Richard Henderson <r...@twiddle.net> writes:
> Allow qemu to build on 32-bit hosts without 64-bit atomic ops.
>
> Even if we only allow 32-bit hosts to multi-thread emulate 32-bit
> guests, we still need some way to handle the 32-bit guest using a
> 64-bit atomic operation. Do so by dropping back to single-step.
>
> Signed-off-by: Richard Henderson <r...@twiddle.net>
Reviewed-by: Alex Bennée <alex.ben...@linaro.org>
> ---
> configure | 33 +++++++++++++++++++++++++++++++++
> cputlb.c | 4 ++++
> tcg-runtime.c | 7 +++++++
> tcg/tcg-op.c | 22 ++++++++++++++++++----
> tcg/tcg-runtime.h | 46 ++++++++++++++++++++++++++++++++++++++++------
> tcg/tcg.h | 15 ++++++++++++---
> 6 files changed, 114 insertions(+), 13 deletions(-)
>
> diff --git a/configure b/configure
> index 5b38357..0616043 100755
> --- a/configure
> +++ b/configure
> @@ -4501,6 +4501,35 @@ EOF
> fi
> fi
>
> +#########################################
> +# See if 64-bit atomic operations are supported.
> +# Note that without __atomic builtins, we can only
> +# assume atomic loads/stores max at pointer size.
> +
> +cat > $TMPC << EOF
> +#include <stdint.h>
> +int main(void)
> +{
> + uint64_t x = 0, y = 0;
> +#ifdef __ATOMIC_RELAXED
> + y = __atomic_load_8(&x, 0);
> + __atomic_store_8(&x, y, 0);
> + __atomic_compare_exchange_8(&x, &y, x, 0, 0, 0);
> + __atomic_exchange_8(&x, y, 0);
> + __atomic_fetch_add_8(&x, y, 0);
> +#else
> + typedef char is_host64[sizeof(void *) >= sizeof(uint64_t) ? 1 : -1];
> + __sync_lock_test_and_set(&x, y);
> + __sync_val_compare_and_swap(&x, y, 0);
> + __sync_fetch_and_add(&x, y);
> +#endif
> + return 0;
> +}
> +EOF
> +if compile_prog "" "" ; then
> + atomic64=yes
> +fi
> +
> ########################################
> # check if getauxval is available.
>
> @@ -5458,6 +5487,10 @@ if test "$atomic128" = "yes" ; then
> echo "CONFIG_ATOMIC128=y" >> $config_host_mak
> fi
>
> +if test "$atomic64" = "yes" ; then
> + echo "CONFIG_ATOMIC64=y" >> $config_host_mak
> +fi
> +
> if test "$getauxval" = "yes" ; then
> echo "CONFIG_GETAUXVAL=y" >> $config_host_mak
> fi
> diff --git a/cputlb.c b/cputlb.c
> index 845b2a7..cc4da4d 100644
> --- a/cputlb.c
> +++ b/cputlb.c
> @@ -687,8 +687,10 @@ static void *atomic_mmu_lookup(CPUArchState *env,
> target_ulong addr,
> #define DATA_SIZE 4
> #include "atomic_template.h"
>
> +#ifdef CONFIG_ATOMIC64
> #define DATA_SIZE 8
> #include "atomic_template.h"
> +#endif
>
> #ifdef CONFIG_ATOMIC128
> #define DATA_SIZE 16
> @@ -713,8 +715,10 @@ static void *atomic_mmu_lookup(CPUArchState *env,
> target_ulong addr,
> #define DATA_SIZE 4
> #include "atomic_template.h"
>
> +#ifdef CONFIG_ATOMIC64
> #define DATA_SIZE 8
> #include "atomic_template.h"
> +#endif
>
> /* Code access functions. */
>
> diff --git a/tcg-runtime.c b/tcg-runtime.c
> index e952153..9327b6f 100644
> --- a/tcg-runtime.c
> +++ b/tcg-runtime.c
