[NFC][Clang][RISCV] Reduce boilerplate when determining prototype for segment loads

No functionality change of the RVV builtin and compiler intrinsics is intended
in this patch.

This patch gathers scattered comments for the segment load builtin/intrinsics
and its variants (e.g. segment unit-stride load, segment strided load) into a
single paragraph under riscv_vector.td.

This patch also tries to reduce one level of the if-statements as the push_back
are essentially the same actions but differs in index based on the the value
of the policy attributes and whether the intrinsic is masked.

Reviewed By: kito-cheng

Differential Revision: https://reviews.llvm.org/D140662

diff --git a/clang/include/clang/Basic/riscv_vector.td b/clang/include/clang/Basic/riscv_vector.td
index 9c05d89..6e089a7 100644 (file)
--- a/clang/include/clang/Basic/riscv_vector.td
+++ b/clang/include/clang/Basic/riscv_vector.td
@@ -812,6 +812,80 @@ multiclass RVVIndexedStore<string op> {
 }
 
 defvar NFList = [2, 3, 4, 5, 6, 7, 8];
+/*
+A segment load builtin has different variants.
+
+Therefore a segment unit-stride load builtin can have 4 variants,
+1. When unmasked and the policies are all specified as agnostic:
+(Address0, ..., Address{NF - 1}, Ptr, VL)
+2. When masked and the policies are all specified as agnostic:
+(Address0, ..., Address{NF - 1}, Mask, Ptr, VL)
+3. When unmasked and one of the policies is specified as undisturbed:
+(Address0, ..., Address{NF - 1}, Maskedoff0, ..., Maskedoff{NF - 1},
+  Ptr, VL)
+4. When masked and one of the policies is specified as undisturbed:
+(Address0, ..., Address{NF - 1}, Mask, Maskedoff0, ..., Maskedoff{NF - 1},
+  Ptr, VL)
+
+Other variants of segment load builtin share the same structure, but they
+have their own extra parameter.
+
+The segment unit-stride fault-only-first load builtin has a 'NewVL'
+operand after the 'Ptr' operand.
+1. When unmasked and the policies are all specified as agnostic:
+(Address0, ..., Address{NF - 1}, Ptr, NewVL, VL)
+2. When masked and the policies are all specified as agnostic:
+(Address0, ..., Address{NF - 1}, Mask, Ptr, NewVL, VL)
+3. When unmasked and one of the policies is specified as undisturbed:
+(Address0, ..., Address{NF - 1}, Maskedoff0, ..., Maskedoff{NF - 1},
+  Ptr, NewVL, VL)
+4. When masked and one of the policies is specified as undisturbed:
+(Address0, ..., Address{NF - 1}, Mask, Maskedoff0, ..., Maskedoff{NF - 1},
+  Ptr, NewVL, VL)
+
+The segment strided load builtin has a 'Stride' operand after the 'Ptr'
+operand.
+1. When unmasked and the policies are all specified as agnostic:
+(Address0, ..., Address{NF - 1}, Ptr, Stride, VL)
+2. When masked and the policies are all specified as agnostic:
+(Address0, ..., Address{NF - 1}, Mask, Ptr, Stride, VL)
+3. When unmasked and one of the policies is specified as undisturbed:
+(Address0, ..., Address{NF - 1}, Maskedoff0, ..., Maskedoff{NF - 1},
+  Ptr, Stride, VL)
+4. When masked and one of the policies is specified as undisturbed:
+(Address0, ..., Address{NF - 1}, Mask, Maskedoff0, ..., Maskedoff{NF - 1},
+  Ptr, Stride, VL)
+
+The segment indexed load builtin has a 'Idx' operand after the 'Ptr' operand.
+1. When unmasked and the policies are all specified as agnostic:
+(Address0, ..., Address{NF - 1}, Ptr, Idx, VL)
+2. When masked and the policies are all specified as agnostic:
+(Address0, ..., Address{NF - 1}, Mask, Ptr, Idx, VL)
+3. When unmasked and one of the policies is specified as undisturbed:
+(Address0, ..., Address{NF - 1}, Maskedoff0, ..., Maskedoff{NF - 1},
+  Ptr, Idx, VL)
+4. When masked and one of the policies is specified as undisturbed:
+(Address0, ..., Address{NF - 1}, Mask, Maskedoff0, ..., Maskedoff{NF - 1},
+  Ptr, Idx, VL)
+
+Segment load intrinsics has different variants similar to their builtins.
+
+Segment unit-stride load intrinsic,
+  Masked: (Vector0, ..., Vector{NF - 1}, Ptr, Mask, VL, Policy)
+  Unmasked: (Vector0, ..., Vector{NF - 1}, Ptr, VL)
+Segment unit-stride fault-only-first load intrinsic,
+  Masked: (Vector0, ..., Vector{NF - 1}, Ptr, Mask, VL, Policy)
+  Unmasked: (Vector0, ..., Vector{NF - 1}, Ptr, VL)
+Segment strided load intrinsic,
+  Masked: (Vector0, ..., Vector{NF - 1}, Ptr, Stride, Mask, VL, Policy)
+  Unmasked: (Vector0, ..., Vector{NF - 1}, Ptr, Stride, VL)
+Segment indexed load intrinsic,
+  Masked: (Vector0, ..., Vector{NF - 1}, Ptr, Index, Mask, VL, Policy)
+  Unmasked: (Vector0, ..., Vector{NF - 1}, Ptr, Index, VL)
+
+The Vector(s) is poison when the policy behavior allows us to not care
+about any masked-off elements.
+*/
 
