Add unreachable instruction for switch statements with an unreachable default

5 files changed, 26 insertions, 3 deletions

diff --git a/binaryninjaapi.h b/binaryninjaapi.h
index bfa94d6f..8433b1d1 100644
--- a/binaryninjaapi.h
+++ b/binaryninjaapi.h
@@ -5016,6 +5016,7 @@ namespace BinaryNinja {
 		ExprId Jump(ExprId dest, const ILSourceLocation& loc = ILSourceLocation());
 		ExprId Return(const std::vector<ExprId>& sources, const ILSourceLocation& loc = ILSourceLocation());
 		ExprId NoReturn(const ILSourceLocation& loc = ILSourceLocation());
+		ExprId Unreachable(const ILSourceLocation& loc = ILSourceLocation());
 		ExprId Goto(uint64_t target, const ILSourceLocation& loc = ILSourceLocation());
 		ExprId Label(uint64_t target, const ILSourceLocation& loc = ILSourceLocation());
 		ExprId VarDeclare(const Variable& var, const ILSourceLocation& loc = ILSourceLocation());
diff --git a/binaryninjacore.h b/binaryninjacore.h
index 587e5920..fe5a984a 100644
--- a/binaryninjacore.h
+++ b/binaryninjacore.h
@@ -36,14 +36,14 @@
 // Current ABI version for linking to the core. This is incremented any time
 // there are changes to the API that affect linking, including new functions,
 // new types, or modifications to existing functions or types.
-#define BN_CURRENT_CORE_ABI_VERSION 21
+#define BN_CURRENT_CORE_ABI_VERSION 22
 
 // Minimum ABI version that is supported for loading of plugins. Plugins that
 // are linked to an ABI version less than this will not be able to load and
 // will require rebuilding. The minimum version is increased when there are
 // incompatible changes that break binary compatibility, such as changes to
 // existing types or functions.
-#define BN_MINIMUM_CORE_ABI_VERSION 20
+#define BN_MINIMUM_CORE_ABI_VERSION 22
 
 #ifdef __GNUC__
 	#ifdef BINARYNINJACORE_LIBRARY
@@ -1276,6 +1276,10 @@ extern "C"
 		HLIL_FCMP_O,
 		HLIL_FCMP_UO,
 
+		// Unreachable hint, typically used in switch statements that analysis knows
+		// has an unreachable default.
+		HLIL_UNREACHABLE,
+
 		// The following instructions are only used in SSA form
 		HLIL_WHILE_SSA,
 		HLIL_DO_WHILE_SSA,
diff --git a/highlevelilinstruction.cpp b/highlevelilinstruction.cpp
index 0e32673b..98c85ea2 100644
--- a/highlevelilinstruction.cpp
+++ b/highlevelilinstruction.cpp
@@ -66,7 +66,7 @@ unordered_map<HighLevelILOperandUsage, HighLevelILOperandType> HighLevelILInstru
 
 unordered_map<BNHighLevelILOperation, vector<HighLevelILOperandUsage>>
     HighLevelILInstructionBase::operationOperandUsage = {{HLIL_NOP, {}}, {HLIL_BREAK, {}}, {HLIL_CONTINUE, {}},
-        {HLIL_NORET, {}}, {HLIL_BP, {}}, {HLIL_UNDEF, {}}, {HLIL_UNIMPL, {}},
+        {HLIL_NORET, {}}, {HLIL_BP, {}}, {HLIL_UNDEF, {}}, {HLIL_UNIMPL, {}}, {HLIL_UNREACHABLE, {}},
         {HLIL_BLOCK, {BlockExprsHighLevelOperandUsage}},
         {HLIL_IF, {ConditionExprHighLevelOperandUsage, TrueExprHighLevelOperandUsage, FalseExprHighLevelOperandUsage}},
         {HLIL_WHILE, {ConditionExprHighLevelOperandUsage, LoopExprHighLevelOperandUsage}},
@@ -1371,6 +1371,8 @@ ExprId HighLevelILInstruction::CopyTo(
 		return dest->Return(params, *this);
 	case HLIL_NORET:
 		return dest->NoReturn(*this);
+	case HLIL_UNREACHABLE:
+		return dest->Unreachable(*this);
 	case HLIL_NEG:
 	case HLIL_NOT:
 	case HLIL_SX:
@@ -2451,6 +2453,12 @@ ExprId HighLevelILFunction::NoReturn(const ILSourceLocation& loc)
 }
 
