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

[Craig Topper via llvm-commits]

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@@ -210,10 +211,61 @@ 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::DenseMap<std::pair<uint64_t, uint64_t>, bool> Seen;
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topperc wrote:

Use DenseSet

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