STATISTIC(NumTailCalls, "Number of tail calls");
+static cl::opt<unsigned> ExtensionMaxWebSize(
+ DEBUG_TYPE "-ext-max-web-size", cl::Hidden,
+ cl::desc("Give the maximum size (in number of nodes) of the web of "
+ "instructions that we will consider for VW expansion"),
+ cl::init(18));
+
static cl::opt<bool>
AllowSplatInVW_W(DEBUG_TYPE "-form-vw-w-with-splat", cl::Hidden,
cl::desc("Allow the formation of VW_W operations (e.g., "
/// Root of the combine.
SDNode *Root;
/// LHS of the TargetOpcode.
- const NodeExtensionHelper &LHS;
+ NodeExtensionHelper LHS;
/// RHS of the TargetOpcode.
- const NodeExtensionHelper &RHS;
+ NodeExtensionHelper RHS;
CombineResult(unsigned TargetOpcode, SDNode *Root,
const NodeExtensionHelper &LHS, Optional<bool> SExtLHS,
assert(NodeExtensionHelper::isSupportedRoot(N) &&
"Shouldn't have called this method");
+ SmallVector<SDNode *> Worklist;
+ SmallSet<SDNode *, 8> Inserted;
+ Worklist.push_back(N);
+ Inserted.insert(N);
+ SmallVector<CombineResult> CombinesToApply;
+
+ while (!Worklist.empty()) {
+ SDNode *Root = Worklist.pop_back_val();
+ if (!NodeExtensionHelper::isSupportedRoot(Root))
+ return SDValue();
- NodeExtensionHelper LHS(N, 0, DAG);
- NodeExtensionHelper RHS(N, 1, DAG);
-
- if (LHS.needToPromoteOtherUsers() && !LHS.OrigOperand.hasOneUse())
- return SDValue();
-
- if (RHS.needToPromoteOtherUsers() && !RHS.OrigOperand.hasOneUse())
- return SDValue();
+ NodeExtensionHelper LHS(N, 0, DAG);
+ NodeExtensionHelper RHS(N, 1, DAG);
+ auto AppendUsersIfNeeded = [&Worklist,
+ &Inserted](const NodeExtensionHelper &Op) {
+ if (Op.needToPromoteOtherUsers()) {
+ for (SDNode *TheUse : Op.OrigOperand->uses()) {
+ if (Inserted.insert(TheUse).second)
+ Worklist.push_back(TheUse);
+ }
+ }
+ };
+ AppendUsersIfNeeded(LHS);
+ AppendUsersIfNeeded(RHS);
- SmallVector<NodeExtensionHelper::CombineToTry> FoldingStrategies =
- NodeExtensionHelper::getSupportedFoldings(N);
+ // Control the compile time by limiting the number of node we look at in
+ // total.
+ if (Inserted.size() > ExtensionMaxWebSize)
+ return SDValue();
- assert(!FoldingStrategies.empty() && "Nothing to be folded");
- for (int Attempt = 0; Attempt != 1 + NodeExtensionHelper::isCommutative(N);
- ++Attempt) {
- for (NodeExtensionHelper::CombineToTry FoldingStrategy :
- FoldingStrategies) {
- Optional<CombineResult> Res = FoldingStrategy(N, LHS, RHS);
- if (Res)
- return Res->materialize(DAG);
+ SmallVector<NodeExtensionHelper::CombineToTry> FoldingStrategies =
+ NodeExtensionHelper::getSupportedFoldings(N);
+
+ assert(!FoldingStrategies.empty() && "Nothing to be folded");
+ bool Matched = false;
+ for (int Attempt = 0;
+ (Attempt != 1 + NodeExtensionHelper::isCommutative(N)) && !Matched;
+ ++Attempt) {
+
+ for (NodeExtensionHelper::CombineToTry FoldingStrategy :
+ FoldingStrategies) {
+ Optional<CombineResult> Res = FoldingStrategy(N, LHS, RHS);
+ if (Res) {
+ Matched = true;
+ CombinesToApply.push_back(*Res);
+ break;
+ }
+ }
+ std::swap(LHS, RHS);
}
- std::swap(LHS, RHS);
+ // Right now we do an all or nothing approach.
