Re: [PATCH 3/5] powerpc/lib/sstep: Add bpermd instruction emulation
From: Segher Boessenkool <hidden>
Date: 2017-07-13 07:28:27
On Thu, Jul 13, 2017 at 01:25:46PM +1000, Matt Brown wrote:
+static nokprobe_inline void do_bpermd(struct pt_regs *regs, unsigned long v1,
+ unsigned long v2, int ra)
+{
+ unsigned int idx, i;
+ unsigned char perm;
+
+ perm = 0x0;
+ for (i = 0; i < 8; i++) {
+ idx = (v1 >> (i * 8)) & 0xff;
+ if (idx < 64)
+ perm |= (v2 & (1 << idx)) >> (idx - i);
That doesn't work I think, the bit numbers ("idx") are big-endian?
+ } + regs->gpr[ra] = 0 | perm;
And that is just silly :-)
+}
Segher