[llvm][TextAPI] Handle implicitly upgraded deployment versions

Sometimes the clang driver will receive a target triple where the
deployment version is too low to support the platform + arch. In those
cases, the compiler upgrades the final minOS which is what gets recorded
ultimately by the linker in LC_BUILD_VERSION. TextAPI should also reuse
this logic for capturing minOS in recorded TBDv5 files.

Reviewed By: ributzka

Differential Revision: https://reviews.llvm.org/D145690

2 files changed, 11 insertions, 2 deletions

diff --git a/llvm/lib/TextAPI/Platform.cpp b/llvm/lib/TextAPI/Platform.cpp
index 673fcb7..a432462 100644
--- a/llvm/lib/TextAPI/Platform.cpp
+++ b/llvm/lib/TextAPI/Platform.cpp
@@ -132,5 +132,12 @@ std::string getOSAndEnvironmentName(PlatformType Platform,
   llvm_unreachable("Unknown llvm::MachO::PlatformType enum");
 }
 
+VersionTuple mapToSupportedOSVersion(const Triple &Triple) {
+  const VersionTuple MinSupportedOS = Triple.getMinimumSupportedOSVersion();
+  if (MinSupportedOS > Triple.getOSVersion())
+    return MinSupportedOS;
+  return Triple.getOSVersion();
+}
+
 } // end namespace MachO.
 } // end namespace llvm.
diff --git a/llvm/lib/TextAPI/TextStubV5.cpp b/llvm/lib/TextAPI/TextStubV5.cpp
index a9355fab..ade4c86 100644
--- a/llvm/lib/TextAPI/TextStubV5.cpp
+++ b/llvm/lib/TextAPI/TextStubV5.cpp
@@ -293,8 +293,10 @@ Expected<TargetList> getTargetsSection(const Object *Section) {
     if (!TargetOrErr)
       return make_error<JSONStubError>(getParseErrorMsg(TBDKey::Target));
     TargetOrErr->MinDeployment = Version;
-
-    IFTargets.push_back(*TargetOrErr);
+    // Convert to LLVM::Triple to accurately compute minOS + platform + arch
+    // pairing.
+    IFTargets.push_back(
+        MachO::Target(Triple(getTargetTripleName(*TargetOrErr))));
   }
   return std::move(IFTargets);
 }