tcg-s390: Allocate the code_gen_buffer near the main program.

This allows the use of direct calls to the helpers,
and a direct branch back to the epilogue.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
This commit is contained in:
Richard Henderson 2010-06-04 12:14:14 -07:00 committed by Aurelien Jarno
parent 1bcaae666f
commit eba0b89379
1 changed files with 7 additions and 0 deletions

7
exec.c
View File

@ -519,6 +519,13 @@ static void code_gen_alloc(unsigned long tb_size)
start = (void *) 0x01000000UL;
if (code_gen_buffer_size > 16 * 1024 * 1024)
code_gen_buffer_size = 16 * 1024 * 1024;
#elif defined(__s390x__)
/* Map the buffer so that we can use direct calls and branches. */
/* We have a +- 4GB range on the branches; leave some slop. */
if (code_gen_buffer_size > (3ul * 1024 * 1024 * 1024)) {
code_gen_buffer_size = 3ul * 1024 * 1024 * 1024;
}
start = (void *)0x90000000UL;
#endif
code_gen_buffer = mmap(start, code_gen_buffer_size,
PROT_WRITE | PROT_READ | PROT_EXEC,