…133242)"
This reverts commit 130080fab11cde5efcb338b77f5c3b31097df6e6 because it
causes issues in testcases similar to coalescer_remat.ll [1], i.e. when
we use a VGPR tuple but only write to its lower parts. The high VGPRs
would then not be included in the vgpr_count, and accessing them would
be an out of bounds violation.
[1]
https://github.com/llvm/llvm-project/blob/main/llvm/test/CodeGen/AMDGPU/coalescer_remat.ll
Don't count register uses when determining the maximum number of
registers used by a function. Count only the defs. This is really an
underestimate of the true register usage, but in practice that's not
a problem because if a function uses a register, then it has either
defined it earlier, or some other function that executed before has
defined it.
In particular, the register counts are used:
1. When launching an entry function - in which case we're safe because
the register counts of the entry function will include the register
counts of all callees.
2. At function boundaries in dynamic VGPR mode. In this case it's safe
because whenever we set the new VGPR allocation we take into account
the outgoing_vgpr_count set by the middle-end.
The main advantage of doing this is that the artificial VGPR arguments
used only for preserving the inactive lanes when using the
llvm.amdgcn.init.whole.wave intrinsic are no longer counted. This
enables us to allocate only the registers we need in dynamic VGPR mode.
---------
Co-authored-by: Thomas Symalla <5754458+tsymalla@users.noreply.github.com>
Previously the AnnotateKernelFeatures pass infers two attributes:
amdgpu-calls and amdgpu-stack-objects, which are used to help determine
if flat scratch init is allowed. PR #118907 created the
amdgpu-no-flat-scratch-init attribute. Continuing with that work, this
patch makes use of this attribute to determine flat scratch init,
replacing amdgpu-calls and amdgpu-stack-objects. This also leads to the
removal of the AnnotateKernelFeatures pass.
The AMDGPUAnnotateKernelFeatures pass infers the "amdgpu-calls" and
"amdgpu-stack-objects" attributes, which are used to infer whether we
need to initialize flat scratch. This is, however, not precise. Instead,
we should use AMDGPUAttributor and infer amdgpu-no-flat-scratch-init on
kernels. Refer to https://github.com/llvm/llvm-project/issues/63586 .
Converts AMDGPUResourceUsageAnalysis pass from Module to MachineFunction
pass. Moves function resource info propagation to to MC layer (through
helpers in AMDGPUMCResourceInfo) by generating MCExprs for every
function resource which the emitters have been prepped for.
Fixes https://github.com/llvm/llvm-project/issues/64863
The previous name 'amdgpu_code_object_version', was misleading since
this is really a property of the HSA OS. The new spelling also matches
the asm directive I added in bc82cfb.
Code Object V2 has been deprecated for more than a year now. We can
safely remove it from LLVM.
- [clang] Remove support for the `-mcode-object-version=2` option.
- [lld] Remove/refactor tests that were still using COV2
- [llvm] Update AMDGPUUsage.rst
- Code Object V2 docs are left for informational purposes because those
code objects may still be supported by the runtime/loaders for a while.
- [AMDGPU] Remove COV2 emission capabilities.
- [AMDGPU] Remove `MetadataStreamerYamlV2` which was only used by COV2
- [AMDGPU] Update all tests that were still using COV2 - They are either
deleted or ported directly to code object v4 (as v3 is also planned to
be removed soon).
The issue is uncovered by #47698: for IR files without a target triple,
-mtriple= specifies the full target triple while -march= merely sets the
architecture part of the default target triple, leaving a target triple which
may not make sense, e.g. riscv64-apple-darwin.
Therefore, -march= is error-prone and not recommended for tests without a target
triple. The issue has been benign as we recognize $unknown-apple-darwin as ELF instead
of rejecting it outrightly.
Summary:
This patch introduces a mechanism to check the code object version from the module flag, This avoids checking from command line.
In case the module flag is missing, we use the current default code object version supported in the compiler.
For tools whose inputs are not IR, we may need other approach (directive, for example) to check the code
object version, That will be in a separate patch later.
For LIT tests update, we directly add module flag if there is only a single code object version associated with all checks in one file.
