26 Commits

Author SHA1 Message Date
Johannes Doerfert
477e8e10f0 [Attributor] Teach AAPointerInfo to look into aggregates
If we have a constant aggregate, e.g., as an initializer, we usually
failed to extract the proper value/type from it. This patch provides the
size and offset information necessary to extract the right part of the
constant.
2022-10-05 06:19:47 -07:00
Johannes Doerfert
c922cac868 Revert "[Attributor] AAPointerInfo should allow "harmless" uses"
Revert "[Attributor] Teach AAPointerInfo to look into aggregates"

This reverts commit 844f6c5d03d58e7ac0c6b838e4a7834ac575ab9b and
4ed0a88cd8a77370073feb270d77a9e8b27bd68c as they broke the buildbots
that run openmp/libomptarget/test/offloading/bug49021.cpp.
2022-09-11 21:37:54 -07:00
Johannes Doerfert
4ed0a88cd8 [Attributor] Teach AAPointerInfo to look into aggregates
If we have a constant aggregate, e.g., as an initializer, we usually
failed to extract the proper value/type from it. This patch provides the
size and offset information necessary to extract the right part of the
constant.
2022-09-11 20:16:11 -07:00
Johannes Doerfert
bf789b1957 [Attributor] Replace AAValueSimplify with AAPotentialValues
For the longest time we used `AAValueSimplify` and
`genericValueTraversal` to determine "potential values". This was
problematic for many reasons:
- We recomputed the result a lot as there was no caching for the 9
  locations calling `genericValueTraversal`.
- We added the idea of "intra" vs. "inter" procedural simplification
  only as an afterthought. `genericValueTraversal` did offer an option
  but `AAValueSimplify` did not. Thus, we might end up with "too much"
  simplification in certain situations and then gave up on it.
- Because `genericValueTraversal` was not a real `AA` we ended up with
  problems like the infinite recursion bug (#54981) as well as code
  duplication.

This patch introduces `AAPotentialValues` and replaces the
`AAValueSimplify` uses with it. `genericValueTraversal` is folded into
`AAPotentialValues` as are the instruction simplifications performed in
`AAValueSimplify` before. We further distinguish "intra" and "inter"
procedural simplification now.

`AAValueSimplify` was not deleted as we haven't ported the
re-materialization of instructions yet. There are other differences over
the former handling, e.g., we may not fold trivially foldable
instructions right now, e.g., `add i32 1, 1` is not folded to `i32 2`
but if an operand would be simplified to `i32 1` we would fold it still.

We are also even more aware of function/SCC boundaries in CGSCC passes,
which is good even if some tests look like they regress.

Fixes: https://github.com/llvm/llvm-project/issues/54981

Note: A previous version was flawed and consequently reverted in
      6555558a80589d1c5a1154b92cc3af9495f8f86c.
2022-07-19 16:24:42 -05:00
Jon Chesterfield
3a20597776 [amdgpu] Implement lds kernel id intrinsic
Implement an intrinsic for use lowering LDS variables to different
addresses from different kernels. This will allow kernels that cannot
reach an LDS variable to avoid wasting space for it.

There are a number of implicit arguments accessed by intrinsic already
so this implementation closely follows the existing handling. It is slightly
novel in that this SGPR is written by the kernel prologue.

It is necessary in the general case to put variables at different addresses
such that they can be compactly allocated and thus necessary for an
indirect function call to have some means of determining where a
given variable was allocated. Claiming an arbitrary SGPR into which
an integer can be written by the kernel, in this implementation based
on metadata associated with that kernel, which is then passed on to
indirect call sites is sufficient to determine the variable address.

