qemu/include/exec/translation-block.h

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/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
* Definition of TranslationBlock.
* Copyright (c) 2003 Fabrice Bellard
*/
#ifndef EXEC_TRANSLATION_BLOCK_H
#define EXEC_TRANSLATION_BLOCK_H
#include "qemu/thread.h"
#include "exec/cpu-common.h"
#ifdef CONFIG_USER_ONLY
#include "qemu/interval-tree.h"
#endif
/*
* Page tracking code uses ram addresses in system mode, and virtual
* addresses in userspace mode. Define tb_page_addr_t to be an
* appropriate type.
*/
#if defined(CONFIG_USER_ONLY)
typedef vaddr tb_page_addr_t;
#define TB_PAGE_ADDR_FMT "%" VADDR_PRIx
#else
typedef ram_addr_t tb_page_addr_t;
#define TB_PAGE_ADDR_FMT RAM_ADDR_FMT
#endif
/*
* Translation Cache-related fields of a TB.
* This struct exists just for convenience; we keep track of TB's in a binary
* search tree, and the only fields needed to compare TB's in the tree are
* @ptr and @size.
* Note: the address of search data can be obtained by adding @size to @ptr.
*/
struct tb_tc {
const void *ptr; /* pointer to the translated code */
size_t size;
};
struct TranslationBlock {
/*
* Guest PC corresponding to this block. This must be the true
* virtual address. Therefore e.g. x86 stores EIP + CS_BASE, and
* targets like Arm, MIPS, HP-PA, which reuse low bits for ISA or
* privilege, must store those bits elsewhere.
*
* If CF_PCREL, the opcodes for the TranslationBlock are written
* such that the TB is associated only with the physical page and
* may be run in any virtual address context. In this case, PC
* must always be taken from ENV in a target-specific manner.
* Unwind information is taken as offsets from the page, to be
* deposited into the "current" PC.
*/
vaddr pc;
/*
* Target-specific data associated with the TranslationBlock, e.g.:
* x86: the original user, the Code Segment virtual base,
* arm: an extension of tb->flags,
* s390x: instruction data for EXECUTE,
* sparc: the next pc of the instruction queue (for delay slots).
*/
uint64_t cs_base;
uint32_t flags; /* flags defining in which context the code was generated */
uint32_t cflags; /* compile flags */
/* Note that TCG_MAX_INSNS is 512; we validate this match elsewhere. */
#define CF_COUNT_MASK 0x000001ff
#define CF_NO_GOTO_TB 0x00000200 /* Do not chain with goto_tb */
#define CF_NO_GOTO_PTR 0x00000400 /* Do not chain with goto_ptr */
#define CF_SINGLE_STEP 0x00000800 /* gdbstub single-step in effect */
#define CF_MEMI_ONLY 0x00001000 /* Only instrument memory ops */
#define CF_USE_ICOUNT 0x00002000
#define CF_INVALID 0x00004000 /* TB is stale. Set with @jmp_lock held */
#define CF_PARALLEL 0x00008000 /* Generate code for a parallel context */
#define CF_NOIRQ 0x00010000 /* Generate an uninterruptible TB */
#define CF_PCREL 0x00020000 /* Opcodes in TB are PC-relative */
#define CF_BP_PAGE 0x00040000 /* Breakpoint present in code page */
#define CF_CLUSTER_MASK 0xff000000 /* Top 8 bits are cluster ID */
#define CF_CLUSTER_SHIFT 24
/*
* Above fields used for comparing
*/
/* size of target code for this block (1 <= size <= TARGET_PAGE_SIZE) */
uint16_t size;
uint16_t icount;
struct tb_tc tc;
/*
* Track tb_page_addr_t intervals that intersect this TB.
* For user-only, the virtual addresses are always contiguous,
* and we use a unified interval tree. For system, we use a
* linked list headed in each PageDesc. Within the list, the lsb
* of the previous pointer tells the index of page_next[], and the
* list is protected by the PageDesc lock(s).
*/
#ifdef CONFIG_USER_ONLY
IntervalTreeNode itree;
#else
uintptr_t page_next[2];
tb_page_addr_t page_addr[2];
#endif
/* jmp_lock placed here to fill a 4-byte hole. Its documentation is below */
QemuSpin jmp_lock;
/* The following data are used to directly call another TB from
* the code of this one. This can be done either by emitting direct or
* indirect native jump instructions. These jumps are reset so that the TB
* just continues its execution. The TB can be linked to another one by
* setting one of the jump targets (or patching the jump instruction). Only
* two of such jumps are supported.
*/
#define TB_JMP_OFFSET_INVALID 0xffff /* indicates no jump generated */
uint16_t jmp_reset_offset[2]; /* offset of original jump target */
uint16_t jmp_insn_offset[2]; /* offset of direct jump insn */
uintptr_t jmp_target_addr[2]; /* target address */
/*
* Each TB has a NULL-terminated list (jmp_list_head) of incoming jumps.
* Each TB can have two outgoing jumps, and therefore can participate
* in two lists. The list entries are kept in jmp_list_next[2]. The least
* significant bit (LSB) of the pointers in these lists is used to encode
* which of the two list entries is to be used in the pointed TB.
*
* List traversals are protected by jmp_lock. The destination TB of each
* outgoing jump is kept in jmp_dest[] so that the appropriate jmp_lock
* can be acquired from any origin TB.
*
* jmp_dest[] are tagged pointers as well. The LSB is set when the TB is
* being invalidated, so that no further outgoing jumps from it can be set.
*
* jmp_lock also protects the CF_INVALID cflag; a jump must not be chained
* to a destination TB that has CF_INVALID set.
*/
uintptr_t jmp_list_head;
uintptr_t jmp_list_next[2];
uintptr_t jmp_dest[2];
};
/* The alignment given to TranslationBlock during allocation. */
#define CODE_GEN_ALIGN 16
/* Hide the qatomic_read to make code a little easier on the eyes */
static inline uint32_t tb_cflags(const TranslationBlock *tb)
{
return qatomic_read(&tb->cflags);
}
#endif /* EXEC_TRANSLATION_BLOCK_H */