On Wed, Oct 05, 2022 at 08:44:19PM -0700, Richard Henderson wrote:
> Allow targets to allocate extended-basic-block temps.
>
> Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
> ---
> include/tcg/tcg-op.h | 2 ++
> include/tcg/tcg.h | 20 +++++++++++++++++++-
> tcg/tcg.c | 16 ++++------------
> 3 files changed, 25 insertions(+), 13 deletions(-)
>
> diff --git a/include/tcg/tcg-op.h b/include/tcg/tcg-op.h
> index 209e168305..0ebbee6e24 100644
> --- a/include/tcg/tcg-op.h
> +++ b/include/tcg/tcg-op.h
> @@ -848,6 +848,7 @@ static inline void tcg_gen_plugin_cb_end(void)
> #define tcg_temp_new() tcg_temp_new_i32()
> #define tcg_global_mem_new tcg_global_mem_new_i32
> #define tcg_temp_local_new() tcg_temp_local_new_i32()
> +#define tcg_temp_ebb_new() tcg_temp_ebb_new_i32()
> #define tcg_temp_free tcg_temp_free_i32
> #define tcg_gen_qemu_ld_tl tcg_gen_qemu_ld_i32
> #define tcg_gen_qemu_st_tl tcg_gen_qemu_st_i32
> @@ -855,6 +856,7 @@ static inline void tcg_gen_plugin_cb_end(void)
> #define tcg_temp_new() tcg_temp_new_i64()
> #define tcg_global_mem_new tcg_global_mem_new_i64
> #define tcg_temp_local_new() tcg_temp_local_new_i64()
> +#define tcg_temp_ebb_new() tcg_temp_ebb_new_i64()
> #define tcg_temp_free tcg_temp_free_i64
> #define tcg_gen_qemu_ld_tl tcg_gen_qemu_ld_i64
> #define tcg_gen_qemu_st_tl tcg_gen_qemu_st_i64
> diff --git a/include/tcg/tcg.h b/include/tcg/tcg.h
> index e01a47ec20..3835711d52 100644
> --- a/include/tcg/tcg.h
> +++ b/include/tcg/tcg.h
> @@ -609,7 +609,7 @@ struct TCGContext {
> #endif
>
> GHashTable *const_table[TCG_TYPE_COUNT];
> - TCGTempSet free_temps[TCG_TYPE_COUNT * 2];
> + TCGTempSet free_temps[TCG_TYPE_COUNT * 3];
> TCGTemp temps[TCG_MAX_TEMPS]; /* globals first, temps after */
>
> QTAILQ_HEAD(, TCGOp) ops, free_ops;
> @@ -890,6 +890,12 @@ static inline TCGv_i32 tcg_temp_local_new_i32(void)
> return temp_tcgv_i32(t);
> }
>
> +static inline TCGv_i32 tcg_temp_ebb_new_i32(void)
> +{
> + TCGTemp *t = tcg_temp_new_internal(TCG_TYPE_I32, TEMP_EBB);
> + return temp_tcgv_i32(t);
> +}
> +
> static inline TCGv_i64 tcg_global_mem_new_i64(TCGv_ptr reg, intptr_t offset,
> const char *name)
> {
> @@ -909,6 +915,12 @@ static inline TCGv_i64 tcg_temp_local_new_i64(void)
> return temp_tcgv_i64(t);
> }
>
> +static inline TCGv_i64 tcg_temp_ebb_new_i64(void)
> +{
> + TCGTemp *t = tcg_temp_new_internal(TCG_TYPE_I64, TEMP_EBB);
> + return temp_tcgv_i64(t);
> +}
> +
> static inline TCGv_ptr tcg_global_mem_new_ptr(TCGv_ptr reg, intptr_t offset,
> const char *name)
> {
> @@ -928,6 +940,12 @@ static inline TCGv_ptr tcg_temp_local_new_ptr(void)
> return temp_tcgv_ptr(t);
> }
>
> +static inline TCGv_ptr tcg_temp_ebb_new_ptr(void)
> +{
> + TCGTemp *t = tcg_temp_new_internal(TCG_TYPE_PTR, TEMP_EBB);
> + return temp_tcgv_ptr(t);
> +}
> +
> #if defined(CONFIG_DEBUG_TCG)
> /* If you call tcg_clear_temp_count() at the start of a section of
> * code which is not supposed to leak any TCG temporaries, then
> diff --git a/tcg/tcg.c b/tcg/tcg.c
> index acdbd5a9a2..7aa6cc3451 100644
> --- a/tcg/tcg.c
> +++ b/tcg/tcg.c
> @@ -948,17 +948,8 @@ TCGTemp *tcg_temp_new_internal(TCGType type, TCGTempKind
> kind)
> TCGTemp *ts;
> int idx, k;
>
> - switch (kind) {
> - case TEMP_NORMAL:
> - k = 0;
> - break;
> - case TEMP_LOCAL:
> - k = TCG_TYPE_COUNT;
> - break;
> - default:
> - g_assert_not_reached();
> - }
> - k += type;
> + assert(kind >= TEMP_NORMAL && kind <= TEMP_LOCAL);
Nit: maybe also add QEMU_BUILD_BUG_ON(TEMP_NORMAL != 0)
and QEMU_BUILD_BUG_ON(TEMP_LOCAL != 2), since we are using this for
0-based array indexing here? Alternatively, subtract TEMP_NORMAL
from kind.
> + k = TCG_TYPE_COUNT * kind + type;
>
> idx = find_first_bit(s->free_temps[k].l, TCG_MAX_TEMPS);
> if (idx < TCG_MAX_TEMPS) {
> @@ -1046,6 +1037,7 @@ void tcg_temp_free_internal(TCGTemp *ts)
> */
> return;
> case TEMP_NORMAL:
> + case TEMP_EBB:
> case TEMP_LOCAL:
> break;
> default:
> @@ -1063,7 +1055,7 @@ void tcg_temp_free_internal(TCGTemp *ts)
> ts->temp_allocated = 0;
>
> idx = temp_idx(ts);
> - k = ts->base_type + (ts->kind == TEMP_NORMAL ? 0 : TCG_TYPE_COUNT);
> + k = ts->base_type + ts->kind * TCG_TYPE_COUNT;
> set_bit(idx, s->free_temps[k].l);
> }
>
> --
> 2.34.1
>
>
Reviewed-by: Ilya Leoshkevich <i...@linux.ibm.com>
While not directly related to this patch, it would be good to update
tcg/README with all the new kinds of temporaries. E.g. the EBB ones are
not mentioned there:
TCG instructions operate on variables which are temporaries, local
temporaries or globals.