The intent is to emit a __const array of LDS addresses and index into it.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D125060
2022-07-19 17:46:19 +01:00
Johannes Doerfert
3be3b40188 [Attributor][NFCI] Introduce AttributorConfig to bundle all options
Instead of lengthy constructors we can now set the members of a
read-only struct before the Attributor is created. Should make it
clearer what is configurable and also help introducing new options in
the future. This actually added IsModulePass and avoids deduction
through the Function set size. No functional change was intended.
2022-04-15 18:17:19 -05:00
Changpeng Fang
8edaf25986 AMDGPU: Emit metadata for the hidden_multigrid_sync_arg conditionally
Summary:
  Introduce a new function attribute, amdgpu-no-multigrid-sync-arg, which is default.
We use implicitarg_ptr + offset to check whether the multigrid synchronization
pointer is used. If yes, we remove this attribute and also remove
amdgpu-no-implicitarg-ptr. We generate metadata for the hidden_multigrid_sync_arg
only when the amdgpu-no-multigrid-sync-arg attribute is removed from the function.

Reviewers: arsenm, sameerds, b-sumner and foad

Differential Revision: https://reviews.llvm.org/D123548
2022-04-12 12:36:30 -07:00
Changpeng Fang
dd5895cc39 AMDGPU: Use the implicit kernargs for code object version 5
Summary:
  Specifically, for trap handling, for targets that do not support getDoorbellID,
we load the queue_ptr from the implicit kernarg, and move queue_ptr to s[0:1].
To get aperture bases when targets do not have aperture registers, we load
private_base or shared_base directly from the implicit kernarg. In clang, we use
implicitarg_ptr + offsets to implement __builtin_amdgcn_workgroup_size_{xyz}.

Reviewers: arsenm, sameerds, yaxunl

Differential Revision: https://reviews.llvm.org/D120265
2022-03-17 14:12:36 -07:00
Changpeng Fang
0f20a35b9e AMDGPU: Set up User SGPRs for queue_ptr only when necessary
Summary:
  In general, we need queue_ptr for aperture bases and trap handling,
and user SGPRs have to be set up to hold queue_ptr. In current implementation,
user SGPRs are set up unnecessarily for some cases. If the target has aperture
registers, queue_ptr is not needed to reference aperture bases. For trap
handling, if target suppots getDoorbellID, queue_ptr is also not necessary.
Futher, code object version 5 introduces new kernel ABI which passes queue_ptr
as an implicit kernel argument, so user SGPRs are no longer necessary for
queue_ptr. Based on the trap handling document:
https://llvm.org/docs/AMDGPUUsage.html#amdgpu-trap-handler-for-amdhsa-os-v4-onwards-table,
llvm.debugtrap does not need queue_ptr, we remove queue_ptr suport for llvm.debugtrap
in the backend.

Reviewers: sameerds, arsenm

Fixes: SWDEV-307189

Differential Revision: https://reviews.llvm.org/D119762
2022-03-09 10:14:05 -08:00
Changpeng Fang
ca62b1db9f [AMDGPU][NFC]: Emit metadata for hidden_heap_v1 kernarg
Summary:
  Emit metadata for hidden_heap_v1 kernarg

Reviewers:
  sameerds, b-sumner

Fixes:
  SWDEV-307188

Differential Revision:
  https://reviews.llvm.org/D119027
2022-02-25 10:45:35 -08:00
Sameer Sahasrabuddhe
d8f99bb6e0 [AMDGPU] replace hostcall module flag with function attribute
The module flag to indicate use of hostcall is insufficient to catch
all cases where hostcall might be in use by a kernel. This is now
replaced by a function attribute that gets propagated to top-level
kernel functions via their respective call-graph.

If the attribute "amdgpu-no-hostcall-ptr" is absent on a kernel, the
default behaviour is to emit kernel metadata indicating that the
kernel uses the hostcall buffer pointer passed as an implicit
argument.

The attribute may be placed explicitly by the user, or inferred by the
AMDGPU attributor by examining the call-graph. The attribute is
inferred only if the function is not being sanitized, and the
implictarg_ptr does not result in a load of any byte in the hostcall
pointer argument.

