target/loongarch: Remove cpu_fcsr0

All of the fpu operations are defined with TCG_CALL_NO_WG, but they
all modify FCSR0.  The most efficient way to fix this is to remove
cpu_fcsr0, and instead use explicit load and store operations for the
two instructions that manipulate that value.

Acked-by: Qi Hu <huqi@loongson.cn>
Reviewed-by: Song Gao <gaosong@loongson.cn>
Reported-by: Feiyang Chen <chenfeiyang@loongson.cn>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2022-08-06 10:04:44 -07:00
parent 7b06148df8
commit 10dcb08b03
6 changed files with 36 additions and 22 deletions

View file

@ -60,38 +60,39 @@ static bool trans_movgr2fcsr(DisasContext *ctx, arg_movgr2fcsr *a)
TCGv Rj = gpr_src(ctx, a->rj, EXT_NONE);
if (mask == UINT32_MAX) {
tcg_gen_extrl_i64_i32(cpu_fcsr0, Rj);
tcg_gen_st32_i64(Rj, cpu_env, offsetof(CPULoongArchState, fcsr0));
} else {
TCGv_i32 fcsr0 = tcg_temp_new_i32();
TCGv_i32 temp = tcg_temp_new_i32();
tcg_gen_ld_i32(fcsr0, cpu_env, offsetof(CPULoongArchState, fcsr0));
tcg_gen_extrl_i64_i32(temp, Rj);
tcg_gen_andi_i32(temp, temp, mask);
tcg_gen_andi_i32(cpu_fcsr0, cpu_fcsr0, ~mask);
tcg_gen_or_i32(cpu_fcsr0, cpu_fcsr0, temp);
tcg_gen_andi_i32(fcsr0, fcsr0, ~mask);
tcg_gen_or_i32(fcsr0, fcsr0, temp);
tcg_gen_st_i32(fcsr0, cpu_env, offsetof(CPULoongArchState, fcsr0));
tcg_temp_free_i32(temp);
/*
* Install the new rounding mode to fpu_status, if changed.
* Note that FCSR3 is exactly the rounding mode field.
*/
if (mask != FCSR0_M3) {
return true;
}
tcg_temp_free_i32(fcsr0);
}
gen_helper_set_rounding_mode(cpu_env, cpu_fcsr0);
/*
* Install the new rounding mode to fpu_status, if changed.
* Note that FCSR3 is exactly the rounding mode field.
*/
if (mask & FCSR0_M3) {
gen_helper_set_rounding_mode(cpu_env);
}
return true;
}
static bool trans_movfcsr2gr(DisasContext *ctx, arg_movfcsr2gr *a)
{
TCGv_i32 temp = tcg_temp_new_i32();
TCGv dest = gpr_dst(ctx, a->rd, EXT_NONE);
tcg_gen_andi_i32(temp, cpu_fcsr0, fcsr_mask[a->fcsrs]);
tcg_gen_ext_i32_i64(dest, temp);
tcg_gen_ld32u_i64(dest, cpu_env, offsetof(CPULoongArchState, fcsr0));
tcg_gen_andi_i64(dest, dest, fcsr_mask[a->fcsrs]);
gen_set_gpr(a->rd, dest, EXT_NONE);
tcg_temp_free_i32(temp);
return true;
}