| Message ID | 20240503072014.24751-7-philmd@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | target/alpha: Implement CF_PCREL | expand |
On 5/3/24 00:20, Philippe Mathieu-Daudé wrote: > Richard Henderson explained on IRC: > > bcond_internal() used to insist that both branch > destination and branch fallthrough are use_goto_tb; > if not, we'd use movcond to compute an indirect jump. > But it's perfectly fine for e.g. the branch fallthrough > to use_goto_tb, and the branch destination to use > an indirect branch. > > Signed-off-by: Richard Henderson <richard.henderson@linaro.org> > Message-Id: <20240424234436.995410-4-richard.henderson@linaro.org> > [PMD: Split bigger patch, part 4/5] > Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> > --- > target/alpha/translate.c | 17 +++++++---------- > 1 file changed, 7 insertions(+), 10 deletions(-) > > diff --git a/target/alpha/translate.c b/target/alpha/translate.c > index 41151f002e..079bd5d3fd 100644 > --- a/target/alpha/translate.c > +++ b/target/alpha/translate.c > @@ -461,23 +461,20 @@ static DisasJumpType gen_bcond_internal(DisasContext *ctx, TCGCond cond, > uint64_t dest = ctx->base.pc_next + disp; > TCGLabel *lab_true = gen_new_label(); > > - if (use_goto_tb(ctx, dest)) { > - tcg_gen_brcondi_i64(cond, cmp, imm, lab_true); > - > + tcg_gen_brcondi_i64(cond, cmp, imm, lab_true); > + if (use_goto_tb(ctx, ctx->base.pc_next)) { > tcg_gen_goto_tb(0); > tcg_gen_movi_i64(cpu_pc, ctx->base.pc_next); > tcg_gen_exit_tb(ctx->base.tb, 0); > - > - gen_set_label(lab_true); > + } > + /* FALLTHRU */ fall through does not work. > + gen_set_label(lab_true); > + if (use_goto_tb(ctx, dest)) { > tcg_gen_goto_tb(1); > tcg_gen_movi_i64(cpu_pc, dest); > tcg_gen_exit_tb(ctx->base.tb, 1); > } else { > - TCGv_i64 i = tcg_constant_i64(imm); > - TCGv_i64 d = tcg_constant_i64(dest); > - TCGv_i64 p = tcg_constant_i64(ctx->base.pc_next); > - > - tcg_gen_movcond_i64(cond, cpu_pc, cmp, i, d, p); > + tcg_gen_movi_i64(cpu_pc, dest); > tcg_gen_lookup_and_goto_ptr(); > } Need the whole else replicated above. r~
diff --git a/target/alpha/translate.c b/target/alpha/translate.c index 41151f002e..079bd5d3fd 100644 --- a/target/alpha/translate.c +++ b/target/alpha/translate.c @@ -461,23 +461,20 @@ static DisasJumpType gen_bcond_internal(DisasContext *ctx, TCGCond cond, uint64_t dest = ctx->base.pc_next + disp; TCGLabel *lab_true = gen_new_label(); - if (use_goto_tb(ctx, dest)) { - tcg_gen_brcondi_i64(cond, cmp, imm, lab_true); - + tcg_gen_brcondi_i64(cond, cmp, imm, lab_true); + if (use_goto_tb(ctx, ctx->base.pc_next)) { tcg_gen_goto_tb(0); tcg_gen_movi_i64(cpu_pc, ctx->base.pc_next); tcg_gen_exit_tb(ctx->base.tb, 0); - - gen_set_label(lab_true); + } + /* FALLTHRU */ + gen_set_label(lab_true); + if (use_goto_tb(ctx, dest)) { tcg_gen_goto_tb(1); tcg_gen_movi_i64(cpu_pc, dest); tcg_gen_exit_tb(ctx->base.tb, 1); } else { - TCGv_i64 i = tcg_constant_i64(imm); - TCGv_i64 d = tcg_constant_i64(dest); - TCGv_i64 p = tcg_constant_i64(ctx->base.pc_next); - - tcg_gen_movcond_i64(cond, cpu_pc, cmp, i, d, p); + tcg_gen_movi_i64(cpu_pc, dest); tcg_gen_lookup_and_goto_ptr(); }