[llvm] [AMDGPU][GISel] Add RegBankLegalize support for G_SI_CALL (PR #165747)

[Chinmay Deshpande via llvm-commits]

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@@ -1146,6 +1148,12 @@ RegBankLegalizeRules::RegBankLegalizeRules(const GCNSubtarget &_ST,
 
   addRulesForGOpcs({G_AMDGPU_WAVE_ADDRESS}).Any({{UniP5}, {{SgprP5}, {}}});
 
+  addRulesForGOpcs({G_SI_CALL})
+      .Any({{_, UniP0}, {{None}, {SgprP0}}})
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chinmaydd wrote:

I did have to modify the definition of `G_SI_CALL` to take a virtual scalar register as an out value. But apart from that, I think I got the gist of what you were suggesting.

https://github.com/llvm/llvm-project/pull/165747