- Rename AMDGPU SCC DWARF register to STATUS since the scalar
condition code is a bit within the STATUS register.
- Correct bit size of the VCC_64 register to 64 which is the size in
wave64 mode.
Differential Revision: https://reviews.llvm.org/D86259
- Clarify that these are extensions to DWARF 5 and not as yet a
proposal.
Reviewed By: scott.linder
Differential Revision: https://reviews.llvm.org/D70523
- Clarify what context is used in DWARF expression evaluation.
- Define location descriptions to fully resolve the context and so
include the context in their result.
- As a consequence of location descriptions being fully resoved,
change address spaces so only a swizzled and unswizzled private
address space is defined. The lane is now part of the location
description context.
- Clarify how call frame information is used to fully resolve
expressions that specify registers.
Reviewed By: scott.linder
Differential Revision: https://reviews.llvm.org/D70523
This doesn't appear used for anything, and is emitted incorrectly
based on the description. This also depends on the IR type, and
pointee element type.
Private pointers used to workaround IR semantics by artifically
reserving an object at offset 0 so no user object would be allocated
there. Since alloca now uses a non-0 address space, that workaround is
unnecssary and 0 can be treated as a valid pointer.
Summary:
- Correct missing space in some "note" and "TODO" directives in
AMDGPUUsage.rst
- Correct warning for heading underline being too short in
BitCodeFormat.rst
Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D80407
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
The AMDGPU target has a convention that defined all VGPRs
(execept the initial 32 argument registers) as callee-saved.
This convention is not efficient always, esp. when the callee
requiring more registers, ended up emitting a large number of
spills, even though its caller requires only a few.
This patch revises the ABI by introducing more scratch registers
that a callee can freely use.
The 256 vgpr registers now become:
32 argument registers
112 scratch registers and
112 callee saved registers.
The scratch registers and the CSRs are intermixed at regular
intervals (a split boundary of 8) to obtain a better occupancy.
Reviewers: arsenm, t-tye, rampitec, b-sumner, mjbedy, tpr
Reviewed By: arsenm, t-tye
Differential Revision: https://reviews.llvm.org/D76356
- Unify the sections on DWARF expression and location lists.
- Allow a location description to have one or more single location
descriptions.
- Define context of DWARF expression that includes an initial
stack. Allow initial stack to be used when evaluating location list
expression with overlapping PC ranges.
- Reorganize the DWARF proposal in AMDGPUUsage so suitable for
submission to the DWARF site.
- Replace CFI instruction DW_CFA_LLVM_def_cfa_aspace with
DW_CFA_def_aspace_cfa and DW_CFA_def_aspace_cfa_sf. This is to avoid
the problem that DW_CFA_def_cfa and DW_CFA_def_cfa_sf cannot use a
register that is not the size of an address in the CFA address
space.
- Clarify DWARF address class and DWARF address space. Define language
values for DWARF address classes and specify how they are used by
some common source languages.
- Define rules for accessing registers and derefencing memory when the
type size and register size or byte size operand do not match.
- Numerous cleanups for consistency.
Differential Revision: https://reviews.llvm.org/D70523
Remove the gap left between the stack pointer (s32) and frame pointer
(s34) now that the scratch wave offset is no longer a part of the
calling convention ABI.
Update llvm/docs/AMDGPUUsage.rst to reflect the change.
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D75657
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
Summary:
- Clarify AMDGPU address spaces.
- Correct path to AMDGPU backend since now in the mono-repo.
- Fix numerous text style and typo issues.
- Correct reStructure text formatting warnings.
- Made reStructure directive usage more consistent.
- Add references for gfx10 ISA specification.
Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71392
Hostcall is a service that allows a kernel to submit requests to the
host using shared buffers, and block until a response is
received. This will eventually replace the shared buffer currently
used for printf, and repurposes the same hidden kernel argument. This
change introduces a new ValueKind in the HSA metadata to represent the
hostcall buffer.
Differential Revision: https://reviews.llvm.org/D70038
Summary of changes:
- added description of GFX10;
- added description of operands sccz, vccz, lds_direct, etc;
- minor bugfixing and improvements.
llvm-svn: 365347
Summary:
The directive defines a symbol as an group/local memory (LDS) symbol.
LDS symbols behave similar to common symbols for the purposes of ELF,
using the processor-specific SHN_AMDGPU_LDS as section index.
It is the linker and/or runtime loader's job to "instantiate" LDS symbols
and resolve relocations that reference them.
It is not possible to initialize LDS memory (not even zero-initialize
as for .bss).
We want to be able to link together objects -- starting with relocatable
objects, but possible expanding to shared objects in the future -- that
access LDS memory in a flexible way.
LDS memory is in an address space that is entirely separate from the
address space that contains the program image (code and normal data),
so having program segments for it doesn't really make sense.
Furthermore, we want to be able to compile multiple kernels in a
compilation unit which have disjoint use of LDS memory. In that case,
we may want to place LDS symbols differently for different kernels
to save memory (LDS memory is very limited and physically private to
each kernel invocation), so we can't simply place LDS symbols in a
.lds section.
Hence this solution where LDS symbols always stay undefined.
Change-Id: I08cbc37a7c0c32f53f7b6123aa0afc91dbc1748f
Reviewers: arsenm, rampitec, t-tye, b-sumner, jsjodin
Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, rupprecht, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61493
llvm-svn: 364296
Since this can be set with s_setreg*, it should not be a subtarget
property. Set a default based on the calling convention, and Introduce
a new amdgpu-dx10-clamp attribute to override this if desired.
Also introduce a new amdgpu-ieee attribute to match.
The values need to match to allow inlining. I think it is OK for the
caller's dx10-clamp attribute to override the callee, but there
doesn't appear to be the infrastructure to do this currently without
definining the attribute in the generic Attributes.td.
Eventually the calling convention lowering will need to insert a mode
switch somewhere for these.
llvm-svn: 357302
Document the intended use of the `.amdgcn.next_free_{s,v}gpr` in the
context of multiple kernels and functions.
Differential Revision: https://reviews.llvm.org/D59949
llvm-svn: 357289
Ensure Code Object V2 documentation is complete, but always contains a
warning and a link to the equivalent Code Object V3 documentation.
Explicitly indicate that any note records present in a code object that
are not documented must be considered deprecated and ignored.
Differential Revision: https://reviews.llvm.org/D59782
llvm-svn: 357176
Add an experimental buffer fat pointer address space that is currently
unhandled in the backend. This commit reserves address space 7 as a
non-integral pointer repsenting the 160-bit fat pointer (128-bit buffer
descriptor + 32-bit offset) that is heavily used in graphics workloads
using the AMDGPU backend.
Differential Revision: https://reviews.llvm.org/D58957
llvm-svn: 356373
Tony