Pretty small still, but there are two patches that ought

to get backported to stable, so no point in delaying.

r~

The following changes since commit a5ba0a7e4e150d1350a041f0d0ef9ca6c8d7c307:

Merge tag 'pull-aspeed-20241211' of https://github.com/legoater/qemu into staging (2024-12-11 15:16:47 +0000)

https://gitlab.com/rth7680/qemu.git tags/pull-tcg-20241212

for you to fetch changes up to 7ac87b14a92234b6a89b701b4043ad6cf8bdcccf:

target/sparc: Use memcpy() and remove memcpy32() (2024-12-12 14:28:38 -0600)

tcg: Reset free_temps before tcg_optimize

tcg/riscv: Fix StoreStore barrier generation

include/exec: Introduce fpst alias in helper-head.h.inc

target/sparc: Use memcpy() and remove memcpy32()

Philippe Mathieu-Daudé (1):

target/sparc: Use memcpy() and remove memcpy32()

Richard Henderson (2):

tcg: Reset free_temps before tcg_optimize

include/exec: Introduce fpst alias in helper-head.h.inc

Roman Artemev (1):

tcg/riscv: Fix StoreStore barrier generation

include/tcg/tcg-temp-internal.h | 6 ++++++

accel/tcg/plugin-gen.c | 2 +-

target/sparc/win_helper.c | 26 ++++++++------------------

tcg/tcg.c | 5 ++++-

include/exec/helper-head.h.inc | 3 +++

tcg/riscv/tcg-target.c.inc | 2 +-

6 files changed, 23 insertions(+), 21 deletions(-)

When allocating new temps during tcg_optmize, do not re-use

any EBB temps that were used within the TB. We do not have

any idea what span of the TB in which the temp was live.

Introduce tcg_temp_ebb_reset_freed and use before tcg_optimize,

as well as replacing the equivalent in plugin_gen_inject and

tcg_func_start.

Fixes: fb04ab7ddd8 ("tcg/optimize: Lower TCG_COND_TST{EQ,NE} if unsupported")

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2711

Reported-by: wannacu <wannacu2049@gmail.com>

Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>

include/tcg/tcg-temp-internal.h | 6 ++++++

accel/tcg/plugin-gen.c | 2 +-

tcg/tcg.c | 5 ++++-

3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/include/tcg/tcg-temp-internal.h b/include/tcg/tcg-temp-internal.h

--- a/include/tcg/tcg-temp-internal.h

+++ b/include/tcg/tcg-temp-internal.h

@@ -XXX,XX +XXX,XX @@ TCGv_i64 tcg_temp_ebb_new_i64(void);

TCGv_ptr tcg_temp_ebb_new_ptr(void);

TCGv_i128 tcg_temp_ebb_new_i128(void);

+/* Forget all freed EBB temps, so that new allocations produce new temps. */

+static inline void tcg_temp_ebb_reset_freed(TCGContext *s)

+{

+ memset(s->free_temps, 0, sizeof(s->free_temps));

+}

+

#endif /* TCG_TEMP_FREE_H */

diff --git a/accel/tcg/plugin-gen.c b/accel/tcg/plugin-gen.c

index XXXXXXX..XXXXXXX 100644

--- a/accel/tcg/plugin-gen.c

+++ b/accel/tcg/plugin-gen.c

@@ -XXX,XX +XXX,XX @@ static void plugin_gen_inject(struct qemu_plugin_tb *plugin_tb)

* that might be live within the existing opcode stream.

* The simplest solution is to release them all and create new.

*/

- memset(tcg_ctx->free_temps, 0, sizeof(tcg_ctx->free_temps));

+ tcg_temp_ebb_reset_freed(tcg_ctx);

QTAILQ_FOREACH_SAFE(op, &tcg_ctx->ops, link, next) {

switch (op->opc) {

diff --git a/tcg/tcg.c b/tcg/tcg.c

index XXXXXXX..XXXXXXX 100644

--- a/tcg/tcg.c

+++ b/tcg/tcg.c

@@ -XXX,XX +XXX,XX @@ void tcg_func_start(TCGContext *s)

s->nb_temps = s->nb_globals;

/* No temps have been previously allocated for size or locality. */

- memset(s->free_temps, 0, sizeof(s->free_temps));

+ tcg_temp_ebb_reset_freed(s);

/* No constant temps have been previously allocated. */

for (int i = 0; i < TCG_TYPE_COUNT; ++i) {

@@ -XXX,XX +XXX,XX @@ int tcg_gen_code(TCGContext *s, TranslationBlock *tb, uint64_t pc_start)

#endif

+ /* Do not reuse any EBB that may be allocated within the TB. */

+ tcg_temp_ebb_reset_freed(s);

+

tcg_optimize(s);

reachable_code_pass(s);