Commit Graph

154 Commits

Author SHA1 Message Date
Stefan Maksimovic 6ccbd16433 [mips] Handle missing CondCodes
Add patterns for unhandled CondCode enumerables:
SETEQ, SETGE, SETGT, SETLE, SETLT, SETNE.

Stated at the ISD::CondCode enum declaration:
`All of these (except for the 'always folded ops')
should be handled for floating point.`

Add patterns which use these nodes, same as corresponding
'ordered' CondCode nodes.

Referring to 'Ordered means that neither operand is a QNAN'
we assume it is safe to match ex. SETLT node to the same
instruction as SETOLT.

Differential Revision: https://reviews.llvm.org/D50757

llvm-svn: 340392
2018-08-22 09:34:44 +00:00
Simon Atanasyan 738a6e449e [mips] Eliminate the usage of hasStdEnc in MipsPat.
Instead, the pattern is tagged with the correct predicate when
it is declared. Some patterns have been duplicated as necessary.

Patch by Simon Dardis.

Differential revision: https://reviews.llvm.org/D48365

llvm-svn: 337171
2018-07-16 13:52:41 +00:00
Simon Atanasyan 053ff54478 [mips] Mark standard encoded instructions as not being in MIPS16e
Mark standard encoded instructions and pseudo "standard encoded"
as not being in MIPS16e by default.

Patch by Simon Dardis.

Differential revision: https://reviews.llvm.org/D48379

llvm-svn: 336893
2018-07-12 08:50:11 +00:00
Petar Jovanovic c051000b83 [X86][MIPS][ARM] New machine instruction property 'isMoveReg'
This property is needed in order to follow values movement between
registers. This property is used in TII to implement method that
returns true if simple copy like instruction is recognized, along
with source and destination machine operands.

Patch by Nikola Prica.

Differential Revision: https://reviews.llvm.org/D45204

llvm-svn: 333093
2018-05-23 15:28:28 +00:00
Stefan Maksimovic c7113cc9e4 [mips][msa] Pattern match the splat.d instruction
Introduced a new pattern for matching splat.d explicitly.

Both splat.d and splati.d can now be generated from the @llvm.mips.splat.d
intrinsic depending on whether an immediate value has been passed.

Differential Revision: https://reviews.llvm.org/D45683

llvm-svn: 331771
2018-05-08 15:12:29 +00:00
Aleksandar Beserminji 3546c1603a [mips] Fix how compiler fuse instructions to fmadd/fmsub
This patch makes compiler does not fuse fmul and fadd/fsub into
fmadd/fmsub by default. Instead, -fp-contract=fast option can
be used when such behavior is desired.

Differential Revision: https://reviews.llvm.org/D46057

llvm-svn: 331033
2018-04-27 13:30:27 +00:00
Simon Pilgrim 386b8ddd5f [MIPS][MSA] Convert vector integer min/max opcodes to use generic implementation
Found while investigating D43338

Simon^3 - the LLVM project needs more Simons.

Differential Revision: https://reviews.llvm.org/D43433

llvm-svn: 325447
2018-02-17 21:29:45 +00:00
Petar Jovanovic 2b6fe3ffa6 [mips][msa] Mask vectors holding shift amounts
Masked vectors which hold shift amounts when creating the following nodes:
ISD::SHL, ISD::SRL or ISD::SRA.
Instructions that use said nodes, which have had their arguments altered are
sll, srl, sra, bneg, bclr and bset.

For said instructions, the shift amount or the bit position that is
specified in the corresponding vector elements will be interpreted as the
shift amount/bit position modulo the size of the element in bits.

The problem lies in compiling with -O2 enabled, where the instructions for
formats .w and .d are not generated, but are instead optimized away.
In this case, having shift amounts that are either negative or greater than
the element bit size results in generation of incorrect results when
constant folding.

We remedy this by masking the operands for the nodes mentioned above before
actually creating them, so that the final result is correct before placed
into the constant pool.

Patch by Stefan Maksimovic.

Differential Revision: https://reviews.llvm.org/D31331

llvm-svn: 300839
2017-04-20 13:26:46 +00:00
Simon Dardis 0e2ee3b4b9 [mips][msa] Implement f16 support
The MIPS MSA ASE provides instructions to convert to and from half precision
floating point. This patch teaches the MIPS backend to treat f16 as a legal
type and how to promote such values to f32 for the usual set of operations.

