tcg.c

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/*
 * Tiny Code Generator for QEMU
 *
 * Copyright (c) 2008 Fabrice Bellard
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

/* define it to suppress various consistency checks (faster) */
#define NDEBUG

/* define it to use liveness analysis (better code) */
#define USE_LIVENESS_ANALYSIS

#include <assert.h>
#include <stdarg.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <inttypes.h>
#ifdef _WIN32
#include <malloc.h>
#endif

#include "config.h"
#include "qemu-common.h"

/* Note: the long term plan is to reduce the dependancies on the QEMU
   CPU definitions. Currently they are used for qemu_ld/st
   instructions */
#define NO_CPU_IO_DEFS
#include "cpu.h"
#include "exec-all.h"

#include "tcg-op.h"
#include "elf.h"


static void patch_reloc(uint8_t *code_ptr, int type, 
                        tcg_target_long value, tcg_target_long addend);

TCGOpDef tcg_op_defs[] = {
#define DEF(s, n, copy_size) { #s, 0, 0, n, n, 0, copy_size },
#define DEF2(s, iargs, oargs, cargs, flags) { #s, iargs, oargs, cargs, iargs + oargs + cargs, flags, 0 },
#include "tcg-opc.h"
#undef DEF
#undef DEF2
};

TCGRegSet tcg_target_available_regs[2];
TCGRegSet tcg_target_call_clobber_regs;

/* XXX: move that inside the context */
uint16_t *gen_opc_ptr;
TCGArg *gen_opparam_ptr;

static inline void tcg_out8(TCGContext *s, uint8_t v)
{
    *s->code_ptr++ = v;
}

static inline void tcg_out16(TCGContext *s, uint16_t v)
{
    *(uint16_t *)s->code_ptr = v;
    s->code_ptr += 2;
}

static inline void tcg_out32(TCGContext *s, uint32_t v)
{
    *(uint32_t *)s->code_ptr = v;
    s->code_ptr += 4;
}

/* label relocation processing */

void tcg_out_reloc(TCGContext *s, uint8_t *code_ptr, int type, 
                   int label_index, long addend)
{
    TCGLabel *l;
    TCGRelocation *r;

    l = &s->labels[label_index];
    if (l->has_value) {
        /* FIXME: This may break relocations on RISC targets that
           modify instruction fields in place.  The caller may not have 
           written the initial value.  */
        patch_reloc(code_ptr, type, l->u.value, addend);
    } else {
        /* add a new relocation entry */
        r = tcg_malloc(sizeof(TCGRelocation));
        r->type = type;
        r->ptr = code_ptr;
        r->addend = addend;
        r->next = l->u.first_reloc;
        l->u.first_reloc = r;
    }
}

static void tcg_out_label(TCGContext *s, int label_index, 
                          tcg_target_long value)
{
    TCGLabel *l;
    TCGRelocation *r;

    l = &s->labels[label_index];
    if (l->has_value)
        tcg_abort();
    r = l->u.first_reloc;
    while (r != NULL) {
        patch_reloc(r->ptr, r->type, value, r->addend);
        r = r->next;
    }
    l->has_value = 1;
    l->u.value = value;
}

int gen_new_label(void)
{
    TCGContext *s = &tcg_ctx;
    int idx;
    TCGLabel *l;

    if (s->nb_labels >= TCG_MAX_LABELS)
        tcg_abort();
    idx = s->nb_labels++;
    l = &s->labels[idx];
    l->has_value = 0;
    l->u.first_reloc = NULL;
    return idx;
}

#include "tcg-target.c"

/* pool based memory allocation */
void *tcg_malloc_internal(TCGContext *s, int size)
{
    TCGPool *p;
    int pool_size;
    
    if (size > TCG_POOL_CHUNK_SIZE) {
        /* big malloc: insert a new pool (XXX: could optimize) */
        p = qemu_malloc(sizeof(TCGPool) + size);
        p->size = size;
        if (s->pool_current)
            s->pool_current->next = p;
        else
            s->pool_first = p;
        p->next = s->pool_current;
    } else {
        p = s->pool_current;
        if (!p) {
            p = s->pool_first;
            if (!p)
                goto new_pool;
        } else {
            if (!p->next) {
            new_pool:
                pool_size = TCG_POOL_CHUNK_SIZE;
                p = qemu_malloc(sizeof(TCGPool) + pool_size);
                p->size = pool_size;
                p->next = NULL;
                if (s->pool_current) 
                    s->pool_current->next = p;
                else
                    s->pool_first = p;
            } else {
                p = p->next;
            }
        }
    }
    s->pool_current = p;
    s->pool_cur = p->data + size;
    s->pool_end = p->data + p->size;
    return p->data;
}

void tcg_pool_reset(TCGContext *s)
{
    s->pool_cur = s->pool_end = NULL;
    s->pool_current = NULL;
}

