Commit Graph

7338 Commits

Author SHA1 Message Date
Dmitry Preobrazhensky 434d59250e [AMDGPU][MC][GFX10][WS32] Corrected decoding of dst operand for v_cmp_*_sdwa opcodes
See bug 43484: https://bugs.llvm.org/show_bug.cgi?id=43484

Reviewers: arsenm, rampitec

Differential Revision: https://reviews.llvm.org/D68349

llvm-svn: 373745
2019-10-04 13:04:17 +00:00
Dmitry Preobrazhensky 9bd763679f [AMDGPU][MC][GFX10] Enabled decoding of 'null' operand
See bug 43485: https://bugs.llvm.org/show_bug.cgi?id=43485

Reviewers: arsenm, rampitec

Differential Revision: https://reviews.llvm.org/D68348

llvm-svn: 373740
2019-10-04 12:38:36 +00:00
Dmitry Preobrazhensky 94d040706d [AMDGPU][MC][GFX10] Corrected definition of FLAT GLOBAL/SCRATCH instructions
See bug 43483: https://bugs.llvm.org/show_bug.cgi?id=43483

Reviewers: arsenm, rampitec

Differential Revision: https://reviews.llvm.org/D68347

llvm-svn: 373736
2019-10-04 12:10:22 +00:00
Jordan Rupprecht 9d4a6b1bb2 [llvm-objdump] Further rearrange llvm-objdump sections for compatability
Summary:
rL371826 rearranged some output from llvm-objdump for GNU objdump compatability, but there still seem to be some more.

I think this rearrangement is a little closer. Overview of the ordering which matches GNU objdump:
* Archive headers
* File headers
* Section headers
* Symbol table
* Dwarf debugging
* Relocations (if `--disassemble` is not used)
* Section contents
* Disassembly

Reviewers: jhenderson, justice_adams, grimar, ychen, espindola

Reviewed By: jhenderson

Subscribers: aprantl, emaste, arichardson, jrtc27, atanasyan, seiya, llvm-commits, MaskRay

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68066

llvm-svn: 373671
2019-10-03 22:01:08 +00:00
Nick Desaulniers ede784ff5a [AArch64InstPrinter] prefer bfi to bfc for < armv8.2-a
Summary:
Fixes pr/42576.

Link: https://github.com/ClangBuiltLinux/linux/issues/697

Reviewers: t.p.northover

Reviewed By: t.p.northover

Subscribers: kristof.beyls, hiraditya, llvm-commits, srhines

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68356

llvm-svn: 373655
2019-10-03 20:10:02 +00:00
Edward Jones f5177a7db4 [RISCV] Add obsolete aliases of fscsr, frcsr (fssr, frsr)
These old aliases were renamed, but are still used by some projects (eg newlib).

Differential Revision: https://reviews.llvm.org/D68392

llvm-svn: 373618
2019-10-03 15:47:28 +00:00
Simon Atanasyan f6551ddfce [mips] Push `fixup_Mips_LO16` fixup for `jialc` and `jic` instructions
llvm-svn: 373591
2019-10-03 12:08:26 +00:00
Simon Atanasyan afe7197f13 [mips] Use llvm-readobj `-A` flag in test cases. NFC
llvm-svn: 373589
2019-10-03 12:08:04 +00:00
Nico Weber 2331cd69cd Revert "[MC] Emit unused undefined symbol even if its binding is not set"
This reverts r373168. It caused PR43511.

llvm-svn: 373242
2019-09-30 18:13:48 +00:00
Fangrui Song 34f9e98aae [test] Change llvm-readobj --arm-attributes to --arch-specific after r373125
llvm-svn: 373179
2019-09-30 04:45:14 +00:00
Fangrui Song c513360662 [MC] Emit unused undefined symbol even if its binding is not set
For the following two cases, we currently suppress the symbols. This
patch emits them (compatible with GNU as).

* `test2_a = undef`: if `undef` is otherwise unused.
* `.hidden hidden`: if `hidden` is unused. This is the main point of the
  patch, because omitting the symbol would cause a linker semantic
  difference.

It causes a behavior change that is not compatible with GNU as:

.weakref foo1, bar1

When neither foo1 nor bar1 is used, we now emit bar1, which is arguably
more consistent.

