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

[Ulrich Weigand via cfe-commits]

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@@ -1026,6 +1030,78 @@ void SystemZAsmPrinter::emitADASection() {
   OutStreamer->popSection();
 }
 
+static uint32_t getProductVersion(Module &M) {
+  if (auto *VersionVal = cast_or_null<ConstantAsMetadata>(
+          M.getModuleFlag("zos_product_major_version")))
+    return cast<ConstantInt>(VersionVal->getValue())->getZExtValue();
+  return LLVM_VERSION_MAJOR;
+}
+
+static uint32_t getProductRelease(Module &M) {
+  if (auto *ReleaseVal = cast_or_null<ConstantAsMetadata>(
+          M.getModuleFlag("zos_product_minor_version")))
+    return cast<ConstantInt>(ReleaseVal->getValue())->getZExtValue();
+  return LLVM_VERSION_MINOR;
+}
+
+static uint32_t getProductPatch(Module &M) {
+  if (auto *PatchVal = cast_or_null<ConstantAsMetadata>(
+          M.getModuleFlag("zos_product_patchlevel")))
+    return cast<ConstantInt>(PatchVal->getValue())->getZExtValue();
+  return LLVM_VERSION_PATCH;
+}
+
+static time_t getTranslationTime(Module &M) {
+  std::time_t Time = 0;
+  if (auto *Val = cast_or_null<ConstantAsMetadata>(
+          M.getModuleFlag("zos_translation_time"))) {
+    long SecondsSinceEpoch = cast<ConstantInt>(Val->getValue())->getSExtValue();
+    Time = static_cast<time_t>(SecondsSinceEpoch);
+  }
+  return Time;
+}
+
+void SystemZAsmPrinter::emitIDRLSection(Module &M) {
+  OutStreamer->pushSection();
+  OutStreamer->switchSection(getObjFileLowering().getIDRLSection());
+  constexpr unsigned IDRLDataLength = 30;
+  std::time_t Time = getTranslationTime(M);
+
+  uint32_t ProductVersion = getProductVersion(M);
+  uint32_t ProductRelease = getProductRelease(M);
+
+  std::string ProductID;
+  if (auto *MD = M.getModuleFlag("zos_product_id"))
+    ProductID = cast<MDString>(MD)->getString().str();
+
+  if (ProductID.empty()) {
+    char ProductIDFormatted[11]; // 10 + null.
+    snprintf(ProductIDFormatted, sizeof(ProductIDFormatted), "LLVM  %02d%02d",
+             ProductVersion, ProductRelease);
+    ProductID = ProductIDFormatted;
+  }
+
+  // Remove - from Product Id, which makes it consistent with legacy.
+  // The binder expects alphanumeric characters only.
+  std::size_t DashFound = ProductID.find("-");
+  if (DashFound != std::string::npos)
+    ProductID.erase(ProductID.begin() + DashFound);
+
+  SmallString<IDRLDataLength + 1> TempStr;
+  raw_svector_ostream O(TempStr);
+  O << formatv("{0}{1,0-2:d}{2,0-2:d}{3:%Y-%m-%d %H:%M:%S}", ProductID.c_str(),
+               ProductVersion, ProductRelease, llvm::sys::toUtcTime(Time));
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uweigand wrote:

Can this overflow?  In the default case above, you ensure the ProductID has 10 bytes.  But in the case where the ID comes from the IR, its length can be anything, and is not checked here.

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