/* free all the pool */
void tcg_pool_free(TCGContext *s)
{
    TCGPool *p, *p1;

    for(p = s->pool_first; p != NULL; p = p1) {
        p1 = p->next;
        qemu_free(p);
    }
    s->pool_first = NULL;
    s->pool_cur = s->pool_end = NULL;
}

void tcg_context_init(TCGContext *s)
{
    int op, total_args, n;
    TCGOpDef *def;
    TCGArgConstraint *args_ct;
    int *sorted_args;

    memset(s, 0, sizeof(*s));
    s->temps = s->static_temps;
    s->nb_globals = 0;
    
    /* Count total number of arguments and allocate the corresponding
       space */
    total_args = 0;
    for(op = 0; op < NB_OPS; op++) {
        def = &tcg_op_defs[op];
        n = def->nb_iargs + def->nb_oargs;
        total_args += n;
    }

    args_ct = qemu_malloc(sizeof(TCGArgConstraint) * total_args);
    sorted_args = qemu_malloc(sizeof(int) * total_args);

    for(op = 0; op < NB_OPS; op++) {
        def = &tcg_op_defs[op];
        def->args_ct = args_ct;
        def->sorted_args = sorted_args;
        n = def->nb_iargs + def->nb_oargs;
        sorted_args += n;
        args_ct += n;
    }
    
    tcg_target_init(s);

    /* init global prologue and epilogue */
    s->code_buf = code_gen_prologue;
    s->code_ptr = s->code_buf;
    tcg_target_qemu_prologue(s);
    flush_icache_range((unsigned long)s->code_buf, 
                       (unsigned long)s->code_ptr);
}

void tcg_set_frame(TCGContext *s, int reg,
                   tcg_target_long start, tcg_target_long size)
{
    s->frame_start = start;
    s->frame_end = start + size;
    s->frame_reg = reg;
}

void tcg_set_macro_func(TCGContext *s, TCGMacroFunc *func)
{
    s->macro_func = func;
}

void tcg_func_start(TCGContext *s)
{
    tcg_pool_reset(s);
    s->nb_temps = s->nb_globals;
    s->labels = tcg_malloc(sizeof(TCGLabel) * TCG_MAX_LABELS);
    s->nb_labels = 0;
    s->current_frame_offset = s->frame_start;

    gen_opc_ptr = gen_opc_buf;
    gen_opparam_ptr = gen_opparam_buf;
}

static inline void tcg_temp_alloc(TCGContext *s, int n)
{
    if (n > TCG_MAX_TEMPS)
        tcg_abort();
}

TCGv tcg_global_reg_new(TCGType type, int reg, const char *name)
{
    TCGContext *s = &tcg_ctx;
    TCGTemp *ts;
    int idx;

#if TCG_TARGET_REG_BITS == 32
    if (type != TCG_TYPE_I32)
        tcg_abort();
#endif
    if (tcg_regset_test_reg(s->reserved_regs, reg))
        tcg_abort();
    idx = s->nb_globals;
    tcg_temp_alloc(s, s->nb_globals + 1);
    ts = &s->temps[s->nb_globals];
    ts->base_type = type;
    ts->type = type;
    ts->fixed_reg = 1;
    ts->reg = reg;
    ts->val_type = TEMP_VAL_REG;
    ts->name = name;
    s->nb_globals++;
    tcg_regset_set_reg(s->reserved_regs, reg);
    return MAKE_TCGV(idx);
}

#if TCG_TARGET_REG_BITS == 32
/* temporary hack to avoid register shortage for tcg_qemu_st64() */
TCGv tcg_global_reg2_new_hack(TCGType type, int reg1, int reg2, 
                              const char *name)
{
    TCGContext *s = &tcg_ctx;
    TCGTemp *ts;
    int idx;
    char buf[64];

    if (type != TCG_TYPE_I64)
        tcg_abort();
    idx = s->nb_globals;
    tcg_temp_alloc(s, s->nb_globals + 2);
    ts = &s->temps[s->nb_globals];
    ts->base_type = type;
    ts->type = TCG_TYPE_I32;
    ts->fixed_reg = 1;
    ts->reg = reg1;
    ts->val_type = TEMP_VAL_REG;
    pstrcpy(buf, sizeof(buf), name);
    pstrcat(buf, sizeof(buf), "_0");
    ts->name = strdup(buf);