+ if (!Matched)
+ return SDValue();
}
- return SDValue();
+ // Store the value for the replacement of the input node separately.
+ SDValue InputRootReplacement;
+ // We do the RAUW after we materialize all the combines, because some replaced
+ // nodes may be feeding some of the yet-to-be-replaced nodes. Put differently,
+ // some of these nodes may appear in the NodeExtensionHelpers of some of the
+ // yet-to-be-visited CombinesToApply roots.
+ SmallVector<std::pair<SDValue, SDValue>> ValuesToReplace;
+ ValuesToReplace.reserve(CombinesToApply.size());
+ for (CombineResult Res : CombinesToApply) {
+ SDValue NewValue = Res.materialize(DAG);
+ if (!InputRootReplacement) {
+ assert(Res.Root == N &&
+ "First element is expected to be the current node");
+ InputRootReplacement = NewValue;
+ } else {
+ ValuesToReplace.emplace_back(SDValue(Res.Root, 0), NewValue);
+ }
+ }
+ for (std::pair<SDValue, SDValue> OldNewValues : ValuesToReplace) {
+ DAG.ReplaceAllUsesOfValueWith(OldNewValues.first, OldNewValues.second);
+ DCI.AddToWorklist(OldNewValues.second.getNode());
+ }
+ return InputRootReplacement;
}
// Fold
--- /dev/null
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=riscv32 -mattr=+v -riscv-v-vector-bits-min=128 -verify-machineinstrs %s -o - --riscv-lower-ext-max-web-size=1 | FileCheck %s --check-prefixes=NO_FOLDING
+; RUN: llc -mtriple=riscv64 -mattr=+v -riscv-v-vector-bits-min=128 -verify-machineinstrs %s -o - --riscv-lower-ext-max-web-size=1 | FileCheck %s --check-prefixes=NO_FOLDING
+; RUN: llc -mtriple=riscv32 -mattr=+v -riscv-v-vector-bits-min=128 -verify-machineinstrs %s -o - --riscv-lower-ext-max-web-size=2 | FileCheck %s --check-prefixes=NO_FOLDING
+; RUN: llc -mtriple=riscv64 -mattr=+v -riscv-v-vector-bits-min=128 -verify-machineinstrs %s -o - --riscv-lower-ext-max-web-size=2 | FileCheck %s --check-prefixes=NO_FOLDING
+; RUN: llc -mtriple=riscv32 -mattr=+v -riscv-v-vector-bits-min=128 -verify-machineinstrs %s -o - --riscv-lower-ext-max-web-size=3 | FileCheck %s --check-prefixes=FOLDING
+; RUN: llc -mtriple=riscv64 -mattr=+v -riscv-v-vector-bits-min=128 -verify-machineinstrs %s -o - --riscv-lower-ext-max-web-size=3 | FileCheck %s --check-prefixes=FOLDING
+; Check that the default value enables the web folding and
+; that it is bigger than 3.
+; RUN: llc -mtriple=riscv32 -mattr=+v -riscv-v-vector-bits-min=128 -verify-machineinstrs %s -o - | FileCheck %s --check-prefixes=FOLDING
+; RUN: llc -mtriple=riscv64 -mattr=+v -riscv-v-vector-bits-min=128 -verify-machineinstrs %s -o - | FileCheck %s --check-prefixes=FOLDING
+
+
+; Check that the add/sub/mul operations are all promoted into their
+; vw counterpart when the folding of the web size is increased to 3.
+; We need the web size to be at least 3 for the folding to happen, because
+; %c has 3 uses.
