[clang] [llvm] [TargetParser] Parse Intel GPU architecture names, and use the list in clang (PR #223199)

[Srividya Sundaram via llvm-commits]

================
@@ -63,3 +73,110 @@ std::string llvm::IntelGPU::getNumericArchName(uint32_t GPUIPVersion) {
   return ("xe_" + Twine(Major) + "." + Twine(Minor) + "." + Twine(Revision))
       .str();
 }
+
+StringRef llvm::IntelGPU::getArchName(GPUKind Kind) {
+  switch (Kind) {
+  case GK_NONE:
+    return "";
+#define INTEL_GPU(NAME, KIND, MAJOR, MINOR, IGCA_TARGET, IGCA_FEATURE_SETS)    \
+  case GK_##KIND:                                                              \
+    return NAME;
+#define INTEL_GPU_COMPAT(NAME, KIND, IGCA_TARGET, IGCA_FEATURE_SETS)           \
+  case GK_##KIND:                                                              \
+    return NAME;
+#include "llvm/TargetParser/IntelGPUTargetParser.def"
+  }
+  llvm_unreachable("invalid Intel GPU GPUKind");
+}
+
+// Read a numeric architecture name, e.g. "xe_12.60.7", into the GPU IP version
+// it spells. The revision may be omitted, since it takes no part in a lookup
+// either way. Anything else is not a numeric name, which is not the same as
+// naming no device: a caller distinguishes the two by whether this succeeds.
+static bool parseNumericArchName(StringRef Name, uint32_t &GPUIPVersion) {
+  if (!Name.consume_front("xe_"))
+    return false;
+
+  StringRef MajorStr, MinorStr, RevisionStr;
+  std::tie(MajorStr, Name) = Name.split('.');
+  std::tie(MinorStr, RevisionStr) = Name.split('.');
+  uint32_t Major, Minor, Revision = 0;
+  if (MajorStr.getAsInteger(10, Major) || MinorStr.getAsInteger(10, Minor))
+    return false;
+  if (!RevisionStr.empty() && RevisionStr.getAsInteger(10, Revision))
+    return false;
+
+  // A field too wide for the GPU IP version it spells describes no GPU that
+  // could ever report it, so this is not a numeric name rather than one naming
+  // no device.
+  if (Major > GPUIPMajorMask || Minor > GPUIPMinorMask ||
+      Revision > GPUIPRevisionMask)
+    return false;
+  GPUIPVersion = packDevice(Major, Minor) | Revision;
+  return true;
+}
+
+GPUKind llvm::IntelGPU::parseArch(StringRef Name) {
+  GPUKind Kind = StringSwitch<GPUKind>(Name)
+#define INTEL_GPU(NAME, KIND, MAJOR, MINOR, IGCA_TARGET, IGCA_FEATURE_SETS)    \
+  .Case(NAME, GK_##KIND)
+#define INTEL_GPU_COMPAT(NAME, KIND, IGCA_TARGET, IGCA_FEATURE_SETS)           \
+  .Case(NAME, GK_##KIND)
+#define INTEL_GPU_ALIAS(NAME, KIND) .Case(NAME, GK_##KIND)
+#include "llvm/TargetParser/IntelGPUTargetParser.def"
+                     .Default(GK_NONE);
+  if (Kind != GK_NONE)
+    return Kind;
+
+  // A device with no human-friendly name is spelled numerically, so the same
+  // lookup the driver does for a reported GPU IP version has to be reachable by
+  // name.
+  uint32_t GPUIPVersion;
+  if (parseNumericArchName(Name, GPUIPVersion))
+    return getKindForVersion(GPUIPVersion);
----------------
srividya-sundaram wrote:

Currently, a device the list doesn't know, is rejected on purpose with` "unsupported offload gpu architecture"`, since there's no `IGCA target` or `ocloc` name to use for it. 

https://github.com/llvm/llvm-project/pull/223199