<html>
<head>
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
</head>
<body bgcolor="#FFFFFF" text="#000000">
<p>I think flag_present and implicit_const attributes shouldn't be
treated as similar here: flag_present attributes physically do
have a record in .debug_info section, while implicit_const
attributes are not physically mentioned there. Printing
implicit_const values when dumping .debug_info can be more
convenient for reader but it will actually violate the definition
of dump. When dumping section contents we expect to see what is
actually there, don't we?<br>
</p>
<br>
<div class="moz-cite-prefix">On 02/27/2017 09:04 PM, David Blaikie
wrote:<br>
</div>
<blockquote
cite="mid:CAENS6Evjji0hdLPQhZiMD6+T9LJm_y4oCBi=Stc_5ESbvaJSZg@mail.gmail.com"
type="cite">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<div dir="ltr"><br>
<br>
<div class="gmail_quote">
<div dir="ltr">On Mon, Feb 27, 2017 at 10:00 AM Victor Leschuk
<<a moz-do-not-send="true"
href="mailto:vleschuk@accesssoftek.com">vleschuk@accesssoftek.com</a>>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000" class="gmail_msg">
<p class="gmail_msg"><br class="gmail_msg">
</p>
<br class="gmail_msg">
<div class="m_-7636712434836838175moz-cite-prefix
gmail_msg">On 02/27/2017 08:04 PM, David Blaikie wrote:<br
class="gmail_msg">
</div>
<blockquote type="cite" class="gmail_msg">
<div dir="ltr" class="gmail_msg">Skipping these values
doesn't seem to be correct - in the case of
flag_present, I think the value is still rendered in
the dump, is it not?</div>
</blockquote>
</div>
<div bgcolor="#FFFFFF" text="#000000" class="gmail_msg"> Do
you mean that the value is somehow mentioned in
.debug_info section? It is not.</div>
</blockquote>
<div><br>
Looks to me like it is:<br>
<br>
dumping debug info for this code: void f1() { }<br>
<br>
produces this:<br>
<br>
<font face="monospace"> .debug_abbrev contents:<br>
...<br>
</font>
<div><font face="monospace"> [2] DW_TAG_subprogram
DW_CHILDREN_no</font></div>
<div><font face="monospace"> ...</font></div>
<div><font face="monospace"> DW_AT_external
DW_FORM_flag_present<br>
<br>
.debug_info contents:<br>
...<br>
0x0000002a: DW_TAG_subprogram [2]<br>
...<br>
DW_AT_external [DW_FORM_flag_present]
(true)</font></div>
<br>
</div>
<div>I would expect similar behavior for const_value - that
the attribute and its constant value is printed in the
debug_info dump.<br>
<br>
</div>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000" class="gmail_msg"><br
class="gmail_msg">
<blockquote type="cite" class="gmail_msg">
<div dir="ltr" class="gmail_msg"> I would expect the
same for implicit_const values. (also, this needs test
coverage either way)</div>
</blockquote>
</div>
<div bgcolor="#FFFFFF" text="#000000" class="gmail_msg">
Yes, you are correct. I will create tests when we decide
what's right behavior here. <br class="gmail_msg">
<br class="gmail_msg">
I think skipping is correct here: we are dumping
.debug_info data based on attributes stored in AbbrevDecl,
this code was based on assumption that every attribute has
representation in .debug_info section, that was before
implicit_const form was introduced.</div>
<div bgcolor="#FFFFFF" text="#000000" class="gmail_msg"><br
class="gmail_msg">
<blockquote type="cite" class="gmail_msg"><br
class="gmail_msg">
<div class="gmail_quote gmail_msg">
<div dir="ltr" class="gmail_msg">On Sat, Feb 25, 2017
at 5:27 AM Victor Leschuk via llvm-commits <<a
moz-do-not-send="true"
href="mailto:llvm-commits@lists.llvm.org"
class="gmail_msg" target="_blank">llvm-commits@lists.llvm.org</a>>
wrote:<br class="gmail_msg">
</div>
<blockquote class="gmail_quote gmail_msg"