 class PVString<int nf, bit signed> {
   string S =
@@ -842,36 +916,30 @@ multiclass RVVUnitStridedSegLoad<string op> {
     {
       ResultType = ConvertType(E->getArg(0)->getType()->getPointeeType());
       IntrinsicTypes = {ResultType, Ops.back()->getType()};
-      SmallVector<llvm::Value*, 10> Operands;
-      if (IsMasked) {
-        // TAMA builtin: (val0 address, ..., mask, ptr, vl)
-        // builtin: (val0 address, ..., mask, maskedoff0, ..., ptr, vl)
-        // intrinsic: (maskedoff0, ..., ptr, mask, vl)
-        if (PolicyAttrs == TAIL_AGNOSTIC_MASK_AGNOSTIC) {
-          Operands.append(NF, llvm::PoisonValue::get(ResultType));
-          Operands.push_back(Ops[NF + 1]);
-          Operands.push_back(Ops[NF]);
-          Operands.push_back(Ops[NF + 2]);
-        } else {
+      SmallVector<llvm::Value*, 12> Operands;
+
+      // Please refer to comment under 'defvar NFList' in this file
+      if ((IsMasked && PolicyAttrs == TAIL_AGNOSTIC_MASK_AGNOSTIC) ||
+          (!IsMasked && PolicyAttrs == TAIL_AGNOSTIC))
+        Operands.append(NF, llvm::PoisonValue::get(ResultType));
+      else {
+        if (IsMasked)
           Operands.append(Ops.begin() + NF + 1, Ops.begin() + 2 * NF + 1);
-          Operands.push_back(Ops[2 * NF + 1]);
-          Operands.push_back(Ops[NF]);
-          Operands.push_back(Ops[2 * NF + 2]);
-        }
-        Operands.push_back(ConstantInt::get(Ops.back()->getType(), PolicyAttrs));
-        assert(Operands.size() == NF + 4);
-      } else {
-        // TA builtin: (val0 address, val1 address, ..., ptr, vl)
-        // TU builtin: (val0 address, ..., passthru0, ..., ptr, vl)
-        // intrinsic: (passthru0, passthru1, ..., ptr, vl)
-        if (PolicyAttrs == TAIL_AGNOSTIC) {
-          Operands.append(NF, llvm::PoisonValue::get(ResultType));
-          Operands.push_back(Ops[NF]);
-          Operands.push_back(Ops[NF + 1]);
-        } else {
-          Operands.append(Ops.begin() + NF, Ops.begin() + 2 * NF + 2);
-        }
+        else // Unmasked
+          Operands.append(Ops.begin() + NF, Ops.begin() + 2 * NF);
       }
+      unsigned PtrOperandIdx = IsMasked ?
+        (PolicyAttrs == TAIL_AGNOSTIC_MASK_AGNOSTIC) ? NF + 1 : 2 * NF + 1 :
+        (PolicyAttrs == TAIL_AGNOSTIC) ? NF : 2 * NF;
+      Value *PtrOperand = Ops[PtrOperandIdx];
+      Value *VLOperand = Ops[PtrOperandIdx + 1];
+      Operands.push_back(PtrOperand);
+      if (IsMasked)
+        Operands.push_back(Ops[NF]);
+      Operands.push_back(VLOperand);
+      if (IsMasked)
+        Operands.push_back(ConstantInt::get(Ops.back()->getType(), PolicyAttrs));
+
       llvm::Function *F = CGM.getIntrinsic(ID, IntrinsicTypes);
       llvm::Value *LoadValue = Builder.CreateCall(F, Operands, "");
       clang::CharUnits Align =
@@ -914,43 +982,30 @@ multiclass RVVUnitStridedSegLoadFF<string op> {
       ResultType = ConvertType(E->getArg(0)->getType()->getPointeeType());
       IntrinsicTypes = {ResultType, Ops.back()->getType()};
       SmallVector<llvm::Value*, 12> Operands;
-      Value *NewVL;
 