In cause of multiple code object version in one file, we use the "sed" method to "clone" the checks to achieve the goal.
Reviewer: arsenm
Differential Revision:
https://reviews.llvm.org/D14313
With architected flat scratch it becomes readonly. We must always
reserve SGPR pair for it even if we do not use scratch at all since
an attempt to write to SGPRs mapped to FLAT_SCRATCH results in
memory violation.
This is not needed since GFX10 with architected flat scratch though
since special SGPRs are not carving space from normal SGPRs.
Differential Revision: https://reviews.llvm.org/D110376
Support for XNACK and SRAMECC is not static on some GPUs. We must be able
to differentiate between different scenarios for these dynamic subtarget
features.
The possible settings are:
- Unsupported: The GPU has no support for XNACK/SRAMECC.
- Any: Preference is unspecified. Use conservative settings that can run anywhere.
- Off: Request support for XNACK/SRAMECC Off
- On: Request support for XNACK/SRAMECC On
GCNSubtarget will track the four options based on the following criteria. If
the subtarget does not support XNACK/SRAMECC we say the setting is
"Unsupported". If no subtarget features for XNACK/SRAMECC are requested we
must support "Any" mode. If the subtarget features XNACK/SRAMECC exist in the
feature string when initializing the subtarget, the settings are "On/Off".
The defaults are updated to be conservatively correct, meaning if no setting
for XNACK or SRAMECC is explicitly requested, defaults will be used which
generate code that can be run anywhere. This corresponds to the "Any" setting.
Differential Revision: https://reviews.llvm.org/D85882
Avoid looping through program to determine register counts.
This avoids needing to look at regmask operands.
Also fixes some counting errors with flat_scr when there
are no stack objects.
llvm-svn: 300482
Currently the default C calling convention functions are treated
the same as compute kernels. Make this explicit so the default
calling convention can be changed to a non-kernel.
Converted with perl -pi -e 's/define void/define amdgpu_kernel void/'
on the relevant test directories (and undoing in one place that actually
wanted a non-kernel).
llvm-svn: 298444
This switches to the workaround that HSA defaults to
for the mesa path.
This should be applied to the 4.0 branch.
Patch by Vedran Miletić <vedran@miletic.net>
llvm-svn: 292982
Summary:
Somehow, I first interpreted the docs as saying space for xnack_mask is only
reserved when XNACK is enabled via SH_MEM_CONFIG. I felt uneasy about this and
went back to actually test what is happening, and it turns out that xnack_mask
is always reserved at least on Tonga and Carrizo, in the sense that flat_scr
is always fixed below the SGPRs that are used to implement xnack_mask, whether
or not they are actually used.
I confirmed this by writing a shader using inline assembly to tease out the
aliasing between flat_scratch and regular SGPRs. For example, on Tonga, where
we fix the number of SGPRs to 80, s[74:75] aliases flat_scratch (so
xnack_mask is s[76:77] and vcc is s[78:79]).
This patch changes both the calculation of the total number of SGPRs and the
various register reservations to account for this.
It ought to be possible to use the gap left by xnack_mask when the feature
isn't used, but this patch doesn't try to do that. (Note that the same applies
to vcc.)
Note that previously, even before my earlier change in r256794, the SGPRs that
alias to xnack_mask could end up being used as well when flat_scr was unused
and the total number of SGPRs happened to fall on the right alignment
(e.g. highest regular SGPR being used s29 and VCC used would lead to number
of SGPRs being 32, where s28 and s29 alias with xnack_mask). So if there
were some conflict due to such aliasing, we should have noticed that already.
Reviewers: arsenm, tstellarAMD
Subscribers: arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D15898
llvm-svn: 257073
Summary:
Enabling this feature will account for the two SGPRs used by the hardware
to store the XNACK_MASK physically.
The hardware only requires this reservation when the XNACK feature is
explicitly enabled. At some point, HSA will probably want to do that, but
it does increase SGPR register pressure, so leave it disabled by default
for now (but do add a small test).
Reviewers: arsenm, tstellarAMD
Subscribers: arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D15869
llvm-svn: 256794
