20 Commits

Author SHA1 Message Date
Stanislav Mekhanoshin
fe197ef9f1 [AMDGPU] Mark relevant rematerializable VOP3 instructions
Differential Revision: https://reviews.llvm.org/D106110
2021-07-21 14:44:13 -07:00
Matt Arsenault
fae05692a3 CodeGen: Print/parse LLTs in MachineMemOperands
This will currently accept the old number of bytes syntax, and convert
it to a scalar. This should be removed in the near future (I think I
converted all of the tests already, but likely missed a few).

Not sure what the exact syntax and policy should be. We can continue
printing the number of bytes for non-generic instructions to avoid
test churn and only allow non-scalar types for generic instructions.

This will currently print the LLT in parentheses, but accept parsing
the existing integers and implicitly converting to scalar. The
parentheses are a bit ugly, but the parser logic seems unable to deal
without either parentheses or some keyword to indicate the start of a
type.
2021-06-30 16:54:13 -04:00
Stanislav Mekhanoshin
3bffb1cd0e [AMDGPU] Use single cache policy operand
Replace individual operands GLC, SLC, and DLC with a single cache_policy
bitmask operand. This will reduce the number of operands in MIR and I hope
the amount of code. These operands are mostly 0 anyway.

Additional advantage that parser will accept these flags in any order unlike
now.

Differential Revision: https://reviews.llvm.org/D96469
2021-03-15 13:00:59 -07:00
Ruiling Song
f0ccdde3c9 [AMDGPU] Remove SI_MASK_BRANCH
This is already deprecated, so remove code working on this.
Also update the tests by using S_CBRANCH_EXECZ instead of SI_MASK_BRANCH.

Reviewed By: foad

Differential Revision: https://reviews.llvm.org/D97545
2021-03-09 09:13:23 +08:00
Stanislav Mekhanoshin
a8d9d50762 [AMDGPU] gfx90a support
Differential Revision: https://reviews.llvm.org/D96906
2021-02-17 16:01:32 -08:00
Joe Nash
314e29ed2b [AMDGPU] Add _e64 suffix to VOP3 Insts
Previously, instructions which could be
expressed as VOP3 in addition to another
encoding had a _e64 suffix on the tablegen
record name, while those
only available as VOP3 did not. With this
patch, all VOP3s will have the _e64 suffix.
The assembly does not change, only  the mir.

Reviewed By: foad

Differential Revision: https://reviews.llvm.org/D94341

Change-Id: Ia8ec8890d47f8f94bbbdac43745b4e9dd2b03423
2021-01-12 18:33:18 -05:00
Stanislav Mekhanoshin
5ab1702129 [AMDGPU] Remove scratch rsrc from spill pseudos
Differential Revision: https://reviews.llvm.org/D91110
2020-11-12 15:23:37 -08:00
Jay Foad
6f6d389da5 [SplitKit] Only copy live lanes
When splitting a live interval with subranges, only insert copies for
the lanes that are live at the point of the split. This avoids some
unnecessary copies and fixes a problem where copying dead lanes was
generating MIR that failed verification. The test case for this is
test/CodeGen/AMDGPU/splitkit-copy-live-lanes.mir.

Without this fix, some earlier live range splitting would create %430:

%430 [256r,848r:0)[848r,2584r:1)  0@256r 1@848r L0000000000000003 [848r,2584r:0)  0@848r L0000000000000030 [256r,2584r:0)  0@256r weight:1.480938e-03
...
256B     undef %430.sub2:vreg_128 = V_LSHRREV_B32_e32 16, %20.sub1:vreg_128, implicit $exec
...
848B     %430.sub0:vreg_128 = V_AND_B32_e32 %92:sreg_32, %20.sub1:vreg_128, implicit $exec
...
2584B    %431:vreg_128 = COPY %430:vreg_128

Then RAGreedy::tryLocalSplit would split %430 into %432 and %433 just
before 848B giving:

%432 [256r,844r:0)  0@256r L0000000000000030 [256r,844r:0)  0@256r weight:3.066802e-03
%433 [844r,848r:0)[848r,2584r:1)  0@844r 1@848r L0000000000000030 [844r,2584r:0)  0@844r L0000000000000003 [844r,844d:0)[848r,2584r:1)  0@844r 1@848r weight:2.831776e-03
...
256B     undef %432.sub2:vreg_128 = V_LSHRREV_B32_e32 16, %20.sub1:vreg_128, implicit $exec
...
844B     undef %433.sub0:vreg_128 = COPY %432.sub0:vreg_128 {
           internal %433.sub2:vreg_128 = COPY %432.sub2:vreg_128
848B     }
  %433.sub0:vreg_128 = V_AND_B32_e32 %92:sreg_32, %20.sub1:vreg_128, implicit $exec
...
2584B    %431:vreg_128 = COPY %433:vreg_128

