[TextAPI] Support more constructors for PackedVersions

TBD files now record minimum deplyoment versions and tapi interfaces
with apple system linker by a packed version encoding. Support mapping
between that and `VersionTuple`s.

Author: cyndyishida

llvm/include/llvm/TextAPI/PackedVersion.h

@@ -13,6 +13,7 @@
 #ifndef LLVM_TEXTAPI_PACKEDVERSION_H
 #define LLVM_TEXTAPI_PACKEDVERSION_H
 
+#include "llvm/Support/VersionTuple.h"
 #include <cstdint>
 #include <string>
 #include <utility>
@@ -28,10 +29,19 @@ class PackedVersion {
 
 public:
   constexpr PackedVersion() = default;
-  explicit constexpr PackedVersion(uint32_t RawVersion) : Version(RawVersion) {}
+  constexpr PackedVersion(uint32_t RawVersion) : Version(RawVersion) {}
   PackedVersion(unsigned Major, unsigned Minor, unsigned Subminor)
       : Version((Major << 16) | ((Minor & 0xff) << 8) | (Subminor & 0xff)) {}
 
+  PackedVersion(VersionTuple VT) {
+    unsigned Minor = 0, Subminor = 0;
+    if (auto VTMinor = VT.getMinor())
+      Minor = *VTMinor;
+    if (auto VTSub = VT.getSubminor())
+      Subminor = *VTSub;
+    *this = PackedVersion(VT.getMajor(), Minor, Subminor);
+  }
+
   bool empty() const { return Version == 0; }
 
   /// Retrieve the major version number.

llvm/lib/TextAPI/PackedVersion.cpp

@@ -28,7 +28,7 @@ bool PackedVersion::parse32(StringRef Str) {
   SmallVector<StringRef, 3> Parts;
   SplitString(Str, Parts, ".");
 
-  if (Parts.size() > 3)
+  if (Parts.size() > 3 || Parts.empty())
     return false;
 
   unsigned long long Num;
@@ -63,7 +63,7 @@ std::pair<bool, bool> PackedVersion::parse64(StringRef Str) {
   SmallVector<StringRef, 5> Parts;
   SplitString(Str, Parts, ".");
 
-  if (Parts.size() > 5)
+  if (Parts.size() > 5 || Parts.empty())
     return std::make_pair(false, Truncated);
 
   unsigned long long Num;

llvm/unittests/TextAPI/TextStubV5Tests.cpp

@@ -197,8 +197,18 @@ TEST(TBDv5, ReadFile) {
       Target(AK_arm64, PLATFORM_MACOS, VersionTuple(11, 0, 0)),
       Target(AK_arm64, PLATFORM_MACCATALYST, VersionTuple(14, 0)),
   };
+  std::set<Target> FileTargets{File->targets().begin(), File->targets().end()};
   EXPECT_EQ(mapToPlatformSet(AllTargets), File->getPlatforms());
   EXPECT_EQ(mapToArchitectureSet(AllTargets), File->getArchitectures());
+  EXPECT_EQ(FileTargets.size(), AllTargets.size());
+  for (const auto &Targ : AllTargets) {
+    auto FileTarg = FileTargets.find(Targ);
+    EXPECT_FALSE(FileTarg == FileTargets.end());
+    EXPECT_EQ(*FileTarg, Targ);
+    PackedVersion MD = Targ.MinDeployment;
+    PackedVersion FileMD = FileTarg->MinDeployment;
+    EXPECT_EQ(MD, FileMD);
+  }
 
   EXPECT_EQ(PackedVersion(1, 2, 0), File->getCurrentVersion());
   EXPECT_EQ(PackedVersion(1, 1, 0), File->getCompatibilityVersion());