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

[Evgenii Kudriashov 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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e-kud wrote:

Yes. I've taken a look at `LegalizerInfo` and `AArch64LegalizerInfo`, they have private fields at the end of declaration. That's the reason I've decided it needs refactor. Apparently there is no strict rules about it. So, I've left it untouched.

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