Commit Graph

16 Commits

Author SHA1 Message Date
Dmitry Preobrazhensky 6b8948922c [AMDGPU][MC] Added support of SP3 syntax for MTBUF format modifier
Currently supported LLVM MTBUF syntax is shown below. It is not compatible with SP3.

    op     dst, addr, rsrc, FORMAT, soffset

This change adds support for SP3 syntax:

    op     dst, addr, rsrc, soffset SP3FORMAT

In addition to being compatible with SP3, this syntax allows using symbolic names for data, numeric and unified formats. Below is a list of added syntax variants.

format:<expression>
format:[<numeric-format-name>,<data-format-name>]
format:[<data-format-name>,<numeric-format-name>]
format:[<data-format-name>]
format:[<numeric-format-name>]
format:[<unified-format-name>]

The last syntax variant is supported for GFX10 only.

See llvm bug 37738

Reviewers: arsenm, rampitec, vpykhtin

Differential Revision: https://reviews.llvm.org/D84026
2020-07-24 16:41:03 +03:00
Dmitry Preobrazhensky 0b8fd77ad9 [AMDGPU][MC] Corrected decoding of 16-bit literals
16-bit literals are encoded as 32-bit values. If high 16-bits of the value is 0xFFFF, the decoded instruction cannot be reassembled.

For example, the following code

0xff,0x04,0x04,0x52,0xcd,0xab,0xff,0xff

was decoded as

v_mul_lo_u16_e32 v2, 0xffffabcd, v2

However this literal is actually a 64-bit constant 0x00000000ffffabcd which violates requirements described in the documentation - the truncation is not safe.

This change corrects decoding to make reassembly possible.

Reviewers: arsenm, rampitec

Differential Revision: https://reviews.llvm.org/D84098
2020-07-22 17:20:43 +03:00
Matt Arsenault 5f5f566b26 AMDGPU: Don't use 16-bit FP inline constants in integer operands
It seems to be a hardware defect that the half inline constants do not
work as expected for the 16-bit integer operations (the inverse does
work correctly). Experimentation seems to show these are really
reading the 32-bit inline constants, which can be observed by writing
inline asm using op_sel to see what's in the high half of the
constant. Theoretically we could fold the high halves of the 32-bit
constants using op_sel.

The *_asm_all.s MC tests are broken, and I don't know where the script
to autogenerate these are. I started manually fixing it, but there's
just too many cases to fix. This also does break the
assembler/disassembler support for these values, and I'm not sure what
to do about it. These are still valid encodings, so it seems like you
should be able to use them in some way. If you wrote assembly using
them, you could have really meant it (perhaps to read the high bits
with op_sel?). The disassembler will print the invalid literal
constant which will fail to re-assemble. The behavior is also
different depending on the use context. Consider this example, which
was previously accepted and encoded using the inline constant:

  v_mad_i16 v5, v1, -4.0, v3
  ; encoding: [0x05,0x00,0xec,0xd1,0x01,0xef,0x0d,0x04]

In contexts where an inline immediate is required (such as on gfx8/9),
this will now be rejected. For gfx10, this will produce the literal
encoding and change the printed format:
  v_mad_i16 v5, v1, 0xc400, v3
  ; encoding: [0x05,0x00,0x5e,0xd7,0x01,0xff,0x0d,0x04,0x00,0xc4,0x00,0x00]

This is just another variation of the issue that we don't perfectly
handle round trip assembly/disassembly due to not tracking how
immediates were encoded. This doesn't matter much in practice, since
compilers don't emit the suboptimal encoding. I doubt any users are
relying on this behavior (although I did make use of the old behavior
to figure out what was wrong).

Fixes bug 46302.
2020-06-17 19:14:10 -04:00
Dmitry Preobrazhensky 5998baccb9 [AMDGPU][MC][GFX9+] Enabled 21-bit signed offsets for SMEM instructions
Reviewers: arsenm, rampitec

Differential Revision: https://reviews.llvm.org/D79288
2020-05-06 14:13:10 +03:00
Fangrui Song 5fad05e80d [MCInstPrinter] Pass `Address` parameter to MCOI::OPERAND_PCREL typed operands. NFC
Follow-up of D72172 and D72180

This patch passes `uint64_t Address` to print methods of PC-relative
operands so that subsequent target specific patches can change
`*InstPrinter::print{Operand,PCRelImm,...}` to customize the output.

Add MCInstPrinter::PrintBranchImmAsAddress which is set to true by
llvm-objdump.

```
// Current llvm-objdump -d output
aarch64: 20000: bl #0
ppc:     20000: bl .+4
x86:     20000: callq 0

// Ideal output
aarch64: 20000: bl 0x20000
ppc:     20000: bl 0x20004
x86:     20000: callq 0x20005

// GNU objdump -d. The lack of 0x is not ideal because the result cannot be re-assembled
aarch64: 20000: bl 20000
ppc:     20000: bl 0x20004
x86:     20000: callq 20005
```

In `lib/Target/X86/X86GenAsmWriter1.inc` (generated by `llvm-tblgen -gen-asm-writer`):

```
   case 12:
     // CALL64pcrel32, CALLpcrel16, CALLpcrel32, EH_SjLj_Setup, JCXZ, JECXZ, J...
-    printPCRelImm(MI, 0, O);
+    printPCRelImm(MI, Address, 0, O);
     return;
```

Some targets have 2 `printOperand` overloads, one without `Address` and
one with `Address`. They should annotate derived `Operand` properly with
`let OperandType = "OPERAND_PCREL"`.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D76574
2020-03-26 08:21:15 -07:00
Scott Linder 481b1c8380 [AMDGPU] Implement wave64 DWARF register mapping
Summary:
Implement the DWARF register mapping described in
llvm/docs/AMDGPUUsage.rst

This is currently limited to wave64 VGPRs/AGPRs.

