Commit Graph

4412 Commits

Author SHA1 Message Date
Graham Hunter 1a9195d817 [SVE][MVT] Fixed-length vector MVT ranges
* Reordered MVT simple types to group scalable vector types
    together.
  * New range functions in MachineValueType.h to only iterate over
    the fixed-length int/fp vector types.
  * Stopped backends which don't support scalable vector types from
    iterating over scalable types.

Reviewers: sdesmalen, greened

Reviewed By: greened

Differential Revision: https://reviews.llvm.org/D66339

llvm-svn: 372099
2019-09-17 10:19:23 +00:00
Guillaume Chatelet 3620263532 [Alignment] Introduce llvm::Align to MCSection
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet, JDevlieghere

Subscribers: arsenm, sdardis, jvesely, nhaehnle, sbc100, hiraditya, aheejin, jrtc27, atanasyan, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67486

llvm-svn: 371831
2019-09-13 09:29:59 +00:00
Guillaume Chatelet af11cc7eb5 [Alignment] Move OffsetToAlignment to Alignment.h
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet, JDevlieghere, alexshap, rupprecht, jhenderson

Subscribers: sdardis, nemanjai, hiraditya, kbarton, jakehehrlich, jrtc27, MaskRay, atanasyan, jsji, seiya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D67499

llvm-svn: 371742
2019-09-12 15:20:36 +00:00
Petar Avramovic ff6ac1eb5f [MIPS GlobalISel] Select indirect branch
Select G_BRINDIRECT for MIPS32.

Differential Revision: https://reviews.llvm.org/D67441

llvm-svn: 371730
2019-09-12 11:44:36 +00:00
Petar Avramovic 646e1f7b7f [MIPS GlobalISel] Lower G_DYN_STACKALLOC
IRTranslator creates G_DYN_STACKALLOC instruction during expansion of
alloca when argument that tells number of elements to allocate on stack
is a virtual register. Use default lowering for MIPS32.

Differential Revision: https://reviews.llvm.org/D67440

llvm-svn: 371728
2019-09-12 11:39:50 +00:00
Petar Avramovic 75e43a607c [MIPS GlobalISel] Select G_IMPLICIT_DEF
G_IMPLICIT_DEF is used for both integer and floating point implicit-def.
Handle G_IMPLICIT_DEF as ambiguous opcode in MipsRegisterBankInfo.
Select G_IMPLICIT_DEF for MIPS32.

Differential Revision: https://reviews.llvm.org/D67439

llvm-svn: 371727
2019-09-12 11:32:38 +00:00
Guillaume Chatelet 97264366fb [Alignment][NFC] use llvm::Align for AsmPrinter::EmitAlignment
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: dschuff, sdardis, nemanjai, hiraditya, kbarton, jrtc27, MaskRay, atanasyan, jsji, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67443

llvm-svn: 371616
2019-09-11 13:37:35 +00:00
Guillaume Chatelet 48904e9452 [Alignment] Use llvm::Align in MachineFunction and TargetLowering - fixes mir parsing
Summary:
This catches malformed mir files which specify alignment as log2 instead of pow2.
See https://reviews.llvm.org/D65945 for reference,

This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: MatzeB, qcolombet, dschuff, arsenm, sdardis, nemanjai, jvesely, nhaehnle, hiraditya, kbarton, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, Petar.Avramovic, asbirlea, s.egerton, pzheng, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67433

llvm-svn: 371608
2019-09-11 11:16:48 +00:00
Simon Atanasyan d811d9115b [mips][msa] Fix infinite loop for mips.nori.b intrinsic
When value of immediate in `mips.nori.b` is 255 (which has all ones in
binary form as 8bit integer) DAGCombiner and Legalizer would fall in an
infinite loop. DAGCombiner would try to simplify `or %value, -1` by
turning `%value` into UNDEF. Legalizer will turn it back into `Constant<0>`
which would then be again turned into UNDEF by DAGCombiner. To avoid this
loop we make UNDEF legal for MSA int types on Mips.

