buffer_load instructions that use TFE also need to zero initialize
return values similar to how the image instructions currently work. Add
support for this with standard zero init of all results + zero init of
just TFE flag when enable-prt-strict-null subtarget feature is disabled.
Update SIMemoryLegalizer and SIInsertWaitcnts to use separate wait
instructions per counter (e.g. S_WAIT_LOADCNT) and split VMCNT into
separate LOADCNT, SAMPLECNT and BVHCNT counters.
Similar to 806761a7629df268c8aed49657aeccffa6bca449.
For IR files without a target triple, -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,
e.g. amdgpu-apple-darwin.
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.
This patch changes AMDGPU tests to not rely on the default
OS/environment components. Tests that need fixes are not changed:
```
LLVM :: CodeGen/AMDGPU/fabs.f64.ll
LLVM :: CodeGen/AMDGPU/fabs.ll
LLVM :: CodeGen/AMDGPU/floor.ll
LLVM :: CodeGen/AMDGPU/fneg-fabs.f64.ll
LLVM :: CodeGen/AMDGPU/fneg-fabs.ll
LLVM :: CodeGen/AMDGPU/r600-infinite-loop-bug-while-reorganizing-vector.ll
LLVM :: CodeGen/AMDGPU/schedule-if-2.ll
```
SIInsertWaitcnts inserts waitcnt instructions to resolve data
dependencies. The GFX10+ vscnt (VMEM store count) counter is never used
in this way. It is only used to resolve memory dependencies, and that is
handled by SIMemoryLegalizer. Hence there is no need to conservatively
wait for vscnt to be 0 on function entry and before returns.
Differential Revision: https://reviews.llvm.org/D153537
This reverts commit ca907bfb57d8ad3ec3bcc2cff2abab7b1b933af6.
According to michel.daenzer,
> This completely broke the Mesa radeonsi driver on Navi 14. Xorg +
> xterm come up with major corruption & psychedelic colours.
When memory operations are outstanding on function calls, either the
caller or the callee can insert a waitcnt to ensure that all reads are
finished.
Calls need some time to be executed, so if the callee inserts the
waitcnt, filling the instruction buffer and waiting for memory will be
interleaved, hiding some latency. This comes at the cost of having a
waitcnt inside functions that may not be needed as no memory operations
are outstanding.
For function calls, this is already implemented. The same principal
applies to returns: If the caller inserts a waitcnt after the call, the
callee does not have to wait and the return and memory operation can be
run in parallel.
This commit implements waiting in the caller after returning from a
function call.
Differential Revision: https://reviews.llvm.org/D87674
Summary:
This commit adds new intrinsics
llvm.amdgcn.raw.buffer.load
llvm.amdgcn.raw.buffer.load.format
llvm.amdgcn.raw.buffer.load.format.d16
llvm.amdgcn.struct.buffer.load
llvm.amdgcn.struct.buffer.load.format
llvm.amdgcn.struct.buffer.load.format.d16
llvm.amdgcn.raw.buffer.store
llvm.amdgcn.raw.buffer.store.format
llvm.amdgcn.raw.buffer.store.format.d16
llvm.amdgcn.struct.buffer.store
llvm.amdgcn.struct.buffer.store.format
llvm.amdgcn.struct.buffer.store.format.d16
llvm.amdgcn.raw.buffer.atomic.*
llvm.amdgcn.struct.buffer.atomic.*
with the following changes from the llvm.amdgcn.buffer.*
intrinsics:
* there are separate raw and struct versions: raw does not have an
index arg and sets idxen=0 in the instruction, and struct always sets
idxen=1 in the instruction even if the index is 0, to allow for the
fact that gfx9 does bounds checking differently depending on whether
idxen is set;
* there is a combined cachepolicy arg (glc+slc)
* there are now only two offset args: one for the offset that is
included in bounds checking and swizzling, to be split between the
instruction's voffset and immoffset fields, and one for the offset
that is excluded from bounds checking and swizzling, to go into the
instruction's soffset field.
The AMDISD::BUFFER_* SD nodes always have an index operand, all three
offset operands, combined cachepolicy operand, and an extra idxen
operand.
The obsolescent llvm.amdgcn.buffer.* intrinsics continue to work.
Subscribers: arsenm, kzhuravl, wdng, nhaehnle, yaxunl, dstuttard, t-tye, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D50306
Change-Id: If897ea7dc34fcbf4d5496e98cc99a934f62fc205
llvm-svn: 340269
