Fixed a problem in the expression parser that

caused functions that were cast as part of the
call to have that cast ignored once their 
addresses were resolved.

Notably, in the case of objc_msgSend(), if
the function was cast from something returning
i8* to something returning i8, the expression
parser was discarding the cast as part of its
resolution.  This caused crashes later on.

llvm-svn: 136648

1 files changed, 28 insertions, 1 deletions

diff --git a/lldb/source/Expression/IRForTarget.cpp b/lldb/source/Expression/IRForTarget.cpp
index b5e5c561f75..af919a15f21 100644
--- a/lldb/source/Expression/IRForTarget.cpp
+++ b/lldb/source/Expression/IRForTarget.cpp
@@ -1408,6 +1408,8 @@ IRForTarget::MaybeHandleCall (CallInst *llvm_call_inst)
     lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
 
     Function *fun = llvm_call_inst->getCalledFunction();
+    
+    bool is_bitcast = false;
 
     // If the call is to something other than a plain llvm::Function, resolve which
     // Function is meant or give up.
@@ -1430,6 +1432,8 @@ IRForTarget::MaybeHandleCall (CallInst *llvm_call_inst)
             
                 return false;
             }
+            
+            is_bitcast = true;
         }
         else if (const_expr && const_expr->getOpcode() == Instruction::IntToPtr)
         {
@@ -1544,7 +1548,30 @@ IRForTarget::MaybeHandleCall (CallInst *llvm_call_inst)
     if (fun_value_ptr)
         fun_addr_ptr = *fun_value_ptr;
     
-    llvm_call_inst->setCalledFunction(fun_addr_ptr);
+    if (is_bitcast)
+    {
+        Value *val = llvm_call_inst->getCalledValue();
+        
+        ConstantExpr *const_expr = dyn_cast<ConstantExpr>(val);
+        
+        Constant *fun_addr_ptr_cst = dyn_cast<Constant>(fun_addr_ptr);
+        
+        if (!fun_addr_ptr_cst)
+        {
+            if (m_error_stream)
+                m_error_stream->Printf("Error [IRForTarget]: Non-constant source function '%s' has a constant BitCast\n", str.GetCString());
+            
+            return false;
+        }
+            
+        Constant *new_bit_cast = ConstantExpr::getBitCast(fun_addr_ptr_cst, const_expr->getType());
+        
+        llvm_call_inst->setCalledFunction(new_bit_cast);
+    }
+    else
+    {
+        llvm_call_inst->setCalledFunction(fun_addr_ptr);
+    }
     
     ConstantArray *func_name = (ConstantArray*)ConstantArray::get(m_module->getContext(), str.GetCString());