Patch by Mirko Brkusanin.

Differential Revision: https://reviews.llvm.org/D67280

llvm-svn: 371607
2019-09-11 11:16:06 +00:00
Guillaume Chatelet b6722af068 [Alignment] Use Align for TargetLowering::MinStackArgumentAlignment
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: sdardis, nemanjai, hiraditya, kbarton, jrtc27, MaskRay, atanasyan, jsji, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67288

llvm-svn: 371498
2019-09-10 09:01:18 +00:00
Simon Atanasyan 56e4ea2bff [mips] Fix decoding of microMIPS JALX instruction
microMIPS jump and link exchange instruction stores a target in a
26-bits field. Despite other microMIPS JAL instructions these bits
are target address shifted right 2 bits [1]. The patch fixes the
JALX instruction decoding and uses 2-bit shift.

[1] MIPS Architecture for Programmers Volume II-B: The microMIPS32 Instruction Set

Differential Revision: https://reviews.llvm.org/D67320

llvm-svn: 371428
2019-09-09 17:28:45 +00:00
Guillaume Chatelet 4fc3ad9e13 [Alignment][NFC] Use Align with TargetLowering::setMinFunctionAlignment
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: jyknight, sdardis, nemanjai, javed.absar, hiraditya, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, s.egerton, pzheng, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67229

llvm-svn: 371200
2019-09-06 12:48:34 +00:00
Petar Avramovic a4bfc8dfda [MIPS GlobalISel] Select G_FENCE
G_FENCE comes form fence instruction. For MIPS fence is generated in
AtomicExpandPass when atomic instruction gets surrounded with fence
instruction when needed.
G_FENCE arguments don't have LLT, because of that there is no job for
legalizer and regbankselect. Instruction select G_FENCE for MIPS32.

Differential Revision: https://reviews.llvm.org/D67181

llvm-svn: 371056
2019-09-05 11:20:32 +00:00
Petar Avramovic f5c7fe0795 [MIPS GlobalISel] Select llvm.trap intrinsic
Select G_INTRINSIC_W_SIDE_EFFECTS for Intrinsic::trap for MIPS32
via legalizeIntrinsic.

Differential Revision: https://reviews.llvm.org/D67180

llvm-svn: 371055
2019-09-05 11:16:37 +00:00
Petar Avramovic d2574d79b6 [MIPS GlobalISel] Lower SRet pointer arguments
Instead of returning structure by value clang usually adds pointer
to that structure as an argument. Pointers don't require special
handling no matter the SRet flag. Remove unsuccessful exit from
lowerCall for arguments with SRet flag if they are pointers.

Differential Revision: https://reviews.llvm.org/D67179

llvm-svn: 371054
2019-09-05 11:12:01 +00:00
Guillaume Chatelet aff45e4b23 [LLVM][Alignment] Make functions using log of alignment explicit
Summary:
This patch renames functions that takes or returns alignment as log2, this patch will help with the transition to llvm::Align.
The renaming makes it explicit that we deal with log(alignment) instead of a power of two alignment.
A few renames uncovered dubious assignments:

 - `MirParser`/`MirPrinter` was expecting powers of two but `MachineFunction` and `MachineBasicBlock` were using deal with log2(align). This patch fixes it and updates the documentation.
 - `MachineBlockPlacement` exposes two flags (`align-all-blocks` and `align-all-nofallthru-blocks`) supposedly interpreted as power of two alignments, internally these values are interpreted as log2(align). This patch updates the documentation,
 - `MachineFunctionexposes` exposes `align-all-functions` also interpreted as power of two alignment, internally this value is interpreted as log2(align). This patch updates the documentation,

Reviewers: lattner, thegameg, courbet

Subscribers: dschuff, arsenm, jyknight, dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, javed.absar, hiraditya, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, dexonsmith, PkmX, jocewei, jsji, Jim, s.egerton, llvm-commits, courbet

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65945

llvm-svn: 371045
2019-09-05 10:00:22 +00:00
Amara Emerson fbaf425b79 [GlobalISel][CallLowering] Add support for splitting types according to calling conventions.
On AArch64, s128 types have to be split into s64 GPRs when passed as arguments.
This change adds the generic support in call lowering for dealing with multiple
registers, for incoming and outgoing args.

