[RISCV] Add isel patterns for vmacc, vnmsac.

The patch selects VSELECT/VP_MERGE_VL which uses fmadd/fnmsub as true operand
and the adden of the fmadd/fnmsub as false operand.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D135330

Author: Yeting Kuo

llvm/lib/Target/RISCV/RISCVInstrInfoVVLPatterns.td

@@ -284,6 +284,20 @@ def SDTRVVVecReduce : SDTypeProfile<1, 5, [
   SDTCVecEltisVT<4, i1>, SDTCisSameNumEltsAs<2, 4>, SDTCisVT<5, XLenVT>
 ]>;
 
+def riscv_add_vl_oneuse : PatFrag<(ops node:$A, node:$B, node:$C, node:$D,
+                                       node:$E),
+                                  (riscv_add_vl node:$A, node:$B, node:$C,
+                                                node:$D, node:$E), [{
+  return N->hasOneUse();
+}]>;
+
+def riscv_sub_vl_oneuse : PatFrag<(ops node:$A, node:$B, node:$C, node:$D,
+                                       node:$E),
+                                  (riscv_sub_vl node:$A, node:$B, node:$C,
+                                                node:$D, node:$E), [{
+  return N->hasOneUse();
+}]>;
+
 def riscv_mul_vl_oneuse : PatFrag<(ops node:$A, node:$B, node:$C, node:$D,
                                        node:$E),
                                   (riscv_mul_vl node:$A, node:$B, node:$C,
@@ -1010,6 +1024,66 @@ multiclass VPatMultiplyAddVL_VV_VX<SDNode op, string instruction_name> {
   }
 }
 