    ts++;
    ts->base_type = type;
    ts->type = TCG_TYPE_I32;
    ts->fixed_reg = 1;
    ts->reg = reg2;
    ts->val_type = TEMP_VAL_REG;
    pstrcpy(buf, sizeof(buf), name);
    pstrcat(buf, sizeof(buf), "_1");
    ts->name = strdup(buf);

    s->nb_globals += 2;
    return MAKE_TCGV(idx);
}
#endif

TCGv tcg_global_mem_new(TCGType type, int reg, tcg_target_long offset,
                        const char *name)
{
    TCGContext *s = &tcg_ctx;
    TCGTemp *ts;
    int idx;

    idx = s->nb_globals;
#if TCG_TARGET_REG_BITS == 32
    if (type == TCG_TYPE_I64) {
        char buf[64];
        tcg_temp_alloc(s, s->nb_globals + 1);
        ts = &s->temps[s->nb_globals];
        ts->base_type = type;
        ts->type = TCG_TYPE_I32;
        ts->fixed_reg = 0;
        ts->mem_allocated = 1;
        ts->mem_reg = reg;
#ifdef TCG_TARGET_WORDS_BIGENDIAN
        ts->mem_offset = offset + 4;
#else
        ts->mem_offset = offset;
#endif
        ts->val_type = TEMP_VAL_MEM;
        pstrcpy(buf, sizeof(buf), name);
        pstrcat(buf, sizeof(buf), "_0");
        ts->name = strdup(buf);
        ts++;

        ts->base_type = type;
        ts->type = TCG_TYPE_I32;
        ts->fixed_reg = 0;
        ts->mem_allocated = 1;
        ts->mem_reg = reg;
#ifdef TCG_TARGET_WORDS_BIGENDIAN
        ts->mem_offset = offset;
#else
        ts->mem_offset = offset + 4;
#endif
        ts->val_type = TEMP_VAL_MEM;
        pstrcpy(buf, sizeof(buf), name);
        pstrcat(buf, sizeof(buf), "_1");
        ts->name = strdup(buf);

        s->nb_globals += 2;
    } else
#endif
    {
        tcg_temp_alloc(s, s->nb_globals + 1);
        ts = &s->temps[s->nb_globals];
        ts->base_type = type;
        ts->type = type;
        ts->fixed_reg = 0;
        ts->mem_allocated = 1;
        ts->mem_reg = reg;
        ts->mem_offset = offset;
        ts->val_type = TEMP_VAL_MEM;
        ts->name = name;
        s->nb_globals++;
    }
    return MAKE_TCGV(idx);
}

TCGv tcg_temp_new(TCGType type)
{
    TCGContext *s = &tcg_ctx;
    TCGTemp *ts;
    int idx;

    idx = s->nb_temps;
#if TCG_TARGET_REG_BITS == 32
    if (type == TCG_TYPE_I64) {
        tcg_temp_alloc(s, s->nb_temps + 1);
        ts = &s->temps[s->nb_temps];
        ts->base_type = type;
        ts->type = TCG_TYPE_I32;
        ts->fixed_reg = 0;
        ts->val_type = TEMP_VAL_DEAD;
        ts->mem_allocated = 0;
        ts->name = NULL;
        ts++;
        ts->base_type = TCG_TYPE_I32;
        ts->type = TCG_TYPE_I32;
        ts->val_type = TEMP_VAL_DEAD;
        ts->fixed_reg = 0;
        ts->mem_allocated = 0;
        ts->name = NULL;
        s->nb_temps += 2;
    } else
#endif
    {
        tcg_temp_alloc(s, s->nb_temps + 1);
        ts = &s->temps[s->nb_temps];
        ts->base_type = type;
        ts->type = type;
        ts->fixed_reg = 0;
        ts->val_type = TEMP_VAL_DEAD;
        ts->mem_allocated = 0;
        ts->name = NULL;
        s->nb_temps++;
    }
    return MAKE_TCGV(idx);
}

TCGv tcg_const_i32(int32_t val)
{
    TCGContext *s = &tcg_ctx;
    TCGTemp *ts;
    int idx;

    idx = s->nb_temps;
    tcg_temp_alloc(s, idx + 1);
    ts = &s->temps[idx];
    ts->base_type = ts->type = TCG_TYPE_I32;
    ts->val_type = TEMP_VAL_CONST;
    ts->name = NULL;
    ts->val = val;
    s->nb_temps++;
    return MAKE_TCGV(idx);
}

TCGv tcg_const_i64(int64_t val)
{
    TCGContext *s = &tcg_ctx;
    TCGTemp *ts;