[llvm-dev] Swift to IR, generates wrong IR

Rinaldini Julien via llvm-dev llvm-dev at lists.llvm.org
Mon Oct 5 02:25:58 PDT 2015

I have a simple swift code from which I generate IR code with ‘swiftc test.swift -emit-ir -o test.ll'
When I try to run the .ll file or apply optimization with opt, I get errors like this one: 

lli: test.ll:548:110: error: expected instruction opcode
  %9 = cmpxchg i64* bitcast (%swift.type*** @field_type_vector_TipCalculator to i64*), i64 0, i64 %8 seq_cst seq_cst
I know swift is not part of the LLVM oss project, but is this problem coming from swift generating wrong IR code or is this a LLVM bug (or maybe I’m just doing something wrong)?


ps: this is the swift code I try running: 

class TipCalculator {

  // 2
  let total: Double
    let taxPct: Double
    let subtotal: Double

    // 3
    init(total: Double, taxPct: Double) {a
      self.total = total
        self.taxPct = taxPct 
        subtotal = total / (taxPct + 1)

  // 4
  func calcTipWithTipPct(tipPct: Double) -> Double {a
    return subtotal * tipPct

  // 5
  func printPossibleTips() {
    print("15%: \(calcTipWithTipPct(0.15))")
      print("18%: \(calcTipWithTipPct(0.18))")
      print("20%: \(calcTipWithTipPct(0.20))")


// 6
let tipCalc = TipCalculator(total: 33.25, taxPct: 0.06)

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