Extend gdb-jit support (OSX/locals+parameters/prettyprint)

tools/gdb-v8-support.py

Index: tools/gdb-v8-support.py
diff --git a/tools/gdb-v8-support.py b/tools/gdb-v8-support.py
new file mode 100644
index 0000000000000000000000000000000000000000..0aa1d49467a65b7cddaec54d0f051544173c6ead
--- /dev/null
+++ b/tools/gdb-v8-support.py
@@ -0,0 +1,154 @@
+# Copyright 2011 the V8 project authors. All rights reserved.
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+#       copyright notice, this list of conditions and the following
+#       disclaimer in the documentation and/or other materials provided
+#       with the distribution.
+#     * Neither the name of Google Inc. nor the names of its
+#       contributors may be used to endorse or promote products derived
+#       from this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
+kSmiTag = 0
+kSmiTagSize = 1
+kSmiTagMask = (1 << kSmiTagSize) - 1
+
+
+kHeapObjectTag = 1
+kHeapObjectTagSize = 2
+kHeapObjectTagMask = (1 << kHeapObjectTagSize) - 1
+
+
+kFailureTag = 3
+kFailureTagSize = 2
+kFailureTagMask = (1 << kFailureTagSize) - 1
+
+
+kSmiShiftSize32 = 0
+kSmiValueSize32 = 31
+kSmiShiftBits32 = kSmiTagSize + kSmiShiftSize32
+
+
+kSmiShiftSize64 = 31
+kSmiValueSize64 = 32
+kSmiShiftBits64 = kSmiTagSize + kSmiShiftSize64
+
+
+kAllBits = 0xFFFFFFFF
+kTopBit32 = 0x80000000
+kTopBit64 = 0x8000000000000000
+
+
+t_u32 = gdb.lookup_type('unsigned int')
+t_u64 = gdb.lookup_type('unsigned long long')
+
+
+def has_smi_tag(v):
+  return v & kSmiTagMask == kSmiTag
+
+
+def has_failure_tag(v):
+  return v & kFailureTagMask == kFailureTag
+
+
+def has_heap_object_tag(v):
+  return v & kHeapObjectTagMask == kHeapObjectTag
+
+
+def raw_heap_object(v):
+  return v - kHeapObjectTag
+
+
+def smi_to_int_32(v):
+  v = v & kAllBits
+  if (v & kTopBit32) == kTopBit32:
+    return ((v & kAllBits) >> kSmiShiftBits32) - 2147483648
+  else:
+    return (v & kAllBits) >> kSmiShiftBits32
+
+
+def smi_to_int_64(v):
+  return (v >> kSmiShiftBits64)
+
+
+def decode_v8_value(v, bitness):
+  base_str = 'v8[%x]' % v
+  if has_smi_tag(v):
+    if bitness == 32:
+      return base_str + (" SMI(%d)" % smi_to_int_32(v))
+    else:
+      return base_str + (" SMI(%d)" % smi_to_int_64(v))
+  elif has_failure_tag(v):
+    return base_str + " (failure)"
+  elif has_heap_object_tag(v):
+    return base_str + (" H(0x%x)" % raw_heap_object(v))
+  else:
+    return base_str
+
+
+class V8ValuePrinter(object):
+  "Print a v8value."
+  def __init__(self, val):
+    self.val = val
+  def to_string(self):
+    if self.val.type.sizeof == 4:
+      v_u32 = self.val.cast(t_u32)
+      return decode_v8_value(int(v_u32), 32)
+    elif self.val.type.sizeof == 8:
+      v_u64 = self.val.cast(t_u64)
+      return decode_v8_value(int(v_u64), 64)
+    else:
+      return 'v8value?'
+  def display_hint(self):
+    return 'v8value'
+
+
+def v8_pretty_printers(val):
+  lookup_tag = val.type.tag
+  if lookup_tag == None:
+    return None
+  elif lookup_tag == 'v8value':
+    return V8ValuePrinter(val)
+  return None
+gdb.pretty_printers.append(v8_pretty_printers)
+
+
+def v8_to_int(v):
+  if v.type.sizeof == 4:
+    return int(v.cast(t_u32))
+  elif v.type.sizeof == 8:
+    return int(v.cast(t_u64))
+  else:
+    return '?'
+
+  
+def v8_get_value(vstring):
+  v = gdb.parse_and_eval(vstring)
+  return v8_to_int(v)
+
+
+class V8PrintObject (gdb.Command):
+  """Prints a v8 object."""
+  def __init__ (self):
+    super (V8PrintObject, self).__init__ ("v8print", gdb.COMMAND_DATA)
+  def invoke (self, arg, from_tty):
+    v = v8_get_value(arg)
+    gdb.execute('call __gdb_print_v8_object(%d)' % v)
+V8PrintObject()