-      if (IsMasked) {
-        // TAMA builtin: (val0 address, ..., mask, ptr, new_vl, vl)
-        // builtin: (val0 address, ..., mask, maskedoff0, ..., ptr, new_vl, vl)
-        // intrinsic: (maskedoff0, ..., ptr, mask, vl)
-        if (PolicyAttrs == TAIL_AGNOSTIC_MASK_AGNOSTIC) {
-          Operands.append(NF, llvm::PoisonValue::get(ResultType));
-          Operands.push_back(Ops[NF + 1]);
-          Operands.push_back(Ops[NF]);
-          Operands.push_back(Ops[NF + 3]);
-          NewVL = Ops[NF + 2];
-        } else {
+      // Please refer to comment under 'defvar NFList' in this file
+      if ((IsMasked && PolicyAttrs == TAIL_AGNOSTIC_MASK_AGNOSTIC) ||
+          (!IsMasked && PolicyAttrs == TAIL_AGNOSTIC))
+        Operands.append(NF, llvm::PoisonValue::get(ResultType));
+      else {
+        if (IsMasked)
           Operands.append(Ops.begin() + NF + 1, Ops.begin() + 2 * NF + 1);
-          Operands.push_back(Ops[2 * NF + 1]);
-          Operands.push_back(Ops[NF]);
-          Operands.push_back(Ops[2 * NF + 3]);
-          NewVL = Ops[2 * NF + 2];
-        }
-        Operands.push_back(ConstantInt::get(Ops.back()->getType(), PolicyAttrs));
-        assert(Operands.size() == NF + 4);
-      } else {
-        // TA builtin: (val0 address, val1 address, ..., ptr, new_vl, vl)
-        // TU builtin: (val0 address, ..., passthru0, ..., ptr, new_vl, vl)
-        // intrinsic: (passthru0, passthru1, ..., ptr, vl)
-        if (PolicyAttrs == TAIL_AGNOSTIC) {
-          Operands.append(NF, llvm::PoisonValue::get(ResultType));
-          Operands.push_back(Ops[NF]);
-          Operands.push_back(Ops[NF + 2]);
-          NewVL = Ops[NF + 1];
-        } else {
+        else // Unmasked
           Operands.append(Ops.begin() + NF, Ops.begin() + 2 * NF);
-          Operands.push_back(Ops[2 * NF]);
-          Operands.push_back(Ops[2 * NF + 2]);
-          NewVL = Ops[2 * NF + 1];
-        }
       }
+      unsigned PtrOperandIdx = IsMasked ?
+        (PolicyAttrs == TAIL_AGNOSTIC_MASK_AGNOSTIC) ? NF + 1 : 2 * NF + 1 :
+        (PolicyAttrs == TAIL_AGNOSTIC) ? NF : 2 * NF;
+      Value *PtrOperand = Ops[PtrOperandIdx];
+      Value *NewVLOperand = Ops[PtrOperandIdx + 1];
+      Value *VLOperand = Ops[PtrOperandIdx + 2];
+      Operands.push_back(PtrOperand);
+      if (IsMasked)
+        Operands.push_back(Ops[NF]);
+      Operands.push_back(VLOperand);
+      if (IsMasked)
+        Operands.push_back(ConstantInt::get(Ops.back()->getType(), PolicyAttrs));
+
       llvm::Function *F = CGM.getIntrinsic(ID, IntrinsicTypes);
       llvm::Value *LoadValue = Builder.CreateCall(F, Operands, "");
       clang::CharUnits Align =
@@ -961,7 +1016,7 @@ multiclass RVVUnitStridedSegLoadFF<string op> {
       }
       // Store new_vl.
       llvm::Value *Val = Builder.CreateExtractValue(LoadValue, {NF});
-      return Builder.CreateStore(Val, Address(NewVL, Val->getType(), Align));
+      return Builder.CreateStore(Val, Address(NewVLOperand, Val->getType(), Align));
     }
     }] in {
           defvar PV = PVString<nf, /*signed=*/true>.S;
@@ -995,41 +1050,30 @@ multiclass RVVStridedSegLoad<string op> {
       IntrinsicTypes = {ResultType, Ops.back()->getType()};
       SmallVector<llvm::Value*, 12> Operands;
 
