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/* https://bugs.kde.org/show_bug.cgi?id=308627 */
#include "../../memcheck.h"
#include <stdio.h>
typedef unsigned long ULong;
typedef struct {
ULong w64[2]; /* Note: little-endian */
} V128;
static int getMSBs16x8(V128 v)
{
int result;
__asm__("movups %1,%%xmm6\n"
"\tpmovmskb %%xmm6,%0\n"
: "=r" (result) : "m" (v) : "xmm6");
return result;
}
/* Set the V bits on the data at "addr". Note the convention: A zero
bit means "defined"; 1 means "undefined". */
static void set_vbits(V128 *addr, V128 vbits)
{
int i;
for (i=0 ; i<2 ; ++i) {
(void)VALGRIND_SET_VBITS(&addr->w64[i], &vbits.w64[i], sizeof(vbits.w64[i]));
}
}
static void print(V128 vbits, V128 val, int bit, int result)
{
printf("vbits=0x%016lx%016lx val=0x%016lx%016lx bit=%d result=%d\n",
vbits.w64[1], vbits.w64[0], val.w64[1], val.w64[0],
bit, result);
}
/* Use a value that we know is invalid. */
static void use(int index, int invalid)
{
/* Convince GCC it does not know what is in "invalid" so it cannot
possibly optimize away the conditional branch below. */
__asm__ ("" : "=r" (invalid) : "0" (invalid));
/* Create a conditional branch on which our output depends, so that
memcheck cannot possibly optimize it away, either. */
fprintf(stderr, "%d: Invalid value is %s\n",
index, invalid ? "true" : "false");
}
static void doit(ULong vbits_hi, ULong vbits_lo, ULong val_hi, ULong val_lo)
{
V128 vbits = { { vbits_lo, vbits_hi } };
V128 val = { { val_lo, val_hi } };
/* Since we are about to mark "val" partially undefined, make a
copy that we can use without generating a memcheck warning. */
V128 val_copy = val;
set_vbits(&val, vbits);
int result = getMSBs16x8(val);
int vbits_mask = getMSBs16x8(vbits);
int bit = 0; ULong mask = (1UL << bit);
if ((vbits_mask & mask) == 0) print(vbits, val_copy, bit, result & mask);
else use(bit, result & mask);
bit = 1; mask = (1UL << bit);
if ((vbits_mask & mask) == 0) print(vbits, val_copy, bit, result & mask);
else use(bit, result & mask);
bit = 2; mask = (1UL << bit);
if ((vbits_mask & mask) == 0) print(vbits, val_copy, bit, result & mask);
else use(bit, result & mask);
bit = 3; mask = (1UL << bit);
if ((vbits_mask & mask) == 0) print(vbits, val_copy, bit, result & mask);
else use(bit, result & mask);
bit = 4; mask = (1UL << bit);
if ((vbits_mask & mask) == 0) print(vbits, val_copy, bit, result & mask);
else use(bit, result & mask);
bit = 5; mask = (1UL << bit);
if ((vbits_mask & mask) == 0) print(vbits, val_copy, bit, result & mask);
else use(bit, result & mask);
bit = 6 ; mask = (1UL << bit);
if ((vbits_mask & mask) == 0) print(vbits, val_copy, bit, result & mask);
else use(bit, result & mask);
bit = 7 ; mask = (1UL << bit);
if ((vbits_mask & mask) == 0) print(vbits, val_copy, bit, result & mask);
else use(bit, result & mask);
bit = 8 ; mask = (1UL << bit);
if ((vbits_mask & mask) == 0) print(vbits, val_copy, bit, result & mask);
else use(bit, result & mask);
bit = 9 ; mask = (1UL << bit);
if ((vbits_mask & mask) == 0) print(vbits, val_copy, bit, result & mask);
else use(bit, result & mask);
bit = 10 ; mask = (1UL << bit);
if ((vbits_mask & mask) == 0) print(vbits, val_copy, bit, result & mask);
else use(bit, result & mask);
bit = 11 ; mask = (1UL << bit);
if ((vbits_mask & mask) == 0) print(vbits, val_copy, bit, result & mask);
else use(bit, result & mask);
bit = 12 ; mask = (1UL << bit);
if ((vbits_mask & mask) == 0) print(vbits, val_copy, bit, result & mask);
else use(bit, result & mask);
bit = 13 ; mask = (1UL << bit);
if ((vbits_mask & mask) == 0) print(vbits, val_copy, bit, result & mask);
else use(bit, result & mask);
bit = 14 ; mask = (1UL << bit);
if ((vbits_mask & mask) == 0) print(vbits, val_copy, bit, result & mask);
else use(bit, result & mask);
bit = 15 ; mask = (1UL << bit);
if ((vbits_mask & mask) == 0) print(vbits, val_copy, bit, result & mask);
else use(bit, result & mask);
}
int main(int argc, char *argv[])
{
doit(0x0000000000000000, 0x0000000000000000,
0x0000000000000000, 0x0000000000000000);
doit(0x0707070707070707, 0x0707070707070707,
0x0000000000000000, 0x0000000000000000);
doit(0x8080808080808080, 0x8080808080808080,
0x0000000000000000, 0x0000000000000000);
doit(0x13579BDF02468ACE, 0xFEDCBA9876543210,
0xFEEDFACEDEADBEEF, 0xFEE1DEADDABBAD00);
return 0;
}
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