[llvm] [X86] Added support for 16bit LEA instruction (PR #122102)

[Phoebe Wang via llvm-commits]

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@@ -25,6 +25,12 @@ let SchedRW = [WriteLEA] in {
                      [(set GR32:$dst, lea32addr:$src)]>,
                      OpSize32, Requires<[Not64BitMode]>;
 
+  def LEA64_16r : I<0x8D, MRMSrcMem, (outs GR16:$dst), (ins lea64_16mem:$src),
+                    "lea{w}\t{$src|$dst}, {$dst|$src}",
+                    [(set GR16:$dst, lea64_16addr:$src)]>,
+                  OpSize16,
+                  Requires<[In64BitMode]>;
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phoebewang wrote:

Is it possible not to define a new LEA64_16r, but add a pattern for 16-bit with LEA64_32r? This should address the encoding size concern.

https://github.com/llvm/llvm-project/pull/122102