1 files changed, 80 insertions, 0 deletions
diff --git a/js/src/gdb/mozilla/Interpreter.py b/js/src/gdb/mozilla/Interpreter.py
new file mode 100644
index 000000000..e54210e79
--- /dev/null
+++ b/js/src/gdb/mozilla/Interpreter.py
@@ -0,0 +1,80 @@
+# Pretty-printers for InterpreterRegs.
+
+import gdb
+import mozilla.prettyprinters as prettyprinters
+
+prettyprinters.clear_module_printers(__name__)
+
+from mozilla.prettyprinters import pretty_printer
+
+# Cache information about the Interpreter types for this objfile.
+class InterpreterTypeCache(object):
+    def __init__(self):
+        self.tValue = gdb.lookup_type('JS::Value')
+        self.tJSOp = gdb.lookup_type('JSOp')
+        self.tScriptFrameIterData = gdb.lookup_type('js::ScriptFrameIter::Data')
+        self.tInterpreterFrame = gdb.lookup_type('js::InterpreterFrame')
+        self.tBaselineFrame = gdb.lookup_type('js::jit::BaselineFrame')
+        self.tRematerializedFrame = gdb.lookup_type('js::jit::RematerializedFrame')
+
+@pretty_printer('js::InterpreterRegs')
+class InterpreterRegs(object):
+    def __init__(self, value, cache):
+        self.value = value
+        self.cache = cache
+        if not cache.mod_Interpreter:
+            cache.mod_Interpreter = InterpreterTypeCache()
+        self.itc = cache.mod_Interpreter
+
+    # There's basically no way to co-operate with 'set print pretty' (how would
+    # you get the current level of indentation?), so we don't even bother
+    # trying. No 'children', just 'to_string'.
+    def to_string(self):
+        fp_ = 'fp_ = {}'.format(self.value['fp_'])
+        slots = (self.value['fp_'] + 1).cast(self.itc.tValue.pointer())
+        sp = 'sp = fp_.slots() + {}'.format(self.value['sp'] - slots)
+        pc = self.value['pc']
+        try:
+            opcode = pc.dereference().cast(self.itc.tJSOp)
+        except:
+            opcode = 'bad pc'
+        pc = 'pc = {} ({})'.format(pc.cast(self.cache.void_ptr_t), opcode)
+        return '{{ {}, {}, {} }}'.format(fp_, sp, pc)
+
+@pretty_printer('js::AbstractFramePtr')
+class AbstractFramePtr(object):
+    Tag_ScriptFrameIterData = 0x0
+    Tag_InterpreterFrame = 0x1
+    Tag_BaselineFrame = 0x2
+    Tag_RematerializedFrame = 0x3
+    TagMask = 0x3
+
+    def __init__(self, value, cache):
+        self.value = value
+        self.cache = cache
+        if not cache.mod_Interpreter:
+            cache.mod_Interpreter = InterpreterTypeCache()
+        self.itc = cache.mod_Interpreter
+
+    def to_string(self):
+        ptr = self.value['ptr_']
+        tag = ptr & AbstractFramePtr.TagMask
+        ptr = ptr & ~AbstractFramePtr.TagMask
+        if tag == AbstractFramePtr.Tag_ScriptFrameIterData:
+            label = 'js::ScriptFrameIter::Data'
+            ptr = ptr.cast(self.itc.tScriptFrameIterData.pointer())
+        if tag == AbstractFramePtr.Tag_InterpreterFrame:
+            label = 'js::InterpreterFrame'
+            ptr = ptr.cast(self.itc.tInterpreterFrame.pointer())
+        if tag == AbstractFramePtr.Tag_BaselineFrame:
+            label = 'js::jit::BaselineFrame'
+            ptr = ptr.cast(self.itc.tBaselineFrame.pointer())
+        if tag == AbstractFramePtr.Tag_RematerializedFrame:
+            label = 'js::jit::RematerializedFrame'
+            ptr = ptr.cast(self.itc.tRematerializedFrame.pointer())
+        return 'AbstractFramePtr (({} *) {})'.format(label, ptr)
+
+    # Provide the ptr_ field as a child, so it prints after the pretty string
+    # provided above.
+    def children(self):
+        yield ('ptr_', self.value['ptr_'])