+define <2 x i16> @vwmul_v2i16_multiple_users(<2 x i8>* %x, <2 x i8>* %y, <2 x i8> *%z) {
+; NO_FOLDING-LABEL: vwmul_v2i16_multiple_users:
+; NO_FOLDING: # %bb.0:
+; NO_FOLDING-NEXT: vsetivli zero, 2, e16, mf4, ta, mu
+; NO_FOLDING-NEXT: vle8.v v8, (a0)
+; NO_FOLDING-NEXT: vle8.v v9, (a1)
+; NO_FOLDING-NEXT: vle8.v v10, (a2)
+; NO_FOLDING-NEXT: vsext.vf2 v11, v8
+; NO_FOLDING-NEXT: vsext.vf2 v8, v9
+; NO_FOLDING-NEXT: vsext.vf2 v9, v10
+; NO_FOLDING-NEXT: vmul.vv v8, v11, v8
+; NO_FOLDING-NEXT: vadd.vv v10, v11, v9
+; NO_FOLDING-NEXT: vsub.vv v9, v11, v9
+; NO_FOLDING-NEXT: vor.vv v8, v8, v10
+; NO_FOLDING-NEXT: vor.vv v8, v8, v9
+; NO_FOLDING-NEXT: ret
+;
+; FOLDING-LABEL: vwmul_v2i16_multiple_users:
+; FOLDING: # %bb.0:
+; FOLDING-NEXT: vsetivli zero, 2, e8, mf8, ta, mu
+; FOLDING-NEXT: vle8.v v8, (a0)
+; FOLDING-NEXT: vle8.v v9, (a1)
+; FOLDING-NEXT: vle8.v v10, (a2)
+; FOLDING-NEXT: vwmul.vv v11, v8, v9
+; FOLDING-NEXT: vwadd.vv v9, v8, v10
+; FOLDING-NEXT: vwsub.vv v12, v8, v10
+; FOLDING-NEXT: vsetvli zero, zero, e16, mf4, ta, mu
+; FOLDING-NEXT: vor.vv v8, v11, v9
+; FOLDING-NEXT: vor.vv v8, v8, v12
+; FOLDING-NEXT: ret
+ %a = load <2 x i8>, <2 x i8>* %x
+ %b = load <2 x i8>, <2 x i8>* %y
+ %b2 = load <2 x i8>, <2 x i8>* %z
+ %c = sext <2 x i8> %a to <2 x i16>
+ %d = sext <2 x i8> %b to <2 x i16>
+ %d2 = sext <2 x i8> %b2 to <2 x i16>
+ %e = mul <2 x i16> %c, %d
+ %f = add <2 x i16> %c, %d2
+ %g = sub <2 x i16> %c, %d2
+ %h = or <2 x i16> %e, %f
+ %i = or <2 x i16> %h, %g
+ ret <2 x i16> %i
+}
define <2 x i16> @vwmul_v2i16_multiple_users(<2 x i8>* %x, <2 x i8>* %y, <2 x i8> *%z) {
; CHECK-LABEL: vwmul_v2i16_multiple_users:
; CHECK: # %bb.0:
-; CHECK-NEXT: vsetivli zero, 2, e16, mf4, ta, mu
+; CHECK-NEXT: vsetivli zero, 2, e8, mf8, ta, mu
; CHECK-NEXT: vle8.v v8, (a0)
; CHECK-NEXT: vle8.v v9, (a1)
; CHECK-NEXT: vle8.v v10, (a2)
-; CHECK-NEXT: vsext.vf2 v11, v8
-; CHECK-NEXT: vsext.vf2 v8, v9
-; CHECK-NEXT: vsext.vf2 v9, v10
-; CHECK-NEXT: vmul.vv v8, v11, v8
-; CHECK-NEXT: vmul.vv v9, v11, v9
-; CHECK-NEXT: vor.vv v8, v8, v9
+; CHECK-NEXT: vwmul.vv v11, v8, v9
+; CHECK-NEXT: vwmul.vv v9, v8, v10
+; CHECK-NEXT: vsetvli zero, zero, e16, mf4, ta, mu
+; CHECK-NEXT: vor.vv v8, v11, v9
; CHECK-NEXT: ret
%a = load <2 x i8>, <2 x i8>* %x
%b = load <2 x i8>, <2 x i8>* %y