Support for splitting for return types not yet implemented.

Differential Revision: https://reviews.llvm.org/D66180

llvm-svn: 370822
2019-09-03 21:42:28 +00:00
Simon Atanasyan 25d5b54542 [mips] Switch to the `.text` section after emitting asm file preamble
Now the last `.section` directive in the MIPS asm file preamble
is the `.section .mdebug.abi`. If assembler code injected for example
by the LLVM `module asm` or the C ` __asm` directives do not contain
explicit switching to the `.text` section it goes to the `.mdebug.abi`
section. It might be unexpected to the user and in fact for example
breaks building some existing code like FreeBSD libc [1].

The patch forces switching to the `.text` section after emitting MIPS
assembler file preamble.

[1] https://bugs.llvm.org/show_bug.cgi?id=43119

Fix PR43119.

Differential Revision: https://reviews.llvm.org/D67014

llvm-svn: 370735
2019-09-03 10:24:07 +00:00
Petar Avramovic e96892a8aa [MIPS GlobalISel] Lower uitofp
Add custom lowering for G_UITOFP for MIPS32.

Differential Revision: https://reviews.llvm.org/D66930

llvm-svn: 370432
2019-08-30 05:51:12 +00:00
Petar Avramovic 6412b56513 [MIPS GlobalISel] Lower fptoui
Add lower for G_FPTOUI. Algorithm is similar to the SDAG version
in TargetLowering::expandFP_TO_UINT.
Lower G_FPTOUI for MIPS32.

Differential Revision: https://reviews.llvm.org/D66929

llvm-svn: 370431
2019-08-30 05:44:02 +00:00
Simon Atanasyan b23857c149 [mips] Inline emitStoreWithSymOffset and emitLoadWithSymOffset methods. NFC
Both methods `MipsTargetStreamer::emitStoreWithSymOffset` and
`MipsTargetStreamer::emitLoadWithSymOffset` are almost the same and
differ argument names only. These methods are used in the single place
so it's better to inline their code and remove original methods.

llvm-svn: 370354
2019-08-29 13:19:50 +00:00
Simon Atanasyan 3464b91ef7 [mips] Fix expanding `lw/sw $reg1, symbol($reg2)` instruction
When a "base" in the `lw/sw $reg1, symbol($reg2)` instruction is
a register and generated code is position independent, backend
does not add the "base" value to the symbol address.
```
lw     $reg1, %got(symbol)($gp)
lw/sw  $reg1, 0($reg1)
```

This patch fixes the bug and adds the missed `addu` instruction by
passing `BaseReg` into the `loadAndAddSymbolAddress` routine and handles
the case when the `BaseReg` is the zero register to escape redundant
`move reg, reg` instruction:
```
lw     $reg1, %got(symbol)($gp)
addu   $reg1, $reg1, $reg2
lw/sw  $reg1, 0($reg1)
```

Differential Revision: https://reviews.llvm.org/D66894

llvm-svn: 370353
2019-08-29 13:19:38 +00:00
Simon Atanasyan 027f1da010 [mips] Add an empty line to separate different patterns. NFC
llvm-svn: 370269
2019-08-28 22:32:16 +00:00
Simon Atanasyan 59bb3609fa [mips] Fix 64-bit address loading in case of applying 32-bit mask to the result
If result of 64-bit address loading combines with 32-bit mask, LLVM
tries to optimize the code and remove "redundant" loading of upper
32-bits of the address. It leads to incorrect code on MIPS64 targets.