Note that the copy from %432 to %433 at 844B is a curious
bundle-without-a-BUNDLE-instruction that SplitKit creates deliberately,
and it includes a copy of .sub0 which is not live at this point, and
that causes it to fail verification:

*** Bad machine code: No live subrange at use ***
- function:    zextload_global_v64i16_to_v64i64
- basic block: %bb.0  (0x7faed48) [0B;2848B)
- instruction: 844B    undef %433.sub0:vreg_128 = COPY %432.sub0:vreg_128
- operand 1:   %432.sub0:vreg_128
- interval:    %432 [256r,844r:0)  0@256r L0000000000000030 [256r,844r:0)  0@256r weight:3.066802e-03
- at:          844B

Using real bundles with a BUNDLE instruction might also fix this
problem, but the current fix is less invasive and also avoids some
unnecessary copies.

https://bugs.llvm.org/show_bug.cgi?id=47492

Differential Revision: https://reviews.llvm.org/D87757
2020-09-17 09:26:11 +01:00
Matt Arsenault
4b4496312e AMDGPU: Start adding MODE register uses to instructions
This is the groundwork required to implement strictfp. For now, this
should be NFC for regular instructoins (many instructions just gain an
extra use of a reserved register). Regalloc won't rematerialize
instructions with reads of physical registers, but we were suffering
from that anyway with the exec reads.

Should add it for all the related FP uses (possibly with some
extras). I did not add it to either the gpr index mode instructions
(or every single VALU instruction) since it's a ridiculous feature
already modeled as an arbitrary side effect.

Also work towards marking instructions with FP exceptions. This
doesn't actually set the bit yet since this would start to change
codegen. It seems nofpexcept is currently not implied from the regular
IR FP operations. Add it to some MIR tests where I think it might
matter.
2020-05-27 14:47:00 -04:00
Jay Foad
0337017a9f [AMDGPU] Use SGPR instead of SReg classes
12994a70cf7 did this for 128-bit classes:

    SGPR_128 only includes the real allocatable SGPRs, and SReg_128 adds
    the additional non-allocatable TTMP registers. There's no point in
    allocating SReg_128 vregs. This shrinks the size of the classes
    regalloc needs to consider, which is usually good.

This patch extends it to all classes > 64 bits, for consistency.

Differential Revision: https://reviews.llvm.org/D78622
2020-04-23 11:45:22 +01:00
Scott Linder
60b1967c39 [AMDGPU] Add Scratch Wave Offset to Scratch Buffer Descriptor in entry functions
Add the scratch wave offset to the scratch buffer descriptor (SRSrc) in
the entry function prologue. This allows us to removes the scratch wave
offset register from the calling convention ABI.

As part of this change, allow the use of an inline constant zero for the
SOffset of MUBUF instructions accessing the stack in entry functions
when a frame pointer is not requested/required. Entry functions with
calls still need to set up the calling convention ABI stack pointer
register, and reference it in order to address arguments of called
functions. The ABI stack pointer register remains unswizzled, but is now
wave-relative instead of queue-relative.

Non-entry functions also use an inline constant zero SOffset for
wave-relative scratch access, but continue to use the stack and frame
pointers as before. When the stack or frame pointer is converted to a
swizzled offset it is now scaled directly, as the scratch wave offset no
longer needs to be subtracted first.

Update llvm/docs/AMDGPUUsage.rst to reflect these changes to the calling
convention.

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75138
2020-03-19 15:35:16 -04:00
Matt Arsenault
12994a70cf AMDGPU: Use SGPR_128 instead of SReg_128 for vregs
SGPR_128 only includes the real allocatable SGPRs, and SReg_128 adds
the additional non-allocatable TTMP registers. There's no point in
allocating SReg_128 vregs. This shrinks the size of the classes
regalloc needs to consider, which is usually good.

llvm-svn: 374284
2019-10-10 07:11:33 +00:00
Matt Arsenault
b812b7a45e AMDGPU: Invert frame index offset interpretation
Since the beginning, the offset of a frame index has been consistently
interpreted backwards. It was treating it as an offset from the
scratch wave offset register as a frame register. The correct
interpretation is the offset from the SP on entry to the function,
before the prolog. Frame index elimination then should select either
SP or another register as an FP.

