ShuriZma
/
xemu
mirror of https://github.com/xemu-project/xemu.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

tcg: Add in_code_gen_buffer 

Create a function to determine if a pointer is within the buffer.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2020-10-30 18:59:09 -07:00
parent 8b5c2b6260
commit 4846cd37df
2 changed files with 19 additions and 18 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
accel/tcg/translate-all.c
View File

@ -392,27 +392,18 @@ void tb_destroy(TranslationBlock *tb)
bool cpu_restore_state(CPUState *cpu, uintptr_t host_pc, bool will_exit) bool cpu_restore_state(CPUState *cpu, uintptr_t host_pc, bool will_exit)
{ {
TranslationBlock *tb; /*
bool r = false; * The host_pc has to be in the region of the code buffer.
uintptr_t check_offset; * If it is not we will not be able to resolve it here.
* The two cases where host_pc will not be correct are:
/* The host_pc has to be in the region of current code buffer. If
* it is not we will not be able to resolve it here. The two cases
* where host_pc will not be correct are:
* *
* - fault during translation (instruction fetch) * - fault during translation (instruction fetch)
* - fault from helper (not using GETPC() macro) * - fault from helper (not using GETPC() macro)
* *
* Either way we need return early as we can't resolve it here. * Either way we need return early as we can't resolve it here.
*
* We are using unsigned arithmetic so if host_pc <
* tcg_init_ctx.code_gen_buffer check_offset will wrap to way
* above the code_gen_buffer_size
*/ */
check_offset = host_pc - (uintptr_t) tcg_init_ctx.code_gen_buffer; if (in_code_gen_buffer((const void *)host_pc)) {
TranslationBlock *tb = tcg_tb_lookup(host_pc);
if (check_offset < tcg_init_ctx.code_gen_buffer_size) {
tb = tcg_tb_lookup(host_pc);
if (tb) { if (tb) {
cpu_restore_state_from_tb(cpu, tb, host_pc, will_exit); cpu_restore_state_from_tb(cpu, tb, host_pc, will_exit);
if (tb_cflags(tb) & CF_NOCACHE) { if (tb_cflags(tb) & CF_NOCACHE) {
@ -421,11 +412,10 @@ bool cpu_restore_state(CPUState *cpu, uintptr_t host_pc, bool will_exit)
tcg_tb_remove(tb); tcg_tb_remove(tb);
tb_destroy(tb); tb_destroy(tb);
} }
r = true; return true;
} }
} }
return false;
return r;
} }
static void page_init(void) static void page_init(void)

11
include/tcg/tcg.h
View File

@ -680,6 +680,17 @@ extern __thread TCGContext *tcg_ctx;
extern void *tcg_code_gen_epilogue; extern void *tcg_code_gen_epilogue;
extern TCGv_env cpu_env; extern TCGv_env cpu_env;
static inline bool in_code_gen_buffer(const void *p)
{
const TCGContext *s = &tcg_init_ctx;
/*
* Much like it is valid to have a pointer to the byte past the
* end of an array (so long as you don't dereference it), allow
* a pointer to the byte past the end of the code gen buffer.
*/
return (size_t)(p - s->code_gen_buffer) <= s->code_gen_buffer_size;
}
static inline size_t temp_idx(TCGTemp *ts) static inline size_t temp_idx(TCGTemp *ts)
{ {
ptrdiff_t n = ts - tcg_ctx->temps; ptrdiff_t n = ts - tcg_ctx->temps;