Commit 57fca134 authored by Tom Musta's avatar Tom Musta Committed by Alexander Graf
Browse files

target-ppc: Optimize rlwnm MB=0 ME=31 



Optimize the special case of rlwnm where MB=0 and ME=31.  This can
be implemented using a ROTL.

Suggested-by: default avatarRichard Henderson <rth@twiddle.net>
Signed-off-by: default avatarTom Musta <tommusta@gmail.com>
Reviewed-by: default avatarRichard Henderson <rth@twiddle.net>
Signed-off-by: default avatarAlexander Graf <agraf@suse.de>
parent 8979c2f6

target-ppc/translate.c

+34 −22
Original line number Diff line number Diff line
@@ -1721,13 +1721,26 @@ static void gen_rlwinm(DisasContext *ctx) 
static void gen_rlwnm(DisasContext *ctx)

{

    uint32_t mb, me;

    mb = MB(ctx->opcode);

    me = ME(ctx->opcode);



    if (likely(mb == 0 && me == 31)) {

        TCGv_i32 t0, t1;

        t0 = tcg_temp_new_i32();

        t1 = tcg_temp_new_i32();

        tcg_gen_trunc_tl_i32(t0, cpu_gpr[rB(ctx->opcode)]);

        tcg_gen_trunc_tl_i32(t1, cpu_gpr[rS(ctx->opcode)]);

        tcg_gen_andi_i32(t0, t0, 0x1f);

        tcg_gen_rotl_i32(t1, t1, t0);

        tcg_gen_extu_i32_tl(cpu_gpr[rA(ctx->opcode)], t1);

        tcg_temp_free_i32(t0);

        tcg_temp_free_i32(t1);

    } else {

        TCGv t0;

#if defined(TARGET_PPC64)

        TCGv t1;

#endif



    mb = MB(ctx->opcode);

    me = ME(ctx->opcode);

        t0 = tcg_temp_new();

        tcg_gen_andi_tl(t0, cpu_gpr[rB(ctx->opcode)], 0x1f);

#if defined(TARGET_PPC64)
@@ -1746,12 +1759,11 @@ static void gen_rlwnm(DisasContext *ctx) 
#endif

            tcg_gen_andi_tl(cpu_gpr[rA(ctx->opcode)], t0, MASK(mb, me));

        } else {

#if defined(TARGET_PPC64)

            tcg_gen_andi_tl(t0, t0, MASK(32, 63));

#endif

            tcg_gen_mov_tl(cpu_gpr[rA(ctx->opcode)], t0);

        }

        tcg_temp_free(t0);

    }

    if (unlikely(Rc(ctx->opcode) != 0))

        gen_set_Rc0(ctx, cpu_gpr[rA(ctx->opcode)]);

}