target/alpha: Split out gen_pc_disp

Prepare for pcrel by not modifying cpu_pc before use,
in the case of JSR.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20240503072014.24751-9-philmd@linaro.org>
This commit is contained in:
Richard Henderson 2024-05-03 09:20:12 +02:00
parent 82b60d2509
commit b1a3eacf31

View file

@ -252,6 +252,11 @@ static void st_flag_byte(TCGv val, unsigned shift)
tcg_gen_st8_i64(val, tcg_env, get_flag_ofs(shift));
}
static void gen_pc_disp(DisasContext *ctx, TCGv dest, int32_t disp)
{
tcg_gen_movi_i64(dest, ctx->base.pc_next + disp);
}
static void gen_excp_1(int exception, int error_code)
{
TCGv_i32 tmp1, tmp2;
@ -263,7 +268,7 @@ static void gen_excp_1(int exception, int error_code)
static DisasJumpType gen_excp(DisasContext *ctx, int exception, int error_code)
{
tcg_gen_movi_i64(cpu_pc, ctx->base.pc_next);
gen_pc_disp(ctx, cpu_pc, 0);
gen_excp_1(exception, error_code);
return DISAS_NORETURN;
}
@ -427,14 +432,12 @@ static DisasJumpType gen_store_conditional(DisasContext *ctx, int ra, int rb,
static void gen_goto_tb(DisasContext *ctx, int idx, int32_t disp)
{
uint64_t dest = ctx->base.pc_next + disp;
if (translator_use_goto_tb(&ctx->base, dest)) {
if (translator_use_goto_tb(&ctx->base, ctx->base.pc_next + disp)) {
tcg_gen_goto_tb(idx);
tcg_gen_movi_i64(cpu_pc, dest);
gen_pc_disp(ctx, cpu_pc, disp);
tcg_gen_exit_tb(ctx->base.tb, idx);
} else {
tcg_gen_movi_i64(cpu_pc, dest);
gen_pc_disp(ctx, cpu_pc, disp);
tcg_gen_lookup_and_goto_ptr();
}
}
@ -442,7 +445,7 @@ static void gen_goto_tb(DisasContext *ctx, int idx, int32_t disp)
static DisasJumpType gen_bdirect(DisasContext *ctx, int ra, int32_t disp)
{
if (ra != 31) {
tcg_gen_movi_i64(ctx->ir[ra], ctx->base.pc_next);
gen_pc_disp(ctx, ctx->ir[ra], 0);
}
/* Notice branch-to-next; used to initialize RA with the PC. */
@ -1091,7 +1094,7 @@ static DisasJumpType gen_call_pal(DisasContext *ctx, int palcode)
}
/* Allow interrupts to be recognized right away. */
tcg_gen_movi_i64(cpu_pc, ctx->base.pc_next);
gen_pc_disp(ctx, cpu_pc, 0);
return DISAS_PC_UPDATED_NOCHAIN;
case 0x36:
@ -1138,19 +1141,17 @@ static DisasJumpType gen_call_pal(DisasContext *ctx, int palcode)
#else
{
TCGv tmp = tcg_temp_new();
uint64_t exc_addr = ctx->base.pc_next;
uint64_t entry = ctx->palbr;
uint64_t entry;
gen_pc_disp(ctx, tmp, 0);
if (ctx->tbflags & ENV_FLAG_PAL_MODE) {
exc_addr |= 1;
tcg_gen_ori_i64(tmp, tmp, 1);
} else {
tcg_gen_movi_i64(tmp, 1);
st_flag_byte(tmp, ENV_FLAG_PAL_SHIFT);
st_flag_byte(tcg_constant_i64(1), ENV_FLAG_PAL_SHIFT);
}
tcg_gen_movi_i64(tmp, exc_addr);
tcg_gen_st_i64(tmp, tcg_env, offsetof(CPUAlphaState, exc_addr));
entry = ctx->palbr;
entry += (palcode & 0x80
? 0x2000 + (palcode - 0x80) * 64
: 0x1000 + palcode * 64);
@ -2344,9 +2345,13 @@ static DisasJumpType translate_one(DisasContext *ctx, uint32_t insn)
/* JMP, JSR, RET, JSR_COROUTINE. These only differ by the branch
prediction stack action, which of course we don't implement. */
vb = load_gpr(ctx, rb);
tcg_gen_andi_i64(cpu_pc, vb, ~3);
if (ra != 31) {
tcg_gen_movi_i64(ctx->ir[ra], ctx->base.pc_next);
tmp = tcg_temp_new();
tcg_gen_andi_i64(tmp, vb, ~3);
gen_pc_disp(ctx, ctx->ir[ra], 0);
tcg_gen_mov_i64(cpu_pc, tmp);
} else {
tcg_gen_andi_i64(cpu_pc, vb, ~3);
}
ret = DISAS_PC_UPDATED;
break;
@ -2908,7 +2913,7 @@ static void alpha_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
gen_goto_tb(ctx, 0, 0);
break;
case DISAS_PC_STALE:
tcg_gen_movi_i64(cpu_pc, ctx->base.pc_next);
gen_pc_disp(ctx, cpu_pc, 0);
/* FALLTHRU */
case DISAS_PC_UPDATED:
tcg_gen_lookup_and_goto_ptr();