On Tue, Jul 10, 2007 at 06:34:54PM +0100, Thiemo Seufer wrote: > > -#if (_THREAD_SIZE - 32) < 0x10000 > > +#if (_THREAD_SIZE) < 0x10000 > > PTR_ADDIU t0, $28, _THREAD_SIZE - 32 > > #else > > PTR_LI t0, _THREAD_SIZE - 32 > > This doesn't look right. I think it should be > > #if (_THREAD_SIZE - 32) < 0x8000 > > in order to avoid an overflow of the immediate. Indeed - that's the limitation of the (d)addiu instruction. But (d)addu instead handle large constants just fine, so I'd below patch instead. So why not let the assembler do the dirty work. Ralf Signed-off-by: Ralf Baechle <ralf@xxxxxxxxxxxxxx> diff --git a/arch/mips/kernel/r4k_switch.S b/arch/mips/kernel/r4k_switch.S index 65f0f91..d9bfae5 100644 --- a/arch/mips/kernel/r4k_switch.S +++ b/arch/mips/kernel/r4k_switch.S @@ -85,12 +85,7 @@ move $28, a2 cpu_restore_nonscratch a1 -#if (_THREAD_SIZE) < 0x10000 - PTR_ADDIU t0, $28, _THREAD_SIZE - 32 -#else - PTR_LI t0, _THREAD_SIZE - 32 - PTR_ADDU t0, $28 -#endif + PTR_ADDU t0, $28, _THREAD_SIZE - 32 set_saved_sp t0, t1, t2 #ifdef CONFIG_MIPS_MT_SMTC /* Read-modify-writes of Status must be atomic on a VPE */
