[llvm] [RISCV] Add groupid/bitmask for RISC-V extension (PR #94440)

[Craig Topper via llvm-commits]

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@@ -210,10 +211,58 @@ static void emitRISCVProcs(RecordKeeper &RK, raw_ostream &OS) {
   OS << "\n#undef TUNE_PROC\n";
 }
 
+static inline uint64_t getValueFromBitsInit(const BitsInit *B,
+                                            const Record &R) {
+  assert(B->getNumBits() <= sizeof(uint64_t) * 8 && "BitInits' too long!");
+
+  uint64_t Value = 0;
+  for (unsigned i = 0, e = B->getNumBits(); i != e; ++i) {
+    const auto *Bit = dyn_cast<BitInit>(B->getBit(i));
+    if (Bit)
+      Value |= uint64_t(Bit->getValue()) << i;
+  }
+  return Value;
+}
+
+static void emitRISCVExtensionBitmask(RecordKeeper &RK, raw_ostream &OS) {
+
+  std::vector<Record *> Extensions =
+      RK.getAllDerivedDefinitionsIfDefined("RISCVExtensionBitmask");
+  llvm::sort(Extensions, [](const Record *Rec1, const Record *Rec2) {
+    return getExtensionName(Rec1) < getExtensionName(Rec2);
+  });
+
+  llvm::DenseSet<std::pair<uint64_t, uint64_t>> Seen;
+
+  OS << "#ifdef GET_RISCVExtensionBitmaskTable_IMPL\n";
+  OS << "static const RISCVExtensionBitmask ExtensionBitmask[]={\n";
+  for (const Record *Rec : Extensions) {
+    BitsInit *GroupIDBits = Rec->getValueAsBitsInit("GroupID");
+    BitsInit *BitmaskBits = Rec->getValueAsBitsInit("Bitmask");
+
+    StringRef ExtName = Rec->getValueAsString("Name");
+    ExtName.consume_front("experimental-");
+    uint64_t GroupIDVal = getValueFromBitsInit(GroupIDBits, *Rec);
+    uint64_t BitmaskVal = getValueFromBitsInit(BitmaskBits, *Rec);
+
+    assert(!Seen.contains(std::make_pair(GroupIDVal, BitmaskVal)) &&
+           "duplicated bitmask");
+    Seen.insert(std::make_pair(GroupIDVal, BitmaskVal));
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topperc wrote:

Use the return value from insert for the assert?

https://github.com/llvm/llvm-project/pull/94440