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/*
* softmmu size bounds
* SPDX-License-Identifier: LGPL-2.1-or-later
*/
#ifndef ACCEL_TCG_TLB_BOUNDS_H
#define ACCEL_TCG_TLB_BOUNDS_H
#define CPU_TLB_DYN_MIN_BITS 6
#define CPU_TLB_DYN_DEFAULT_BITS 8
# if HOST_LONG_BITS == 32
/* Make sure we do not require a double-word shift for the TLB load */
# define CPU_TLB_DYN_MAX_BITS (32 - TARGET_PAGE_BITS)
# else /* HOST_LONG_BITS == 64 */
/*
* Assuming TARGET_PAGE_BITS==12, with 2**22 entries we can cover 2**(22+12) ==
* 2**34 == 16G of address space. This is roughly what one would expect a
* TLB to cover in a modern (as of 2018) x86_64 CPU. For instance, Intel
* Skylake's Level-2 STLB has 16 1G entries.
* Also, make sure we do not size the TLB past the guest's address space.
*/
# ifdef TARGET_PAGE_BITS_VARY
# define CPU_TLB_DYN_MAX_BITS \
MIN(22, TARGET_VIRT_ADDR_SPACE_BITS - TARGET_PAGE_BITS)
# else
# define CPU_TLB_DYN_MAX_BITS \
MIN_CONST(22, TARGET_VIRT_ADDR_SPACE_BITS - TARGET_PAGE_BITS)
# endif
# endif
#endif /* ACCEL_TCG_TLB_BOUNDS_H */
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