Handle Z3 ITE expressions (#336)

* Add failing test * Print unrecognized Z3 expressions * Handle `ITE` Z3 expressions
lifting-bits · Apr 29, 2024 · 0de1db1 · 0de1db1
1 parent 86280f6
commit 0de1db1
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diff --git a/lib/AST/IRToASTVisitor.cpp b/lib/AST/IRToASTVisitor.cpp
@@ -139,8 +139,16 @@ clang::Expr *IRToASTVisitor::ConvertExpr(z3::expr expr) {
       CopyProvenance(sub, neg, dec_ctx.use_provenance);
       return neg;
     }
+    case Z3_OP_ITE: {
+      CHECK_EQ(expr.num_args(), 3)
+          << "Conditional expressions must have three arguments";
+      auto cond{ConvertExpr(expr.arg(0))};
+      auto tt{ConvertExpr(expr.arg(1))};
+      auto ff{ConvertExpr(expr.arg(2))};
+      return ast.CreateConditional(cond, tt, ff);
+    }
     default:
-      LOG(FATAL) << "Invalid z3 op";
+      LOG(FATAL) << "Invalid z3 op " << expr.to_string();
   }
   return nullptr;
 }

diff --git a/tests/tools/decomp/issue_335_z3_ite.ll b/tests/tools/decomp/issue_335_z3_ite.ll
@@ -0,0 +1,82 @@
+; ModuleID = '/sn640/NotDec/test/backend/../wasm/sysy/functional/32_while_if_test2.c'
+source_filename = "/sn640/NotDec/test/backend/../wasm/sysy/functional/32_while_if_test2.c"
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-pc-linux-gnu"
+
+; Function Attrs: noinline nounwind uwtable
+define dso_local i32 @ifWhile() #0 {
+  %1 = alloca i32, align 4
+  %2 = alloca i32, align 4
+  store i32 0, i32* %1, align 4
+  store i32 3, i32* %2, align 4
+  %3 = load i32, i32* %1, align 4
+  %4 = icmp eq i32 %3, 5
+  br i1 %4, label %5, label %15
+
+5:                                                ; preds = %0
+  br label %6
+
+6:                                                ; preds = %9, %5
+  %7 = load i32, i32* %2, align 4
+  %8 = icmp eq i32 %7, 2
+  br i1 %8, label %9, label %12
+
+9:                                                ; preds = %6
+  %10 = load i32, i32* %2, align 4
+  %11 = add nsw i32 %10, 2
+  store i32 %11, i32* %2, align 4
+  br label %6, !llvm.loop !6
+
+12:                                               ; preds = %6
+  %13 = load i32, i32* %2, align 4
+  %14 = add nsw i32 %13, 25
+  store i32 %14, i32* %2, align 4
+  br label %25
+
+15:                                               ; preds = %0
+  br label %16
+
+16:                                               ; preds = %19, %15
+  %17 = load i32, i32* %1, align 4
+  %18 = icmp slt i32 %17, 5
+  br i1 %18, label %19, label %24
+
+19:                                               ; preds = %16
+  %20 = load i32, i32* %2, align 4
+  %21 = mul nsw i32 %20, 2
+  store i32 %21, i32* %2, align 4
+  %22 = load i32, i32* %1, align 4
+  %23 = add nsw i32 %22, 1
+  store i32 %23, i32* %1, align 4
+  br label %16, !llvm.loop !8
+
+24:                                               ; preds = %16
+  br label %25
+
+25:                                               ; preds = %24, %12
+  %26 = load i32, i32* %2, align 4
+  ret i32 %26
+}
+
+; Function Attrs: noinline nounwind uwtable
+define dso_local i32 @main() #0 {
+  %1 = alloca i32, align 4
+  store i32 0, i32* %1, align 4
+  %2 = call i32 @ifWhile()
+  ret i32 %2
+}
+
+attributes #0 = { noinline nounwind uwtable "frame-pointer"="all" "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+
+!llvm.module.flags = !{!0, !1, !2, !3, !4}
+!llvm.ident = !{!5}
+
+!0 = !{i32 1, !"wchar_size", i32 4}
+!1 = !{i32 7, !"PIC Level", i32 2}
+!2 = !{i32 7, !"PIE Level", i32 2}
+!3 = !{i32 7, !"uwtable", i32 1}
+!4 = !{i32 7, !"frame-pointer", i32 2}
+!5 = !{!"Ubuntu clang version 14.0.0-1ubuntu1.1"}
+!6 = distinct !{!6, !7}
+!7 = !{!"llvm.loop.mustprogress"}
+!8 = distinct !{!8, !7}