[llvm] [clang] [SystemZ][z/OS] This change adds support for the PPA2 section in zOS (PR #68926)

[Yusra Syeda via cfe-commits]

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@@ -976,6 +976,37 @@ void CodeGenModule::Release() {
       Context.getTypeSizeInChars(Context.getWideCharType()).getQuantity();
   getModule().addModuleFlag(llvm::Module::Error, "wchar_size", WCharWidth);
 
+  if (getTriple().isOSzOS()) {
+    getModule().addModuleFlag(llvm::Module::Warning,
+                              "zos_product_major_version",
+                              uint32_t(CLANG_VERSION_MAJOR));
+    getModule().addModuleFlag(llvm::Module::Warning,
+                              "zos_product_minor_version",
+                              uint32_t(CLANG_VERSION_MINOR));
+    getModule().addModuleFlag(llvm::Module::Warning, "zos_product_patchlevel",
+                              uint32_t(CLANG_VERSION_PATCHLEVEL));
+    std::string ProductId;
+#ifdef CLANG_VENDOR
+    ProductId = #CLANG_VENDOR;
+#else
+    ProductId = "clang";
+#endif
+    getModule().addModuleFlag(llvm::Module::Error, "zos_product_id",
+                              llvm::MDString::get(VMContext, ProductId));
+
+    // Record the language because we need it for the PPA2.
+    StringRef lang_str = languageToString(
+        LangStandard::getLangStandardForKind(LangOpts.LangStd).Language);
+    getModule().addModuleFlag(llvm::Module::Error, "zos_cu_language",
+                              llvm::MDString::get(VMContext, lang_str));
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ysyeda wrote:

We want to keep this as llvm::Module::Error. Merging of PPA2's is not defined (a limitation of the system). We will have some limitations with LTO in the future, e.g. mixing of C and C++, etc. will exclude the use of LTO. For now that should be fine.

https://github.com/llvm/llvm-project/pull/68926