> @@ -101,6 +101,11 @@ int64_t HELPER(mulsh_i64)(int64_t arg1, int64_t arg2)
> return h;
> }
>
> +void HELPER(exit_atomic)(CPUArchState *env)
> +{
> + cpu_loop_exit_atomic(ENV_GET_CPU(env), GETPC());
> +}
> +
> #ifndef CONFIG_SOFTMMU
> /* The softmmu versions of these helpers are in cputlb.c. */
>
> @@ -130,8 +135,10 @@ static void *atomic_mmu_lookup(CPUArchState *env,
> target_ulong addr,
> #define DATA_SIZE 4
> #include "atomic_template.h"
>
> +#ifdef CONFIG_ATOMIC64
> #define DATA_SIZE 8
> #include "atomic_template.h"
> +#endif
>
> /* The following is only callable from other helpers, and matches up
> with the softmmu version. */
> diff --git a/tcg/tcg-op.c b/tcg/tcg-op.c
> index 65e3663..cdd61d6 100644
> --- a/tcg/tcg-op.c
> +++ b/tcg/tcg-op.c
> @@ -2040,14 +2040,20 @@ typedef void (*gen_atomic_op_i32)(TCGv_i32, TCGv_env,
> TCGv, TCGv_i32);
> typedef void (*gen_atomic_op_i64)(TCGv_i64, TCGv_env, TCGv, TCGv_i64);
> #endif
>
> +#ifdef CONFIG_ATOMIC64
> +# define WITH_ATOMIC64(X) X,
> +#else
> +# define WITH_ATOMIC64(X)
> +#endif
> +
> static void * const table_cmpxchg[16] = {
> [MO_8] = gen_helper_atomic_cmpxchgb,
> [MO_16 | MO_LE] = gen_helper_atomic_cmpxchgw_le,
> [MO_16 | MO_BE] = gen_helper_atomic_cmpxchgw_be,
> [MO_32 | MO_LE] = gen_helper_atomic_cmpxchgl_le,
> [MO_32 | MO_BE] = gen_helper_atomic_cmpxchgl_be,
> - [MO_64 | MO_LE] = gen_helper_atomic_cmpxchgq_le,
> - [MO_64 | MO_BE] = gen_helper_atomic_cmpxchgq_be,
> + WITH_ATOMIC64([MO_64 | MO_LE] = gen_helper_atomic_cmpxchgq_le)
> + WITH_ATOMIC64([MO_64 | MO_BE] = gen_helper_atomic_cmpxchgq_be)
> };
>
> void tcg_gen_atomic_cmpxchg_i32(TCGv_i32 retv, TCGv addr, TCGv_i32 cmpv,
> @@ -2117,6 +2123,7 @@ void tcg_gen_atomic_cmpxchg_i64(TCGv_i64 retv, TCGv
> addr, TCGv_i64 cmpv,
> }
> tcg_temp_free_i64(t1);
> } else if ((memop & MO_SIZE) == MO_64) {
> +#ifdef CONFIG_ATOMIC64
> gen_atomic_cx_i64 gen;
>
> gen = table_cmpxchg[memop & (MO_SIZE | MO_BSWAP)];
> @@ -2131,6 +2138,9 @@ void tcg_gen_atomic_cmpxchg_i64(TCGv_i64 retv, TCGv
> addr, TCGv_i64 cmpv,
> #else
> gen(retv, tcg_ctx.tcg_env, addr, cmpv, newv);
> #endif
> +#else
> + gen_helper_exit_atomic(tcg_ctx.tcg_env);
> +#endif /* CONFIG_ATOMIC64 */
> } else {
> TCGv_i32 c32 = tcg_temp_new_i32();
> TCGv_i32 n32 = tcg_temp_new_i32();
> @@ -2218,6 +2228,7 @@ static void do_atomic_op_i64(TCGv_i64 ret, TCGv addr,
> TCGv_i64 val,
> memop = tcg_canonicalize_memop(memop, 1, 0);
>
> if ((memop & MO_SIZE) == MO_64) {
> +#ifdef CONFIG_ATOMIC64
> gen_atomic_op_i64 gen;
>
> gen = table[memop & (MO_SIZE | MO_BSWAP)];
> @@ -2232,6 +2243,9 @@ static void do_atomic_op_i64(TCGv_i64 ret, TCGv addr,
> TCGv_i64 val,
> #else
> gen(ret, tcg_ctx.tcg_env, addr, val);
> #endif
> +#else
> + gen_helper_exit_atomic(tcg_ctx.tcg_env);
> +#endif /* CONFIG_ATOMIC64 */
> } else {
> TCGv_i32 v32 = tcg_temp_new_i32();
> TCGv_i32 r32 = tcg_temp_new_i32();
> @@ -2256,8 +2270,8 @@ static void * const table_##NAME[16] = {
