Re: [PATCH v3 3/3] powerpc/64: optimise LOAD_REG_IMMEDIATE_SYM()

From: Segher Boessenkool
Date: Mon Aug 19 2019 - 10:25:28 EST


On Mon, Aug 19, 2019 at 01:58:12PM +0000, Christophe Leroy wrote:
> -#define LOAD_REG_IMMEDIATE_SYM(reg,expr) \
> - lis reg,(expr)@highest; \
> - ori reg,reg,(expr)@higher; \
> - rldicr reg,reg,32,31; \
> - oris reg,reg,(expr)@__AS_ATHIGH; \
> - ori reg,reg,(expr)@l;
> +#define LOAD_REG_IMMEDIATE_SYM(reg, tmp, expr) \
> + lis reg, (expr)@highest; \
> + lis tmp, (expr)@__AS_ATHIGH; \
> + ori reg, reg, (expr)@higher; \
> + ori tmp, reg, (expr)@l; \
> + rldimi reg, tmp, 32, 0

That should be

#define LOAD_REG_IMMEDIATE_SYM(reg, tmp, expr) \
lis tmp, (expr)@highest; \
ori tmp, tmp, (expr)@higher; \
lis reg, (expr)@__AS_ATHIGH; \
ori reg, reg, (expr)@l; \
rldimi reg, tmp, 32, 0

(tmp is the high half, reg is the low half, as inputs to that rldimi).


Segher