[clang] [clang] Enable descriptions for --print-supported-extensions (PR #66715)

[David Spickett via cfe-commits]

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@@ -1012,11 +1013,18 @@ TEST(TargetParserTest, getARMCPUForArch) {
 
 TEST(TargetParserTest, ARMPrintSupportedExtensions) {
   std::string expected = "All available -march extensions for ARM\n\n"
-                         "\tcrc\n\tcrypto\n\tsha2";
+                         "    Name                Description\n"
+                         "    crc                 This is a long dummy description\n"
+                         "    crypto              This is a long dummy description\n"
+                         "    sha2                This is a long dummy description\n";
+
+  llvm::StringMap<llvm::StringRef> DummyMap;
+  for (const auto &E : llvm::ARM::ARCHExtNames)
+    DummyMap.insert({E.Name, "This is a long dummy description"});
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DavidSpickett wrote:

Also it saves you adding a method to RISC-V just to get the list of extensions. Which we did for AArch64 but it was a hack there too that I would love to also remove one day.

https://github.com/llvm/llvm-project/pull/66715