MIPS backend creates the following chain of commands to load 64-bit
address in the `MipsTargetLowering::getAddrNonPICSym64` method:
```
(add (shl (add (shl (add %highest(sym), %higher(sym)),
                    16),
               %hi(sym)),
          16),
     %lo(%sym))
```

If the mask presents, LLVM decides to optimize the chain of commands. It
really does not make sense to load upper 32-bits because the 0x0fffffff
mask anyway clears them. After removing redundant commands we get this
chain:
```
(add (shl (%hi(sym), 16), %lo(%sym))
```

There is no patterns matched `(MipsHi (i64 symbol))`. Due a bug in `SYM_32`
predicate definition, backend incorrectly selects a pattern for a 32-bit
symbols and uses the `lui` instruction for loading `%hi(sym)`.

As a result we get incorrect set of instructions with unnecessary 16-bit
left shifting:
```
lui     at,0x0
    R_MIPS_HI16     foo
dsll    at,at,0x10
daddiu  at,at,0
    R_MIPS_LO16     foo
```

This patch resolves two problems:
- Fix `SYM_32/SYM_64` predicates to prevent selection of patterns dedicated
  to 32-bit symbols in case of using N64 ABI.
- Add missed patterns for 64-bit symbols for `%hi/%lo`.

Fix PR42736.

Differential Revision: https://reviews.llvm.org/D66228

llvm-svn: 370268
2019-08-28 22:32:10 +00:00
Simon Atanasyan f46ba4f077 [mips] Use less registers to load address of TargetExternalSymbol
There is no pattern matched `add hi, (MipsLo texternalsym)`. As a result,
loading an address of 32-bit symbol requires two registers and one more
additional instruction:
```
addiu $1, $zero, %lo(foo)
lui   $2, %hi(foo)
addu  $25, $2, $1
```

This patch adds the missed pattern and enables generation more effective
set of instructions:
```
lui   $1, %hi(foo)
addiu $25, $1, %lo(foo)
```

Differential Revision: https://reviews.llvm.org/D66771

llvm-svn: 370196
2019-08-28 12:35:53 +00:00
Petar Avramovic 4a2a653288 [MIPS GlobalISel] ClampScalar G_SHL, G_ASHR and G_LSHR
ClampScalar G_SHL, G_ASHR and G_LSHR to s32 for MIPS32.

Differential Revision: https://reviews.llvm.org/D66533

llvm-svn: 370067
2019-08-27 14:41:44 +00:00
Simon Atanasyan d5918edf0d [mips] Fix indentation. NFC
llvm-svn: 369983
2019-08-26 22:40:34 +00:00
Simon Atanasyan ac64924a55 [mips] clang-format the code. NFC
llvm-svn: 369982
2019-08-26 22:40:28 +00:00
Simon Atanasyan 5f7d6ac7bf [mips] Reduce number of instructions used for loading a global symbol's value
Now `lw/sw $reg, sym+offset` pseudo instructions for global symbol `sym`
are lowering into the following three instructions.
```
lw     $reg, %got(symbol)($gp)
addiu  $reg, $reg, offset
lw/sw  $reg, 0($reg)
```

It's possible to reduce the number of instructions by taking the offset
in account in the final `lw/sw` command. This patch implements that
optimization.
```
lw     $reg, %got(symbol)($gp)
lw/sw  $reg, offset($reg)
```

Differential Revision: https://reviews.llvm.org/D66553

llvm-svn: 369756
2019-08-23 13:36:24 +00:00
Simon Atanasyan 58492b1895 [mips] Do not include offset into `%got` expression for global symbols
Now pseudo instruction `la $6, symbol+8($6)` is expanding into the following
chain of commands:
```
lw    $1, %got(symbol+8)($gp)
addiu $1, $1, 8
addu  $6, $1, $6
```

This is incorrect. When a linker handles the `R_MIPS_GOT16` relocation,
it does not expect to get any addend and breaks on assertion. Otherwise
it has to create new GOT entry for each unique "sym + offset" pair.
Offset for a global symbol should be added to result of loading GOT
entry by a separate `add` command.

The patch fixes the problem by stripping off an offset from the expression
passed to the `%got`. That's interesting that even current code inserts
a separate `add` command.