As a result of this, the fexup[lr].w intrinsics no longer crash LLVM during
type legalization.

Reviewers: zoran.jovanvoic, vkalintiris

Differential Revision: https://reviews.llvm.org/D26398

llvm-svn: 287349
2016-11-18 16:17:44 +00:00
Peter Collingbourne 2261d78cd2 Target: Remove unused patterns and transforms. NFC.
llvm-svn: 283515
2016-10-07 00:30:49 +00:00
Hrvoje Varga 00d96ee7b9 [mips] Clang generates unaligned offset for MSA instruction st.d
Differential Revision: https://reviews.llvm.org/D19475

llvm-svn: 277323
2016-08-01 06:46:20 +00:00
Simon Dardis b8dc8485c3 [mips] Add instruction itineraries for LSA, DLSA
Reviewers: vkalintiris, dsanders

Differential Review: http://reviews.llvm.org/D21679

llvm-svn: 273883
2016-06-27 14:55:07 +00:00
Daniel Sanders dc0602a2c2 [mips] Split mem_msa into range checked mem_simm10 and mem_simm10_lsl[123]
Summary:
Also, made test_mi10.s formatting consistent with the majority of the
MC tests.

Reviewers: vkalintiris

Subscribers: dsanders, llvm-commits

Differential Revision: http://reviews.llvm.org/D18435

llvm-svn: 265014
2016-03-31 14:12:01 +00:00
Daniel Sanders 15f8fb6f83 [mips] Range check vsplat_simm5 and vsplat_simm10
Summary:

Reviewers: vkalintiris

Subscribers: llvm-commits, dsanders

Differential Revision: http://reviews.llvm.org/D18177

llvm-svn: 264287
2016-03-24 14:53:40 +00:00
Daniel Sanders 0f17d0da4a [mips] Range check simm5.
Summary:
We can't check the error message for this one because there's another lw/sw
available that covers a larger range. We therefore check the transition
between the two sizes.

Reviewers: vkalintiris

Subscribers: llvm-commits, dsanders

Differential Revision: http://reviews.llvm.org/D18144

llvm-svn: 264054
2016-03-22 14:29:53 +00:00
Daniel Sanders 946dee3b5b [mips] Range check vsplat_uimm[1234568].
Summary:

Reviewers: vkalintiris

Subscribers: dsanders, llvm-commits

Differential Revision: http://reviews.llvm.org/D18143

llvm-svn: 264053
2016-03-22 14:17:41 +00:00
Daniel Sanders 93fa4ce9b7 [mips] Range check uimm4_ptr, remove uimm6_ptr, and use correctly sized immediates in MSA copy/insert.
Reviewers: vkalintiris

Subscribers: dsanders, llvm-commits

Differential Revision: http://reviews.llvm.org/D18142

llvm-svn: 264052
2016-03-22 13:58:53 +00:00
Daniel Sanders 03a8d2f8ec [mips] Range check uimm20 and fixed a bug this revealed.
Summary:
The bug was that dextu's operand 3 would print 0-31 instead of 32-63 when
printing assembly. This came up when replacing
MipsInstPrinter::printUnsignedImm() with a version that could handle arbitrary
bit widths.

MipsAsmPrinter::printUnsignedImm*() don't seem to be used so they have been
removed.

Reviewers: vkalintiris

Subscribers: dsanders, llvm-commits

Differential Revision: http://reviews.llvm.org/D15521

llvm-svn: 262231
2016-02-29 16:06:38 +00:00
Daniel Sanders 106d2d4693 [mips][ias] Range check uimm8 operands
Summary:

Reviewers: vkalintiris

Subscribers: llvm-commits, dsanders

Differential Revision: http://reviews.llvm.org/D15226

llvm-svn: 255018
2015-12-08 14:42:10 +00:00
Daniel Sanders 59d092f883 [mips][ias] Range check uimm6 operands and fix a bug this revealed.
Summary:
We don't check the size operand on ext/dext*/ins/dins* yet because the
permitted range depends on the pos argument and we can't check that using
this mechanism.

The bug was that dextu/dinsu accepted 0..31 in the pos operand instead of 32..63.

