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<base href="https://bugs.llvm.org/">
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<body><table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - wrong code with "opt -structurizecfg -simplifycfg -instcombine -jump-threading -structurizecfg -sroa -jump-threading -constprop""
href="https://bugs.llvm.org/show_bug.cgi?id=41698">41698</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>wrong code with "opt -structurizecfg -simplifycfg -instcombine -jump-threading -structurizecfg -sroa -jump-threading -constprop"
</td>
</tr>
<tr>
<th>Product</th>
<td>libraries
</td>
</tr>
<tr>
<th>Version</th>
<td>8.0
</td>
</tr>
<tr>
<th>Hardware</th>
<td>PC
</td>
</tr>
<tr>
<th>OS</th>
<td>Linux
</td>
</tr>
<tr>
<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>enhancement
</td>
</tr>
<tr>
<th>Priority</th>
<td>P
</td>
</tr>
<tr>
<th>Component</th>
<td>Scalar Optimizations
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>cszide@163.com
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
</tr></table>
<p>
<div>
<pre>Created <span class=""><a href="attachment.cgi?id=21863" name="attach_21863" title=".bc file of the source code">attachment 21863</a> <a href="attachment.cgi?id=21863&action=edit" title=".bc file of the source code">[details]</a></span>
.bc file of the source code
$clang -v
clang version 8.0.0 (tags/RELEASE_800/final)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir:
/home/jack-zhou/clang+llvm-8.0.0-x86_64-linux-gnu-ubuntu-18.04/bin
Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/8
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/5
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/5.5.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/6
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/6.5.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7.4.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/8
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7.4.0
Candidate multilib: .;@m64
Candidate multilib: 32;@m32
Candidate multilib: x32;@mx32
Selected multilib: .;@m64
$clang -O3 -c -emit-llvm -mllvm -disable-llvm-optzns small.c -o small.bc
$clang small.bc -o small1.out && ./small1.out
0
0
$opt -structurizecfg -simplifycfg -instcombine -jump-threading -structurizecfg
-sroa -jump-threading -constprop small.bc -o small-opt.bc
$clang small-opt.bc -o small2.out && ./small2.out
1
0
However, by using lli, the output is correct.
$lli small-opt.bc
0
0
-----------------------------------------------
#include <stdio.h>
typedef signed char int8_t;
typedef short int int16_t;
typedef int int32_t;
typedef long int int64_t;
/* Unsigned. */
typedef unsigned char uint8_t;
typedef unsigned short int uint16_t;
typedef unsigned int uint32_t;
typedef unsigned long int uint64_t;
#define CHAR_BIT 8
#define safe_sub_func_int16_t_s_s(_si1, _si2)
\
({
\
int16_t si1 = (_si1);
\
int16_t si2 = (_si2);
\
(((((int16_t)(si1)) ^ ((int16_t)(si2))) &
\
(((((int16_t)(si1)) ^
\
((((int16_t)(si1)) ^ ((int16_t)(si2))) &
\
(((int16_t)1) << (sizeof(int16_t) * CHAR_BIT - 1)))) -
\
((int16_t)(si2))) ^
\
((int16_t)(si2)))) < ((int16_t)0))
\
? ((int16_t)(si1))
\
: (((int16_t)(si1)) - ((int16_t)(si2)));
\
})
struct a {
int8_t b;
int32_t c;
int32_t d;
uint8_t e;
} f[2], g, t;
struct {
unsigned b;
} k;
struct {
int32_t h;
int16_t j;
} l;
struct {
struct a c;
} m;
int8_t n;
int32_t *o = &f[0].c;
static struct a p = {9};
struct a q() {
int8_t r[5][5][7] = {0};
int32_t **s[10];
int32_t ***x = &s[2];
int i;
for (i = 0; i < 10; i++)
s[i] = &o;
u:
if (r[3][3][6] > f[0].d) {
int32_t v;
for (; m.c.e; safe_sub_func_int16_t_s_s(l.h, 1))
if (k.b)
goto u;
for (l.j = 5; 0;)
;
if (p.b)
goto aa;
} else
return g;
aa:
for (; n < 4; n++)
***x = 1;
return t;
}
void main() {
int i;
q();
for (i = 0; i < 2; i++)
printf("%d\n", f[i].c);
}</pre>
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