Another change is that we will emit .TOC. for .TOC.@tocbase .  For this
directive, suppressing .TOC. can be seen as a size optimization, but we
choose to drop it for simplicity and consistency.

llvm-svn: 373168
2019-09-29 15:26:12 +00:00
Dmitry Preobrazhensky 436d5b335a [AMDGPU][MC] Corrected parsing of registers
Summary of changes:

refactored code for better readability and future improvements;
fixed bug 41281: https://bugs.llvm.org/show_bug.cgi?id=41281

Reviewers: artem.tamazov, arsenm

Differential Revision: https://reviews.llvm.org/D65224

llvm-svn: 373094
2019-09-27 15:41:31 +00:00
Alexandros Lamprineas c006b6f4cb [MC][ARM] vscclrm disassembles as vldmia
Happens only when the mve.fp subtarget feature is enabled:

$ llvm-mc -triple thumbv8.1m.main -mattr=+mve.fp,+8msecext -disassemble <<< "0x9f,0xec,0x08,0x0b"
  .text
  vldmia  pc, {d0, d1, d2, d3}
$ llvm-mc -triple thumbv8.1m.main -mattr=+8msecext -disassemble <<< "0x9f,0xec,0x08,0x0b"
  .text
  vscclrm {d0, d1, d2, d3, vpr}

Assembling returns the correct encoding with or without mve.fp:

$ llvm-mc -triple thumbv8.1m.main -mattr=+mve.fp,+8msecext -show-encoding <<< "vscclrm {d0-d3, vpr}"
  .text
  vscclrm {d0, d1, d2, d3, vpr}   @ encoding: [0x9f,0xec,0x08,0x0b]
$ llvm-mc -triple thumbv8.1m.main -mattr=+8msecext -show-encoding <<< "vscclrm {d0-d3, vpr}"
  .text
  vscclrm {d0, d1, d2, d3, vpr}   @ encoding: [0x9f,0xec,0x08,0x0b]

The problem seems to be in the TableGen description of VSCCLRMD.
The least significant bit should be set to zero.

Differential Revision: https://reviews.llvm.org/D68025

llvm-svn: 373052
2019-09-27 08:22:24 +00:00
Thomas Lively 3fcdd25ad5 [WebAssembly] v128.andnot
Summary:
As specified at
https://github.com/WebAssembly/simd/blob/master/proposals/simd/SIMD.md#bitwise-and-not

Reviewers: aheejin

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68113

llvm-svn: 373041
2019-09-27 02:11:40 +00:00
Thomas Lively 81125f7362 [WebAssembly] SIMD Load and extend operations
Summary:
As specified at
https://github.com/webassembly/simd/blob/master/proposals/simd/SIMD.md#load-and-extend.
These instructions are behind the unimplemented-simd128 target feature
for now because they have not been implemented in V8 yet.

Reviewers: aheejin

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68058

llvm-svn: 373040
2019-09-27 02:06:50 +00:00
Sam Clegg 079cba04bf [MC][WebAssembly] Error on data symbols in the text section.
Previously we had an assert but this can actually occur in valid user
code so we need to handle this in release builds too.

Differential Revision: https://reviews.llvm.org/D67997

llvm-svn: 372934
2019-09-25 23:33:16 +00:00
Thomas Lively 99d3dd287a [WebAssembly] vNxM.load_splat instructions
Summary:
Adds the new load_splat instructions as specified at
https://github.com/WebAssembly/simd/blob/master/proposals/simd/SIMD.md#load-and-splat.

DAGISel does not allow matching multiple copies of the same load in a
single pattern, so we use a new node in WebAssemblyISD to wrap loads
that should be splatted.

Depends on D67783.

Reviewers: aheejin

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67784

llvm-svn: 372655
2019-09-23 20:42:12 +00:00
Dmitry Preobrazhensky 6784a3cd79 [AMDGPU][MC] Corrected handling of relocatable expressions
See bug 43359: https://bugs.llvm.org//show_bug.cgi?id=43359

Reviewers: rampitec

Differential Revision: https://reviews.llvm.org/D67829

llvm-svn: 372622
2019-09-23 15:41:51 +00:00
Ulrich Weigand 819c1651f7 [SystemZ] Support z15 processor name
The recently announced IBM z15 processor implements the architecture
already supported as "arch13" in LLVM.  This patch adds support for
"z15" as an alternate architecture name for arch13.

