Extract the scratch offset from the scratch buffer descriptor that is
stored in the global table.
Differential Revision: https://reviews.llvm.org/D91701
To accommodate frame layouts that have both fixed and scalable objects
on the stack, describing a stack location or offset using a pointer + uint64_t
is not sufficient. For this reason, we've introduced the StackOffset class,
which models both the fixed- and scalable sized offsets.
The TargetFrameLowering::getFrameIndexReference is made to return a StackOffset,
so that this can be used in other interfaces, such as to eliminate frame indices
in PEI or to emit Debug locations for variables on the stack.
This patch is purely mechanical and doesn't change the behaviour of how
the result of this function is used for fixed-sized offsets. The patch adds
various checks to assert that the offset has no scalable component, as frame
offsets with a scalable component are not yet supported in various places.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D90018
This reverts r227987 "R600/SI: Determine target-specific encoding of READLANE and WRITELANE early v2".
All the codegen changes are caused by the post-RA scheduler no longer
treating readlane/writelane as scheduling barriers due to having
unmodelled side effects. (The pseudos are hasSideEffects = 0, but the
real instructions are hasSideEffects = ? which TableGen conservatively
treats as 1.)
Differential Revision: https://reviews.llvm.org/D90401
The support is disabled by default. So far there is instruction
selection, spilling, and frame elimination. It also changes SP
from unswizzled to swizzled as used by flat scratch instructions,
so it cannot be mixed with MUBUF stack access.
At the very least missing:
- GlobalISel;
- Some optimizations in frame elimination in between vector
and scalar ALU;
- It shall finally allow to always materialize frame index
as an SGPR, but that is not implemented and frame elimination
cannot handle it yet;
- Unaligned and/or multidword flat scratch shall work, but it
is legalized now for MUBUF;
- Operand folding cannot optimize FI like with MUBUF yet;
- It will need scaling the value of the SP/FP in the DWARF
expression to recover the unswizzled scratch address;
Differential Revision: https://reviews.llvm.org/D89170
During the PEI pass, the dead TargetStackID::SGPRSpill spill slots
are not being removed while spilling the FP/BP to memory.
Fixes: SWDEV-250393
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D87032
The SGPR spills happen in SILowerSGPRSpills() and allSGPRSpillsAreDead()
make sure there are no SGPR spills pending during PEI. But the FP/BP
spills happen during PEI and are exceptions.
Use actual frame indices of FP/BP in allSGPRSpillsAreDead() to
accommodate the exceptions.
Differential Revision: https://reviews.llvm.org/D86291
If we need a scratch register for the spill don't use the same scratch
register that is being used for the MBUF offset.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D85772
Summary:
Future patch needs some of these in multiple places.
The definitions of these can't be in the header and be eligible for
inlining without making the full declaration of GCNSubtarget visible.
I'm not sure what the right trade-off is, but I opted to not bloat
SIRegisterInfo.h
Reviewers: arsenm, cdevadas
Reviewed By: arsenm
Subscribers: RamNalamothu, qcolombet, jvesely, wdng, nhaehnle, hiraditya, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D79878
When the callee requires a dynamic stack realignment,
it is not possible to correcty access the incoming
stack arguments using the stack pointer. We reserve a
base pointer in such cases to access the function arguments
inside the callee. The base pointer will hold the incoming
stack pointer value before any kind of delta added to it.
Reviewed By: arsenm, scott.linder
Differential Revision: https://reviews.llvm.org/D78811
If there are no available lanes in a reserved VGPR, no free SGPR, and no unused CSR
VGPR when trying to save the FP it needs to be spilled to memory as a last
resort. This can be done in the prolog/epilog if we manually add the spill
and manage exec.
Differential Revision: https://reviews.llvm.org/D79610
Since SRSRC has alignment requirements, first find non GIT pointer clobbered
registers for SRSRC and then if those registers clobber preloaded Scratch Wave
Offset register, copy the Scratch Wave Offset register to a free SGPR.
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
Remove dead code and factor repeated conditions out into a single check.
Rename and move code to make it more obvious what is running only for
entry functions. Simplify function arguments to make it clearer what the
relevant inputs are. Make flat scratch init accept an MBB iterator and
move it to where it was logically being emitted within the prologue.
