powerpc/lib/sstep: Add bpermd instruction emulation

This adds emulation for the bpermd instruction.
Tested for correctness against the bpermd instruction on ppc64le.

Signed-off-by: Matt Brown <matthew.brown.dev@gmail.com>
Reviewed-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Matt Brown 2017-07-31 10:58:24 +10:00 committed by Michael Ellerman
parent dcbd19b48d
commit f312793dda

View file

@ -640,6 +640,24 @@ static nokprobe_inline void do_popcnt(struct pt_regs *regs, unsigned long v1,
regs->gpr[ra] = out; /* popcntd */
}
#ifdef CONFIG_PPC64
static nokprobe_inline void do_bpermd(struct pt_regs *regs, unsigned long v1,
unsigned long v2, int ra)
{
unsigned char perm, idx;
unsigned int i;
perm = 0;
for (i = 0; i < 8; i++) {
idx = (v1 >> (i * 8)) & 0xff;
if (idx < 64)
if (v2 & PPC_BIT(idx))
perm |= 1 << i;
}
regs->gpr[ra] = perm;
}
#endif /* CONFIG_PPC64 */
static nokprobe_inline int trap_compare(long v1, long v2)
{
int ret = 0;
@ -1244,7 +1262,11 @@ int analyse_instr(struct instruction_op *op, struct pt_regs *regs,
case 124: /* nor */
regs->gpr[ra] = ~(regs->gpr[rd] | regs->gpr[rb]);
goto logical_done;
#ifdef CONFIG_PPC64
case 252: /* bpermd */
do_bpermd(regs, regs->gpr[rd], regs->gpr[rb], ra);
goto logical_done;
#endif
case 284: /* xor */
regs->gpr[ra] = ~(regs->gpr[rd] ^ regs->gpr[rb]);
goto logical_done;