[lldb] [llvm] [AArch64] move extension information into tablgen (PR #90987)

[Pavel Iliin via llvm-commits]

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@@ -426,30 +532,40 @@ def FeatureSpecRestrict : SubtargetFeature<"specrestrict", "HasSpecRestrict",
   "true", "Enable architectural speculation restriction (FEAT_CSV2_2)">;
 
 def FeatureSB : Extension<"sb", "SB",
-  "Enable v8.5 Speculation Barrier (FEAT_SB)" >;
+  "Enable v8.5 Speculation Barrier (FEAT_SB)", [],
+  "FEAT_SB", "+sb", 470>;
 
 def FeatureSSBS : Extension<"ssbs", "SSBS",
-  "Enable Speculative Store Bypass Safe bit (FEAT_SSBS, FEAT_SSBS2)" >;
+  "Enable Speculative Store Bypass Safe bit (FEAT_SSBS, FEAT_SSBS2)", [],
+  "FEAT_SSBS", "", 490>;
 
 def FeaturePredRes : Extension<"predres", "PredRes",
-  "Enable v8.5a execution and data prediction invalidation instructions (FEAT_SPECRES)" >;
+  "Enable v8.5a execution and data prediction invalidation instructions (FEAT_SPECRES)", [],
+  "FEAT_PREDRES", "+predres", 480>;
 
-def FeatureCacheDeepPersist : Extension<"ccdp", "CCDP",
+def FeatureCacheDeepPersist : SubtargetFeature<"ccdp", "CCDP", "true",
     "Enable v8.5 Cache Clean to Point of Deep Persistence (FEAT_DPB2)" >;
 
+// NOTE: BTI now has posfeat/negfeat, which it didn't before
+let ArchExtKindSpelling = "AEK_NONE" in
 def FeatureBranchTargetId : Extension<"bti", "BTI",
-    "Enable Branch Target Identification (FEAT_BTI)" >;
+    "Enable Branch Target Identification (FEAT_BTI)", [],
+    "FEAT_BTI", "+bti", 510>;
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ilinpv wrote:

Would it be possible to reserve for FMV features additional bit used to optimize or not to optimize feature in FMV resolver? I would address comments in https://github.com/llvm/llvm-project/pull/90928 having this bit set by default and by command line option.

https://github.com/llvm/llvm-project/pull/90987