[LoongArch] Don't left shift negative value (#106812)

Fixed another UB from #106332. Detected here https://lab.llvm.org/buildbot/#/builders/169/builds/2662
intel · Aug 31, 2024 · 18e35d8 · 18e35d8
1 parent 3745a2e
commit 18e35d8
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchMatInt.cpp b/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchMatInt.cpp
@@ -82,9 +82,9 @@ LoongArchMatInt::InstSeq LoongArchMatInt::generateInstSeq(int64_t Val) {
       TmpVal1 = Insts[1].Imm;
       if (N == 3)
         break;
-      TmpVal2 = Insts[3].Imm << 52 | TmpVal1;
+      TmpVal2 = static_cast<uint64_t>(Insts[3].Imm) << 52 | TmpVal1;
     }
-    TmpVal1 |= Insts[0].Imm << 12;
+    TmpVal1 |= static_cast<uint64_t>(Insts[0].Imm) << 12;
     break;
   case LoongArch::ORI:
   case LoongArch::ADDI_W: