Commit 8aba95d6 authored by Alex Bradbury's avatar Alex Bradbury
Browse files

[RISCV] Avoid signed integer overflow UB in RISCVMatInt::generateInstSeq 

Found by UBSan.

llvm-svn: 366398
parent ad73a436

llvm/lib/Target/RISCV/Utils/RISCVMatInt.cpp

+1 −1
Original line number Diff line number Diff line
@@ -64,7 +64,7 @@ void generateInstSeq(int64_t Val, bool IsRV64, InstSeq &Res) { 
  // performed when the recursion returns.



  int64_t Lo12 = SignExtend64<12>(Val);

  int64_t Hi52 = (Val + 0x800) >> 12;

  int64_t Hi52 = ((uint64_t)Val + 0x800ull) >> 12;

  int ShiftAmount = 12 + findFirstSet((uint64_t)Hi52);

  Hi52 = SignExtend64(Hi52 >> (ShiftAmount - 12), 64 - ShiftAmount);