[llvm] [X86][GlobalISel] Enable G_BUILD_VECTOR and G_CONSTANT_POOL (PR #92844)

[Matt Arsenault via llvm-commits]

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@@ -22,16 +22,22 @@ class X86Subtarget;
 class X86TargetMachine;
 
 class X86LegalizerInfo : public LegalizerInfo {
-private:
-  /// Keep a reference to the X86Subtarget around so that we can
-  /// make the right decision when generating code for different targets.
-  const X86Subtarget &Subtarget;
-
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arsenm wrote:

Leave this where it is? 

https://github.com/llvm/llvm-project/pull/92844