The patch also uses z15 in a number of places where we used arch13
as long as the official name was not yet announced.

llvm-svn: 372435
2019-09-20 23:04:45 +00:00
Simon Atanasyan 164dbd386d [mips] Expand 'lw/sw' instructions for 32-bit GOT
In case of using 32-bit GOT access to the table requires two instructions
with attached %got_hi and %got_lo relocations. This patch implements
correct expansion of 'lw/sw' instructions in that case.

Differential Revision: https://reviews.llvm.org/D67705

llvm-svn: 372251
2019-09-18 19:19:47 +00:00
Simon Atanasyan 1ebdbad475 [mips] Mark tests for lw/sw expansion in PIC by a separate "check prefix". NFC
That simplify adding XGOT tests later.

llvm-svn: 372219
2019-09-18 12:24:30 +00:00
Eli Friedman ddf5e86c22 [ARM] VFPv2 only supports 16 D registers.
r361845 changed the way we handle "D16" vs. "D32" targets; there used to
be a negative "d16" which removed instructions from the instruction set,
and now there's a "d32" feature which adds instructions to the
instruction set.  This is good, but there was an oversight in the
implementation: the behavior of VFPv2 was changed.  In particular, the
"vfp2" feature was changed to imply "d32". This is wrong: VFPv2 only
supports 16 D registers.

In practice, this means if you specify -mfpu=vfpv2, the compiler will
generate illegal instructions.

This patch gets rid of "vfp2d16" and "vfp2d16sp", and fixes "vfp2" and
"vfp2sp" so they don't imply "d32".

Differential Revision: https://reviews.llvm.org/D67375

llvm-svn: 372186
2019-09-17 21:42:38 +00:00
Thomas Lively ae530c5c80 [WebAssembly] Narrowing and widening SIMD ops
Summary:
Implements target-specific LLVM intrinsics and clang builtins for
these new SIMD operations, as described at https://github.com/WebAssembly/simd/blob/master/proposals/simd/SIMD.md#integer-to-integer-narrowing.

Reviewers: aheejin

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D67425

llvm-svn: 371906
2019-09-13 22:54:41 +00:00
Tim Northover f1c2892912 AArch64: support arm64_32, an ILP32 slice for watchOS.
This is the main CodeGen patch to support the arm64_32 watchOS ABI in LLVM.
FastISel is mostly disabled for now since it would generate incorrect code for
ILP32.

llvm-svn: 371722
2019-09-12 10:22:23 +00:00
Sam Elliott d57de491be [RISCV] Support llvm-objdump -M no-aliases and -M numeric
Summary:
Now that llvm-objdump allows target-specific options, we match the
`no-aliases` and `numeric` options for RISC-V, as supported by GNU objdump.

This is done by overriding the variables used for the command-line options, so
that the command-line options are still supported.

This patch updates all tests using `llvm-objdump -riscv-no-aliases` to use
`llvm-objdump -M no-aliases`.

Reviewers: luismarques, asb

Reviewed By: luismarques, asb

Subscribers: pzheng, hiraditya, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, kito-cheng, shiva0217, jrtc27, MaskRay, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, psnobl, benna, Jim, s.egerton, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66139

llvm-svn: 371534
2019-09-10 16:24:03 +00:00
Sam Elliott 6b877f6aac [RISCV] Add Option for Printing Architectural Register Names
Summary:
This is an option primarily to use during testing. Instead of always
printing registers using their ABI names, this allows a user to request they
are printed with their architectural name.

This is then used in the register constraint tests to ensure the mapping
between architectural and abi names is correct.

Reviewers: asb, luismarques

Reviewed By: asb

Subscribers: pzheng, hiraditya, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, kito-cheng, shiva0217, jrtc27, MaskRay, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, psnobl, benna, Jim, s.egerton, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65950

llvm-svn: 371531
2019-09-10 15:55:55 +00:00
Reid Kleckner 87d47cb7c4 Remove some unnecessary REQUIRES: shell lines
This means these tests will run on Windows. Replace one with
UNSUPPORTED: system-windows.

llvm-svn: 371473
2019-09-10 00:06:52 +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
Simon Tatham 0e48bd24e2 [ARM] Remove some spurious MVE reduction instructions.
The family of 'dual-accumulating' vector multiply-add instructions
(VMLADAV, VMLALDAV and VRMLALDAVH) can all operate on both signed and
unsigned integer types, and they all have an 'exchange' variant (with
an X in the name) that modifies which pairs of vector lanes in the two
inputs are multiplied together. But there's a clause in the spec that
says that the X variants //don't// operate on unsigned integer types,
only signed. You can have X, or unsigned, or neither, but not both.

