[llvm] [X86][MC] Support encoding/decoding for APX variant ADD/SUB/ADC/SBB/OR/XOR instructions (PR #76319)

[Phoebe Wang via llvm-commits]

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@@ -523,56 +606,200 @@ multiclass ArithBinOp_RF<bits<8> BaseOpc, bits<8> BaseOpc2, bits<8> BaseOpc4,
                          SDNode opnodeflag, SDNode opnode,
                          bit CommutableRR, bit ConvertibleToThreeAddress,
                          bit ConvertibleToThreeAddressRR> {
-  let Constraints = "$src1 = $dst" in {
-    let isCommutable = CommutableRR,
-        isConvertibleToThreeAddress = ConvertibleToThreeAddressRR in {
+  let isCommutable = CommutableRR,
+      isConvertibleToThreeAddress = ConvertibleToThreeAddressRR in {
+    let Predicates = [NoNDD] in {
     def NAME#8rr  : BinOpRR_RF<BaseOpc, mnemonic, Xi8 , opnodeflag>;
     def NAME#16rr : BinOpRR_RF<BaseOpc, mnemonic, Xi16, opnodeflag>, OpSize16;
     def NAME#32rr : BinOpRR_RF<BaseOpc, mnemonic, Xi32, opnodeflag>, OpSize32;
     def NAME#64rr : BinOpRR_RF<BaseOpc, mnemonic, Xi64, opnodeflag>;
     }
+    let Predicates = [HasNDD, In64BitMode] in {
+    def NAME#8rr_ND  : BinOpRR_RF<BaseOpc, mnemonic, Xi8 , opnodeflag, 1>;
+    def NAME#16rr_ND : BinOpRR_RF<BaseOpc, mnemonic, Xi16, opnodeflag, 1>, PD;
+    def NAME#32rr_ND : BinOpRR_RF<BaseOpc, mnemonic, Xi32, opnodeflag, 1>;
+    def NAME#64rr_ND : BinOpRR_RF<BaseOpc, mnemonic, Xi64, opnodeflag, 1>;
+    def NAME#8rr_NF_ND  : BinOpRR_R<BaseOpc, mnemonic, Xi8, 1>, EVEX_NF;
+    def NAME#16rr_NF_ND : BinOpRR_R<BaseOpc, mnemonic, Xi16, 1>, EVEX_NF, PD;
+    def NAME#32rr_NF_ND : BinOpRR_R<BaseOpc, mnemonic, Xi32, 1>, EVEX_NF;
+    def NAME#64rr_NF_ND : BinOpRR_R<BaseOpc, mnemonic, Xi64, 1>, EVEX_NF;
+    }
+    let Predicates = [In64BitMode] in {
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phoebewang wrote:

Why need `In64BitMode` but no `HasNF`?

https://github.com/llvm/llvm-project/pull/76319