> \
> [MO_16 | MO_BE] = gen_helper_atomic_##NAME##w_be, \
> [MO_32 | MO_LE] = gen_helper_atomic_##NAME##l_le, \
> [MO_32 | MO_BE] = gen_helper_atomic_##NAME##l_be, \
> - [MO_64 | MO_LE] = gen_helper_atomic_##NAME##q_le, \
> - [MO_64 | MO_BE] = gen_helper_atomic_##NAME##q_be, \
> + WITH_ATOMIC64([MO_64 | MO_LE] = gen_helper_atomic_##NAME##q_le) \
> + WITH_ATOMIC64([MO_64 | MO_BE] = gen_helper_atomic_##NAME##q_be) \
> }; \
> void tcg_gen_atomic_##NAME##_i32 \
> (TCGv_i32 ret, TCGv addr, TCGv_i32 val, TCGArg idx, TCGMemOp memop) \
> diff --git a/tcg/tcg-runtime.h b/tcg/tcg-runtime.h
> index 22367aa..1deb86a 100644
> --- a/tcg/tcg-runtime.h
> +++ b/tcg/tcg-runtime.h
> @@ -15,23 +15,28 @@ DEF_HELPER_FLAGS_2(sar_i64, TCG_CALL_NO_RWG_SE, s64, s64,
> s64)
> DEF_HELPER_FLAGS_2(mulsh_i64, TCG_CALL_NO_RWG_SE, s64, s64, s64)
> DEF_HELPER_FLAGS_2(muluh_i64, TCG_CALL_NO_RWG_SE, i64, i64, i64)
>
> +DEF_HELPER_FLAGS_1(exit_atomic, TCG_CALL_NO_WG, noreturn, env)
> +
> #ifdef CONFIG_SOFTMMU
>
> DEF_HELPER_FLAGS_5(atomic_cmpxchgb, TCG_CALL_NO_WG,
> i32, env, tl, i32, i32, i32)
> DEF_HELPER_FLAGS_5(atomic_cmpxchgw_be, TCG_CALL_NO_WG,
> i32, env, tl, i32, i32, i32)
> -DEF_HELPER_FLAGS_5(atomic_cmpxchgl_be, TCG_CALL_NO_WG,
> - i32, env, tl, i32, i32, i32)
> -DEF_HELPER_FLAGS_5(atomic_cmpxchgq_be, TCG_CALL_NO_WG,
> - i64, env, tl, i64, i64, i32)
> DEF_HELPER_FLAGS_5(atomic_cmpxchgw_le, TCG_CALL_NO_WG,
> i32, env, tl, i32, i32, i32)
> +DEF_HELPER_FLAGS_5(atomic_cmpxchgl_be, TCG_CALL_NO_WG,
> + i32, env, tl, i32, i32, i32)
> DEF_HELPER_FLAGS_5(atomic_cmpxchgl_le, TCG_CALL_NO_WG,
> i32, env, tl, i32, i32, i32)
> +#ifdef CONFIG_ATOMIC64
> +DEF_HELPER_FLAGS_5(atomic_cmpxchgq_be, TCG_CALL_NO_WG,
> + i64, env, tl, i64, i64, i32)
> DEF_HELPER_FLAGS_5(atomic_cmpxchgq_le, TCG_CALL_NO_WG,
> i64, env, tl, i64, i64, i32)
> +#endif
>
> +#ifdef CONFIG_ATOMIC64
> #define GEN_ATOMIC_HELPERS(NAME) \
> DEF_HELPER_FLAGS_4(glue(glue(atomic_, NAME), b), \
> TCG_CALL_NO_WG, i32, env, tl, i32, i32) \
> @@ -47,17 +52,33 @@ DEF_HELPER_FLAGS_5(atomic_cmpxchgq_le, TCG_CALL_NO_WG,
> TCG_CALL_NO_WG, i64, env, tl, i64, i32) \
> DEF_HELPER_FLAGS_4(glue(glue(atomic_, NAME), q_be), \
> TCG_CALL_NO_WG, i64, env, tl, i64, i32)
> +#else
> +#define GEN_ATOMIC_HELPERS(NAME) \
> + DEF_HELPER_FLAGS_4(glue(glue(atomic_, NAME), b), \
> + TCG_CALL_NO_WG, i32, env, tl, i32, i32) \
> + DEF_HELPER_FLAGS_4(glue(glue(atomic_, NAME), w_le), \
> + TCG_CALL_NO_WG, i32, env, tl, i32, i32) \
> + DEF_HELPER_FLAGS_4(glue(glue(atomic_, NAME), w_be), \
> + TCG_CALL_NO_WG, i32, env, tl, i32, i32) \
> + DEF_HELPER_FLAGS_4(glue(glue(atomic_, NAME), l_le), \
> + TCG_CALL_NO_WG, i32, env, tl, i32, i32) \
> + DEF_HELPER_FLAGS_4(glue(glue(atomic_, NAME), l_be), \
> + TCG_CALL_NO_WG, i32, env, tl, i32, i32)
> +#endif /* CONFIG_ATOMIC64 */
>
> #else
>
> DEF_HELPER_FLAGS_4(atomic_cmpxchgb, TCG_CALL_NO_WG, i32, env, tl, i32, i32)
