After outputting block scalar string, the indent will be wrong.
This patch fixes Padding after block scalar string to ensure the correct
format of yaml.
The new added ut will fail in main.
```diff
@@ -3,4 +3,4 @@
Just a block
scalar doc
-scalar: a
+ scalar: a
...\n
```
The CWSR trap handler needs to save and restore the VGPRs. When dynamic
VGPRs are in use, the fixed function hardware will only allocate enough
space for one VGPR block. The rest will have to be stored in scratch, at
offset 0.
This patch allocates the necessary space by:
- generating a prologue that checks at runtime if we're on a compute
queue (since CWSR only works on compute queues); for this we will have
to check the ME_ID bits of the ID_HW_ID2 register - if that is non-zero,
we can assume we're on a compute queue and initialize the SP and FP with
enough room for the dynamic VGPRs
- forcing all compute entry functions to use a FP so they can access
their locals/spills correctly (this isn't ideal but it's the quickest to
implement)
Note that at the moment we allocate enough space for the theoretical
maximum number of VGPRs that can be allocated dynamically (for blocks of
16 registers, this will be 128, of which we subtract the first 16, which
are already allocated by the fixed function hardware). Future patches
may decide to allocate less if they can prove the shader never allocates
that many blocks.
Also note that this should not affect any reported stack sizes (e.g. PAL
backend_stack_size etc).
andorbitset.ll is interesting since it directly depends on the
difference between poison and undef. Not sure it's useful to keep
the version using poison, I assume none of this code makes it to
codegen.
si-spill-cf.ll was also a nasty case, which I doubt has been reproducing
its original issue for a very long time. I had to reclaim an older version,
replace some of the poison uses, and run simplify-cfg. There's a very
slight change in the final CFG with this, but final the output is approximately
the same as it used to be.
EnableTailMerge is false by default and is handled by the pass builder.
Passes are independent of target pipeline options.
This completes the generic `MachineLateOptimization` passes for the NPM
pipeline.
This PR updates the SGPR layout to a striped caller/callee-saved design,
similar
to the VGPR layout.
To ensure that s30-s31 (return address), s32 (stack pointer), s33 (frame
pointer), and s34 (base pointer) remain callee-saved, the striped layout
starts
from s40, with a stripe width of 8. The last stripe is 10 wide instead
of 8 to
avoid ending with a 2-wide stripe.
Fixes#113782.
Use `-passes="regallocgreedy<[all|sgpr|wwm|vgpr]>` to insert the greedy
RA with a filter and `-regalloc-npm=<type>` to control which RA to use
in existing pipeline.
This change fold together the _ari, _ari64, and _asi variants of these
instructions into a single instruction capable of holding any address.
This allows for the removal of a lot of unnecessary code and moves us
towards a standard way of representing an address in NVPTX.
Remove load and store instructions which do not include an immediate,
and just use the immediate variants in all cases. These variants will be
emitted exactly the same when the immediate offset is 0. Removing the
non-immediate versions allows for the removal of a lot of code and would
make any MachineIR passes simpler.
llvm/llvm-project@9e436c2daa tries to handle register masks and
sub-registers, it avoids clobbering RegUnit presreved by regmask. But it
then introduces invalid pointer issues.
We delete the copies without invalidate all the use in the CopyInfo, so
we dereferenced invalid pointers in next interation, causing asserts.
Fixes: #126107
---------
Co-authored-by: Matt Arsenault <arsenm2@gmail.com>
This patch contains a number of changes relating to the above flag;
primarily it updates comment references to the old flag names,
"-fextend-lifetimes" and "-fextend-this-ptr" to refer to the new names,
"-fextend-variable-liveness[={all,this}]". These changes are all NFC.
This patch also removes the explicit -fextend-this-ptr-liveness flag
alias, and shortens the help-text for the main flag; these are both
changes that were meant to be applied in the initial PR (#110000), but
due to some user-error on my part they were not included in the merged
commit.
