[llvm] [RISCV] Initial codegen support for zvqdotq extension (PR #137039)

[Craig Topper via llvm-commits]

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@@ -26,3 +26,34 @@ let Predicates = [HasStdExtZvqdotq] in {
   def VQDOTSU_VX : VALUVX<0b101010, OPMVX, "vqdotsu.vx">;
   def VQDOTUS_VX : VALUVX<0b101110, OPMVX, "vqdotus.vx">;
 } // Predicates = [HasStdExtZvqdotq]
+
+
+def riscv_vqdot_vl : SDNode<"RISCVISD::VQDOT_VL", SDT_RISCVIntBinOp_VL>;
+def riscv_vqdotu_vl : SDNode<"RISCVISD::VQDOTU_VL", SDT_RISCVIntBinOp_VL>;
+def riscv_vqdotsu_vl : SDNode<"RISCVISD::VQDOTSU_VL", SDT_RISCVIntBinOp_VL>;
+
+multiclass VPseudoVQDOT_VV_VX {
+  foreach m = MxSet<32>.m in {
+    defm "" : VPseudoBinaryV_VV<m>,
+            SchedBinary<"WriteVIALUV", "ReadVIALUV", "ReadVIALUV", m.MX,
+                        forcePassthruRead=true>;
+    defm "" : VPseudoBinaryV_VX<m>,
+            SchedBinary<"WriteVIALUX", "ReadVIALUV", "ReadVIALUX", m.MX,
+                        forcePassthruRead=true>;
+  }
+}
+
+// TODO: Add pseudo and patterns for vqdotus.vx
+let Predicates = [HasStdExtZvqdotq], mayLoad = 0, mayStore = 0,
+    hasSideEffects = 0 in {
+  defm PseudoVQDOT : VPseudoVQDOT_VV_VX;
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topperc wrote:

Please add a FIXME to set isCommutable for VQDOT and VQDOTU. MachineCSE can use it, but it probably needs custom code and of course a test.

https://github.com/llvm/llvm-project/pull/137039