Reviewed By: jdoerfert, arsenm, kpyzhov

Differential Revision: https://reviews.llvm.org/D119216
2022-02-11 22:51:56 +05:30
Sameer Sahasrabuddhe
c6a6b57902 [AMDGPU] [NFC] Fix incorrect use of bitwise operator.
Differential Revision: https://reviews.llvm.org/D119308
2022-02-08 22:12:54 -05:00
Sameer Sahasrabuddhe
02a2e46ff0 [AMDGPU] [NFC] refactor the AMDGPU attributor
Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D119087
2022-02-07 21:45:32 -05:00
Matt Arsenault
4132dc917e AMDGPU: Return result from indicatePessimisticFixpoint
I don't think this fixes anything.
2021-12-16 11:26:30 -05:00
Matt Arsenault
6bcf1f9181 AMDGPU: Indicate pessimistic fixpoint for entry functions
There aren't going to be any callers for these, so avoid running
through the machinery to look at the callers.
2021-12-11 11:42:34 -05:00
Matt Arsenault
0eebe2e36c AMDGPU: Sanitized functions require implicit arguments
Do not infer no-amdgpu-implicitarg-ptr for sanitized functions. If a
function is explicitly marked amdgpu-no-implicitarg-ptr and
sanitize_address, infer that it is required.
2021-12-02 17:55:43 -05:00
Benjamin Kramer
9b8b16457c Put implementation details into anonymous namespaces. NFCI. 2021-11-07 15:18:30 +01:00
Matt Arsenault
ec57b37551 AMDGPU: Use attributor to propagate amdgpu-flat-work-group-size
This can merge the acceptable ranges based on the call graph, rather
than the simple application of the attribute. Remove the handling from
the old pass.
2021-10-22 16:23:50 -04:00
Matt Arsenault
f12174204c AMDGPU: Rename attributor class for uniform-work-group-size
This isn't really an AMDGPU specific attribute and could be moved to
generic code. It's also important to include the word uniform in the
name.
2021-09-14 19:49:08 -04:00
Matt Arsenault
088cc63640 AMDGPU: Invert AMDGPUAttributor
Switch to using BitIntegerState for each of the inputs, and invert
their meanings.

This now diverges more from the old AMDGPUAnnotateKernelFeatures, but
this isn't used yet anyway.
2021-08-26 21:32:13 -04:00
Matt Arsenault
46d82e7357 AMDGPU: Restrict attributor transforms
We only really want this to add the custom attributes. Theoretically
the regular transforms were already run at this point. Touching
undefined behavior breaks a lot of tests when this is enabled by
default, many of which are expecting to test handling of undef
operations.
2021-08-26 21:08:51 -04:00
Matt Arsenault
cf32d61a05 AMDGPU: Remove hacky attribute deduction from AMDGPUAttributor
amdgpu-calls and amdgpu-stack-objects don't really belong as
attributes, and are currently a hacky way of passing an analysis into
the DAG. These don't really belong in the IR, and don't really fit in
with the other attributes. Remove these to facilitate inverting the
pass.

I don't exactly understand the indirect call test changes. These tests
are using calls which are trivially replacable with a direct call, so
I'm not sure what the point is.
2021-08-26 20:31:14 -04:00
Matt Arsenault
98d7aa435f AMDGPU: Stop inferring use of llvm.amdgcn.kernarg.segment.ptr
We no longer use this intrinsic outside of the backend and no longer
support using it outside of kernels.
2021-08-26 20:30:03 -04:00
Matt Arsenault
a77ae4aa6a AMDGPU: Stop attributor adding attributes to intrinsic declarations 2021-08-13 20:51:48 -04:00
Alexander Belyaev
edb05d555e [llvm] Inline getAssociatedFunction() in LLVM_DEBUG.
Function* F is used only inside LLVM_DEBUG, so that it causes unused
variable warning.
2021-07-24 11:49:21 +02:00
Kuter Dinel
96709823ec [AMDGPU] Deduce attributes with the Attributor
This patch introduces a pass that uses the Attributor to deduce AMDGPU specific attributes.

Reviewed By: jdoerfert, arsenm

Differential Revision: https://reviews.llvm.org/D104997
2021-07-24 06:07:15 +03:00