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[AMDGPU][Attributor] Rework calculation of waves per eu
1 parent 34fd831 commit 0b40b9b

31 files changed

+281
-267
lines changed

llvm/lib/Target/AMDGPU/AMDGPUAttributor.cpp

Lines changed: 74 additions & 51 deletions
Original file line numberDiff line numberDiff line change
@@ -1109,74 +1109,38 @@ struct AAAMDWavesPerEU : public AAAMDSizeRangeAttribute {
11091109
Function *F = getAssociatedFunction();
11101110
auto &InfoCache = static_cast<AMDGPUInformationCache &>(A.getInfoCache());
11111111

1112-
auto TakeRange = [&](std::pair<unsigned, unsigned> R) {
1113-
auto [Min, Max] = R;
1114-
ConstantRange Range(APInt(32, Min), APInt(32, Max + 1));
1115-
IntegerRangeState RangeState(Range);
1116-
clampStateAndIndicateChange(this->getState(), RangeState);
1117-
indicateOptimisticFixpoint();
1118-
};
1119-
1120-
std::pair<unsigned, unsigned> MaxWavesPerEURange{
1121-
1U, InfoCache.getMaxWavesPerEU(*F)};
1122-
11231112
// If the attribute exists, we will honor it if it is not the default.
11241113
if (auto Attr = InfoCache.getWavesPerEUAttr(*F)) {
1114+
std::pair<unsigned, unsigned> MaxWavesPerEURange{
1115+
1U, InfoCache.getMaxWavesPerEU(*F)};
11251116
if (*Attr != MaxWavesPerEURange) {
1126-
TakeRange(*Attr);
1117+
auto [Min, Max] = *Attr;
1118+
ConstantRange Range(APInt(32, Min), APInt(32, Max + 1));
1119+
IntegerRangeState RangeState(Range);
1120+
clampStateAndIndicateChange(this->getState(), RangeState);
1121+
indicateOptimisticFixpoint();
11271122
return;
11281123
}
11291124
}
11301125

1131-
// Unlike AAAMDFlatWorkGroupSize, it's getting trickier here. Since the
1132-
// calculation of waves per EU involves flat work group size, we can't
1133-
// simply use an assumed flat work group size as a start point, because the
1134-
// update of flat work group size is in an inverse direction of waves per
1135-
// EU. However, we can still do something if it is an entry function. Since
1136-
// an entry function is a terminal node, and flat work group size either
1137-
// from attribute or default will be used anyway, we can take that value and
1138-
// calculate the waves per EU based on it. This result can't be updated by
1139-
// no means, but that could still allow us to propagate it.
1140-
if (AMDGPU::isEntryFunctionCC(F->getCallingConv())) {
1141-
std::pair<unsigned, unsigned> FlatWorkGroupSize;
1142-
if (auto Attr = InfoCache.getFlatWorkGroupSizeAttr(*F))
1143-
FlatWorkGroupSize = *Attr;
1144-
else
1145-
FlatWorkGroupSize = InfoCache.getDefaultFlatWorkGroupSize(*F);
1146-
TakeRange(InfoCache.getEffectiveWavesPerEU(*F, MaxWavesPerEURange,
1147-
FlatWorkGroupSize));
1148-
}
1126+
if (AMDGPU::isEntryFunctionCC(F->getCallingConv()))
1127+
indicatePessimisticFixpoint();
11491128
}
11501129

11511130
ChangeStatus updateImpl(Attributor &A) override {
1152-
auto &InfoCache = static_cast<AMDGPUInformationCache &>(A.getInfoCache());
11531131
ChangeStatus Change = ChangeStatus::UNCHANGED;
11541132

