Instructions on the transcendental unit are executed in parallel to the
normal VALU, so add this as an extra resource.
This doesn't seem to have any effect, but it should be more correct.
Differential Revision: https://reviews.llvm.org/D100123
Used to model structural hazards on FP issue, where some
instructions take up 2 issue slots and others one as well
as similar structural hazards on load issue, where some
instructions take up two load lanes and others one.
Differential Revision: https://reviews.llvm.org/D98977
The tests compare IPC statistics that MCA provides with IPC values
measured on Cortex-A55 hardware. For hardware tests, each snippet is
run in a loop unrolled by 1000, and IPC is measured by linux-perf.
Several tests do not match the hardware: the skewed ALU is not
supported, LDR seem to be missing a forwarding path.
Differential Revision: https://reviews.llvm.org/D98174
Instructions that have more uops than the processor's IssueWidth are
issued in multiple cycles.
The patch fixes PR49712.
Differential Revision: https://reviews.llvm.org/D99339
This is a follow-up for:
D98604 [MCA] Ensure that writes occur in-order
When instructions are aligned by the order of writes, they retire
in-order naturally. There is no need for an RCU, so it is disabled.
Differential Revision: https://reviews.llvm.org/D98628
Coyp SchedRW from pseudos to real instructions so that llvm-mca has
access to it. This is NFC for normal compiler codegen, which schedules
pseudos not real instructions.
Add an llvm-mca test for some high latency double-precision instructions
as a smoke test.
Differential Revision: https://reviews.llvm.org/D99187
Before this patch, register writes were always invalidated by the
RegisterFile at instruction commit stage. So,
the RegisterFile was often losing the knowledge about the `execute
cycle` of writes already committed. While this was not problematic
for non-delayed reads, this was sometimes leading to inaccurate read
latency computations in the presence of negative read-advance cycles.
This patch fixes the issue by changing how the RegisterFile component
internally keeps track of the `execute cycle` information of each
write. On every instruction executed, the RegisterFile gets notified
by the RetireStage, so that it can internally record the execute
cycle of each executed write.
The `execute cycle` information is stored within WriteRef itself, and
it is not invalidated when the write is committed.
This patch adds a pipeline to support in-order CPUs such as ARM
Cortex-A55.
In-order pipeline implements a simplified version of Dispatch,
Scheduler and Execute stages as a single stage. Entry and Retire
stages are common for both in-order and out-of-order pipelines.
Differential Revision: https://reviews.llvm.org/D94928
On z/OS, the following error message is not matched correctly in lit tests.
```
EDC5129I No such file or directory.
```
This patch uses a lit config substitution to check for platform specific error messages.
Reviewed By: muiez, jhenderson
Differential Revision: https://reviews.llvm.org/D95246
On z/OS, the following error message is not matched correctly in lit tests. This patch updates the CHECK expression to match successfully.
```
EDC5129I No such file or directory.
```
Reviewed By: muiez
Differential Revision: https://reviews.llvm.org/D94239
The old CPU model only had MLA->MLA forwarding. I added some missing
MUL->MLA read advances and a missing absolute diff accumulator read
advance according to the Cortex A57 Software Optimization Guide.
The patch improves performance in EEMBC rgbyiqv2 by about 6%-7% and
spec2006/milc by 8% (repeated runs on multiple devices), causes no
significant regressions (none in SPEC).
Differential Revision: https://reviews.llvm.org/D92296
These properties aren't additive. They are closer to ReadOnly and
WriteOnly. The default is ReadWrite. ReadMem cancels the write property and
WriteMem cancels the read property. Combining them leaves neither.
This patch checks that when we process WriteMem, the Mod flag is
still set. And for ReadMem we check that the Ref flag set still set.
I've updated 2 target intrinsics that were combining these properties.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D93571
These instructions read their inputs from fixed registers rather
than using a modrm byte. We shouldn't require the user to list them
when parsing assembly. This matches the GNU assembler.
This patch adds InstAliases so we can accept either form. It also
changes the printing code to use the form without registers. This
will change the behavior of llvm-objdump, but should be consistent
with binutils objdump. This also matches what we already do in LLVM for
clzero and monitorx which also used fixed registers.
I need to add and improve tests before this can be commited. The
disassembler tests exist, but weren't checking the fixed register
so they pass before and after this change.
Fixes https://github.com/ClangBuiltLinux/linux/issues/1216
Differential Revision: https://reviews.llvm.org/D93524
The model was committed in 4b8ade837e
but not yet enabled to allow for a few fix ups. This adds a few
of these fixes, and also a LLVM MCA test to check most instructions.
While I do have plans to look into some more tuning, it's time to
enable this as it better than using the A53 schedule.
Differential Revision: https://reviews.llvm.org/D88017
Patch fixes scheduling of ALU instructions which modify pc register. Patch
also fixes computation of mutually exclusive predicates for sequences of
variants to be properly expanded
Differential revision: https://reviews.llvm.org/D91266
This patch adds the SchedMachineModel for Cortex-M7. It
also adds test cases for the scheduling information.
Details of the pipeline and descriptions are in comments
in file ARMScheduleM7.td included in this patch.
Differential Revision: https://reviews.llvm.org/D91355
Patch fixes case when sched class has write and read variants belonging
to different processor models.
Differential revision: https://reviews.llvm.org/D89777
Only the aliases 'xzr' and 'sp' exist for the physical register x31.
The reason for wanting to remove the alias 'x31' is because it allows users
to write invalid asm that is not accepted by the GNU assembler.
Is there any objection to removing this alias? Or do we want to keep
this for compatibility with existing code that uses w31/x31?
Differential Revision: https://reviews.llvm.org/D90153
This is likely to be a regressigion introduced by my last refactoring of the
LSUnit (commit 5578ec32f9). Before this patch, the
"CurrentStoreBarrierGroupID" index was not correctly reset on store barrier
executions. This was leading to unexpected crashes like the one reported as
PR48024.
Sebastian Neubauer