 
+ExprId HighLevelILFunction::Unreachable(const ILSourceLocation& loc)
+{
+	return AddExprWithLocation(HLIL_UNREACHABLE, loc, 0);
+}
+
+
 ExprId HighLevelILFunction::Goto(uint64_t target, const ILSourceLocation& loc)
 {
 	return AddExprWithLocation(HLIL_GOTO, loc, 0, target);
diff --git a/highlevelilinstruction.h b/highlevelilinstruction.h
index 9cdb9b1a..97418100 100644
--- a/highlevelilinstruction.h
+++ b/highlevelilinstruction.h
@@ -1109,6 +1109,9 @@ namespace BinaryNinja
 	template <>
 	struct HighLevelILInstructionAccessor<HLIL_UNIMPL> : public HighLevelILInstructionBase
 	{};
+	template <>
+	struct HighLevelILInstructionAccessor<HLIL_UNREACHABLE> : public HighLevelILInstructionBase
+	{};
 
 	template <>
 	struct HighLevelILInstructionAccessor<HLIL_CONST> : public HighLevelILConstantInstruction
diff --git a/python/highlevelil.py b/python/highlevelil.py
index 942330bf..395de637 100644
--- a/python/highlevelil.py
+++ b/python/highlevelil.py
@@ -159,6 +159,7 @@ class HighLevelILInstruction(BaseILInstruction):
 	    HighLevelILOperation.HLIL_BREAK: [], HighLevelILOperation.HLIL_CONTINUE: [], HighLevelILOperation.HLIL_JUMP: [
 	        ("dest", "expr")
 	    ], HighLevelILOperation.HLIL_RET: [("src", "expr_list")], HighLevelILOperation.HLIL_NORET: [],
+	    HighLevelILOperation.HLIL_UNREACHABLE: [],
 	    HighLevelILOperation.HLIL_GOTO: [("target", "label")], HighLevelILOperation.HLIL_LABEL: [
 	        ("target", "label")
 	    ], HighLevelILOperation.HLIL_VAR_DECLARE: [("var", "var")], HighLevelILOperation.HLIL_VAR_INIT: [
@@ -1017,6 +1018,11 @@ class HighLevelILNoret(HighLevelILInstruction, Terminal):
 
 
 @dataclass(frozen=True, repr=False, eq=False)
+class HighLevelILUnreachable(HighLevelILInstruction, Terminal):
+	pass
+
+
+@dataclass(frozen=True, repr=False, eq=False)
 class HighLevelILGoto(HighLevelILInstruction, Terminal):
 	@property
 	def target(self) -> GotoLabel:
@@ -1937,6 +1943,7 @@ ILInstruction = {
     HighLevelILOperation.HLIL_JUMP: HighLevelILJump,  #  ("dest", "expr"),
     HighLevelILOperation.HLIL_RET: HighLevelILRet,  #  ("src", "expr_list"),
     HighLevelILOperation.HLIL_NORET: HighLevelILNoret,  #  ,
+    HighLevelILOperation.HLIL_UNREACHABLE: HighLevelILUnreachable,  #  ,
     HighLevelILOperation.HLIL_GOTO: HighLevelILGoto,  #  ("target", "label"),
     HighLevelILOperation.HLIL_LABEL: HighLevelILLabel,  #  ("target", "label"),
     HighLevelILOperation.HLIL_VAR_DECLARE: HighLevelILVarDeclare,  #  ("var", "var"),