11551133
auto CheckCallSite = [&](AbstractCallSite CS) {
11561134
Function *Caller = CS.getInstruction()->getFunction();
1157-
Function *Func = getAssociatedFunction();
1158-
LLVM_DEBUG(dbgs() << '[' << getName() << "] Call " << Caller->getName()
1159-
<< "->" << Func->getName() << '\n');
1160-
11611135
const auto *CallerInfo = A.getAAFor<AAAMDWavesPerEU>(
11621136
*this, IRPosition::function(*Caller), DepClassTy::REQUIRED);
1163-
const auto *AssumedGroupSize = A.getAAFor<AAAMDFlatWorkGroupSize>(
1164-
*this, IRPosition::function(*Func), DepClassTy::REQUIRED);
1165-
if (!CallerInfo || !AssumedGroupSize || !CallerInfo->isValidState() ||
1166-
!AssumedGroupSize->isValidState())
1137+
if (!CallerInfo || !CallerInfo->isValidState())
11671138
return false;
1168-
1169-
unsigned Min, Max;
1170-
std::tie(Min, Max) = InfoCache.getEffectiveWavesPerEU(
1171-
*Caller,
1172-
{CallerInfo->getAssumed().getLower().getZExtValue(),
1173-
CallerInfo->getAssumed().getUpper().getZExtValue() - 1},
1174-
{AssumedGroupSize->getAssumed().getLower().getZExtValue(),
1175-
AssumedGroupSize->getAssumed().getUpper().getZExtValue() - 1});
1176-
ConstantRange CallerRange(APInt(32, Min), APInt(32, Max + 1));
1139+
unsigned Min = CallerInfo->getAssumed().getLower().getZExtValue();
1140+
unsigned Max = CallerInfo->getAssumed().getUpper().getZExtValue();
1141+
ConstantRange CallerRange(APInt(32, Min), APInt(32, Max));
11771142
IntegerRangeState CallerRangeState(CallerRange);
11781143
Change |= clampStateAndIndicateChange(this->getState(), CallerRangeState);
1179-
11801144
return true;
11811145
};
11821146

@@ -1329,6 +1293,59 @@ static void addPreloadKernArgHint(Function &F, TargetMachine &TM) {
13291293
}
13301294
}
13311295

1296+
static void checkWavesPerEU(Module &M, TargetMachine &TM) {
1297+
for (Function &F : M) {
1298+
const GCNSubtarget &ST = TM.getSubtarget<GCNSubtarget>(F);
1299+
1300+
auto FlatWgrpSizeAttr =
1301+
AMDGPU::getIntegerPairAttribute(F, "amdgpu-flat-work-group-size");
1302+
auto WavesPerEUAttr = AMDGPU::getIntegerPairAttribute(
1303+
F, "amdgpu-waves-per-eu", /*OnlyFirstRequired=*/true);
1304+
1305+
unsigned MinWavesPerEU = ST.getMinWavesPerEU();
1306+
unsigned MaxWavesPerEU = ST.getMaxWavesPerEU();
1307+
1308+
unsigned MinFlatWgrpSize = 1U;
1309+
unsigned MaxFlatWgrpSize = 1024U;
1310+
if (FlatWgrpSizeAttr.has_value()) {
1311+
MinFlatWgrpSize = FlatWgrpSizeAttr->first;
1312+
MaxFlatWgrpSize = *(FlatWgrpSizeAttr->second);
1313+
}
1314+
1315+
// Start with the max range.
1316+
unsigned Min = MinWavesPerEU;
1317+
unsigned Max = MaxWavesPerEU;
1318+
1319+
// If the attribute exists, set them to the value from the attribute.
1320+
if (WavesPerEUAttr.has_value()) {
1321+
Min = WavesPerEUAttr->first;
1322+
if (WavesPerEUAttr->second.has_value())
1323+
Max = *(WavesPerEUAttr->second);
1324+
}
1325+
1326+
// Compute the range from flat workgroup size.
1327+
auto [MinFromFlatWgrpSize, MaxFromFlatWgrpSize] =
1328+
ST.getWavesPerEU(F, std::make_pair(MinFlatWgrpSize, MaxFlatWgrpSize));
1329+
1330+
// For the lower bound, we have to "tighten" it.
1331+
Min = std::max(Min, MinFromFlatWgrpSize);
1332+
// For the upper bound, we have to "extend" it.
1333+
Max = std::max(Max, MaxFromFlatWgrpSize);
1334+
1335+
// Clamp the range to the max range.
1336+
Min = std::max(Min, MinWavesPerEU);
1337+
Max = std::min(Max, MaxWavesPerEU);
1338+
1339+
// Update the attribute if it is not the max.
1340+
if (Min != MinWavesPerEU || Max != MaxWavesPerEU) {
1341+
SmallString<10> Buffer;
1342+
raw_svector_ostream OS(Buffer);
1343+
OS << Min << ',' << Max;
1344+
F.addFnAttr("amdgpu-waves-per-eu", OS.str());
1345+
}
1346+
}
1347+
}
1348+
13321349
static bool runImpl(Module &M, AnalysisGetter &AG, TargetMachine &TM,
13331350
AMDGPUAttributorOptions Options,
13341351
ThinOrFullLTOPhase LTOPhase) {
@@ -1421,8 +1438,14 @@ static bool runImpl(Module &M, AnalysisGetter &AG, TargetMachine &TM,
14211438
}
14221439
}
14231440