Occupancy (i.e., the number of waves per EU) depends, in addition to
register usage, on per-workgroup LDS usage as well as on the range of
possible workgroup sizes. Mirroring the latter, occupancy should
therefore be expressed as a range since different group sizes generally
yield different achievable occupancies.
`getOccupancyWithLocalMemSize` currently returns a scalar occupancy
based on the maximum workgroup size and LDS usage. With respect to the
workgroup size range, this scalar can be the minimum, the maximum, or
neither of the two of the range of achievable occupancies. This commit
fixes the function by making it compute and return the range of
achievable occupancies w.r.t. workgroup size and LDS usage; it also
renames it to `getOccupancyWithWorkGroupSizes` since it is the range of
workgroup sizes that produces the range of achievable occupancies.
Computing the achievable occupancy range is surprisingly involved.
Minimum/maximum workgroup sizes do not necessarily yield maximum/minimum
occupancies i.e., sometimes workgroup sizes inside the range yield the
occupancy bounds. The implementation finds these sizes in constant time;
heavy documentation explains the rationale behind the sometimes
relatively obscure calculations.
As a justifying example, consider a target with 10 waves / EU, 4 EUs/CU,
64-wide waves. Also consider a function with no LDS usage and a flat
workgroup size range of [513,1024].
- A group of 513 items requires 9 waves per group. Only 4 groups made up
of 9 waves each can fit fully on a CU at any given time, for a total of
36 waves on the CU, or 9 per EU. However, filling as much as possible
the remaining 40-36=4 wave slots without decreasing the number of groups
reveals that a larger group of 640 items yields 40 waves on the CU, or
10 per EU.
- Similarly, a group of 1024 items requires 16 waves per group. Only 2
groups made up of 16 waves each can fit fully on a CU ay any given time,
for a total of 32 waves on the CU, or 8 per EU. However, removing as
many waves as possible from the groups without being able to fit another
equal-sized group on the CU reveals that a smaller group of 896 items
yields 28 waves on the CU, or 7 per EU.
Therefore the achievable occupancy range for this function is not [8,9]
as the group size bounds directly yield, but [7,10].
Naturally this change causes a lot of test churn as instruction
scheduling is driven by achievable occupancy estimates. In most unit
tests the flat workgroup size range is the default [1,1024] which,
ignoring potential LDS limitations, would previously produce a scalar
occupancy of 8 (derived from 1024) on a lot of targets, whereas we now
consider the maximum occupancy to be 10 in such cases. Most tests are
updated automatically and checked manually for sanity. I also manually
changed some non-automatically generated assertions when necessary.
Fixes#118220.
This change implements import call optimization for AArch64 Windows
(equivalent to the undocumented MSVC `/d2ImportCallOptimization` flag).
Import call optimization adds additional data to the binary which can be
used by the Windows kernel loader to rewrite indirect calls to imported
functions as direct calls. It uses the same [Dynamic Value Relocation
Table mechanism that was leveraged on x64 to implement
`/d2GuardRetpoline`](https://techcommunity.microsoft.com/blog/windowsosplatform/mitigating-spectre-variant-2-with-retpoline-on-windows/295618).
The change to the obj file is to add a new `.impcall` section with the
following layout:
```cpp
// Per section that contains calls to imported functions:
// uint32_t SectionSize: Size in bytes for information in this section.
// uint32_t Section Number
// Per call to imported function in section:
// uint32_t Kind: the kind of imported function.
// uint32_t BranchOffset: the offset of the branch instruction in its
// parent section.
// uint32_t TargetSymbolId: the symbol id of the called function.
```
NOTE: If the import call optimization feature is enabled, then the
`.impcall` section must be emitted, even if there are no calls to
imported functions.
The implementation is split across a few parts of LLVM:
* During AArch64 instruction selection, the `GlobalValue` for each call
to a global is recorded into the Extra Information for that node.
