[llvm] [Xtensa] Implement base CallConvention. (PR #83280)

[Sergei Barannikov via llvm-commits]

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@@ -238,6 +239,11 @@ def L32R : RI16_Inst<0x01, (outs AR:$t), (ins L32Rtarget:$label),
   let imm16 = label;
 }
 
+//extending loads
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s-barannikov wrote:

It is very difficult indeed. I left some comments and will revisit once they are addressed.


https://github.com/llvm/llvm-project/pull/83280