[llvm] [CodeGenPrepare] Replace deleted sext instr with the promoted value. (PR #71058)

[Florian Hahn via llvm-commits]

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@@ -2634,6 +2634,15 @@ struct ExtAddrMode : public TargetLowering::AddrMode {
   void print(raw_ostream &OS) const;
   void dump() const;
 
+  void replaceWith(Value *From, Value *To) {
+    if (BaseReg == From)
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fhahn wrote:

Are all cases below covered by the one new test?

https://github.com/llvm/llvm-project/pull/71058