Commit Graph

13 Commits

Author SHA1 Message Date
Joe Nash 3ce1b9631a [AMDGPU] Switch PostRA sched to MachineSched
Use GCNHazardRecognizer in postra sched.
Updated tests for the new schedules.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D109536

Change-Id: Ia86ba2ae168f12fb34b4d8efdab491f84d936cde
2021-09-14 15:11:27 -04:00
Matt Arsenault 722b8e0e5a AMDGPU: Invert ABI attribute handling
Previously we assumed all callable functions did not need any
implicitly passed inputs, and added attributes to functions to
indicate when they were necessary. Requiring attributes for
correctness is pretty ugly, and it makes supporting indirect and
external calls more complicated.

This inverts the direction of the attributes, so an undecorated
function is assumed to need all implicit imputs. This enables
AMDGPUAttributor by default to mark when functions are proven to not
need a given input. This strips the equivalent functionality from the
legacy AMDGPUAnnotateKernelFeatures pass.

However, AMDGPUAnnotateKernelFeatures is not fully removed at this
point although it should be in the future. It is still necessary for
the two hacky amdgpu-calls and amdgpu-stack-objects attributes, which
would be better served by a trivial analysis on the IR during
selection. Additionally, AMDGPUAnnotateKernelFeatures still
redundantly handles the uniform-work-group-size attribute to be
removed in a future commit.

At this point when not using -amdgpu-fixed-function-abi, we are still
modifying the ABI based on these newly negated attributes. In the
future, this option will be removed and the locations for implicit
inputs will always be fixed. We will then use the new attributes to
avoid passing the values when unnecessary.
2021-09-09 18:24:28 -04:00
Sebastian Neubauer 4359b870b1 [AMDGPU] Init scratch only if necessary
If no scratch or flat instructions are used, we do not need to
initialize the flat scratch hardware register.

Differential Revision: https://reviews.llvm.org/D105920
2021-07-14 10:45:22 +02:00
Sebastian Neubauer 96e1fcb1e0 [AMDGPU] Use s_add_i32 for address additions
This allows to convert the add instruction to s_addk_i32 and
v_add_nc_u32 instead of needing v_add_co_u32 when converting to a VALU
instruction.

Differential Revision: https://reviews.llvm.org/D103322
2021-06-07 16:09:48 +02:00
madhur13490 5682ae2fc6 [AMDGPU] Set implicit arg attributes for indirect calls
This patch adds attributes corresponding to
implicits to functions/kernels if
1. it has an indirect call OR
2. it's address is taken.

Once such attributes are set, rest of the codegen would work
out-of-box for indirect calls. This patch eliminates
the potential overhead -fixed-abi imposes even though indirect functions
calls are not used.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D99347
2021-04-13 13:15:13 +00:00
madhur13490 3c297a2564 Make fixed-abi default for AMD HSA OS
fixed-abi uses pre-defined and predictable
SGPR/VGPRs for passing arguments. This patch makes
this scheme default when HSA OS is specified in triple.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D96340
2021-02-19 15:05:25 +00:00
Tony 2f499b9aff [AMDGPU] Add volatile support to SIMemoryLegalizer
Treat a non-atomic volatile load and store as a relaxed atomic at
system scope for the address spaces accessed. This will ensure all
relevant caches will be bypassed.

A volatile atomic is not changed and still only bypasses caches upto
the level specified by the SyncScope operand.

Differential Revision: https://reviews.llvm.org/D94214
2021-01-09 00:52:33 +00:00
Jay Foad d28624a209 [AMDGPU] Stop adding an implicit def of vcc_hi for wave32
This doesn't seem to be needed for anything.

Differential Revision: https://reviews.llvm.org/D92400
2020-12-02 10:11:42 +00:00
Jay Foad 4bdab2e86a [AMDGPU] Fix offset for REL32_HI relocs
The addend in a REL32 reloc needs to be adjusted to account for the
offset from the PC value returned by the s_getpc instruction to the
point where the reloc is applied. This was being done correctly for
(GOTPC)REL32_LO but not for (GOTPC)REL32_HI. This will only make a
difference if the target symbol happens to get loaded almost exactly
a multiple of 4G away from the relocated instructions.

Differential Revision: https://reviews.llvm.org/D86938
2020-09-02 10:55:55 +01:00
Carl Ritson 5bf2a9dd40 [AMDGPU] Update VMEM scalar write hazard mitigation sequence
Using s_waitcnt_depctr 0xffe3 is potentially faster than v_nop.

Reviewed By: rampitec, foad

Differential Revision: https://reviews.llvm.org/D83872
2020-07-16 11:37:45 +09:00
Jay Foad 590964c835 [AMDGPU] More accurate gfx10 latencies
Differential Revision: https://reviews.llvm.org/D81012
2020-06-04 10:29:32 +01:00
Scott Linder 0e9368cc8c [AMDGPU] Move frame pointer from s34 to s33
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
2020-03-19 15:35:16 -04:00
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