Summary:
Fix an issue where VGPR/SGPR bounds are not properly extended when brackets are merged.
This manifests as missing waitcnt insertions when multiple brackets are forwarded to a successor block and the first forward has lower VGPR/SGPR bounds.
Irreducible loop test has been extended based on a CTS failure detected for GFX9.
Reviewers: nhaehnle
Reviewed By: nhaehnle
Subscribers: arsenm, kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D55602
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349611 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
MachineLoopInfo cannot be relied on for correctness, because it cannot
properly recognize loops in irreducible control flow which can be
introduced by late machine basic block optimization passes. See the new
test case for the reduced form of an example that occurred in practice.
Use a simple fixpoint iteration instead.
In order to facilitate this change, refactor WaitcntBrackets so that it
only tracks pending events and registers, rather than also maintaining
state that is relevant for the high-level algorithm. Various accessor
methods can be removed or made private as a consequence.
Affects (in radv):
- dEQP-VK.glsl.loops.special.{for,while}_uniform_iterations.select_iteration_count_{fragment,vertex}
Fixes: r345719 ("AMDGPU: Rewrite SILowerI1Copies to always stay on SALU")
Reviewers: msearles, rampitec, scott.linder, kanarayan
Subscribers: arsenm, kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits, hakzsam
Differential Revision: https://reviews.llvm.org/D54231
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@347853 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
There is one obsolete reference to using -1 as an indication of "unknown",
but this isn't actually used anywhere.
Using unsigned makes robust wrapping checks easier.
Reviewers: msearles, rampitec, scott.linder, kanarayan
Subscribers: arsenm, kzhuravl, jvesely, wdng, yaxunl, dstuttard, llvm-commits, tpr, t-tye, hakzsam
Differential Revision: https://reviews.llvm.org/D54230
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@347852 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Instead of storing the "score" (last time point) of the various relevant
events, only store whether an event is pending or not.
This is sufficient, because whenever only one event of a count type is
pending, its last time point is naturally the upper bound of all time
points of this count type, and when multiple event types are pending,
the count type has gone out of order and an s_waitcnt to 0 is required
to clear any pending event type (and will then clear all pending event
types for that count type).
This also removes the special handling of GDS_GPR_LOCK and EXP_GPR_LOCK.
I do not understand what this special handling ever attempted to achieve.
It has existed ever since the original port from an internal code base,
so my best guess is that it solved a problem related to EXEC handling in
that internal code base.
Reviewers: msearles, rampitec, scott.linder, kanarayan
Subscribers: arsenm, kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits, hakzsam
Differential Revision: https://reviews.llvm.org/D54228
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@347850 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
It hides the type casting ugliness, and I happened to have to add a new
such loop (in a later patch).
Reviewers: msearles, rampitec, scott.linder, kanarayan
Subscribers: arsenm, kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits, hakzsam
Differential Revision: https://reviews.llvm.org/D54227
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@347849 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Reduce the statefulness of the algorithm in two ways:
1. More clearly split generateWaitcntInstBefore into two phases: the
first one which determines the required wait, if any, without changing
the ScoreBrackets, and the second one which actually inserts the wait
and updates the brackets.
2. Communicate pre-existing s_waitcnt instructions using an argument to
generateWaitcntInstBefore instead of through the ScoreBrackets.
To simplify these changes, a Waitcnt structure is introduced which carries
the counts of an s_waitcnt instruction in decoded form.
There are some functional changes:
1. The FIXME for the VCCZ bug workaround was implemented: we only wait for
SMEM instructions as required instead of waiting on all counters.
2. We now properly track pre-existing waitcnt's in all cases, which leads
to less conservative waitcnts being emitted in some cases.
s_load_dword ...
s_waitcnt lgkmcnt(0) <-- pre-existing wait count
ds_read_b32 v0, ...
ds_read_b32 v1, ...
s_waitcnt lgkmcnt(0) <-- this is too conservative
use(v0)
more code
use(v1)
This increases code size a bit, but the reduced latency should still be a
win in basically all cases. The worst code size regressions in my shader-db
are:
WORST REGRESSIONS - Code Size
Before After Delta Percentage
1724 1736 12 0.70 % shaders/private/f1-2015/1334.shader_test [0]
2276 2284 8 0.35 % shaders/private/f1-2015/1306.shader_test [0]
4632 4640 8 0.17 % shaders/private/ue4_elemental/62.shader_test [0]
2376 2384 8 0.34 % shaders/private/f1-2015/1308.shader_test [0]
3284 3292 8 0.24 % shaders/private/talos_principle/1955.shader_test [0]
Reviewers: msearles, rampitec, scott.linder, kanarayan
Subscribers: arsenm, kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits, hakzsam
Differential Revision: https://reviews.llvm.org/D54226
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@347848 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This is not needed, because we don't actually insert relevant branches
for KILLs that late in the compilation flow.
Besides, this was always checking for the wrong kill opcode anyway...
Reviewers: msearles, rampitec, scott.linder, kanarayan
Subscribers: arsenm, kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits
Differential Revision: https://reviews.llvm.org/D54085
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346362 91177308-0d34-0410-b5e6-96231b3b80d8
Move isa version determination into TargetParser.