Treat the scratch wave offset on kernel entry as the pre-incremented
SP. Rely more heavily on the standard hasFP and frame pointer
elimination logic, and clean up the private reservation code. This
saves a copy in most callee functions.

The kernel prolog emission code is still kind of a mess relying on
checking the uses of physical registers, which I would prefer to
eliminate.

Currently selection directly emits MUBUF instructions, which require
using a reference to some register. Use the register chosen for SP,
and then ignore this later. This should probably be cleaned up to use
pseudos that don't refer to any specific base register until frame
index elimination.

Add a workaround for shaders using large numbers of SGPRs. I'm not
sure these cases were ever working correctly, since as far as I can
tell the logic for figuring out which SGPR is the scratch wave offset
doesn't match up with the shader input initialization in the shader
programming guide.

llvm-svn: 362661
2019-06-05 22:20:47 +00:00
Stanislav Mekhanoshin
a6322941ff [AMDGPU] gfx1010 VMEM and SMEM implementation
Differential Revision: https://reviews.llvm.org/D61330

llvm-svn: 359621
2019-04-30 22:08:23 +00:00
Tim Renouf
2e94f6e584 [AMDGPU] Asm/disasm v_cndmask_b32_e64 with abs/neg source modifiers
This commit allows v_cndmask_b32_e64 with abs, neg source
modifiers on src0, src1 to be assembled and disassembled.

This does appear to be allowed, even though they are floating point
modifiers and the operand type is b32.

To do this, I added src0_modifiers and src1_modifiers to the
MachineInstr, which involved fixing up several places in codegen and mir
tests.

Differential Revision: https://reviews.llvm.org/D59191

Change-Id: I69bf4a8c73ebc65744f6110bb8fc4e937d79fbea
llvm-svn: 356398
2019-03-18 19:25:39 +00:00
Matt Arsenault
bc6d07ca46 MIR: Allow targets to serialize MachineFunctionInfo
This has been a very painful missing feature that has made producing
reduced testcases difficult. In particular the various registers
determined for stack access during function lowering were necessary to
avoid undefined register errors in a large percentage of
cases. Implement a subset of the important fields that need to be
preserved for AMDGPU.

Most of the changes are to support targets parsing register fields and
properly reporting errors. The biggest sort-of bug remaining is for
fields that can be initialized from the IR section will be overwritten
by a default initialized machineFunctionInfo section. Another
remaining bug is the machineFunctionInfo section is still printed even
if empty.

llvm-svn: 356215
2019-03-14 22:54:43 +00:00
David Stuttard
20ea21c6ed [AMDGPU] Add support for immediate operand for S_ENDPGM
Summary:
Add support for immediate operand in S_ENDPGM

Change-Id: I0c56a076a10980f719fb2a8f16407e9c301013f6

Reviewers: alexshap

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59213

llvm-svn: 355902
2019-03-12 09:52:58 +00:00
John Brawn
1d0d86ae40 [RegAllocGreedy] IMPLICIT_DEF values shouldn't prefer registers
It costs nothing to spill an IMPLICIT_DEF value (the only spill code that's
generated is a KILL of the value), so when creating split constraints if the
live-out value is IMPLICIT_DEF the exit constraint should be DontCare instead
of PrefReg.

Differential Revision: https://reviews.llvm.org/D55652

llvm-svn: 349151
2018-12-14 14:07:57 +00:00
Matt Arsenault
709374d186 AMDGPU: Improve hack for packing conversion ops
Mutate the node type during selection when it
doesn't matter. This avoids an intermediate bitcast
node on targets with legal i16/f16.

Also fixes missing output modifiers on v_cvt_pkrtz_f32_f16,
which I assume are OK.

llvm-svn: 338619
2018-08-01 20:13:58 +00:00
Krzysztof Parzyszek
70f027022c Account for undef values from predecessors in extendSegmentsToUses
It is legal for a PHI node not to have a live value in a predecessor
as long as the end of the predecessor is jointly dominated by an undef
value.

llvm-svn: 335607
2018-06-26 14:37:16 +00:00