[clang] [llvm] [dwarf] make dwarf fission compatible with RISCV relaxations (PR #164128)

[David Blaikie via llvm-commits]

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@@ -83,8 +83,24 @@ void MCSymbol::print(raw_ostream &OS, const MCAsmInfo *MAI) const {
   OS << '"';
 }
 
-#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
-LLVM_DUMP_METHOD void MCSymbol::dump() const {
-  dbgs() << *this;
+bool llvm::isRangeRelaxable(const MCSymbol *Begin, const MCSymbol *End) {
+  assert(Begin && "Range without a begin symbol?");
+  assert(End && "Range without an end symbol?");
+  llvm::SmallVector<const MCFragment *> RangeFragments{};
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dwblaikie wrote:

I'm not quite following - why is this vector needed? (rather than computing the `IsRelaxableRange` via a single iteration over the fragments in this loop below?

https://github.com/llvm/llvm-project/pull/164128