Also switch away from target features to CPU string when
determining isa version. This fixes an issue when we
output wrong isa version in the object code when features
of a particular CPU are altered (i.e. gfx902 w/o xnack
used to result in gfx900).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@342069 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r341982.
The change introduced a layering violation. Reverting to unbreak
our integrate.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@342023 91177308-0d34-0410-b5e6-96231b3b80d8
into TargetParser.
Also switch away from target features to CPU string when
determining isa version. This fixes an issue when we
output wrong isa version in the object code when features
of a particular CPU are altered (i.e. gfx902 w/o xnack
used to result in gfx900).
Differential Revision: https://reviews.llvm.org/D51890
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@341982 91177308-0d34-0410-b5e6-96231b3b80d8
Re-apply "[AMDGPU][Waitcnt] fix "comparison of integers of different signs" build error""
( fe0a456510131f268e388c4a18a92f575c0db183 ), which was inadvertantly reverted via
2b2ee080f0164485562593b1b87291a48cea4a9a .
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@337156 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This is a follow-up to r335942.
- Merge SISubtarget into AMDGPUSubtarget and rename to GCNSubtarget
- Rename AMDGPUCommonSubtarget to AMDGPUSubtarget
- Merge R600Subtarget::Generation and GCNSubtarget::Generation into
AMDGPUSubtarget::Generation.
Reviewers: arsenm, jvesely
Subscribers: kzhuravl, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D49037
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@336851 91177308-0d34-0410-b5e6-96231b3b80d8
Build error on Android; reported by and fix provided by (thanks) by Mauro Rossi <issor.oruam@gmail.com>
Fixes the following building error:
external/llvm/lib/Target/AMDGPU/SIInsertWaitcnts.cpp:1903:61:
error: comparison of integers of different signs:
'typename iterator_traits<__wrap_iter<MachineBasicBlock **> >::difference_type'
(aka 'int') and 'unsigned int' [-Werror,-Wsign-compare]
BlockWaitcntProcessedSet.end(), &MBB) < Count)) {
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^ ~~~~~
1 error generated.
Differential Revision: https://reviews.llvm.org/D49089
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@336588 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
We now have two sets of generated TableGen files, one for R600 and one
for GCN, so each sub-target now has its own tables of instructions,
registers, ISel patterns, etc. This should help reduce compile time
since each sub-target now only has to consider information that
is specific to itself. This will also help prevent the R600
sub-target from slowing down new features for GCN, like disassembler
support, GlobalISel, etc.
Reviewers: arsenm, nhaehnle, jvesely
Reviewed By: arsenm
Subscribers: MatzeB, kzhuravl, wdng, mgorny, yaxunl, dstuttard, tpr, t-tye, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D46365
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@335942 91177308-0d34-0410-b5e6-96231b3b80d8
In terms of waitcnt insertion/if necessary, the waitcnt pass forces convergence
for a loop. Previously, that kicked if greater than 2 passes over a loop, which
doesn't account for loop with many bottom blocks. So, increase the threshold to
(n+1), where n is the number of bottom blocks. This gives the pass an
opportunity to consider the contribution of each bottom block, to the overall
loop, before the forced convergence potentially kicks in.
Differential Revision: https://reviews.llvm.org/D47488
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@333556 91177308-0d34-0410-b5e6-96231b3b80d8
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.
In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.
Differential Revision: https://reviews.llvm.org/D43624
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@332240 91177308-0d34-0410-b5e6-96231b3b80d8
Because we create a new kind of debug instruction, DBG_LABEL, we need to
check all passes which use isDebugValue() to check MachineInstr is debug
instruction or not. When expelling debug instructions, we should expel
both DBG_VALUE and DBG_LABEL. So, I create a new function,
isDebugInstr(), in MachineInstr to check whether the MachineInstr is
debug instruction or not.
This patch has no new test case. I have run regression test and there is
no difference in regression test.
Differential Revision: https://reviews.llvm.org/D45342
Patch by Hsiangkai Wang.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331844 91177308-0d34-0410-b5e6-96231b3b80d8
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done
Differential Revision: https://reviews.llvm.org/D46290
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331272 91177308-0d34-0410-b5e6-96231b3b80d8
- Add "amdgpu-waitcnt-forcezero" to force all waitcnt instrs to be emitted as s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
- Add debug counters to control force emit of s_waitcnt instrs; debug counters:
si-insert-waitcnts-forceexp: force emit s_waitcnt expcnt(0) instrs
si-insert-waitcnts-forcevm: force emit s_waitcnt lgkmcnt(0) instrs
si-insert-waitcnts-forcelgkm: force emit s_waitcnt vmcnt(0) instrs
- Add some debug statements
Note that a variant of this patch was previously committed/reverted.
Differential Revision: https://reviews.llvm.org/D45888
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@330862 91177308-0d34-0410-b5e6-96231b3b80d8
We should also check that the "bottom" basic block of a loopis a successor of the "header" basic block, otherwise we don't propagate the information correctly when the CFG is complex. This fixes an important rendering problem with Wolfsentein 2, because of one vector-memory wait was missing.
Differential Revision: https://reviews.llvm.org/D43831
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@330337 91177308-0d34-0410-b5e6-96231b3b80d8
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
