Merge pull request #4960 from diffblue/NathanJPhillips/feature/irep-pretty-printer

Add a pretty printer for irept

Author: NathanJPhillips

scripts/pretty-printers/gdb/pretty_printers.py

@@ -1,6 +1,43 @@
 import gdb
 
 
+def deconstruct_dstring(val):
+    # ideally, we want to access the memory where the string
+    # is stored directly instead of calling a function. However,
+    # this is simpler.
+    try:
+        raw_address = str(val.address)
+
+        # If it's ::empty, we know it's empty without going further.
+        if "::empty" in raw_address:
+            return -1, ""
+
+        # Split the address on the first space, return that value
+        # Addresses are usually {address} {optional type_name}
+        typed_pointer = "((const {} *){})".format(val.type, raw_address.split(None, 1)[0])
+
+        string_no = val["no"]
+
+        # Check that the pointer is not null.
+        null_ptr = gdb.parse_and_eval("{} == 0".format(typed_pointer))
+        if null_ptr.is_optimized_out:
+            return -1, "{}: <Ptr optimized out>".format(string_no)
+        if null_ptr:
+            return -1, ""
+
+        table_len = gdb.parse_and_eval("get_string_container().string_vector.size()")
+        if table_len.is_optimized_out:
+            return -1, "{}: <Table len optimized out>".format(string_no)
+        if string_no >= table_len:
+            return -1, "{} index ({}) out of range".format(val.type, string_no)
+
+        value = gdb.parse_and_eval("{}->c_str()".format(typed_pointer))
+        if value.is_optimized_out:
+            return -1, "{}: <Optimized out>".format(string_no)
+        return string_no, value.string().replace("\0", "")
+    except:
+        return -1, ""
+
 # Class for pretty-printing dstringt
 class DStringPrettyPrinter:
     "Print a dstringt"
@@ -9,44 +46,87 @@ def __init__(self, val):
         self.val = val
 
     def to_string(self):
-        # ideally, we want to access the memory where the string
-        # is stored directly instead of calling a function. However,
-        # this is simpler.
+        string_no, value = deconstruct_dstring(self.val)
+        if string_no == -1:
+            return value
+        return "{}: \"{}\"".format(string_no, value.replace("\"", "\\\""))
+
+    def display_hint(self):
+        return None
+
+
+def find_type(type, name):
+    type = type.strip_typedefs()
+    while True:
+        # Strip cv-qualifiers.
+        search = "%s::%s" % (type.unqualified(), name)
         try:
-            raw_address = str(self.val.address)
+            return gdb.lookup_type(search)
+        except RuntimeError:
+            pass
+        # The type was not found, so try the superclass.
+        # We only need to check the first superclass.
+        type = type.fields()[0].type
+
 
-            # If it's ::empty, we know it's empty without going further.
-            if "::empty" in raw_address:
-                return ""
-
-            # Split the address on the first space, return that value
-            # Addresses are usually {address} {optional type_name}
-            typed_pointer = "((const {} *){})".format(self.val.type, raw_address.split(None, 1)[0])
-
-            string_no = self.val["no"]
-
-            # Check that the pointer is not null.
-            null_ptr = gdb.parse_and_eval("{} == 0".format(typed_pointer))
-            if null_ptr.is_optimized_out:
-                return "{}: <Ptr optimized out>".format(string_no)
-            if null_ptr:
-                return ""
-
-            table_len = gdb.parse_and_eval("get_string_container().string_vector.size()")
-            if table_len.is_optimized_out:
-                return "{}: <Table len optimized out>".format(string_no)
-            if string_no >= table_len:
-                return "{} index ({}) out of range".format(self.val.type, string_no)
-
-            value = gdb.parse_and_eval("{}->c_str()".format(typed_pointer))
-            if value.is_optimized_out:
-                return "{}: <Optimized out>".format(string_no)
-            return "{}: \"{}\"".format(string_no, value.string().replace("\0", "").replace("\"", "\\\""))
+class IrepPrettyPrinter:
+    "Print an irept"
+
+    def __init__(self, val):
+        self.val = val["data"].referenced_value()
+
+    def to_string(self):
+        try:
+            return "\"{}\"".format(deconstruct_dstring(self.val["data"])[1].replace("\"", "\\\""))
         except:
-            return ""
+            return "Exception pretty printing irept"
+
+    def children(self):
+        sub = self.val["sub"]
+        count = 0
+        item = sub["_M_impl"]["_M_start"]
+        finish = sub["_M_impl"]["_M_finish"]
+        while item != finish:
+            yield "sub %d key" % count, "sub[%d]" % count
+            yield "sub %d value" % count, item.dereference()
+            count += 1
+            item += 1
+
+        named_sub = self.val["named_sub"]
+        size = named_sub["_M_t"]["_M_impl"]["_M_node_count"]
+        node = named_sub["_M_t"]["_M_impl"]["_M_header"]["_M_left"]
+        count = 0
+        while count != size:
+            rep_type = find_type(named_sub.type, "_Rep_type")
+            link_type = find_type(rep_type, "_Link_type")
+            node_type = link_type.strip_typedefs()
+            current = node.cast(node_type).dereference()
+            addr_type = current.type.template_argument(0).pointer()
+            result = current["_M_storage"]["_M_storage"].address.cast(addr_type).dereference()
+            yield "named_sub %d key" % count, "named_sub[\"%s\"]" % deconstruct_dstring(result["first"])[1].replace("\"", "\\\"")
+            yield "named_sub %d value" % count, result["second"]
+            count += 1
+            if count < size:
+                # Get the next node
+                right = node.dereference()["_M_right"]
+                if right:
+                    node = right
+                    while True:
+                        left = node.dereference()["_M_left"]
+                        if not left:
+                            break
+                        node = left
+                else:
+                    parent = node.dereference()["_M_parent"]
+                    while node == parent.dereference()["_M_right"]:
+                        node = parent
+                        parent = parent.dereference()["_M_parent"]
+                    # Not sure what this checks
+                    if node.dereference()["_M_right"] != parent:
+                        node = parent
 
     def display_hint(self):
-        return None
+        return "map"
 
 
 class InstructionPrettyPrinter: