add bltl (#254)

translator/src/Translator.Core/Lifting/PpcLifter.cs

@@ -1942,6 +1942,22 @@ public sealed partial class PpcLifter
                     new IrCall(string.Empty, TargetLabel(ins, validAddresses, preferFallthrough: false), blArgs) 
                 };
 
+            case "bltl":
+                {
+                    var crField = "cr0";
+                    if (ops.Count > 0 && ops[0] is PpcConditionRegisterOperand crOp)
+                    {
+                        crField = NormalizeRegister(crOp.Name);
+                    }
+
+                    return new IrInstruction[]
+                    {
+                        new IrAssign("lr", IrValue.Imm((int)ins.EndAddress)),
+                        new IrBranch("blt", TargetLabel(ins, validAddresses, preferFallthrough: false),
+                            $"0x{ins.EndAddress:X8}", crField)
+                    };
+                }
+
             case "bcl":
                 {
                     var rawInstr = ReadRawInstruction(ins);

translator/tests/Translator.Tests/PpcLifterAdditionalCoverageTests.cs

@@ -14,6 +14,23 @@ public class PpcLifterAdditionalCoverageTests
     private static PpcInstruction Instruction(uint raw, string mnemonic, params PpcOperand[] operands)
         => PpcInstruction.Synthetic(0x80000000, raw, mnemonic, operands);
 
+    [Fact]
+    public void LinkedConditionalBranchSetsLrBeforeEitherPath()
+    {
+        var branch = PpcDecoder.Decode(0x80004394, 0x41800029);
+        var ir = Assert.Single(new PpcLifter().Lift(new[] { branch })).Ir;
+
+        Assert.Equal("bltl", branch.Mnemonic);
+        var lr = Assert.IsType<IrAssign>(ir[0]);
+        Assert.Equal("lr", lr.Destination);
+        Assert.Equal(unchecked((int)0x80004398u), lr.Value.Constant);
+
+        var decision = Assert.IsType<IrBranch>(ir[1]);
+        Assert.Equal("blt", decision.Condition);
+        Assert.Equal("0x800043BC", decision.TrueLabel);
+        Assert.Equal("0x80004398", decision.FalseLabel);
+    }
+
     [Fact]
     public void LiftsAdditionalNonDotArithmeticAndLogicalForms()
     {