create instances of them programmatically and then the constraint is definitely needed.

This fixes PR20323.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213369 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 12:05:49 +00:00
Renato Golin
03ac7db89d Refactor ARM subarchitecture parsing
Re-commit of a patch to rework the triple parsing on ARM to a more sane
model.

Patch by Gabor Ballabas.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213367 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 12:00:48 +00:00
Artyom Skrobov
11c20581d6 extracting swapStruct into include/llvm/Support/MachO.h (no functional change)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213361 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 09:26:16 +00:00
Tim Northover
f811b2895f R600: rename misleading fp16 test.
This test is actually going in the opposite direction to what the
filename and function name suggested.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213358 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 08:43:30 +00:00
Tim Northover
cc03227446 R600: support f16 -> f64 conversion intrinsic.
Unfortunately, we don't seem to have a direct truncation, but the
extension can be legally split into two operations so we should
support that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213357 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 08:43:24 +00:00
Tim Northover
7bbf5786d7 NVPTX: support direct f16 <-> f64 conversions via intrinsics.
Clang may well start emitting these soon, and while it may not be
directly relevant for OpenCL or GLSL, the instructions were just
sitting there waiting to be used.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213356 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 08:30:10 +00:00
Hal Finkel
d0261683e8 Rename AlignAttribute to IntAttribute
Currently the only kind of integer IR attributes that we have are alignment
attributes, and so the attribute kind that takes an integer parameter is called
AlignAttr, but that will change (we'll soon be adding a dereferenceable
attribute that also takes an integer value). Accordingly, rename AlignAttribute
to IntAttribute (class names, enums, etc.).

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213352 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 06:51:55 +00:00
Matt Arsenault
a32c319741 R600: Implement TTI:getPopcntSupport
The test is just copied from X86, and I don't know of a better
way to test it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213351 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 06:07:13 +00:00
Jim Grosbach
c6058e2462 X86: Constant fold converting vector setcc results to float.
Since the result of a SETCC for X86 is 0 or -1 in each lane, we can
move unary operations, in this case [su]int_to_fp through the mask
operation and constant fold the operation away. Generally speaking:
  UNARYOP(AND(VECTOR_CMP(x,y), constant))
      --> AND(VECTOR_CMP(x,y), constant2)
where constant2 is UNARYOP(constant).

This implements the transform where UNARYOP is [su]int_to_fp.

For example, consider the simple function:
define <4 x float> @foo(<4 x float> %val, <4 x float> %test) nounwind {
  %cmp = fcmp oeq <4 x float> %val, %test
  %ext = zext <4 x i1> %cmp to <4 x i32>
  %result = sitofp <4 x i32> %ext to <4 x float>
  ret <4 x float> %result
}

Before this change, the SSE code is generated as:
LCPI0_0:
  .long 1                       ## 0x1
  .long 1                       ## 0x1
  .long 1                       ## 0x1
  .long 1                       ## 0x1
  .section  __TEXT,__text,regular,pure_instructions
  .globl  _foo
  .align  4, 0x90
_foo:                                   ## @foo
  cmpeqps %xmm1, %xmm0
  andps LCPI0_0(%rip), %xmm0
  cvtdq2ps  %xmm0, %xmm0
  retq

After, the code is improved to:
LCPI0_0:
  .long 1065353216              ## float 1.000000e+00
  .long 1065353216              ## float 1.000000e+00
  .long 1065353216              ## float 1.000000e+00
  .long 1065353216              ## float 1.000000e+00
  .section  __TEXT,__text,regular,pure_instructions
  .globl  _foo
  .align  4, 0x90
_foo:                                   ## @foo
  cmpeqps %xmm1, %xmm0
  andps LCPI0_0(%rip), %xmm0
  retq

The cvtdq2ps has been constant folded away and the floating point 1.0f
vector lanes are materialized directly via the ModRM operand of andps.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213342 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 00:40:56 +00:00
Jim Grosbach
f4e104f5eb AArch64: Constant fold converting vector setcc results to float.
Since the result of a SETCC for AArch64 is 0 or -1 in each lane, we can
move unary operations, in this case [su]int_to_fp through the mask
operation and constant fold the operation away. Generally speaking:
  UNARYOP(AND(VECTOR_CMP(x,y), constant))
      --> AND(VECTOR_CMP(x,y), constant2)
where constant2 is UNARYOP(constant).

This implements the transform where UNARYOP is [su]int_to_fp.