We didn't notice that clause when we implemented the MC support for
these instructions, so LLVM believes that things like VMLADAVX.U8 do
exist, contradicting the spec. Here I fix that by conditioning them
out in Tablegen.

In order to do that, I've reversed the nesting order of the Tablegen
multiclasses for those instructions. Previously, the innermost
multiclass generated the X and not-X variants, and the one outside
that generated the A and not-A variants. Now X is done by the outer
multiclass, which allows me to bypass that one when I only want the
two not-X variants.

Changing the multiclass nesting order also changes the names of the
instruction ids unless I make a special effort not to. I decided that
while I was changing them anyway I'd make them look nicer; so now the
instructions have names like MVE_VMLADAVs32 or MVE_VMLADAVaxs32,
instead of cumbersome _noacc_noexch suffixes.

The corresponding multiply-subtract instructions are unaffected. Those
don't accept unsigned types at all, either in the spec or in LLVM.

Reviewers: ostannard, dmgreen

Subscribers: javed.absar, kristof.beyls, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67214

llvm-svn: 371405
2019-09-09 15:17:26 +00:00
Oliver Stannard 6b9aedaec6 [ARM][MVE] Decoding of uqrshl and sqrshl accepts unpredictable encodings
Specify the Unpredictable bits, and return softfails when appropriate.

Patch by Mark Murray!

Differential revision: https://reviews.llvm.org/D66939

llvm-svn: 371374
2019-09-09 08:50:28 +00:00
Fangrui Song 72e99e63a2 [ELF][MC] Set types of aliases of IFunc to STT_GNU_IFUNC
```
.type  foo,@gnu_indirect_function
.set   foo,foo_resolver

.set foo2,foo
.set foo3,foo2
```

The types of foo2 and foo3 should be STT_GNU_IFUNC, but we currently
resolve them to the type of foo_resolver. This patch fixes it.

Differential Revision: https://reviews.llvm.org/D67206
Patch by Senran Zhang

llvm-svn: 371312
2019-09-07 14:58:47 +00:00
Reid Kleckner b2d10cf22e [MC] Pass through .code16/32/64 and .syntax unified for COFF
These flags should simply be passed through to the target, which will do
the right thing. Add an MC/X86 test that uses these directives with the
three primary object file formats and shows that they disassemble the
same everywhere.

There is a missing test for .code32 on Windows ARM, since I'm not sure
exactly how to construct one.

Fixes PR43203

llvm-svn: 370805
2019-09-03 18:16:52 +00:00
David Green 2f3574c168 [ARM] Ignore Implicit CPSR regs when lowering from Machine to MC operands
The code here seems to date back to r134705, when tablegen lowering was first
being added. I don't believe that we need to include CPSR implicit operands on
the MCInst. This now works more like other backends (like AArch64), where all
implicit registers are skipped.

This allows the AliasInst for CSEL's to match correctly, as can be seen in the
test changes.

Differential revision: https://reviews.llvm.org/D66703

llvm-svn: 370745
2019-09-03 11:30:54 +00:00
Oliver Stannard 3be2df2418 [ARM][MVE] Decoding of VMSR doesn't diagnose some unpredictable encodings
Decoding of VMSR doesn't diagnose some unpredictable encodings, as the unpredictable bits are not correctly set.

Diff-reduce this instruction's internals WRT VMRS so I can see the differences better. Mostly this is s/src/Rt/g.

Fill in the "should-be-(0)" bits.

Designate the Unpredictable{} bits for both VMRS and VMSR.

Patch by Mark Murray!

Differential revision: https://reviews.llvm.org/D66938

llvm-svn: 370729
2019-09-03 09:55:30 +00:00
Dmitry Preobrazhensky 4aa90ea58e [AMDGPU][MC][GFX10] Corrected constant bus checks to exclude null
See AMD SWDEV-157286

Reviewers: atamazov, arsenm

Differential Revision: https://reviews.llvm.org/D65229

llvm-svn: 370665
2019-09-02 14:19:52 +00:00
Dmitry Preobrazhensky 9c68eddbbe [AMDGPU][MC][GFX10] Enabled null with 64-bit operands
See Bug 42745: https://bugs.llvm.org/show_bug.cgi?id=42745