* During lowering to machine instructions, the called global value for
each call is noted in its containing `MachineFunction`.
* During AArch64 asm printing, if the import call optimization feature
is enabled:
- A (new) `.impcall` directive is emitted for each call to an imported
function.
- The `.impcall` section is emitted with its magic header (but is not
filled in).
* During COFF object writing, the `.impcall` section is filled in based
on each `.impcall` directive that were encountered.
The `.impcall` section can only be filled in when we are writing the
COFF object as it requires the actual section numbers, which are only
assigned at that point (i.e., they don't exist during asm printing).
I had tried to avoid using the Extra Information during instruction
selection and instead implement this either purely during asm printing
or in a `MachineFunctionPass` (as suggested in [on the
forums](https://discourse.llvm.org/t/design-gathering-locations-of-instructions-to-emit-into-a-section/83729/3))
but this was not possible due to how loading and calling an imported
function works on AArch64. Specifically, they are emitted as `ADRP` +
`LDR` (to load the symbol) then a `BR` (to do the call), so at the point
when we have machine instructions, we would have to work backwards
through the instructions to discover what is being called. An initial
prototype did work by inspecting instructions; however, it didn't
correctly handle the case where the same function was called twice in a
row, which caused LLVM to elide the `ADRP` + `LDR` and reuse the
previously loaded address. Worse than that, sometimes for the
double-call case LLVM decided to spill the loaded address to the stack
and then reload it before making the second call. So, instead of trying
to implement logic to discover where the value in a register came from,
I instead recorded the symbol being called at the last place where it
was easy to do: instruction selection.
As part #112171, support for FEAT_PAuthLR's CFI instructions was added.
However, the CFI instructions are emitted in the incorrect location. This
leads to incorrect CodeGen being generated and possible issues when
running a program. According to the ABI, the CFI instructions should be
emitted before the signing instruction. This is now done properly.
ABI information can be found here:
bf0e2c8047/aadwarf64/aadwarf64.rst (44call-frame-instructions)
Similar to 806761a7629df268c8aed49657aeccffa6bca449
-mtriple= specifies the full target triple while -march= merely sets the
architecture part of the default target triple (e.g. Windows, macOS).
Therefore, -march= is error-prone and not recommended for tests without
a target triple. The issue has been benign as these MIR tests do not
utilize object file format specific detail, but it's good to change
these tests to neighbor files that use -mtriple=x86_64
Similar to 806761a7629df268c8aed49657aeccffa6bca449
-mtriple= specifies the full target triple while -march= merely sets the
architecture part of the default target triple (e.g. Windows, macOS),
leaving a target triple which may not make sense.
Therefore, -march= is error-prone and not recommended for tests without
a target triple. The issue has been benign as we recognize
nvptx{,64}-apple-darwin as ELF instead of rejecting it outrightly.
Similar to 806761a7629df268c8aed49657aeccffa6bca449
-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.
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.
The MIRPrinter emits ` :: ` at the start of a MMO. The MIRLexer eats all
the white space after the operand and before the `::` when there is no
comment. We need to eat the space after the comment to allow MIRLexer to
parse comments on a MMO.
As part of FEAT_PAuthLR, a new DWARF Frame Instruction was introduced,
`DW_CFA_AARCH64_negate_ra_state_with_pc`. This instructs Libunwind that
the PC has been used with the signing instruction. This change includes
three commits
- Libunwind support for the newly introduced DWARF Instruction
- CodeGen Support for the DWARF Instructions
- Reversing the changes made in #96377. Due to
`DW_CFA_AARCH64_negate_ra_state_with_pc`'s requirements to be placed
immediately after the signing instruction, this would mean the CFI
Instruction location was not consistent with the generated location when
not using FEAT_PAuthLR. The commit reverses the changes and makes the
location consistent across the different branch protection options.
While this does have a code size effect, this is a negligible one.