style="margin:0 0 0 .8ex;border-left:1px #ccc
solid;padding-left:1ex">Author: vleschuk<br
class="gmail_msg">
Date: Sat Feb 25 07:15:57 2017<br class="gmail_msg">
New Revision: 296253<br class="gmail_msg">
<br class="gmail_msg">
URL: <a moz-do-not-send="true"
href="http://llvm.org/viewvc/llvm-project?rev=296253&view=rev"
rel="noreferrer" class="gmail_msg" target="_blank">http://llvm.org/viewvc/llvm-project?rev=296253&view=rev</a><br
class="gmail_msg">
Log:<br class="gmail_msg">
[DebugInfo] Skip implicit_const attributes when
dumping .debug_info. NFC.<br class="gmail_msg">
<br class="gmail_msg">
When dumping .debug_info section we loop through all
attributes mentioned in<br class="gmail_msg">
.debug_abbrev section and dump values using
DWARFFormValue::extractValue().<br class="gmail_msg">
We need to skip implicit_const attributes here as
their values are not<br class="gmail_msg">
really located in .debug_info but directly in
.debug_abbrev. This patch fixes<br class="gmail_msg">
triggered assert() in DWARFFormValue::extractValue()
caused by trying to<br class="gmail_msg">
access implicit_const values from .debug_info.<br
class="gmail_msg">
<br class="gmail_msg">
Modified:<br class="gmail_msg">
llvm/trunk/lib/DebugInfo/DWARF/DWARFDie.cpp<br
class="gmail_msg">
<br class="gmail_msg">
Modified:
llvm/trunk/lib/DebugInfo/DWARF/DWARFDie.cpp<br
class="gmail_msg">
URL: <a moz-do-not-send="true"
href="http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/DebugInfo/DWARF/DWARFDie.cpp?rev=296253&r1=296252&r2=296253&view=diff"
rel="noreferrer" class="gmail_msg" target="_blank">http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/DebugInfo/DWARF/DWARFDie.cpp?rev=296253&r1=296252&r2=296253&view=diff</a><br
class="gmail_msg">
==============================================================================<br
class="gmail_msg">
--- llvm/trunk/lib/DebugInfo/DWARF/DWARFDie.cpp
(original)<br class="gmail_msg">
+++ llvm/trunk/lib/DebugInfo/DWARF/DWARFDie.cpp Sat
Feb 25 07:15:57 2017<br class="gmail_msg">
@@ -329,6 +329,12 @@ void DWARFDie::dump(raw_ostream
&OS, uns<br class="gmail_msg">
<br class="gmail_msg">
// Dump all data in the DIE for the
attributes.<br class="gmail_msg">
for (const auto &AttrSpec :
AbbrevDecl->attributes()) {<br class="gmail_msg">
+ if (AttrSpec.Form ==
DW_FORM_implicit_const) {<br class="gmail_msg">
+ // We are dumping .debug_info section ,<br
class="gmail_msg">
+ // implicit_const attribute values are
not really stored here,<br class="gmail_msg">
+ // but in .debug_abbrev section. So we
just skip such attrs.<br class="gmail_msg">
+ continue;<br class="gmail_msg">
+ }<br class="gmail_msg">
dumpAttribute(OS, *this, &offset,
AttrSpec.Attr, AttrSpec.Form,<br class="gmail_msg">
Indent);<br
class="gmail_msg">
}<br class="gmail_msg">
<br class="gmail_msg">
<br class="gmail_msg">
_______________________________________________<br
class="gmail_msg">
llvm-commits mailing list<br class="gmail_msg">
<a moz-do-not-send="true"
href="mailto:llvm-commits@lists.llvm.org"
class="gmail_msg" target="_blank">llvm-commits@lists.llvm.org</a><br
class="gmail_msg">
<a moz-do-not-send="true"
href="http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits"
rel="noreferrer" class="gmail_msg" target="_blank">http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits</a><br
class="gmail_msg">
</blockquote>
</div>
</blockquote>
<br class="gmail_msg">
</div>
<div bgcolor="#FFFFFF" text="#000000" class="gmail_msg">
<pre class="m_-7636712434836838175moz-signature gmail_msg" cols="72">--
Best Regards,
Victor</pre>
</div>
</blockquote>
</div>
</div>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
Best Regards,
Victor</pre>
</body>
</html>