> DEF_HELPER_FLAGS_4(atomic_cmpxchgw_be, TCG_CALL_NO_WG, i32, env, tl, i32,
> i32)
> -DEF_HELPER_FLAGS_4(atomic_cmpxchgl_be, TCG_CALL_NO_WG, i32, env, tl, i32,
> i32)
> -DEF_HELPER_FLAGS_4(atomic_cmpxchgq_be, TCG_CALL_NO_WG, i64, env, tl, i64,
> i64)
> DEF_HELPER_FLAGS_4(atomic_cmpxchgw_le, TCG_CALL_NO_WG, i32, env, tl, i32,
> i32)
> +DEF_HELPER_FLAGS_4(atomic_cmpxchgl_be, TCG_CALL_NO_WG, i32, env, tl, i32,
> i32)
> DEF_HELPER_FLAGS_4(atomic_cmpxchgl_le, TCG_CALL_NO_WG, i32, env, tl, i32,
> i32)
> +#ifdef CONFIG_ATOMIC64
> +DEF_HELPER_FLAGS_4(atomic_cmpxchgq_be, TCG_CALL_NO_WG, i64, env, tl, i64,
> i64)
> DEF_HELPER_FLAGS_4(atomic_cmpxchgq_le, TCG_CALL_NO_WG, i64, env, tl, i64,
> i64)
> +#endif
>
> +#ifdef CONFIG_ATOMIC64
> #define GEN_ATOMIC_HELPERS(NAME) \
> DEF_HELPER_FLAGS_3(glue(glue(atomic_, NAME), b), \
> TCG_CALL_NO_WG, i32, env, tl, i32) \
> @@ -73,6 +94,19 @@ DEF_HELPER_FLAGS_4(atomic_cmpxchgq_le, TCG_CALL_NO_WG,
> i64, env, tl, i64, i64)
> TCG_CALL_NO_WG, i64, env, tl, i64) \
> DEF_HELPER_FLAGS_3(glue(glue(atomic_, NAME), q_be), \
> TCG_CALL_NO_WG, i64, env, tl, i64)
> +#else
> +#define GEN_ATOMIC_HELPERS(NAME) \
> + DEF_HELPER_FLAGS_3(glue(glue(atomic_, NAME), b), \
> + TCG_CALL_NO_WG, i32, env, tl, i32) \
> + DEF_HELPER_FLAGS_3(glue(glue(atomic_, NAME), w_le), \
> + TCG_CALL_NO_WG, i32, env, tl, i32) \
> + DEF_HELPER_FLAGS_3(glue(glue(atomic_, NAME), w_be), \
> + TCG_CALL_NO_WG, i32, env, tl, i32) \
> + DEF_HELPER_FLAGS_3(glue(glue(atomic_, NAME), l_le), \
> + TCG_CALL_NO_WG, i32, env, tl, i32) \
> + DEF_HELPER_FLAGS_3(glue(glue(atomic_, NAME), l_be), \
> + TCG_CALL_NO_WG, i32, env, tl, i32)
> +#endif /* CONFIG_ATOMIC64 */
>
> #endif /* CONFIG_SOFTMMU */
>
> diff --git a/tcg/tcg.h b/tcg/tcg.h
> index bc3ea7a..b34b5fb 100644
> --- a/tcg/tcg.h
> +++ b/tcg/tcg.h
> @@ -1204,14 +1204,23 @@ TYPE helper_atomic_ ## NAME ## SUFFIX ## _mmu
> \
> (CPUArchState *env, target_ulong addr, TYPE val, \
> TCGMemOpIdx oi, uintptr_t retaddr);
>
> +#ifdef CONFIG_ATOMIC64
> #define GEN_ATOMIC_HELPER_ALL(NAME) \
> - GEN_ATOMIC_HELPER(NAME, uint32_t, b) \
> + GEN_ATOMIC_HELPER(NAME, uint32_t, b) \
> GEN_ATOMIC_HELPER(NAME, uint32_t, w_le) \
> - GEN_ATOMIC_HELPER(NAME, uint32_t, l_le) \
> - GEN_ATOMIC_HELPER(NAME, uint64_t, q_le) \
> GEN_ATOMIC_HELPER(NAME, uint32_t, w_be) \
> + GEN_ATOMIC_HELPER(NAME, uint32_t, l_le) \
> GEN_ATOMIC_HELPER(NAME, uint32_t, l_be) \
> + GEN_ATOMIC_HELPER(NAME, uint64_t, q_le) \
> GEN_ATOMIC_HELPER(NAME, uint64_t, q_be)
> +#else
> +#define GEN_ATOMIC_HELPER_ALL(NAME) \
> + GEN_ATOMIC_HELPER(NAME, uint32_t, b) \
> + GEN_ATOMIC_HELPER(NAME, uint32_t, w_le) \
> + GEN_ATOMIC_HELPER(NAME, uint32_t, w_be) \
> + GEN_ATOMIC_HELPER(NAME, uint32_t, l_le) \
> + GEN_ATOMIC_HELPER(NAME, uint32_t, l_be)
> +#endif
>
> GEN_ATOMIC_HELPER_ALL(fetch_add)
> GEN_ATOMIC_HELPER_ALL(fetch_sub)
--
Alex Bennée
