<html>
<head>
<base href="https://llvm.org/bugs/" />
</head>
<body><table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW --- - WinEHPrepare fails on __try / __finally inside __try / __except"
href="https://llvm.org/bugs/show_bug.cgi?id=24773">24773</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>WinEHPrepare fails on __try / __finally inside __try / __except
</td>
</tr>
<tr>
<th>Product</th>
<td>libraries
</td>
</tr>
<tr>
<th>Version</th>
<td>trunk
</td>
</tr>
<tr>
<th>Hardware</th>
<td>PC
</td>
</tr>
<tr>
<th>OS</th>
<td>Windows NT
</td>
</tr>
<tr>
<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>normal
</td>
</tr>
<tr>
<th>Priority</th>
<td>P
</td>
</tr>
<tr>
<th>Component</th>
<td>Common Code Generator Code
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>rnk@google.com
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
</tr>
<tr>
<th>Classification</th>
<td>Unclassified
</td>
</tr></table>
<p>
<div>
<pre>Created <span class=""><a href="attachment.cgi?id=14864" name="attach_14864" title="IR">attachment 14864</a> <a href="attachment.cgi?id=14864&action=edit" title="IR">[details]</a></span>
IR
Two things go wrong starting from this C++ test case (IR attached):
extern "C" int printf(const char *, ...);
int do_div(int a, int b) { return a / b; }
int main() {
int r = 0;
__try {
__try {
r = do_div(1, 0);
} __finally {
printf("finally\n");
}
} __except (1) {
printf("caught\n");
}
printf("1 / 0: %d\n", r);
return 0;
}
First, having a single-BB catch funclet seems to confuse WinEHPrepare. It ends
up cloning the subsequent blocks and transforms the "implausible" ret as
unreachable.
Second, if I run -O1 on the IR, demotion fails like this:
$ opt -O1 -winehprepare t.ll -S -o -
Instruction does not dominate all uses!
%call.wineh.reload.wineh.reload = load i32, i32*
%call.wineh.reload.wineh.spillslot
%call4 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([11 x i8],
[11 x i8]* @"\01??_C@_0L@HIGBIMNM@1?5?1?50?3?5?$CFd?6?$AA@", i32 0, i32 0), i32
%call.wineh.reload.wineh.reload)
LLVM ERROR: Broken function found, compilation aborted!</pre>
</div>
</p>
<hr>
<span>You are receiving this mail because:</span>
<ul>
<li>You are on the CC list for the bug.</li>
</ul>
</body>
</html>