For the ABI information, see here:
853286c7ab/aadwarf64/aadwarf64.rst (id23)
[MIR] Serialize virtual register flags
This introduces target-specific vreg flag serialization. Flags are represented as `uint8_t` and the `TargetRegisterInfo` override provides methods `getVRegFlagValue` to deserialize and `getVRegFlagsOfReg` to serialize.
Following the addition of the llvm.fake.use intrinsic and corresponding
MIR instruction, two further changes are planned: to add an
-fextend-lifetimes flag to Clang that emits these intrinsics, and to
have -Og enable this flag by default. Currently, some logic for handling
fake uses is gated by the optdebug attribute, which is intended to be
switched on by -fextend-lifetimes (and by extension -Og later on).
However, the decision was made that a general optdebug attribute should
be incompatible with other opt_ attributes (e.g. optsize, optnone),
since they all express different intents for how to optimize the
program. We would still like to allow -fextend-lifetimes with optsize
however (i.e. -Os -fextend-lifetimes should be legal), since it may be a
useful configuration and there is no technical reason to not allow it.
This patch resolves this by tracking MachineFunctions that have fake
uses, allowing us to run passes that interact with them and skip passes
that clash with them.
This fixes a test failure when expensive checks are enabled. Use the
correct return value when computing machine function properties resulted
in an error (e.g. when conflicting with explicitly set values).
Without this, the machine verifier would crash even in the presence of
parsing errors which should have gently terminated execution.
Allow setting the computed properties IsSSA, NoPHIs, NoVRegs for MIR
functions in MIR input. The default value is still the computed value.
If the property is set to false, the computed result is ignored. Conflicting
values (e.g. setting IsSSA where the input MIR is clearly not SSA) lead to
an error.
Closes#37787
Adds "initial" support for `syncscope` to the NVPTX backend
`load`/`store`/`fence` instructions.
Atomic Read-Modify-Write operations intentionally not supported as part
of this initial PR.
This patch does 3 things:
1. Add support for optimizing the address mode of HVX load/store
instructions
2. Reduce the value of Add instruction immediates by replacing with the
difference from other Addi instructions that share common base:
For Example, If we have the below sequence of instructions: r1 =
add(r2,# 1024) ... r3 = add(r2,# 1152) ... r4 = add(r2,# 1280)
Where the register r2 has the same reaching definition, They get
modified to the below sequence:
r1 = add(r2,# 1024)
...
r3 = add(r1,# 128)
...
r4 = add(r1,# 256)
3. Fixes a bug pass where the addi instructions were modified based on a
predicated register definition, leading to incorrect output.
Eg:
INST-1: if (p0) r2 = add(r13,# 128)
INST-2: r1 = add(r2,# 1024)
INST-3: r3 = add(r2,# 1152)
INST-4: r5 = add(r2,# 1280)
In the above case, since r2's definition is predicated, we do not want
to modify the uses of r2 in INST-3/INST-4 with add(r1,#128/256)
4.Fixes a corner case
It looks like we never check whether the offset register is actually
live (not clobbered) at optimization site. Add the check whether it is
live at MBB entrance. The rest should have already been verified.
5. Fixes a bad codegen
For whatever reason we do transformation without checking if the value
in register actually reaches the user. This is second identical fix for
this pass.
Co-authored-by: Anirudh Sundar <quic_sanirudh@quicinc.com>
Co-authored-by: Sergei Larin <slarin@quicinc.com>
This reverts commit
7792b4ae79.
The problem was a conflict with
e55d6f5ea2
"[AMDGPU] Simplify and improve codegen for llvm.amdgcn.set.inactive
(https://github.com/llvm/llvm-project/pull/107889)"
which changed the syntax of V_SET_INACTIVE (and thus made my MIR test
crash).
...if only we had a merge queue.
Reverts llvm/llvm-project#108173
si-init-whole-wave.mir crashes on some buildbots (although it passed
both locally with sanitizers enabled and in pre-merge tests).
Investigating.