For example, consider the simple function:
define <4 x float> @foo(<4 x float> %val, <4 x float> %test) nounwind {
  %cmp = fcmp oeq <4 x float> %val, %test
  %ext = zext <4 x i1> %cmp to <4 x i32>
  %result = sitofp <4 x i32> %ext to <4 x float>
  ret <4 x float> %result
}

Before this change, the code is generated as:
  fcmeq.4s  v0, v0, v1
  movi.4s v1, #0x1        // Integer splat value.
  and.16b v0, v0, v1      // Mask lanes based on the comparison.
  scvtf.4s  v0, v0        // Convert each lane to f32.
  ret

After, the code is improved to:
  fcmeq.4s  v0, v0, v1
  fmov.4s v1, #1.00000000 // f32 splat value.
  and.16b v0, v0, v1      // Mask lanes based on the comparison.
  ret

The svvtf.4s has been constant folded away and the floating point 1.0f
vector lanes are materialized directly via fmov.4s.

Rather than do the folding manually in the target code, teach getNode()
in the generic SelectionDAG to handle folding constant operands of
vector [su]int_to_fp nodes. It is reasonable (as noted in a FIXME) to do
additional constant folding there as well, but I don't have test cases
for those operations, so leaving them for another time when it becomes
appropriate.

rdar://17693791

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213341 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 00:40:52 +00:00
Michael J. Spencer
f2c19f622f Revert "[x86] Fold extract_vector_elt of a load into the Load's address computation."
There's a bug where this can create cycles in the DAG. It will take a bit
to fix, so I'm backing it out for now.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213339 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 00:15:50 +00:00
Eric Christopher
f0b9d0b3ca Reset the Subtarget in the AsmPrinter for each machine function
and add explanatory comment about dual initialization. Fix
use of the Subtarget to grab the information off of the target machine.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213336 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 00:08:53 +00:00
Eric Christopher
a1fa640525 Avoid resetting the UseSoftFloat and FloatABIType on the TargetMachine
Options struct and move the comment to inMips16HardFloat. Use the
fact that we now know whether or not we cared about soft float to
set the libcalls.
Accordingly rename mipsSEUsesSoftFloat to abiUsesSoftFloat and
propagate since it's no longer CPU specific.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213335 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-18 00:08:50 +00:00
Lang Hames
353cec5eba [MCJIT] Fix the alignment requirements for ARM and AArch64 which were mistakenly
relaxed in the big RuntimeDyldMachO cleanup of r213293.

No test case yet - this was found via inspection and there's no easy way to test
GOT alignment in RuntimeDyldChecker at the moment. I'm working on adding support
for this now, and hope to have a test case for this soon.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213331 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 23:11:30 +00:00
Kevin Enderby
79785e4352 Tweak formating to match what clang-format would be for llvm-nm.cpp .
No functional change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213330 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 22:56:27 +00:00
Kevin Enderby
c61aa0219e Add printing of Mach-O stabs in llvm-nm.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213327 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 22:47:16 +00:00
Reid Kleckner
5d83e5bdd5 Remove rules against std::function from the programmer's manual
Clarify that llvm::function_ref is like StringRef for callables.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213326 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 22:43:00 +00:00
Nico Weber
c1ef24ce39 ms inline asm: Don't add x86 segment registers to the clobber list.
Clang tries to check the clobber list but doesn't list segment registers in its
x86 register list. This fixes PR20343.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213303 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 20:24:55 +00:00
Lang Hames
822f1b191a Make myself code owner of MCJIT.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213302 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 20:23:31 +00:00
Alp Toker
3cf9f37312 Drop the udis86 wrapper from llvm::sys
This optional dependency on the udis86 library was added some time back to aid
JIT development, but doesn't make much sense to link into LLVM binaries these
days.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213300 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 20:05:29 +00:00
Reid Kleckner
55ebcf372d TableGen: Add 'static' to a large array to avoid a huge stack allocation
Speculative fix for a -Wframe-larger-than warning from gcc.  Clang will
implicitly promote such constant arrays to globals, so in theory it
won't hit this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213298 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 19:43:40 +00:00
Arnaud A. de Grandmaison
08f689e9b0 [AArch64] Cleanup AsmParser: no need to use dyn_cast + assert. cast does it for us.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213296 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 19:08:14 +00:00
Suyog Sarda
adf8ae4c10 Rectify r213231. Use proper version of 'ComputeNumSignBits'.
Earlier when the code was in InstCombine, we were calling the version of ComputeNumSignBits in InstCombine.h
that automatically added the DataLayout* before calling into ValueTracking.
When the code moved to InstSimplify, we are calling into ValueTracking directly without passing in the DataLayout*.
This patch rectifies the same by passing DataLayout in ComputeNumSignBits.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213295 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 19:07:00 +00:00
Lang Hames
be406de225 [MCJIT] Significantly refactor the RuntimeDyldMachO class.
The previous implementation of RuntimeDyldMachO mixed logic for all targets
within a single class, creating problems for readability, maintainability, and
performance. To address these issues, this patch strips the RuntimeDyldMachO
class down to just target-independent functionality, and moves all
target-specific functionality into target-specific subclasses RuntimeDyldMachO.

