[clang] [clang][ExtractAPI] Record availability information only for the target platform (PR #76823)

[Sofía Rodríguez via cfe-commits]

https://github.com/sofiaromorales created https://github.com/llvm/llvm-project/pull/76823

Currently, ExtractAPI provides availability information for all platforms within a given domain. With this change, we narrow down the output to include availability details only for the specified target platform, so users can generate the symbol graph with only the availability information they need, omitting information of the other platforms.

This change reverts the functionality introduced in [`57c9780`](https://github.com/llvm/llvm-project/commit/57c9780).

rdar://120419037


>From d459421cc3a59f56c27eaeafd81ec2c2366b9fa7 Mon Sep 17 00:00:00 2001
From: Sofia Rodriguez <sofia_rodriguez at apple.com>
Date: Wed, 3 Jan 2024 15:29:45 +0100
Subject: [PATCH] [clang][ExtractAPI] Record availability information only for
 the target platform.

Currently, ExtractAPI provides availability information for all platforms within a given domain.
With this change, we narrow down the output to include availability details only for the specified target platform,
so users can generate the symbol graph with only the availability information they need, omitting information of the other platforms.

This change reverts the functionality introduced in `57c9780`.
---
 clang/lib/ExtractAPI/AvailabilityInfo.cpp |  8 ++++++++
 clang/test/ExtractAPI/availability.c      | 20 --------------------
 2 files changed, 8 insertions(+), 20 deletions(-)

diff --git a/clang/lib/ExtractAPI/AvailabilityInfo.cpp b/clang/lib/ExtractAPI/AvailabilityInfo.cpp
index 1df852fdbf9304..0c578de227ade1 100644
--- a/clang/lib/ExtractAPI/AvailabilityInfo.cpp
+++ b/clang/lib/ExtractAPI/AvailabilityInfo.cpp
@@ -1,11 +1,17 @@
 #include "clang/ExtractAPI/AvailabilityInfo.h"
 #include "clang/AST/Attr.h"
 #include "llvm/ADT/STLExtras.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/Basic/TargetInfo.h"
 
 using namespace clang;
 using namespace extractapi;
 
 AvailabilitySet::AvailabilitySet(const Decl *Decl) {
+    
+  ASTContext &Context = Decl->getASTContext();
+  StringRef PlatformName = Context.getTargetInfo().getPlatformName();
+    
   // Collect availability attributes from all redeclrations.
   for (const auto *RD : Decl->redecls()) {
     if (const auto *A = RD->getAttr<UnavailableAttr>()) {
@@ -24,6 +30,8 @@ AvailabilitySet::AvailabilitySet(const Decl *Decl) {
 
     for (const auto *Attr : RD->specific_attrs<AvailabilityAttr>()) {
       StringRef Domain = Attr->getPlatform()->getName();
+      if (Domain != PlatformName)
+        continue;
       auto *Availability =
           llvm::find_if(Availabilities, [Domain](const AvailabilityInfo &Info) {
             return Domain.equals(Info.Domain);
diff --git a/clang/test/ExtractAPI/availability.c b/clang/test/ExtractAPI/availability.c
index 4bda94ba7c2bf9..3c1ef5c45b634d 100644
--- a/clang/test/ExtractAPI/availability.c
+++ b/clang/test/ExtractAPI/availability.c
@@ -300,22 +300,6 @@ void e(void) __attribute__((availability(tvos, unavailable)));
             "minor": 0,
             "patch": 0
           }
-        },
-        {
-          "domain": "ios",
-          "introduced": {
-            "major": 13,
-            "minor": 0,
-            "patch": 0
-          }
-        },
-        {
-          "domain": "tvos",
-          "introduced": {
-            "major": 15,
-            "minor": 0,
-            "patch": 0
-          }
         }
       ],
       "declarationFragments": [
@@ -394,10 +378,6 @@ void e(void) __attribute__((availability(tvos, unavailable)));
             "minor": 0,
             "patch": 0
           }
-        },
-        {
-          "domain": "tvos",
-          "isUnconditionallyUnavailable": true
         }
       ],
       "declarationFragments": [