The code reusing existing wait counts is incorrect since it keeps
adding new operands to an old instruction instead of replacing
the immediate. It was also effectively switched off by the condition
that wait count is not an AMDGPU::S_WAITCNT.
Also switched to BuildMI instead of creating instructions directly.
Differential Revision: https://reviews.llvm.org/D42997
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@324547 91177308-0d34-0410-b5e6-96231b3b80d8
1. Run the memory legalizer prior to the waitcnt pass; keep the policy that the waitcnt pass does not remove any waitcnts within the incoming IR.
2. The waitcnt pass doesn't (yet) track waitcnts that exist prior to the waitcnt pass (it just skips over them); because the waitcnt pass is ignorant of them, it may insert a redundant waitcnt. To avoid this, check the prev instr. If it and the to-be-inserted waitcnt are the same, suppress the insertion. We keep the existing waitcnt under the assumption that whomever, e.g., the memory legalizer, inserted it knows what they were doing.
3. Follow-on work: teach the waitcnt pass to record the pre-existing waitcnts for better waitcnt production.
Differential Revision: https://reviews.llvm.org/D42854
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@324440 91177308-0d34-0410-b5e6-96231b3b80d8
-amdgpu-waitcnt-forcezero={1|0} Force all waitcnt instrs to be emitted as s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
-amdgpu-waitcnt-forceexp=<n> Force emit a s_waitcnt expcnt(0) before the first <n> instrs
-amdgpu-waitcnt-forcelgkm=<n> Force emit a s_waitcnt lgkmcnt(0) before the first <n> instrs
-amdgpu-waitcnt-forcevm=<n> Force emit a s_waitcnt vmcnt(0) before the first <n> instrs
This patch was pushed ( abb190fd51cd2f9a9eef08c024e109f7f7e909fc ), which caused a buildbot failure, reverted ( 6227480d74da507cf8e1b4bcaffbdb9fb875b4b8 ), and then updated to fix buildbot failures (this patch).
Differential Revision: https://reviews.llvm.org/D40091
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@323788 91177308-0d34-0410-b5e6-96231b3b80d8
-amdgpu-waitcnt-forcezero={1|0} Force all waitcnt instrs to be emitted as s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
-amdgpu-waitcnt-forceexp=<n> Force emit a s_waitcnt expcnt(0) before the first <n> instrs
-amdgpu-waitcnt-forcelgkm=<n> Force emit a s_waitcnt lgkmcnt(0) before the first <n> instrs
-amdgpu-waitcnt-forcevm=<n> Force emit a s_waitcnt vmcnt(0) before the first <n> instrs
Differential Revision: https://reviews.llvm.org/D40091
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320084 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
The pass that inserts s_waitcnt instructions where needed propagated
info used to track dependencies for each block by iterating over the
predecessor blocks. The iteration was terminated when a predecessor
that had not yet been processed was encountered. Any info in blocks
later in the list was therefore not processed, leading to the
possiblility of a required s_waitcnt not being inserted.
The fix is simply to change the "break" to "continue" for the
relevant loops, so that all visited blocks are processed. This
is likely what was intended when the code was written.
There is no test case provided for this fix because:
1) the only example that reproduces this is large and resistant to
being reduced
2) the change is trivial
Subscribers: arsenm, kzhuravl, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye
Differential Revision: https://reviews.llvm.org/D40544
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@319651 91177308-0d34-0410-b5e6-96231b3b80d8
This is mostly moving VMEM clause breaking into
the hazard recognizer. Also move another hazard
currently handled in the waitcnt pass.
Also stops breaking clauses unless xnack is enabled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318557 91177308-0d34-0410-b5e6-96231b3b80d8
There are 2 more places doing this, but I'm not sure
what they are doing and don't make any sense to me
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308770 91177308-0d34-0410-b5e6-96231b3b80d8
- new waitcnt pass remains off by default; -enable-si-insert-waitcnts=1 to enable it
- fix handling of PERMUTE ops
- fix insertion of waitcnt instrs at function begin/end ( port of analogous code that was added to old waitcnt pass )
- add new test
Differential Revision: https://reviews.llvm.org/D33114
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304311 91177308-0d34-0410-b5e6-96231b3b80d8
1. RegisterClass::getSize() is split into two functions:
- TargetRegisterInfo::getRegSizeInBits(const TargetRegisterClass &RC) const;
- TargetRegisterInfo::getSpillSize(const TargetRegisterClass &RC) const;
2. RegisterClass::getAlignment() is replaced by:
- TargetRegisterInfo::getSpillAlignment(const TargetRegisterClass &RC) const;
This will allow making those values depend on subtarget features in the
future.
Differential Revision: https://reviews.llvm.org/D31783
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301221 91177308-0d34-0410-b5e6-96231b3b80d8
