Before frame offsets are calculated, try to eliminate the
frame indexes used by SGPR spills. Then we can delete them
after.
I think for now we can be sure that no other instruction
will be re-using the same frame indexes. It should be easy
to notice if this assumption ever breaks since everything
asserts if it tries to use a dead frame index later.
The unused emergency stack slot seems to still be left behind,
so an additional 4 bytes is still wasted.
llvm-svn: 295753
Summary:
This lets you select which sort of spilling you want, either s[0:1] or 64-bit loads from s[0:1].
Patch By: Dave Airlie
Reviewers: nhaehnle, arsenm, tstellarAMD
Reviewed By: arsenm
Subscribers: mareko, llvm-commits, kzhuravl, wdng, yaxunl, tony-tye
Differential Revision: https://reviews.llvm.org/D25428
llvm-svn: 293000
It's possible to have a use of the private resource descriptor or
scratch wave offset registers even though there are no allocated
stack objects. This would result in continuing to use the maximum
number reserved registers. This could go over the number of SGPRs
available on VI, or violate the SGPR limit requested by
the function attributes.
llvm-svn: 285435
Summary:
mesa3d will use the same kernel calling convention as amdhsa, but it will
handle everything else like the default 'unknown' OS type.
Reviewers: arsenm
Subscribers: arsenm, llvm-commits, kzhuravl
Differential Revision: https://reviews.llvm.org/D22783
llvm-svn: 281779
- Implemented amdgpu-flat-work-group-size attribute
- Implemented amdgpu-num-active-waves-per-eu attribute
- Implemented amdgpu-num-sgpr attribute
- Implemented amdgpu-num-vgpr attribute
- Dynamic LDS constraints are in a separate patch
Patch by Tom Stellard and Konstantin Zhuravlyov
Differential Revision: https://reviews.llvm.org/D21562
llvm-svn: 280747
Debugger prologue is emitted if -mattr=+amdgpu-debugger-emit-prologue.
Debugger prologue writes work group IDs and work item IDs to scratch memory at fixed location in the following format:
- offset 0: work group ID x
- offset 4: work group ID y
- offset 8: work group ID z
- offset 16: work item ID x
- offset 20: work item ID y
- offset 24: work item ID z
Set
- amd_kernel_code_t::debug_wavefront_private_segment_offset_sgpr to scratch wave offset reg
- amd_kernel_code_t::debug_private_segment_buffer_sgpr to scratch rsrc reg
- amd_kernel_code_t::is_debug_supported to true if all debugger features are enabled
Differential Revision: http://reviews.llvm.org/D20335
llvm-svn: 273769
Split AMDGPUSubtarget into amdgcn/r600 specific subclasses.
This removes most of the static_casting of the basic codegen
classes everywhere, and tries to restrict the features
visible on the wrong target.
llvm-svn: 273652
[AMDGPU] emitPrologue looks for an unused unallocated SGPR that is not
the scratch descriptor. Continue search if unused register found fails
other requirements.
Reviewers: arsenm, tstellarAMD, nhaehnle
Subscribers: arsenm, llvm-commits, kzhuravl
Differential Revision: http://reviews.llvm.org/D20526
llvm-svn: 270646
Use register class that does not include them when looking
for unallocated registers.
This is hit by the udiv v8i64 test in the opencl integer
conformance test, and takes a few seconds to compile in
a debug build so no test included.
llvm-svn: 269938
Summary:
When there were no free SGPRs, we were trying to move this value into
some of the reserved registers which was causing a segmentation fault.
Reviewers: arsenm
Subscribers: arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D17590
llvm-svn: 262577
This was hardcoded to the static private size, but this
would be missing the offset and additional size for someday
when we have dynamic sizing.
Also stops always initializing flat_scratch even when unused.
In the future we should stop emitting this unless flat instructions
are used to access private memory. For example this will initialize
it almost always on VI because flat is used for global access.
llvm-svn: 260658
Due to the SGPR init bug, every program claims to use the same number
of SGPRs anyway, so there's no point in trying to shift those registers
down from their initial spot of reservation.
Add a test that uses VGPR spilling and blocks most SGPRs from being used for
the scratch resource register. Previously, this would run into an assertion.
Differential Revision: http://reviews.llvm.org/D15724
llvm-svn: 256870
If we know we have stack objects, we reserve the registers
that the private buffer resource and wave offset are passed
and use them directly.
If not, reserve the last 5 SGPRs just in case we need to spill.
After register allocation, try to pick the next available registers
instead of the last SGPRs, and then insert copies from the inputs
to the reserved registers in the progloue.
This also only selectively enables all of the input registers
which are really required instead of always enabling them.
llvm-svn: 254331
It does not work because of emergency stack slots.
This pass was supposed to eliminate dummy registers for the
spill instructions, but the register scavenger can introduce
more during PrologEpilogInserter, so some would end up
left behind if they were needed.
The potential for spilling the scratch resource descriptor
and offset register makes doing something like this
overly complicated. Reserve registers to use for the resource
descriptor and use them directly in eliminateFrameIndex.
Also removes creating another scratch resource descriptor
when directly selecting scratch MUBUF instructions.
The choice of which registers are reserved is temporary.
For now it attempts to pick the next available registers
after the user and system SGPRs.
llvm-svn: 254329
Matt Arsenault