Differential Revision: https://reviews.llvm.org/D66552

llvm-svn: 369755
2019-08-23 13:36:14 +00:00
Sam Clegg 90b6bb75e8 [MC] Minor cleanup to MCFixup::Kind handling. NFC.
Prefer `MCFixupKind` where possible and add getTargetKind() to
convert to `unsigned` when needed rather than scattering cast
operators around the place.

Differential Revision: https://reviews.llvm.org/D59890

llvm-svn: 369720
2019-08-23 01:00:55 +00:00
Simon Atanasyan 159f621c5c [mips] Replace call `expandLoadAddress` by `loadAndAddSymbolAddress`. NFC
In case of expanding `lw/sw $reg, symbol($reg)` instruction for PIC it's
enough to call the `loadAndAddSymbolAddress` method. Additional work
performed by the `expandLoadAddress` is not required here.

llvm-svn: 369563
2019-08-21 18:54:51 +00:00
Simon Atanasyan bb2f857247 [mips] Remove duplicated case from the `StringSwitch`. NFC
llvm-svn: 369562
2019-08-21 18:54:41 +00:00
Petar Avramovic 7f581df649 [MIPS GlobalISel] NarrowScalar G_ZEXTLOAD and G_SEXTLOAD
NarrowScalar G_ZEXTLOAD and G_SEXTLOAD to s32 for MIPS32.

Differential Revision: https://reviews.llvm.org/D66205

llvm-svn: 369512
2019-08-21 09:43:20 +00:00
Petar Avramovic e406aa791c [MIPS GlobalISel] NarrowScalar G_ZEXT and G_SEXT
NarrowScalar G_ZEXT and G_SEXT to s32 for MIPS32.

Differential Revision: https://reviews.llvm.org/D66204

llvm-svn: 369511
2019-08-21 09:35:02 +00:00
Petar Avramovic 61bf2675b9 [MIPS GlobalISel] Consider type1 when legalizing shifts after r351882
r351882 allows different type for shift amount then result and value
being shifted. Fix MIPS Legalizer rules to take r351882 into account.

Differential Revision: https://reviews.llvm.org/D66203

llvm-svn: 369510
2019-08-21 09:31:29 +00:00
Petar Avramovic 5b4c5c2c54 [MIPS GlobalISel] NarrowScalar G_TRUNC
Add NarrowScalar for G_TRUNC when NarrowTy is half the size of source.
NarrowScalar G_TRUNC to s32 for MIPS32.

Differential Revision: https://reviews.llvm.org/D66202

llvm-svn: 369509
2019-08-21 09:26:39 +00:00
Daniel Sanders 0c47611131 Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM
Summary:
This clang-tidy check is looking for unsigned integer variables whose initializer
starts with an implicit cast from llvm::Register and changes the type of the
variable to llvm::Register (dropping the llvm:: where possible).

Partial reverts in:
X86FrameLowering.cpp - Some functions return unsigned and arguably should be MCRegister
X86FixupLEAs.cpp - Some functions return unsigned and arguably should be MCRegister
X86FrameLowering.cpp - Some functions return unsigned and arguably should be MCRegister
HexagonBitSimplify.cpp - Function takes BitTracker::RegisterRef which appears to be unsigned&
MachineVerifier.cpp - Ambiguous operator==() given MCRegister and const Register
PPCFastISel.cpp - No Register::operator-=()
PeepholeOptimizer.cpp - TargetInstrInfo::optimizeLoadInstr() takes an unsigned&
MachineTraceMetrics.cpp - MachineTraceMetrics lacks a suitable constructor

Manual fixups in:
ARMFastISel.cpp - ARMEmitLoad() now takes a Register& instead of unsigned&
HexagonSplitDouble.cpp - Ternary operator was ambiguous between unsigned/Register
HexagonConstExtenders.cpp - Has a local class named Register, used llvm::Register instead of Register.
PPCFastISel.cpp - PPCEmitLoad() now takes a Register& instead of unsigned&

