powerpc/math-emu: Fix load/store indexed emulation

Load/store indexed instructions where the index register RA=R0, such
as "lfdx f1,0,r3", are not illegal.

Load/store indexed with update instructions where the index register
RA=R0, such as "lfdux f1,0,r3", are invalid, and, to be consistent
with existing math-emu behavior for other invalid instruction forms,
will signal as illegal.

Signed-off-by: James Yang <James.Yang@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
James Yang 2013-07-04 16:18:44 -05:00 committed by Benjamin Herrenschmidt
parent 5f20be4478
commit cc7059b5ea

View File

@ -380,21 +380,16 @@ do_mathemu(struct pt_regs *regs)
case XE:
idx = (insn >> 16) & 0x1f;
op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
if (!idx) {
if (((insn >> 1) & 0x3ff) == STFIWX)
op1 = (void *)(regs->gpr[(insn >> 11) & 0x1f]);
else
goto illegal;
} else {
op1 = (void *)(regs->gpr[idx] + regs->gpr[(insn >> 11) & 0x1f]);
}
op1 = (void *)((idx ? regs->gpr[idx] : 0)
+ regs->gpr[(insn >> 11) & 0x1f]);
break;
case XEU:
idx = (insn >> 16) & 0x1f;
if (!idx)
goto illegal;
op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
op1 = (void *)((idx ? regs->gpr[idx] : 0)
op1 = (void *)(regs->gpr[idx]
+ regs->gpr[(insn >> 11) & 0x1f]);
break;