These changes will make a future update to the calling convention
simpler.
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D75092
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: jholewinski, arsenm, dschuff, jyknight, sdardis, nemanjai, jvesely, nhaehnle, sbc100, jgravelle-google, hiraditya, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D76348
I believe this also fixes bugs with CI 32-bit handling, which was
incorrectly skipping offsets that look like signed 32-bit values. Also
validate the offsets are dword aligned before folding.
Summary:
The only useful information the UndefValue conveys is the address space,
which MachinePointerInfo can represent directly without referring to an
IR value.
Reviewers: arsenm, rampitec
Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, Petar.Avramovic, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71838
Adds support to AArch64FrameLowering to allocate fixed-stack SVE objects.
The focus of this patch is purely to allow the stack frame to
allocate/deallocate space for scalable SVE objects. More dynamic
allocation (at compile-time, i.e. determining placement of SVE objects
on the stack), or resolving frame-index references that include
scalable-sized offsets, are left for subsequent patches.
SVE objects are allocated in the stack frame as a separate region below
the callee-save area, and above the alignment gap. This is done so that
the SVE objects can be accessed directly from the FP at (runtime)
VL-based offsets to benefit from using the VL-scaled addressing modes.
The layout looks as follows:
+-------------+
| stack arg |
+-------------+
| Callee Saves|
| X29, X30 | (if available)
|-------------| <- FP (if available)
| : |
| SVE area |
| : |
+-------------+
|/////////////| alignment gap.
| : |
| Stack objs |
| : |
+-------------+ <- SP after call and frame-setup
SVE and non-SVE stack objects are distinguished using different
StackIDs. The offsets for objects with TargetStackID::SVEVector should be
interpreted as purely scalable offsets within their respective SVE region.
Reviewers: thegameg, rovka, t.p.northover, efriedma, rengolin, greened
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D61437
llvm-svn: 373585
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
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
Make the FP register callee saved.
This is tricky because now the FP needs to be spilled in the prolog
relative to the incoming SP register, rather than the frame register
used throughout the rest of the function. I don't like how this
bypassess the standard mechanism for CSR spills just to get the
correct insert point. I may look for a better solution, since all CSR
VGPRs may also need to have all lanes activated. Another option might
be to make getFrameIndexReference change the base register if the
frame index is a CSR, and then try to figure out the right insertion
point in emitProlog.
If there is a free VGPR lane available for SGPR spilling, try to use
it for the FP. If that would require intrtoducing a new VGPR spill,
try to use a free call clobbered SGPR. Only fallback to introducing a
new VGPR spill as a last resort.
This also doesn't attempt to handle SGPR spilling with scalar stores.
llvm-svn: 365372
This is split out from my patches to split register allocation into a
separate SGPR and VGPR phase, and has some parts that aren't yet used
(like maintaining LiveIntervals).
This simplifies making the frame pointer register callee saved. As it
is now, the code to determine callee saves needs to predict all the
possible SGPR spills and how many callee saved VGPRs are needed. By
handling this before PrologEpilogInserter, it's possible to just check
the spill objects that already exist.
Change-Id: I29e6df4034afcf949e06f8ef44206acb94696f04
llvm-svn: 365095
The LivePhysRegs calculated in order to find a scratch register in the
epilogue code wrongly uses 'LiveIns'. Instead, it should use the
'Liveout' sets. For the liveness, also considering the operands of
the terminator (return) instruction which is the insertion point for
the scratch-exec-copy instruction.
Patch by Christudasan Devadasan
llvm-svn: 364470
The attribute can specify elimination for leaf or non-leaf, so it
should always be considered. I copied this bug from AArch64, which
probably should also be fixed.
llvm-svn: 363949
This patch changes MIR stack-id from an integer to an enum,
and adds printing/parsing support for this in MIR files. The default
stack-id '0' is now renamed to 'default'.
This should make MIR tests that have stack objects with different stack-ids
more descriptive. It also clarifies code operating on StackID.
Reviewers: arsenm, thegameg, qcolombet
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D60137
llvm-svn: 363533
Sebastian Neubauer