1424-
ChangeStatus Change = A.run();
1425-
return Change == ChangeStatus::CHANGED;
1441+
bool Changed = A.run() == ChangeStatus::CHANGED;
1442+
1443+
if (Changed && (LTOPhase == ThinOrFullLTOPhase::None ||
1444+
LTOPhase == ThinOrFullLTOPhase::FullLTOPostLink ||
1445+
LTOPhase == ThinOrFullLTOPhase::ThinLTOPostLink))
1446+
checkWavesPerEU(M, TM);
1447+
1448+
return Changed;
14261449
}
14271450

14281451
class AMDGPUAttributorLegacy : public ModulePass {

llvm/test/CodeGen/AMDGPU/addrspacecast-constantexpr.ll

Lines changed: 3 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -232,9 +232,9 @@ attributes #1 = { nounwind }
232232
; AKF_HSA: attributes #[[ATTR0:[0-9]+]] = { nocallback nofree nounwind willreturn memory(argmem: readwrite) }
233233
; AKF_HSA: attributes #[[ATTR1]] = { nounwind }
234234
;.
235-
; ATTRIBUTOR_HSA: attributes #[[ATTR0:[0-9]+]] = { nocallback nofree nounwind willreturn memory(argmem: readwrite) }
236-
; ATTRIBUTOR_HSA: attributes #[[ATTR1]] = { nounwind "amdgpu-no-agpr" "amdgpu-no-completion-action" "amdgpu-no-default-queue" "amdgpu-no-dispatch-id" "amdgpu-no-dispatch-ptr" "amdgpu-no-flat-scratch-init" "amdgpu-no-heap-ptr" "amdgpu-no-hostcall-ptr" "amdgpu-no-implicitarg-ptr" "amdgpu-no-lds-kernel-id" "amdgpu-no-multigrid-sync-arg" "amdgpu-no-queue-ptr" "amdgpu-no-workgroup-id-x" "amdgpu-no-workgroup-id-y" "amdgpu-no-workgroup-id-z" "amdgpu-no-workitem-id-x" "amdgpu-no-workitem-id-y" "amdgpu-no-workitem-id-z" "uniform-work-group-size"="false" }
237-
; ATTRIBUTOR_HSA: attributes #[[ATTR2]] = { nounwind "amdgpu-no-agpr" "amdgpu-no-completion-action" "amdgpu-no-default-queue" "amdgpu-no-dispatch-id" "amdgpu-no-dispatch-ptr" "amdgpu-no-flat-scratch-init" "amdgpu-no-heap-ptr" "amdgpu-no-hostcall-ptr" "amdgpu-no-lds-kernel-id" "amdgpu-no-multigrid-sync-arg" "amdgpu-no-queue-ptr" "amdgpu-no-workgroup-id-x" "amdgpu-no-workgroup-id-y" "amdgpu-no-workgroup-id-z" "amdgpu-no-workitem-id-x" "amdgpu-no-workitem-id-y" "amdgpu-no-workitem-id-z" "uniform-work-group-size"="false" }