-      if (IsMasked) {
-        // TAMA builtin: (val0 address, ..., mask, ptr, stride, vl)
-        // builtin: (val0 address, ..., mask, maskedoff0, ..., ptr, stride, vl)
-        // intrinsic: (maskedoff0, ..., ptr, stride, mask, vl)
-        if (PolicyAttrs == TAIL_AGNOSTIC_MASK_AGNOSTIC) {
-          Operands.append(NF, llvm::PoisonValue::get(ResultType));
-          Operands.push_back(Ops[NF + 1]);
-          Operands.push_back(Ops[NF + 2]);
-          Operands.push_back(Ops[NF]);
-          Operands.push_back(Ops[NF + 3]);
-        } else {
+      // Please refer to comment under 'defvar NFList' in this file
+      if ((IsMasked && PolicyAttrs == TAIL_AGNOSTIC_MASK_AGNOSTIC) ||
+          (!IsMasked && PolicyAttrs == TAIL_AGNOSTIC))
+        Operands.append(NF, llvm::PoisonValue::get(ResultType));
+      else {
+        if (IsMasked)
           Operands.append(Ops.begin() + NF + 1, Ops.begin() + 2 * NF + 1);
-          Operands.push_back(Ops[2 * NF + 1]);
-          Operands.push_back(Ops[2 * NF + 2]);
-          Operands.push_back(Ops[NF]);
-          Operands.push_back(Ops[2 * NF + 3]);
-        }
-        Operands.push_back(ConstantInt::get(Ops.back()->getType(), PolicyAttrs));
-        assert(Operands.size() == NF + 5);
-      } else {
-        // TA builtin: (val0 address, val1 address, ..., ptr, stride, vl)
-        // TU builtin: (val0 address, ..., passthru0, ..., ptr, stride, vl)
-        // intrinsic: (passthru0, passthru1, ..., ptr, stride, vl)
-        if (PolicyAttrs == TAIL_AGNOSTIC) {
-          Operands.append(NF, llvm::PoisonValue::get(ResultType));
-          Operands.push_back(Ops[NF]);
-          Operands.push_back(Ops[NF + 1]);
-          Operands.push_back(Ops[NF + 2]);
-        } else {
+        else // Unmasked
           Operands.append(Ops.begin() + NF, Ops.begin() + 2 * NF);
-          Operands.push_back(Ops[2 * NF]);
-          Operands.push_back(Ops[2 * NF + 1]);
-          Operands.push_back(Ops[2 * NF + 2]);
-        }
       }
+      unsigned PtrOperandIdx = IsMasked ?
+        (PolicyAttrs == TAIL_AGNOSTIC_MASK_AGNOSTIC) ? NF + 1 : 2 * NF + 1 :
+        (PolicyAttrs == TAIL_AGNOSTIC) ? NF : 2 * NF;
+      Value *PtrOperand = Ops[PtrOperandIdx];
+      Value *StrideOperand = Ops[PtrOperandIdx + 1];
+      Value *VLOperand = Ops[PtrOperandIdx + 2];
+      Operands.push_back(PtrOperand);
+      Operands.push_back(StrideOperand);
+      if (IsMasked)
+        Operands.push_back(Ops[NF]);
+      Operands.push_back(VLOperand);
+      if (IsMasked)
+        Operands.push_back(ConstantInt::get(Ops.back()->getType(), PolicyAttrs));
+
       llvm::Function *F = CGM.getIntrinsic(ID, IntrinsicTypes);
       llvm::Value *LoadValue = Builder.CreateCall(F, Operands, "");
       clang::CharUnits Align =
@@ -1067,45 +1111,32 @@ multiclass RVVIndexedSegLoad<string op> {
     {
       ResultType = ConvertType(E->getArg(0)->getType()->getPointeeType());
       SmallVector<llvm::Value*, 12> Operands;
-      if (IsMasked) {
-        // TAMA builtin: (val0 address, ..., mask, ptr, index, vl)