+multiclass VPatMultiplyAccVL_VV_VX<PatFrag op, string instruction_name> {
+  foreach vti = AllIntegerVectors in {
+  defvar suffix = vti.LMul.MX;
+  def : Pat<(riscv_vp_merge_vl (vti.Mask true_mask),
+              (vti.Vector (op vti.RegClass:$rd,
+                              (riscv_mul_vl_oneuse vti.RegClass:$rs1, vti.RegClass:$rs2,
+                                  srcvalue, (vti.Mask true_mask), VLOpFrag),
+                              srcvalue, (vti.Mask true_mask), VLOpFrag)),
+                          vti.RegClass:$rd, VLOpFrag),
+            (!cast<Instruction>(instruction_name#"_VV_"# suffix)
+                 vti.RegClass:$rd, vti.RegClass:$rs1, vti.RegClass:$rs2,
+                 GPR:$vl, vti.Log2SEW, TAIL_UNDISTURBED_MASK_UNDISTURBED)>;
+  def : Pat<(riscv_vp_merge_vl (vti.Mask V0),
+              (vti.Vector (op vti.RegClass:$rd,
+                              (riscv_mul_vl_oneuse vti.RegClass:$rs1, vti.RegClass:$rs2,
+                                  srcvalue, (vti.Mask true_mask), VLOpFrag),
+                              srcvalue, (vti.Mask true_mask), VLOpFrag)),
+                          vti.RegClass:$rd, VLOpFrag),
+            (!cast<Instruction>(instruction_name#"_VV_"# suffix #"_MASK")
+                 vti.RegClass:$rd, vti.RegClass:$rs1, vti.RegClass:$rs2,
+                 (vti.Mask V0), GPR:$vl, vti.Log2SEW, TAIL_UNDISTURBED_MASK_UNDISTURBED)>;
+  def : Pat<(riscv_vp_merge_vl (vti.Mask true_mask),
+              (vti.Vector (op vti.RegClass:$rd,
+                              (riscv_mul_vl_oneuse (SplatPat XLenVT:$rs1), vti.RegClass:$rs2,
+                                  srcvalue, (vti.Mask true_mask), VLOpFrag),
+                              srcvalue, (vti.Mask true_mask), VLOpFrag)),
+                          vti.RegClass:$rd, VLOpFrag),
+            (!cast<Instruction>(instruction_name#"_VX_"# suffix)
+                 vti.RegClass:$rd, vti.ScalarRegClass:$rs1, vti.RegClass:$rs2,
+                 GPR:$vl, vti.Log2SEW, TAIL_UNDISTURBED_MASK_UNDISTURBED)>;
+  def : Pat<(riscv_vp_merge_vl (vti.Mask V0),
+              (vti.Vector (op vti.RegClass:$rd,
+                              (riscv_mul_vl_oneuse (SplatPat XLenVT:$rs1), vti.RegClass:$rs2,
+                                  srcvalue, (vti.Mask true_mask), VLOpFrag),
+                              srcvalue, (vti.Mask true_mask), VLOpFrag)),
+                          vti.RegClass:$rd, VLOpFrag),
+            (!cast<Instruction>(instruction_name#"_VX_"# suffix #"_MASK")
+                 vti.RegClass:$rd, vti.ScalarRegClass:$rs1, vti.RegClass:$rs2,
+                 (vti.Mask V0), GPR:$vl, vti.Log2SEW, TAIL_UNDISTURBED_MASK_UNDISTURBED)>;
+  def : Pat<(riscv_vselect_vl (vti.Mask V0),
+              (vti.Vector (op vti.RegClass:$rd,
+                              (riscv_mul_vl_oneuse vti.RegClass:$rs1, vti.RegClass:$rs2,
+                                  srcvalue, (vti.Mask true_mask), VLOpFrag),
+                              srcvalue, (vti.Mask true_mask), VLOpFrag)),
+                          vti.RegClass:$rd, VLOpFrag),
+            (!cast<Instruction>(instruction_name#"_VV_"# suffix #"_MASK")
+                 vti.RegClass:$rd, vti.RegClass:$rs1, vti.RegClass:$rs2,
+                 (vti.Mask V0), GPR:$vl, vti.Log2SEW, TAIL_AGNOSTIC)>;
+  def : Pat<(riscv_vselect_vl (vti.Mask V0),
+              (vti.Vector (op vti.RegClass:$rd,
+                              (riscv_mul_vl_oneuse (SplatPat XLenVT:$rs1), vti.RegClass:$rs2,
+                                  srcvalue, (vti.Mask true_mask), VLOpFrag),
+                              srcvalue, (vti.Mask true_mask), VLOpFrag)),
+                          vti.RegClass:$rd, VLOpFrag),
+            (!cast<Instruction>(instruction_name#"_VX_"# suffix #"_MASK")
+                 vti.RegClass:$rd, vti.ScalarRegClass:$rs1, vti.RegClass:$rs2,
+                 (vti.Mask V0), GPR:$vl, vti.Log2SEW, TAIL_AGNOSTIC)>;
+  }
+}
+
 multiclass VPatWidenMultiplyAddVL_VV_VX<PatFrag op1, string instruction_name> {
   foreach vtiTowti = AllWidenableIntVectors in {
     defvar vti = vtiTowti.Vti;
@@ -1315,6 +1389,8 @@ defm : VPatBinaryWVL_VV_VX<riscv_vwmulsu_vl, "PseudoVWMULSU">;
 // 12.13 Vector Single-Width Integer Multiply-Add Instructions
 defm : VPatMultiplyAddVL_VV_VX<riscv_add_vl, "PseudoVMADD">;
 defm : VPatMultiplyAddVL_VV_VX<riscv_sub_vl, "PseudoVNMSUB">;
+defm : VPatMultiplyAccVL_VV_VX<riscv_add_vl_oneuse, "PseudoVMACC">;
+defm : VPatMultiplyAccVL_VV_VX<riscv_sub_vl_oneuse, "PseudoVNMSAC">;
 
 // 12.14. Vector Widening Integer Multiply-Add Instructions
 defm : VPatWidenMultiplyAddVL_VV_VX<riscv_vwmul_vl_oneuse, "PseudoVWMACC">;