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SubjectRe: [bug report] perf jit: add source line info support
Hi Dan,

On Wed, Nov 30, 2016 at 10:48 AM, Dan Carpenter
<dan.carpenter@oracle.com> wrote:
> Hello Stephane Eranian,
>
> The patch 598b7c6919c7: "perf jit: add source line info support" from
> Nov 30, 2015, leads to the following static checker warning:
>
> ./tools/perf/util/genelf_debug.c:211 emit_signed_LEB128()
> warn: potential left shift more than type allows '57'
>
> ./tools/perf/util/genelf_debug.c
> 202 static void emit_signed_LEB128(struct buffer_ext *be, long data)
> 203 {
> 204 int more = 1;
> 205 int negative = data < 0;
> 206 int size = sizeof(long) * CHAR_BIT;
> 207 while (more) {
> 208 ubyte cur = data & 0x7F;
> 209 data >>= 7;
> 210 if (negative)
> 211 data |= - (1 << (size - 7));
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^
> This is a no-op on 64 bit systems. I suspect it's not intentional?
>
I suspect size should be: size = sizeof(int) * CHAR_BIT;
I will test that.

> 212 if ((data == 0 && !(cur & 0x40)) ||
> 213 (data == -1l && (cur & 0x40)))
> 214 more = 0;
> 215 else
> 216 cur |= 0x80;
> 217 buffer_ext_add(be, &cur, 1);
> 218 }
> 219 }
>
> regards,
> dan carpenter

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