https://bugs.llvm.org/show_bug.cgi?id=41542
Bug ID: 41542
Summary: Broken function found with "opt -lowerswitch
-loop-instsimplify -jump-threading
-loop-versioning-licm"
Product: libraries
Version: trunk
Hardware: PC
OS: Linux
Status: NEW
Severity: enhancement
Priority: P
Component: Scalar Optimizations
Assignee: [email protected]
Reporter: [email protected]
CC: [email protected]
Created attachment 21802
--> https://bugs.llvm.org/attachment.cgi?id=21802&action=edit
.bc file of the source code
$clang -v
clang version 9.0.0 (trunk 355281)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /home/jack-zhou/Documents/llvm/llvm_truck/llvm/build4/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/7.3.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/8
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7.3.0
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
$opt -lowerswitch -loop-instsimplify -jump-threading -loop-versioning-licm
small.bc -o small-opt.bc
PHI nodes must have at least one entry. If the block is dead, the PHI should
be removed!
%.lcssa = phi i32
in function f
LLVM ERROR: Broken function found, compilation aborted!
By using godbolt, it shows that llvm 7/trunk version have this problem, but
llvm 6 is fine.
--------------------------------------------------------
struct a {};
struct {
int b;
} c, d;
int e;
int f() {
int g;
for (; 7;)
h:;
{
struct a *i[1];
struct a j;
int k[1];
for (; e;)
for (; g; g++)
i[g] = &c;
k[e] = 6;
if (d.b)
goto h;
for (; 0;)
return 0;
}
}
--
You are receiving this mail because:
You are on the CC list for the bug._______________________________________________
llvm-bugs mailing list
[email protected]
https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-bugs