The new class hierarchy is as follows:

class RuntimeDyldMachO
Implemented in RuntimeDyldMachO.{h,cpp}
Contains logic that is completely independent of the target. This consists
mostly of MachO helper utilities which the derived classes use to get their
work done.


template <typename Impl>
class RuntimeDyldMachOCRTPBase<Impl> : public RuntimeDyldMachO
Implemented in RuntimeDyldMachO.h
Contains generic MachO algorithms/data structures that defer to the Impl class
for target-specific behaviors.

RuntimeDyldMachOARM : public RuntimeDyldMachOCRTPBase<RuntimeDyldMachOARM>
RuntimeDyldMachOARM64 : public RuntimeDyldMachOCRTPBase<RuntimeDyldMachOARM64>
RuntimeDyldMachOI386 : public RuntimeDyldMachOCRTPBase<RuntimeDyldMachOI386>
RuntimeDyldMachOX86_64 : public RuntimeDyldMachOCRTPBase<RuntimeDyldMachOX86_64>
Implemented in their respective *.h files in lib/ExecutionEngine/RuntimeDyld/MachOTargets
Each of these contains the relocation logic specific to their target architecture.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213293 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 18:54:50 +00:00
Alexey Samsonov
30ea42931a [ASan] Don't instrument load/stores with !nosanitize metadata.
This is used to avoid instrumentation of instructions added by UBSan
in Clang frontend (see r213291). This fixes PR20085.

Reviewed in http://reviews.llvm.org/D4544.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213292 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 18:48:12 +00:00
Hans Wennborg
c636a42d4a Typo: exists -> exits
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213290 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 18:33:44 +00:00
Justin Holewinski
11ae250ec9 [NVPTX] Improve handling of FP fusion
We now consider the FPOpFusion flag when determining whether
to fuse ops.  We also explicitly emit add.rn when fusion is
disabled to prevent ptxas from fusing the operations on its
own.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213287 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 18:10:09 +00:00
Matt Arsenault
15865afcf7 Fix typos
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213285 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 17:50:22 +00:00
Zinovy Nis
345cb09610 [BUG] Due to a typo introduced in r199933 and r200027 two tests for FMA were never even started.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213283 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 17:14:35 +00:00
Adam Nemet
6ae2941874 [X86] AVX512: Add disassembler support for compressed displacement
There are two parts here.  First is to modify tablegen to adjust the encoding
type ENCODING_RM with the scaling factor.

The second is to use the new encoding types to compute the correct
displacement in the decoder.

Fixes <rdar://problem/17608489>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213281 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 17:04:56 +00:00
Adam Nemet
f166cc13e2 [X86] AVX512: Rename EVEX_CD8V to CD8_Form
This is to match the naming of CD8_EltSize, CD8_Scale, etc.

No functional change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213280 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 17:04:52 +00:00
Adam Nemet
5c6e7de1ad [X86] AVX512: Use the TD version of CD8_Scale in the assembler
Passes the computed scaling factor in TSFlags rather than the old attributes.

Also removes the C++ version of computing the scaling factor (MemObjSize)
along with the asserts added by the previous patch.

No functional change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213279 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 17:04:50 +00:00
Adam Nemet
ccba8025da [X86] AVX512: Move compressed displacement logic to TD
This does not actually move the logic yet but reimplements it in the Tablegen
language.  Then asserts that the new implementation results in the same value.

The next patch will remove the assert and the temporary use of the TSFlags and
remove the C++ implementation.

The formula requires a limited form of the logical left and right operators.
I implemented these with the bit-extract/insert operator (i.e. blah{bits}).

No functional change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213278 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 17:04:34 +00:00
Adam Nemet
30cced119b [TableGen] Allow shift operators to take bits<n>
Convert the operand to int if possible, i.e. if the value is properly
initialized.  (I suppose there is further room for improvement here to also
peform the shift if the uninitialized bits are shifted out.)

With this little change we can now compute the scaling factor for compressed
displacement with pure tablegen code in the X86 backend.  This is useful
because both the X86-disassembler-specific part of tablegen and the assembler
need this and TD is the natural sharing place.

The patch also adds the missing documentation for the shift and add operator.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213277 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 17:04:27 +00:00