| Message ID | 20170621024831.26019-11-rth@twiddle.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Richard Henderson <rth@twiddle.net> writes: > Copy s->nb_globals or s->nb_temps to a local variable for the purposes > of iteration. This should allow the compiler to use low-overhead > looping constructs on some hosts. > > Signed-off-by: Richard Henderson <rth@twiddle.net> > --- > tcg/tcg.c | 27 ++++++++++----------------- > 1 file changed, 10 insertions(+), 17 deletions(-) > > diff --git a/tcg/tcg.c b/tcg/tcg.c > index e78140b..c228f1e 100644 > --- a/tcg/tcg.c > +++ b/tcg/tcg.c > @@ -943,23 +943,16 @@ void tcg_gen_callN(TCGContext *s, void *func, TCGArg ret, > > static void tcg_reg_alloc_start(TCGContext *s) > { > - int i; > + int i, n; > TCGTemp *ts; > - for(i = 0; i < s->nb_globals; i++) { > + > + for (i = 0, n = s->nb_globals; i < n; i++) { > ts = &s->temps[i]; > - if (ts->fixed_reg) { > - ts->val_type = TEMP_VAL_REG; > - } else { > - ts->val_type = TEMP_VAL_MEM; > - } > + ts->val_type = (ts->fixed_reg ? TEMP_VAL_REG : TEMP_VAL_MEM); > } > - for(i = s->nb_globals; i < s->nb_temps; i++) { > + for (n = s->nb_temps; i < n; i++) { A one line comment like /* i continues on from s->nb_globals above */ might prevent a momentary confusion when reading through. > ts = &s->temps[i]; > - if (ts->temp_local) { > - ts->val_type = TEMP_VAL_MEM; > - } else { > - ts->val_type = TEMP_VAL_DEAD; > - } > + ts->val_type = (ts->temp_local ? TEMP_VAL_MEM : TEMP_VAL_DEAD); > ts->mem_allocated = 0; > ts->fixed_reg = 0; > } > @@ -2050,9 +2043,9 @@ static void temp_save(TCGContext *s, TCGTemp *ts, TCGRegSet allocated_regs) > temporary registers needs to be allocated to store a constant. */ > static void save_globals(TCGContext *s, TCGRegSet allocated_regs) > { > - int i; > + int i, n; > > - for (i = 0; i < s->nb_globals; i++) { > + for (i = 0, n = s->nb_globals; i < n; i++) { > temp_save(s, &s->temps[i], allocated_regs); > } > } > @@ -2062,9 +2055,9 @@ static void save_globals(TCGContext *s, TCGRegSet allocated_regs) > temporary registers needs to be allocated to store a constant. */ > static void sync_globals(TCGContext *s, TCGRegSet allocated_regs) > { > - int i; > + int i, n; > > - for (i = 0; i < s->nb_globals; i++) { > + for (i = 0, n = s->nb_globals; i < n; i++) { > TCGTemp *ts = &s->temps[i]; > tcg_debug_assert(ts->val_type != TEMP_VAL_REG > || ts->fixed_reg Otherwise: Reviewed-by: Alex Bennée <alex.bennee@linaro.org> -- Alex Bennée
diff --git a/tcg/tcg.c b/tcg/tcg.c index e78140b..c228f1e 100644 --- a/tcg/tcg.c +++ b/tcg/tcg.c @@ -943,23 +943,16 @@ void tcg_gen_callN(TCGContext *s, void *func, TCGArg ret, static void tcg_reg_alloc_start(TCGContext *s) { - int i; + int i, n; TCGTemp *ts; - for(i = 0; i < s->nb_globals; i++) { + + for (i = 0, n = s->nb_globals; i < n; i++) { ts = &s->temps[i]; - if (ts->fixed_reg) { - ts->val_type = TEMP_VAL_REG; - } else { - ts->val_type = TEMP_VAL_MEM; - } + ts->val_type = (ts->fixed_reg ? TEMP_VAL_REG : TEMP_VAL_MEM); } - for(i = s->nb_globals; i < s->nb_temps; i++) { + for (n = s->nb_temps; i < n; i++) { ts = &s->temps[i]; - if (ts->temp_local) { - ts->val_type = TEMP_VAL_MEM; - } else { - ts->val_type = TEMP_VAL_DEAD; - } + ts->val_type = (ts->temp_local ? TEMP_VAL_MEM : TEMP_VAL_DEAD); ts->mem_allocated = 0; ts->fixed_reg = 0; } @@ -2050,9 +2043,9 @@ static void temp_save(TCGContext *s, TCGTemp *ts, TCGRegSet allocated_regs) temporary registers needs to be allocated to store a constant. */ static void save_globals(TCGContext *s, TCGRegSet allocated_regs) { - int i; + int i, n; - for (i = 0; i < s->nb_globals; i++) { + for (i = 0, n = s->nb_globals; i < n; i++) { temp_save(s, &s->temps[i], allocated_regs); } } @@ -2062,9 +2055,9 @@ static void save_globals(TCGContext *s, TCGRegSet allocated_regs) temporary registers needs to be allocated to store a constant. */ static void sync_globals(TCGContext *s, TCGRegSet allocated_regs) { - int i; + int i, n; - for (i = 0; i < s->nb_globals; i++) { + for (i = 0, n = s->nb_globals; i < n; i++) { TCGTemp *ts = &s->temps[i]; tcg_debug_assert(ts->val_type != TEMP_VAL_REG || ts->fixed_reg
Copy s->nb_globals or s->nb_temps to a local variable for the purposes of iteration. This should allow the compiler to use low-overhead looping constructs on some hosts. Signed-off-by: Richard Henderson <rth@twiddle.net> --- tcg/tcg.c | 27 ++++++++++----------------- 1 file changed, 10 insertions(+), 17 deletions(-)