Depends on D65919

Reviewers: arsenm, bogner, craig.topper, RKSimon

Reviewed By: arsenm

Subscribers: RKSimon, craig.topper, lenary, aemerson, wuzish, jholewinski, MatzeB, qcolombet, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, wdng, nhaehnle, sbc100, jgravelle-google, kristof.beyls, hiraditya, aheejin, kbarton, fedor.sergeev, javed.absar, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, tpr, PkmX, jocewei, jsji, Petar.Avramovic, asbirlea, Jim, s.egerton, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65962

llvm-svn: 369041
2019-08-15 19:22:08 +00:00
Jonas Devlieghere 0eaee545ee [llvm] Migrate llvm::make_unique to std::make_unique
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.

llvm-svn: 369013
2019-08-15 15:54:37 +00:00
Amara Emerson e14c91b71a [GlobalISel] Make the InstructionSelector instance non-const, allowing state to be maintained.
Currently we can't keep any state in the selector object that we get from
subtarget. As a result we have to plumb through all our variables through
multiple functions. This change makes it non-const and adds a virtual init()
method to allow further state to be captured for each target.

AArch64 makes use of this in this patch to cache a call to hasFnAttribute()
which is expensive to call, and is used on each selection of G_BRCOND.

Differential Revision: https://reviews.llvm.org/D65984

llvm-svn: 368652
2019-08-13 06:26:59 +00:00
Daniel Sanders e9a57c2b23 [globalisel] Add G_SEXT_INREG
Summary:
Targets often have instructions that can sign-extend certain cases faster
than the equivalent shift-left/arithmetic-shift-right. Such cases can be
identified by matching a shift-left/shift-right pair but there are some
issues with this in the context of combines. For example, suppose you can
sign-extend 8-bit up to 32-bit with a target extend instruction.
  %1:_(s32) = G_SHL %0:_(s32), i32 24 # (I've inlined the G_CONSTANT for brevity)
  %2:_(s32) = G_ASHR %1:_(s32), i32 24
  %3:_(s32) = G_ASHR %2:_(s32), i32 1
would reasonably combine to:
  %1:_(s32) = G_SHL %0:_(s32), i32 24
  %2:_(s32) = G_ASHR %1:_(s32), i32 25
which no longer matches the special case. If your shifts and extend are
equal cost, this would break even as a pair of shifts but if your shift is
more expensive than the extend then it's cheaper as:
  %2:_(s32) = G_SEXT_INREG %0:_(s32), i32 8
  %3:_(s32) = G_ASHR %2:_(s32), i32 1
It's possible to match the shift-pair in ISel and emit an extend and ashr.
However, this is far from the only way to break this shift pair and make
it hard to match the extends. Another example is that with the right
known-zeros, this:
  %1:_(s32) = G_SHL %0:_(s32), i32 24
  %2:_(s32) = G_ASHR %1:_(s32), i32 24
  %3:_(s32) = G_MUL %2:_(s32), i32 2
can become:
  %1:_(s32) = G_SHL %0:_(s32), i32 24
  %2:_(s32) = G_ASHR %1:_(s32), i32 23

All upstream targets have been configured to lower it to the current
G_SHL,G_ASHR pair but will likely want to make it legal in some cases to
handle their faster cases.

To follow-up: Provide a way to legalize based on the constant. At the
moment, I'm thinking that the best way to achieve this is to provide the
MI in LegalityQuery but that opens the door to breaking core principles
of the legalizer (legality is not context sensitive). That said, it's
worth noting that looking at other instructions and acting on that
information doesn't violate this principle in itself. It's only a
violation if, at the end of legalization, a pass that checks legality
without being able to see the context would say an instruction might not be
legal. That's a fairly subtle distinction so to give a concrete example,
saying %2 in:
  %1 = G_CONSTANT 16
  %2 = G_SEXT_INREG %0, %1
is legal is in violation of that principle if the legality of %2 depends
on %1 being constant and/or being 16. However, legalizing to either:
  %2 = G_SEXT_INREG %0, 16
or:
  %1 = G_CONSTANT 16
  %2:_(s32) = G_SHL %0, %1
  %3:_(s32) = G_ASHR %2, %1
depending on whether %1 is constant and 16 does not violate that principle
since both outputs are genuinely legal.

