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-rw-r--r--include/exec/translation-block.h149
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diff --git a/include/exec/translation-block.h b/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/atomic.h"
+#include "qemu/thread.h"
+#include "qemu/interval-tree.h"
+#include "exec/cpu-common.h"
+#include "exec/target_page.h"
+
+/*
+ * 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_LAST_IO       0x00008000 /* Last insn may be an IO access.  */
+#define CF_MEMI_ONLY     0x00010000 /* Only instrument memory ops */
+#define CF_USE_ICOUNT    0x00020000
+#define CF_INVALID       0x00040000 /* TB is stale. Set with @jmp_lock held */
+#define CF_PARALLEL      0x00080000 /* Generate code for a parallel context */
+#define CF_NOIRQ         0x00100000 /* Generate an uninterruptible TB */
+#define CF_PCREL         0x00200000 /* Opcodes in TB are PC-relative */
+#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
+
+#endif /* EXEC_TRANSLATION_BLOCK_H */