[Driver] Inject the MSVC compatibility version into the triple

Encoding the version into the triple will allow us to communicate to
LLVM what functions it can expect to depend upon in the implementation.

llvm-svn: 239273

1 files changed, 50 insertions, 30 deletions

diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index a53cfa22660..a03bb33aa4f 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -2584,6 +2584,53 @@ static void appendUserToPath(SmallVectorImpl<char> &Result) {
   Result.append(UID.begin(), UID.end());
 }
 
+VersionTuple visualstudio::getMSVCVersion(const Driver *D,
+                                          const llvm::Triple &Triple,
+                                          const llvm::opt::ArgList &Args,
+                                          bool IsWindowsMSVC) {
+  if (Args.hasFlag(options::OPT_fms_extensions, options::OPT_fno_ms_extensions,
+                   IsWindowsMSVC) ||
+      Args.hasArg(options::OPT_fmsc_version) ||
+      Args.hasArg(options::OPT_fms_compatibility_version)) {
+    const Arg *MSCVersion = Args.getLastArg(options::OPT_fmsc_version);
+    const Arg *MSCompatibilityVersion =
+      Args.getLastArg(options::OPT_fms_compatibility_version);
+
+    if (MSCVersion && MSCompatibilityVersion) {
+      if (D)
+        D->Diag(diag::err_drv_argument_not_allowed_with)
+            << MSCVersion->getAsString(Args)
+            << MSCompatibilityVersion->getAsString(Args);
+      return VersionTuple();
+    }
+
+    if (MSCompatibilityVersion) {
+      VersionTuple MSVT;
+      if (MSVT.tryParse(MSCompatibilityVersion->getValue()) && D)
+        D->Diag(diag::err_drv_invalid_value)
+            << MSCompatibilityVersion->getAsString(Args)
+            << MSCompatibilityVersion->getValue();
+      return MSVT;
+    }
+
+    if (MSCVersion) {
+      unsigned Version = 0;
+      if (StringRef(MSCVersion->getValue()).getAsInteger(10, Version) && D)
+        D->Diag(diag::err_drv_invalid_value) << MSCVersion->getAsString(Args)
+                                             << MSCVersion->getValue();
+      return getMSCompatibilityVersion(Version);
+    }
+
+    unsigned Major, Minor, Micro;
+    Triple.getEnvironmentVersion(Major, Minor, Micro);
+    if (Major || Minor || Micro)
+      return VersionTuple(Major, Minor, Micro);
+
+    return VersionTuple(18);
+  }
+  return VersionTuple();
+}
+
 void Clang::ConstructJob(Compilation &C, const JobAction &JA,
                          const InputInfo &Output,
                          const InputInfoList &Inputs,
@@ -4181,38 +4228,11 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
     CmdArgs.push_back("-fms-compatibility");
 
   // -fms-compatibility-version=18.00 is default.
-  VersionTuple MSVT;
-  if (Args.hasFlag(options::OPT_fms_extensions, options::OPT_fno_ms_extensions,
-                   IsWindowsMSVC) ||
-      Args.hasArg(options::OPT_fmsc_version) ||
-      Args.hasArg(options::OPT_fms_compatibility_version)) {
-    const Arg *MSCVersion = Args.getLastArg(options::OPT_fmsc_version);
-    const Arg *MSCompatibilityVersion =
-      Args.getLastArg(options::OPT_fms_compatibility_version);
-
-    if (MSCVersion && MSCompatibilityVersion)
-      D.Diag(diag::err_drv_argument_not_allowed_with)
-          << MSCVersion->getAsString(Args)
-          << MSCompatibilityVersion->getAsString(Args);
-
-    if (MSCompatibilityVersion) {
-      if (MSVT.tryParse(MSCompatibilityVersion->getValue()))
-        D.Diag(diag::err_drv_invalid_value)
-            << MSCompatibilityVersion->getAsString(Args)
-            << MSCompatibilityVersion->getValue();
-    } else if (MSCVersion) {
-      unsigned Version = 0;
-      if (StringRef(MSCVersion->getValue()).getAsInteger(10, Version))
-        D.Diag(diag::err_drv_invalid_value) << MSCVersion->getAsString(Args)
-                                            << MSCVersion->getValue();
-      MSVT = getMSCompatibilityVersion(Version);
-    } else {
-      MSVT = VersionTuple(18);
-    }
-
+  VersionTuple MSVT = visualstudio::getMSVCVersion(
+      &D, getToolChain().getTriple(), Args, IsWindowsMSVC);
+  if (!MSVT.empty())
     CmdArgs.push_back(
         Args.MakeArgString("-fms-compatibility-version=" + MSVT.getAsString()));
-  }
 
   bool IsMSVC2015Compatible = MSVT.getMajor() >= 19;
   if (ImplyVCPPCXXVer) {