Reviewers: vkalintiris

Subscribers: llvm-commits, dsanders

Differential Revision: http://reviews.llvm.org/D15190

llvm-svn: 255015
2015-12-08 13:49:19 +00:00
Daniel Sanders 5762a4f9d1 [mips][ias] Range check uimm4 operands and fixed a bug this revealed.
Summary:
The bug was that the sldi instructions have immediate widths dependant on
their element size. So sldi.d has a 1-bit immediate and sldi.b has a 4-bit
immediate. All of these were using 4-bit immediates previously.

Reviewers: vkalintiris

Subscribers: llvm-commits, atanasyan, dsanders

Differential Revision: http://reviews.llvm.org/D14018

llvm-svn: 252297
2015-11-06 12:41:43 +00:00
Daniel Sanders ea4f653d18 [mips][ias] Range check uimm2 operands and fix a bug this revealed.
Summary:
The bug was that the MIPS32R6/MIPS64R6/microMIPS32R6 versions of LSA and DLSA
(unlike the MSA version) failed to account for the off-by-one encoding of the
immediate. The range is actually 1..4 rather than 0..3.

Reviewers: vkalintiris

Subscribers: atanasyan, dsanders, llvm-commits

Differential Revision: http://reviews.llvm.org/D14015

llvm-svn: 252295
2015-11-06 12:22:31 +00:00
Daniel Sanders 0f596814e9 [mips][msa] Remove copy_u.d and move copy_u.w to MSA64.
Summary:
The forwards compatibility strategy employed by MIPS is to consider registers
to be infinitely sign-extended. Then on ISA's with a wider register, the result
of existing instructions are sign-extended to register width and zero-extended
counterparts are added. copy_u.w on MSA32 and copy_u.w on MSA64 violate this
strategy and we have therefore corrected the MSA specs to fix this.

We still keep track of sign/zero-extension during legalization but we now
match copy_s.[wd] where required.

No change required to clang since __builtin_msa_copy_u_[wd] will map to
copy_s.[wd] where appropriate for the target.

Reviewers: vkalintiris

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D13472

llvm-svn: 250887
2015-10-21 09:58:54 +00:00
Daniel Sanders 090f6e41c4 [mips] Use PredicateControl for the MSA ASE instructions. NFC.
Reviewers: vkalintiris

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D13092

llvm-svn: 248486
2015-09-24 12:10:23 +00:00
Daniel Sanders 86cce70010 [mips][sched] Split IIBranch into specific instruction classes.
Summary:
Almost no functional change since the InstrItinData's have been duplicated.
The one functional change is to remove IIBranch from the MSA branches. The
classes will be assigned to the MSA instructions as part of implementing
the P5600 scheduler.

II_IndirectBranchPseudo and II_ReturnPseudo can probably be removed. I've
preserved the itinerary information for the corresponding pseudo
instructions to avoid making a functional change to these pseudos in
this patch.

Reviewers: vkalintiris

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D12189

llvm-svn: 248273
2015-09-22 13:36:28 +00:00
Daniel Sanders c8cd58fa26 [mips] Correct and improve special-case shuffle instructions.
Summary:
The documentation writes vectors highest-index first whereas LLVM-IR writes
them lowest-index first. As a result, instructions defined in terms of
left_half() and right_half() had the halves reversed.

In addition to correcting them, they have been improved to allow shuffles
that use the same operand twice or in reverse order. For example, ilvev
used to accept masks of the form:
  <0, n, 2, n+2, 4, n+4, ...>
but now accepts:
  <0, 0, 2, 2, 4, 4, ...>
  <n, n, n+2, n+2, n+4, n+4, ...>
  <0, n, 2, n+2, 4, n+4, ...>
  <n, 0, n+2, 2, n+4, 4, ...>

One further improvement is that splati.[bhwd] is now the preferred instruction
for splat-like operations. The other special shuffles are no longer used
for splats. This lead to the discovery that <0, 0, ...> would not cause
splati.[hwd] to be selected and this has also been fixed.

This fixes the enc-3des test from the test-suite on Mips64r6 with MSA.

Reviewers: vkalintiris

Reviewed By: vkalintiris

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9660

llvm-svn: 237689
2015-05-19 12:24:52 +00:00
Daniel Sanders eda60d217b [mips] Generate code for insert/extract operations when using the N64 ABI and MSA.
Summary:
When using the N64 ABI, element-indices use the i64 type instead of i32.
In many cases, we can use iPTR to account for this but additional patterns
and pseudo's are also required.

