diff options
| author | Richard Henderson <richard.henderson@linaro.org> | 2020-10-29 13:18:12 -0700 |
|---|---|---|
| committer | Richard Henderson <richard.henderson@linaro.org> | 2021-01-07 05:09:42 -1000 |
| commit | eba40358b49cb09f4e24764db7951e30987aa416 (patch) | |
| tree | 4a111ea02edb581121c68d29d1b80657d24f5f28 /tcg | |
| parent | 6f70ddee19ec7837812bda81cec59dc2681df0a9 (diff) | |
tcg: Return the TB pointer from the rx region from exit_tb
This produces a small pc-relative displacement within the
generated code to the TB structure that preceeds it.
Reviewed-by: Joelle van Dyne <j@getutm.app>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Diffstat (limited to 'tcg')
| -rw-r--r-- | tcg/tcg-op.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/tcg/tcg-op.c b/tcg/tcg-op.c index 19fa8e4691..0374b5d56d 100644 --- a/tcg/tcg-op.c +++ b/tcg/tcg-op.c @@ -2666,7 +2666,18 @@ void tcg_gen_extr32_i64(TCGv_i64 lo, TCGv_i64 hi, TCGv_i64 arg) void tcg_gen_exit_tb(const TranslationBlock *tb, unsigned idx) { - uintptr_t val = (uintptr_t)tb + idx; + /* + * Let the jit code return the read-only version of the + * TranslationBlock, so that we minimize the pc-relative + * distance of the address of the exit_tb code to TB. + * This will improve utilization of pc-relative address loads. + * + * TODO: Move this to translator_loop, so that all const + * TranslationBlock pointers refer to read-only memory. + * This requires coordination with targets that do not use + * the translator_loop. + */ + uintptr_t val = (uintptr_t)tcg_splitwx_to_rx((void *)tb) + idx; if (tb == NULL) { tcg_debug_assert(idx == 0); |