235+
; ATTRIBUTOR_HSA: attributes #[[ATTR0:[0-9]+]] = { nocallback nofree nounwind willreturn memory(argmem: readwrite) "amdgpu-waves-per-eu"="4,10" }
236+
; ATTRIBUTOR_HSA: attributes #[[ATTR1]] = { nounwind "amdgpu-no-agpr" "amdgpu-no-completion-action" "amdgpu-no-default-queue" "amdgpu-no-dispatch-id" "amdgpu-no-dispatch-ptr" "amdgpu-no-flat-scratch-init" "amdgpu-no-heap-ptr" "amdgpu-no-hostcall-ptr" "amdgpu-no-implicitarg-ptr" "amdgpu-no-lds-kernel-id" "amdgpu-no-multigrid-sync-arg" "amdgpu-no-queue-ptr" "amdgpu-no-workgroup-id-x" "amdgpu-no-workgroup-id-y" "amdgpu-no-workgroup-id-z" "amdgpu-no-workitem-id-x" "amdgpu-no-workitem-id-y" "amdgpu-no-workitem-id-z" "amdgpu-waves-per-eu"="4,10" "uniform-work-group-size"="false" }
237+
; ATTRIBUTOR_HSA: attributes #[[ATTR2]] = { nounwind "amdgpu-no-agpr" "amdgpu-no-completion-action" "amdgpu-no-default-queue" "amdgpu-no-dispatch-id" "amdgpu-no-dispatch-ptr" "amdgpu-no-flat-scratch-init" "amdgpu-no-heap-ptr" "amdgpu-no-hostcall-ptr" "amdgpu-no-lds-kernel-id" "amdgpu-no-multigrid-sync-arg" "amdgpu-no-queue-ptr" "amdgpu-no-workgroup-id-x" "amdgpu-no-workgroup-id-y" "amdgpu-no-workgroup-id-z" "amdgpu-no-workitem-id-x" "amdgpu-no-workitem-id-y" "amdgpu-no-workitem-id-z" "amdgpu-waves-per-eu"="4,10" "uniform-work-group-size"="false" }
238238
;.
239239
; AKF_HSA: [[META0:![0-9]+]] = !{i32 1, !"amdhsa_code_object_version", i32 500}
240240
;.

llvm/test/CodeGen/AMDGPU/amdgpu-attributor-no-agpr.ll

Lines changed: 6 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -254,11 +254,11 @@ define amdgpu_kernel void @indirect_calls_none_agpr(i1 %cond) {
254254