Reviewers: atamazov, arsenm

https://reviews.llvm.org/D65231

llvm-svn: 370660
2019-09-02 13:42:25 +00:00
Dmitry Preobrazhensky fe2ee4c46a [AMDGPU][MC][GFX10] Corrected constant bus limit for 64-bit shift instructions
See bug 42744: https://bugs.llvm.org/show_bug.cgi?id=42744

Reviewers: atamazov, arsenm

Differential Revision: https://reviews.llvm.org/D65228

llvm-svn: 370652
2019-09-02 12:50:05 +00:00
Thomas Lively d0d9317061 [WebAssembly] Add SIMD QFMA/QFMS
Summary:
Adds clang builtins and LLVM intrinsics for these experimental
instructions. They are not implemented in engines yet, but that is ok
because the user must opt into using them by calling the builtins.

Reviewers: aheejin, dschuff

Reviewed By: aheejin

Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D67020

llvm-svn: 370556
2019-08-31 00:12:29 +00:00
Reid Kleckner 657a06c619 [MC] Avoid crashes from improperly nested or wrong target .seh_handlerdata directives
llvm-svn: 370540
2019-08-30 22:25:55 +00:00
Reid Kleckner a33474d595 [X86] Print register names in .seh_* directives
Also improve assembler parser register validation for .seh_ directives.
This requires moving X86-specific seh directive handling into the x86
backend, which addresses some assembler FIXMEs.

Differential Revision: https://reviews.llvm.org/D66625

llvm-svn: 370533
2019-08-30 21:23:05 +00:00
Dan Gohman da84b688f9 [WebAssembly] Make __attribute__((used)) not imply export.
Add an WASM_SYMBOL_NO_STRIP flag, so that __attribute__((used)) doesn't
need to imply exporting. When targeting Emscripten, have
WASM_SYMBOL_NO_STRIP imply exporting.

Differential Revision: https://reviews.llvm.org/D62542

llvm-svn: 370415
2019-08-29 22:40:00 +00:00
Jinsong Ji 1ed7d2119e [PowerPC] Support extended mnemonics mffprwz etc.
Summary:
Reported in https://github.com/opencv/opencv/issues/15413.

We have serveral extended mnemonics for Move To/From Vector-Scalar Register Instructions
eg: mffprd,mtfprd etc.

We only support one of them, this patch add the others.

Reviewers: nemanjai, steven.zhang, hfinkel, #powerpc

Reviewed By: hfinkel

Subscribers: wuzish, qcolombet, hiraditya, kbarton, MaskRay, shchenz, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66963

llvm-svn: 370411
2019-08-29 21:53:59 +00:00
Reid Kleckner 81e458d001 Allow '@' to appear in x86 mingw symbols
Summary:
There is no reason to differ in assembler behavior here between -msvc
and -gnu targets. Without this setting, the text after the '@' is
interpreted as a symbol variable, like foo@IMGREL.

Reviewers: mstorsjo

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66974

llvm-svn: 370408
2019-08-29 21:15:02 +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
Heejin Ahn d85fd5a3f4 [WebAssembly] Add atomic.fence instruction
Summary:
This adds `atomic.fence` instruction:
https://github.com/WebAssembly/threads/blob/master/proposals/threads/Overview.md#fence-operator

And we now emit the new `atomic.fence` instruction for multithread
fences, rather than the prevous `atomic.rmw` hack.

Reviewers: dschuff

Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, jfb, tlively, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66794

llvm-svn: 370272
2019-08-28 23:13:43 +00:00
Scott Linder 04f6f25421 [AMDGPU] Fix bug when calculating user_spgr_count for Code Object V3 assembler
Stop counting explicitly disabled user_spgr's in the user_sgpr_count field of the kernel descriptor.

Differential Revision: https://reviews.llvm.org/D66900

llvm-svn: 370250
2019-08-28 19:38:15 +00:00
Stanislav Mekhanoshin b37d6a750a [AMDGPU] Check for immediate SrcC in mfma in AsmParser
Differential Revision: https://reviews.llvm.org/D66674

llvm-svn: 369819
2019-08-23 22:22:49 +00:00
Manoj Gupta 30232770fb Revert r369233.
This breaks building of some projects like libfuse and alsa-lib
that now fail when linking.
Error details in PR43092.

llvm-svn: 369790
2019-08-23 18:01:13 +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