This fixes most (but not quite all) failures in the test-suite when using
N64 and MSA together.

Reviewers: vkalintiris

Reviewed By: vkalintiris

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9342

llvm-svn: 236494
2015-05-05 10:32:24 +00:00
Toma Tabacu 139644570f [mips] Rename MipsAsmParser functions to conform to the LLVM Coding Standards. No functional changes.
Summary: There are still some functions which should be renamed, but they are inherited from the generic MC classes.

Reviewers: dsanders

Reviewed By: dsanders

Differential Revision: http://reviews.llvm.org/D5068

llvm-svn: 217145
2014-09-04 13:23:44 +00:00
Daniel Sanders 01124a0132 [mips][mips64r6] Add align and dalign
Summary: Depends on D3689

Reviewers: vmedic, zoran.jovanovic, jkolek

Reviewed By: jkolek

Differential Revision: http://reviews.llvm.org/D3728

llvm-svn: 208872
2014-05-15 12:06:36 +00:00
Daniel Sanders e296a0fce5 [mips][msa] Fix vector insertions where the index is variable
Summary:
This isn't supported directly so we rotate the vector by the desired number of
elements, insert to element zero, then rotate back.

The i64 case generates rather poor code on MIPS32. There is an obvious
optimisation to be made in future (do both insert.w's inside a shared 
rotate/unrotate sequence) but for now it's sufficient to select valid code
instead of aborting.

Depends on D3536

Reviewers: matheusalmeida

Reviewed By: matheusalmeida

Differential Revision: http://reviews.llvm.org/D3537

llvm-svn: 207640
2014-04-30 12:09:32 +00:00
Daniel Sanders b3268e71e2 [mips][msa] Fix element extraction where the index is variable.
Summary:
This isn't supported directly so we splat the vector element and extract
the most convenient copy.

Reviewers: matheusalmeida

Reviewed By: matheusalmeida

Differential Revision: http://reviews.llvm.org/D3530

llvm-svn: 207524
2014-04-29 13:31:37 +00:00
Daniel Sanders b50ccf8e26 [mips] Rewrite MipsAsmParser and MipsOperand.
Summary:
Highlights:
- Registers are resolved much later (by the render method).
  Prior to that point, GPR32's/GPR64's are GPR's regardless of register
  size. Similarly FGR32's/FGR64's/AFGR64's are FGR's regardless of register
  size or FR mode. Numeric registers can be anything.
- All registers are parsed the same way everywhere (even when handling
  symbol aliasing)
  - One consequence is that all registers can be specified numerically
    almost anywhere (e.g. $fccX, $wX). The exception is symbol aliasing
    but that can be easily resolved.
- Removes the need for the hasConsumedDollar hack
- Parenthesis and Bracket suffixes are handled generically
- Micromips instructions are parsed directly instead of going through the
  standard encodings first.
- rdhwr accepts all 32 registers, and the following instructions that previously
  xfailed now work:
    ddiv, ddivu, div, divu, cvt.l.[ds], se[bh], wsbh, floor.w.[ds], c.ngl.d,
    c.sf.s, dsbh, dshd, madd.s, msub.s, nmadd.s, nmsub.s, swxc1
- Diagnostics involving registers point at the correct character (the $)
- There's only one kind of immediate in MipsOperand. LSA immediates are handled
  by the predicate and renderer.

Lowlights:
- Hardcoded '$zero' in the div patterns is handled with a hack.
  MipsOperand::isReg() will return true for a k_RegisterIndex token
  with Index == 0 and getReg() will return ZERO for this case. Note that it
  doesn't return ZERO_64 on isGP64() targets.
- I haven't cleaned up all of the now-unused functions.
  Some more of the generic parser could be removed too (integers and relocs
  for example).
- insve.df needed a custom decoder to handle the implicit fourth operand that
  was needed to make it parse correctly. The difficulty was that the matcher
  expected a Token<'0'> but gets an Imm<0>. Adding an implicit zero solved this.