Reviewers: bogner, aditya_nandakumar, volkan, aemerson, paquette, arsenm

Subscribers: sdardis, jvesely, wdng, nhaehnle, rovka, kristof.beyls, javed.absar, hiraditya, jrtc27, atanasyan, Petar.Avramovic, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61289

llvm-svn: 368487
2019-08-09 21:11:20 +00:00
Simon Atanasyan 242c5a70d4 [Mips][Codegen] Fix fast-isel mixing of FGR64 and AFGR64 registers
Fast-isel was picking AFGR64 register class for processing call
arguments when +fp64 options was used. We simply check is option +fp64
is used and pick appropriate register.

Patch by Mirko Brkusanin.

Differential Revision: https://reviews.llvm.org/D65886

llvm-svn: 368433
2019-08-09 12:02:32 +00:00
Tim Northover e1a5f668b3 GlobalISel: pack various parameters for lowerCall into a struct.
I've now needed to add an extra parameter to this call twice recently. Not only
is the signature getting extremely unwieldy, but just updating all of the
callsites and implementations is a pain. Putting the parameters in a struct
sidesteps both issues.

llvm-svn: 368408
2019-08-09 08:26:38 +00:00
Petar Avramovic caef930699 [MIPS GlobalISel] Select jump_table and brjt
G_JUMP_TABLE and G_BRJT appear from translation of switch statement.
Select these two instructions for MIPS32, both pic and non-pic.

Differential Revision: https://reviews.llvm.org/D65861

llvm-svn: 368274
2019-08-08 10:21:12 +00:00
Simon Atanasyan e5fa049efa [mips] Make a couple of class methods plain static functions. NFC
llvm-svn: 368162
2019-08-07 12:21:41 +00:00
Simon Atanasyan 8a7c0e7c0a [mips] Use isMicroMips() function to check enabled feature flag. NFC
llvm-svn: 368161
2019-08-07 12:21:32 +00:00
Simon Atanasyan 9f2e076f27 [Mips] Instruction `sc` now accepts symbol as an argument
Function MipsAsmParser::expandMemInst() did not properly handle
instruction `sc` with a symbol as an argument because first argument
would be counted twice. We add additional checks and handle this case
separately.

Patch by Mirko Brkusanin.

Differential Revision: https://reviews.llvm.org/D64252

llvm-svn: 368160
2019-08-07 12:21:26 +00:00
Tim Northover 522fb7eedc GlobalISel: support swiftself attribute
llvm-svn: 367683
2019-08-02 14:09:49 +00:00
Daniel Sanders 2bea69bf65 Finish moving TargetRegisterInfo::isVirtualRegister() and friends to llvm::Register as started by r367614. NFC
llvm-svn: 367633
2019-08-01 23:27:28 +00:00
Simon Atanasyan 0620cf11ec [mips] Fix lowering load/store instruction in PIC case
If an operand of the `lw/sw` instructions is a symbol, these instructions
incorrectly lowered using not-position-independent chain of commands.
For PIC code we should use `lw/addiu` instructions with the `R_MIPS_GOT16`
and `R_MIPS_LO16` relocations respectively. Instead of that LLVM generates
position dependent code with the `R_MIPS_HI16` and `R_MIPS_LO16`
relocations.

This patch provides a fix for the bug by handling PIC case separately in
the `MipsAsmParser::expandMemInst`. The main idea is to generate a chain
of PIC instructions to load a symbol address into a register and then
load the address content.

The fix is not optimal and does not fix all PIC-related problems. This
is a task for subsequent patches.

Differential Revision: https://reviews.llvm.org/D65524

llvm-svn: 367580
2019-08-01 16:04:29 +00:00