From e43b80b633b494eb8b399cd51320b7b3bbe11eaf Mon Sep 17 00:00:00 2001
From: Fish <fish@cs.ucsb.edu>
Date: Fri, 14 Apr 2023 11:24:35 -0700
Subject: [PATCH] Separate parameters from local variables.

---
 cle/backends/elf/elf.py        | 7 +++++--
 cle/backends/elf/subprogram.py | 1 +
 cle/backends/elf/variable.py   | 3 +++
 3 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/cle/backends/elf/elf.py b/cle/backends/elf/elf.py
index e823a9ae..e91baa78 100644
--- a/cle/backends/elf/elf.py
+++ b/cle/backends/elf/elf.py
@@ -851,11 +851,14 @@ def _load_die_lex_block(
             block = LexicalBlock(low_pc, high_pc)
 
         for sub_die in cu.iter_DIE_children(die):
-            if sub_die.tag in ["DW_TAG_variable", "DW_TAG_formal_parameter"]:
+            if sub_die.tag in {"DW_TAG_variable", "DW_TAG_formal_parameter"}:
                 # load local variable
                 var = Variable.from_die(sub_die, expr_parser, self, dwarf, cu_low_pc, lexical_block=block)
                 var.decl_file = file_path
-                subprogram.local_variables.append(var)
+                if var.parameter:
+                    subprogram.parameters.append(var)
+                else:
+                    subprogram.local_variables.append(var)
             elif sub_die.tag == "DW_TAG_lexical_block":
                 sub_block = self._load_die_lex_block(
                     dwarf, sub_die, expr_parser, type_list, cu, file_path, cu_low_pc, subprogram
diff --git a/cle/backends/elf/subprogram.py b/cle/backends/elf/subprogram.py
index c784ca10..b997f3c4 100644
--- a/cle/backends/elf/subprogram.py
+++ b/cle/backends/elf/subprogram.py
@@ -47,3 +47,4 @@ def __init__(self, name, low_pc, high_pc) -> None:
         super().__init__(low_pc, high_pc)
         self.name = name
         self.local_variables: List[Variable] = []
+        self.parameters: List[Variable] = []
diff --git a/cle/backends/elf/variable.py b/cle/backends/elf/variable.py
index d413c620..91e84dda 100644
--- a/cle/backends/elf/variable.py
+++ b/cle/backends/elf/variable.py
@@ -65,6 +65,7 @@ class Variable:
         "external",
         "declaration_only",
         "_location",
+        "parameter",
     )
 
     def __init__(self, elf_object: "ELF"):
@@ -79,6 +80,7 @@ def __init__(self, elf_object: "ELF"):
         self.external = False
         self.declaration_only = False
         self._location: Optional[List[Tuple[int, int, Optional[VariableLocation]]]] = None
+        self.parameter: bool = False
 
     @staticmethod
     def from_die(
@@ -120,6 +122,7 @@ def from_die(
             var.external = True
         if "DW_AT_declaration" in die.attributes:
             var.declaration_only = True
+        var.parameter = die.tag == "DW_TAG_formal_parameter"
 
         var.lexical_block = lexical_block