Reviewers: matheusalmeida, vmedic

Reviewed By: matheusalmeida

Differential Revision: http://llvm-reviews.chandlerc.com/D3222

llvm-svn: 205292
2014-04-01 10:35:28 +00:00
Daniel Sanders e34a120285 Revert: [mips] Rewrite MipsAsmParser and MipsOperand.' due to buildbot errors in lld tests.
It's currently unable to parse 'sym + imm' without surrounding parenthesis.

llvm-svn: 205237
2014-03-31 18:51:43 +00:00
Daniel Sanders 0c648ba5be [mips] Rewrite MipsAsmParser and MipsOperand.
Summary:
Highlights:
- Registers are resolved much later (by the render method).
  Prior to that point, GPR32's/GPR64's are GPR's regardless of register
  size. Similarly FGR32's/FGR64's/AFGR64's are FGR's regardless of register
  size or FR mode. Numeric registers can be anything.
- All registers are parsed the same way everywhere (even when handling
  symbol aliasing)
  - One consequence is that all registers can be specified numerically
    almost anywhere (e.g. $fccX, $wX). The exception is symbol aliasing
    but that can be easily resolved.
- Removes the need for the hasConsumedDollar hack
- Parenthesis and Bracket suffixes are handled generically
- Micromips instructions are parsed directly instead of going through the
  standard encodings first.
- rdhwr accepts all 32 registers, and the following instructions that previously
  xfailed now work:
    ddiv, ddivu, div, divu, cvt.l.[ds], se[bh], wsbh, floor.w.[ds], c.ngl.d,
    c.sf.s, dsbh, dshd, madd.s, msub.s, nmadd.s, nmsub.s, swxc1
- Diagnostics involving registers point at the correct character (the $)
- There's only one kind of immediate in MipsOperand. LSA immediates are handled
  by the predicate and renderer.

Lowlights:
- Hardcoded '$zero' in the div patterns is handled with a hack.
  MipsOperand::isReg() will return true for a k_RegisterIndex token
  with Index == 0 and getReg() will return ZERO for this case. Note that it
  doesn't return ZERO_64 on isGP64() targets.
- I haven't cleaned up all of the now-unused functions.
  Some more of the generic parser could be removed too (integers and relocs
  for example).
- insve.df needed a custom decoder to handle the implicit fourth operand that
  was needed to make it parse correctly. The difficulty was that the matcher
  expected a Token<'0'> but gets an Imm<0>. Adding an implicit zero solved this.

Reviewers: matheusalmeida, vmedic

Reviewed By: matheusalmeida

Differential Revision: http://llvm-reviews.chandlerc.com/D3222

llvm-svn: 205229
2014-03-31 17:43:46 +00:00
Daniel Sanders df22154579 [mips] BSEL's and BINS[RL] operands are reversed compared to the vselect node used in the pattern.
Summary:
Correct the match patterns and the lowerings that made the CodeGen tests pass despite the mistakes.

The original testcase that discovered the problem was SingleSource/UnitTests/SignlessType/factor.c in test-suite.
During review, we also found that some of the existing CodeGen tests were incorrect and fixed them:
* bitwise.ll: In bsel_v16i8 the IfSet/IfClear were reversed because bsel and bmnz have different operand orders and the test didn't correctly account for this. bmnz goes 'IfClear, IfSet, CondMask', while bsel goes 'CondMask, IfClear, IfSet'.
* vec.ll: In the cases where a bsel is emitted as a bmnz (they are the same operation with a different input tied to the result) the operands were in the wrong order.
* compare.ll and compare_float.ll: The bsel operand order was correct for a greater-than comparison, but a greater-than comparison instruction doesn't exist. Lowering this operation inverts the condition so the IfSet/IfClear need to be swapped to match.

The differences between BSEL, BMNZ, and BMZ and how they map to/from vselect are rather confusing. I've therefore added a note to MSA.txt to explain this in a single place in addition to the comments that explain each case.

Reviewers: matheusalmeida, jacksprat

Reviewed By: matheusalmeida

Differential Revision: http://llvm-reviews.chandlerc.com/D3028

llvm-svn: 203657
2014-03-12 11:54:00 +00:00
Daniel Sanders fa961d76f0 [mips] Prevent %lo relocation being used on MSA loads and stores.
Summary:
Parts of the compiler still believed MSA load/stores have a 16-bit offset when
it is actually 10-bit. Corrected this, and fixed a closely related issue this
uncovered where load/stores with 10-bit and 12-bit offsets (MSA and microMIPS
respectively) could not load/store using offsets from the stack/frame pointer.
They accepted frameindex+offset, but not frameindex by itself.