-        // builtin: (val0 address, ..., mask, maskedoff0, ..., ptr, index, vl)
-        // intrinsic: (maskedoff0, ..., ptr, index, mask, vl)
-        if (PolicyAttrs == TAIL_AGNOSTIC_MASK_AGNOSTIC) {
-          Operands.append(NF, llvm::PoisonValue::get(ResultType));
-          Operands.push_back(Ops[NF + 1]);
-          Operands.push_back(Ops[NF + 2]);
-          Operands.push_back(Ops[NF]);
-          Operands.push_back(Ops[NF + 3]);
-          IntrinsicTypes = {ResultType, Ops[NF + 2]->getType(), Ops.back()->getType()};
-        } else {
+
+      // Please refer to comment under 'defvar NFList' in this file
+      if ((IsMasked && PolicyAttrs == TAIL_AGNOSTIC_MASK_AGNOSTIC) ||
+          (!IsMasked && PolicyAttrs == TAIL_AGNOSTIC))
+        Operands.append(NF, llvm::PoisonValue::get(ResultType));
+      else {
+        if (IsMasked)
           Operands.append(Ops.begin() + NF + 1, Ops.begin() + 2 * NF + 1);
-          Operands.push_back(Ops[2 * NF + 1]);
-          Operands.push_back(Ops[2 * NF + 2]);
-          Operands.push_back(Ops[NF]);
-          Operands.push_back(Ops[2 * NF + 3]);
-          IntrinsicTypes = {ResultType, Ops[2 * NF + 2]->getType(), Ops.back()->getType()};
-        }
-        Operands.push_back(ConstantInt::get(Ops.back()->getType(), PolicyAttrs));
-        assert(Operands.size() == NF + 5);
-      } else {
-        // TA builtin: (val0 address, val1 address, ..., ptr, index, vl)
-        // TU builtin: (val0 address, ..., passthru0, ..., ptr, index, vl)
-        // intrinsic: (passthru0, passthru1, ..., ptr, index, vl)
-        if (PolicyAttrs == TAIL_AGNOSTIC) {
-          Operands.append(NF, llvm::PoisonValue::get(ResultType));
-          Operands.push_back(Ops[NF]);
-          Operands.push_back(Ops[NF + 1]);
-          Operands.push_back(Ops[NF + 2]);
-          IntrinsicTypes = {ResultType, Ops[NF + 1]->getType(), Ops.back()->getType()};
-        } else {
+        else // Unmasked
           Operands.append(Ops.begin() + NF, Ops.begin() + 2 * NF);
-          Operands.push_back(Ops[2 * NF]);
-          Operands.push_back(Ops[2 * NF + 1]);
-          Operands.push_back(Ops[2 * NF + 2]);
-          IntrinsicTypes = {ResultType, Ops[2 * NF + 1]->getType(), Ops.back()->getType()};
-        }
       }
+      unsigned PtrOperandIdx = IsMasked ?
+        (PolicyAttrs == TAIL_AGNOSTIC_MASK_AGNOSTIC) ? NF + 1 : 2 * NF + 1 :
+        (PolicyAttrs == TAIL_AGNOSTIC) ? NF : 2 * NF;
+      Value *PtrOperand = Ops[PtrOperandIdx];
+      Value *IndexOperand = Ops[PtrOperandIdx + 1];
+      Value *VLOperand = Ops[PtrOperandIdx + 2];
+      Operands.push_back(PtrOperand);
+      Operands.push_back(IndexOperand);
+      if (IsMasked)
+        Operands.push_back(Ops[NF]);
+      Operands.push_back(VLOperand);
+      if (IsMasked)
+        Operands.push_back(ConstantInt::get(Ops.back()->getType(), PolicyAttrs));
+      IntrinsicTypes = {ResultType, IndexOperand->getType(), Ops.back()->getType()};
+
       llvm::Function *F = CGM.getIntrinsic(ID, IntrinsicTypes);
       llvm::Value *LoadValue = Builder.CreateCall(F, Operands, "");
       clang::CharUnits Align =