[llvm] [X86] Fix optmasks handling for AVX10.1-256 (PR #73074)

[Evgenii Kudriashov via llvm-commits]

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@@ -3773,7 +3774,8 @@ static unsigned getLoadStoreRegOpcode(Register Reg,
     if (X86::RFP64RegClass.hasSubClassEq(RC))
       return Load ? X86::LD_Fp64m : X86::ST_Fp64m;
     if (X86::VK64RegClass.hasSubClassEq(RC)) {
-      assert(STI.hasBWI() && "KMOVQ requires BWI");
+      assert(STI.hasBWI() && STI.hasEVEX512() &&
+             "KMOVQ requires BWI with 512-bit vectors");
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e-kud wrote:

Done.

https://github.com/llvm/llvm-project/pull/73074