Reviewers: jacksprat, matheusalmeida

Reviewed By: jacksprat

Differential Revision: http://llvm-reviews.chandlerc.com/D2888

llvm-svn: 202717
2014-03-03 14:31:21 +00:00
Matheus Almeida 4b27eb588c [mips][msa] Add DLSA instruction.
llvm-svn: 201081
2014-02-10 12:05:17 +00:00
Matheus Almeida 883a2f893d [mips][msa] Make LSA_DESC a parameterizable class.
This way it's possible to share the instruction's description for LSA and
DLSA (to be added).

No functional changes.

llvm-svn: 201078
2014-02-10 11:15:37 +00:00
Matheus Almeida 1ace1f1236 [mips][msa] Add insert.d instruction.
This instruction is only available on Mips64 cores that implement the MSA ASE.

llvm-svn: 200543
2014-01-31 13:31:20 +00:00
Matheus Almeida ec079d9e1d [mips][msa] Add fill.d instruction.
This instruction is only available on Mips64 cores
that implement the MSA ASE.

llvm-svn: 200400
2014-01-29 15:12:02 +00:00
Matheus Almeida 74070327b2 [mips][msa] Add copy_{u,s}.d.
These instructions are only available on Mips64 cores
that implement the MSA ASE.

llvm-svn: 200398
2014-01-29 14:05:28 +00:00
Alp Toker cb40291100 Fix known typos
Sweep the codebase for common typos. Includes some changes to visible function
names that were misspelt.

llvm-svn: 200018
2014-01-24 17:20:08 +00:00
Daniel Sanders b825a634d6 [mips][msa] Correct pattern for LSA
Summary:
$rs and $rt were the wrong way round in the .td and the testcase wasn't
strict enough to detect the mistake.

Reviewers: matheusalmeida

Reviewed By: matheusalmeida

Differential Revision: http://llvm-reviews.chandlerc.com/D2554

llvm-svn: 199498
2014-01-17 15:40:05 +00:00
Daniel Sanders c309be2f1f [mips][msa] Correct sld and sldi builtins.
Summary: The result register of these instructions is also the first operand.

Reviewers: jacksprat, dsanders

Reviewed By: dsanders

Differential Revision: http://llvm-reviews.chandlerc.com/D2362
Differential Revision: http://llvm-reviews.chandlerc.com/D2363

llvm-svn: 196910
2013-12-10 11:37:00 +00:00
Matheus Almeida 6b59c449d9 [mips][msa] Fix issue with immediate fields of LD/ST instructions
not being correctly encoded/decoded.
In more detail, immediate fields of LD/ST instructions should be
divided/multiplied by the size of the data format before encoding and
after decoding, respectively.

llvm-svn: 196494
2013-12-05 11:06:22 +00:00
Daniel Sanders f93e8152c4 [mips][msa] Pseudo instructions require HasMSA too. Inherit from MSAPseudo instead of MipsPseudo
There's no test case for this commit. This is because it is doubtful that the
incorrect behaviour can actually trigger. When MSA is not enabled, the type
legalizer should have eliminated all occurrences of patterns the affected
pseudo-instruction could possibly match before instruction selection occurs.

llvm-svn: 195252
2013-11-20 14:32:28 +00:00
Daniel Sanders 6b97d604ff [mips][msa] Remove unused instruction class MSA_I8_X_DESC_BASE
llvm-svn: 195245
2013-11-20 13:01:10 +00:00
Jack Carter 03af6d1456 long line correction
llvm-svn: 195175
2013-11-20 00:12:44 +00:00
Matheus Almeida 50c6e82222 [mips][msa] Update encoding of bnz.v (typo).
Note that there's no hardware yet that relies on that encoding.

llvm-svn: 195006
2013-11-18 13:09:54 +00:00
Matheus Almeida 779c593708 [mips][msa] Fix immediate value of LSA instruction as it was being wrongly encoded.
The immediate field should be encoded as "imm - 1" as the CPU always adds one to that field.

llvm-svn: 195004
2013-11-18 12:32:49 +00:00