255255
attributes #0 = { "amdgpu-no-agpr" }
256256
;.
257-
; CHECK: attributes #[[ATTR0]] = { "amdgpu-no-completion-action" "amdgpu-no-default-queue" "amdgpu-no-dispatch-id" "amdgpu-no-dispatch-ptr" "amdgpu-no-flat-scratch-init" "amdgpu-no-heap-ptr" "amdgpu-no-hostcall-ptr" "amdgpu-no-implicitarg-ptr" "amdgpu-no-lds-kernel-id" "amdgpu-no-multigrid-sync-arg" "amdgpu-no-queue-ptr" "amdgpu-no-workgroup-id-x" "amdgpu-no-workgroup-id-y" "amdgpu-no-workgroup-id-z" "amdgpu-no-workitem-id-x" "amdgpu-no-workitem-id-y" "amdgpu-no-workitem-id-z" "target-cpu"="gfx90a" "uniform-work-group-size"="false" }
258-
; CHECK: attributes #[[ATTR1]] = { "amdgpu-no-agpr" "amdgpu-no-completion-action" "amdgpu-no-default-queue" "amdgpu-no-dispatch-id" "amdgpu-no-dispatch-ptr" "amdgpu-no-flat-scratch-init" "amdgpu-no-heap-ptr" "amdgpu-no-hostcall-ptr" "amdgpu-no-implicitarg-ptr" "amdgpu-no-lds-kernel-id" "amdgpu-no-multigrid-sync-arg" "amdgpu-no-queue-ptr" "amdgpu-no-workgroup-id-x" "amdgpu-no-workgroup-id-y" "amdgpu-no-workgroup-id-z" "amdgpu-no-workitem-id-x" "amdgpu-no-workitem-id-y" "amdgpu-no-workitem-id-z" "target-cpu"="gfx90a" "uniform-work-group-size"="false" }
259-
; CHECK: attributes #[[ATTR2]] = { "target-cpu"="gfx90a" "uniform-work-group-size"="false" }
260-
; CHECK: attributes #[[ATTR3:[0-9]+]] = { convergent nocallback nofree nosync nounwind willreturn memory(none) "target-cpu"="gfx90a" }
261-
; CHECK: attributes #[[ATTR4:[0-9]+]] = { nocallback nofree nosync nounwind speculatable willreturn memory(none) "target-cpu"="gfx90a" }
262-
; CHECK: attributes #[[ATTR5:[0-9]+]] = { nocallback nofree nounwind willreturn memory(argmem: readwrite) "target-cpu"="gfx90a" }
257+
; CHECK: attributes #[[ATTR0]] = { "amdgpu-no-completion-action" "amdgpu-no-default-queue" "amdgpu-no-dispatch-id" "amdgpu-no-dispatch-ptr" "amdgpu-no-flat-scratch-init" "amdgpu-no-heap-ptr" "amdgpu-no-hostcall-ptr" "amdgpu-no-implicitarg-ptr" "amdgpu-no-lds-kernel-id" "amdgpu-no-multigrid-sync-arg" "amdgpu-no-queue-ptr" "amdgpu-no-workgroup-id-x" "amdgpu-no-workgroup-id-y" "amdgpu-no-workgroup-id-z" "amdgpu-no-workitem-id-x" "amdgpu-no-workitem-id-y" "amdgpu-no-workitem-id-z" "amdgpu-waves-per-eu"="4,8" "target-cpu"="gfx90a" "uniform-work-group-size"="false" }
258+
; CHECK: attributes #[[ATTR1]] = { "amdgpu-no-agpr" "amdgpu-no-completion-action" "amdgpu-no-default-queue" "amdgpu-no-dispatch-id" "amdgpu-no-dispatch-ptr" "amdgpu-no-flat-scratch-init" "amdgpu-no-heap-ptr" "amdgpu-no-hostcall-ptr" "amdgpu-no-implicitarg-ptr" "amdgpu-no-lds-kernel-id" "amdgpu-no-multigrid-sync-arg" "amdgpu-no-queue-ptr" "amdgpu-no-workgroup-id-x" "amdgpu-no-workgroup-id-y" "amdgpu-no-workgroup-id-z" "amdgpu-no-workitem-id-x" "amdgpu-no-workitem-id-y" "amdgpu-no-workitem-id-z" "amdgpu-waves-per-eu"="4,8" "target-cpu"="gfx90a" "uniform-work-group-size"="false" }
259+
; CHECK: attributes #[[ATTR2]] = { "amdgpu-waves-per-eu"="4,8" "target-cpu"="gfx90a" "uniform-work-group-size"="false" }
260+
; CHECK: attributes #[[ATTR3:[0-9]+]] = { convergent nocallback nofree nosync nounwind willreturn memory(none) "amdgpu-waves-per-eu"="4,8" "target-cpu"="gfx90a" }
261+
; CHECK: attributes #[[ATTR4:[0-9]+]] = { nocallback nofree nosync nounwind speculatable willreturn memory(none) "amdgpu-waves-per-eu"="4,8" "target-cpu"="gfx90a" }
262+
; CHECK: attributes #[[ATTR5:[0-9]+]] = { nocallback nofree nounwind willreturn memory(argmem: readwrite) "amdgpu-waves-per-eu"="4,8" "target-cpu"="gfx90a" }
263263
; CHECK: attributes #[[ATTR6]] = { "amdgpu-no-agpr" }
264264
;.