This also includes some minor changes in AMDGPUInstPrinter,
AMDGPUMCTargetDesc, and AMDGPUAsmParser to make generating CFI assembly
text and ELF sections possible to ease testing, although complete CFI
support is not yet implemented.

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74915
2020-02-25 14:00:01 -05:00
Sebastian Neubauer 8756869170 [AMDGPU] Add a16 feature to gfx10
Based on D72931

This adds a new feature called A16 which is enabled for gfx10.
gfx9 keeps the R128A16 feature so it can share all the instruction encodings
with gfx7/8.

Differential Revision: https://reviews.llvm.org/D73956
2020-02-10 09:04:23 +01:00
Fangrui Song 3d87d0b925 [MC] Add parameter `Address` to MCInstrPrinter::printInstruction
Follow-up of D72172.

Reviewed By: jhenderson, rnk

Differential Revision: https://reviews.llvm.org/D72180
2020-01-06 20:44:14 -08:00
Fangrui Song aa708763d3 [MC] Add parameter `Address` to MCInstPrinter::printInst
printInst prints a branch/call instruction as `b offset` (there are many
variants on various targets) instead of `b address`.

It is a convention to use address instead of offset in most external
symbolizers/disassemblers. This difference makes `llvm-objdump -d`
output unsatisfactory.

Add `uint64_t Address` to printInst(), so that it can pass the argument to
printInstruction(). `raw_ostream &OS` is moved to the last to be
consistent with other print* methods.

The next step is to pass `Address` to printInstruction() (generated by
tablegen from the instruction set description). We can gradually migrate
targets to print addresses instead of offsets.

In any case, downstream projects which don't know `Address` can pass 0 as
the argument.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D72172
2020-01-06 20:42:22 -08:00
Piotr Sobczak 265e94e657 [AMDGPU] Extend buffer intrinsics with swizzling
Summary:
Extend cachepolicy operand in the new VMEM buffer intrinsics
to supply information whether the buffer data is swizzled.
Also, propagate this information to MIR.

Intrinsics updated:
int_amdgcn_raw_buffer_load
int_amdgcn_raw_buffer_load_format
int_amdgcn_raw_buffer_store
int_amdgcn_raw_buffer_store_format
int_amdgcn_raw_tbuffer_load
int_amdgcn_raw_tbuffer_store
int_amdgcn_struct_buffer_load
int_amdgcn_struct_buffer_load_format
int_amdgcn_struct_buffer_store
int_amdgcn_struct_buffer_store_format
int_amdgcn_struct_tbuffer_load
int_amdgcn_struct_tbuffer_store

Furthermore, disable merging of VMEM buffer instructions
in SI Load/Store optimizer, if the "swizzled" bit on the instruction
is on.

The default value of the bit is 0, meaning that data in buffer
is linear and buffer instructions can be merged.

There is no difference in the generated code with this commit.
However, in the future it will be expected that front-ends
use buffer intrinsics with correct "swizzled" bit set.

Reviewers: arsenm, nhaehnle, tpr

Reviewed By: nhaehnle

Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, arphaman, jfb, Petar.Avramovic, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68200

llvm-svn: 373491
2019-10-02 17:22:36 +00:00
Stanislav Mekhanoshin 01fcf9238f [AMDGPU] Allow register tuples to set asm names
This change reverts most of the previous register name generation.
The real problem is that RegisterTuple does not generate asm names.
Added optional operand to RegisterTuple. This way we can simplify
register name access and dramatically reduce the size of static
tables for the backend.

Differential Revision: https://reviews.llvm.org/D64967

llvm-svn: 366598
2019-07-19 18:05:01 +00:00
Stanislav Mekhanoshin e5012ab308 [AMDGPU] Autogenerate register asm names
Differential Revision: https://reviews.llvm.org/D64839

llvm-svn: 366283
2019-07-16 23:44:21 +00:00
Stanislav Mekhanoshin 50d7f46460 [AMDGPU] gfx908 mAI instructions, MC part
Differential Revision: https://reviews.llvm.org/D64446

llvm-svn: 365563
2019-07-09 21:43:09 +00:00
Dmitry Preobrazhensky 2eff0318c6 [AMDGPU][MC] Corrected parsing of FLAT offset modifier
Summary of changes:

- simplified handling of FLAT offset: offset_s13 and offset_u12 have been replaced with flat_offset;
- provided information about error position for pre-gfx9 targets;
- improved errors handling.

Reviewers: artem.tamazov, arsenm, rampitec

Differential Revision: https://reviews.llvm.org/D64244

llvm-svn: 365321
2019-07-08 14:27:37 +00:00
Stanislav Mekhanoshin 245b5ba344 [AMDGPU] gfx1010 dpp16 and dpp8
Differential Revision: https://reviews.llvm.org/D63203

llvm-svn: 363186
2019-06-12 18:02:41 +00:00
Richard Trieu c0bd7bd481 [AMDGPU] Move InstPrinter files to MCTargetDesc. NFC
For some targets, there is a circular dependency between InstPrinter and
MCTargetDesc.  Merging them together will fix this.  For the other targets,
the merging is to maintain consistency so all targets will have the same
structure.

llvm-svn: 360487
2019-05-11 00:03:35 +00:00