llvm/test/CodeGen/AMDGPU/annotate-existing-abi-attributes.ll

Lines changed: 10 additions & 10 deletions
Original file line numberDiff line numberDiff line change
@@ -117,14 +117,14 @@ define void @call_no_dispatch_id() {
117117
ret void
118118
}
119119
;.
120-
; CHECK: attributes #[[ATTR0]] = { "amdgpu-no-workitem-id-x" "uniform-work-group-size"="false" }
121-
; CHECK: attributes #[[ATTR1]] = { "amdgpu-no-workitem-id-y" "uniform-work-group-size"="false" }
122-
; CHECK: attributes #[[ATTR2]] = { "amdgpu-no-workitem-id-z" "uniform-work-group-size"="false" }
123-
; CHECK: attributes #[[ATTR3]] = { "amdgpu-no-workgroup-id-x" "uniform-work-group-size"="false" }
124-
; CHECK: attributes #[[ATTR4]] = { "amdgpu-no-workgroup-id-y" "uniform-work-group-size"="false" }
125-
; CHECK: attributes #[[ATTR5]] = { "amdgpu-no-workgroup-id-z" "uniform-work-group-size"="false" }
126-
; CHECK: attributes #[[ATTR6]] = { "amdgpu-no-dispatch-ptr" "uniform-work-group-size"="false" }
127-
; CHECK: attributes #[[ATTR7]] = { "amdgpu-no-queue-ptr" "uniform-work-group-size"="false" }
128-
; CHECK: attributes #[[ATTR8]] = { "amdgpu-no-implicitarg-ptr" "uniform-work-group-size"="false" }
129-
; CHECK: attributes #[[ATTR9]] = { "amdgpu-no-dispatch-id" "uniform-work-group-size"="false" }
120+
; CHECK: attributes #[[ATTR0]] = { "amdgpu-no-workitem-id-x" "amdgpu-waves-per-eu"="4,10" "uniform-work-group-size"="false" }
121+
; CHECK: attributes #[[ATTR1]] = { "amdgpu-no-workitem-id-y" "amdgpu-waves-per-eu"="4,10" "uniform-work-group-size"="false" }
122+
; CHECK: attributes #[[ATTR2]] = { "amdgpu-no-workitem-id-z" "amdgpu-waves-per-eu"="4,10" "uniform-work-group-size"="false" }
123+
; CHECK: attributes #[[ATTR3]] = { "amdgpu-no-workgroup-id-x" "amdgpu-waves-per-eu"="4,10" "uniform-work-group-size"="false" }
124+
; CHECK: attributes #[[ATTR4]] = { "amdgpu-no-workgroup-id-y" "amdgpu-waves-per-eu"="4,10" "uniform-work-group-size"="false" }
125+
; CHECK: attributes #[[ATTR5]] = { "amdgpu-no-workgroup-id-z" "amdgpu-waves-per-eu"="4,10" "uniform-work-group-size"="false" }
126+
; CHECK: attributes #[[ATTR6]] = { "amdgpu-no-dispatch-ptr" "amdgpu-waves-per-eu"="4,10" "uniform-work-group-size"="false" }
127+
; CHECK: attributes #[[ATTR7]] = { "amdgpu-no-queue-ptr" "amdgpu-waves-per-eu"="4,10" "uniform-work-group-size"="false" }
128+
; CHECK: attributes #[[ATTR8]] = { "amdgpu-no-implicitarg-ptr" "amdgpu-waves-per-eu"="4,10" "uniform-work-group-size"="false" }
129+
; CHECK: attributes #[[ATTR9]] = { "amdgpu-no-dispatch-id" "amdgpu-waves-per-eu"="4,10" "uniform-work-group-size"="false" }
130130
;.

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