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M68k extended addressing modes.

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git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@2870 c046a42c-6fe2-441c-8c8c-71466251a162
This commit is contained in:
pbrook 2007-05-26 21:16:48 +00:00
parent 5aca8c3b2f
commit e6dbd3b3f0
2 changed files with 125 additions and 33 deletions
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3
target-m68k/cpu.h
View File

@ -160,7 +160,8 @@ enum m68k_features {
M68K_FEATURE_CF_FPU,
M68K_FEATURE_CF_MAC,
M68K_FEATURE_CF_EMAC,
M68K_FEATURE_EXT_FULL /* 68020+ full extension word. */
M68K_FEATURE_EXT_FULL, /* 68020+ full extension word. */
M68K_FEATURE_WORD_INDEX /* word sized address index registers. */
};
static inline int m68k_feature(CPUM68KState *env, int feature)

155
target-m68k/translate.c
View File

@ -42,6 +42,7 @@ static inline void qemu_assert(int cond, const char *msg)
/* internal defines */
typedef struct DisasContext {
CPUM68KState *env;
target_ulong pc;
int is_jmp;
int cc_op;
@ -198,38 +199,6 @@ static int gen_ldst(DisasContext *s, int opsize, int addr, int val)
}
}
/* Handle a base + index + displacement effective addresss. A base of
-1 means pc-relative. */
static int gen_lea_indexed(DisasContext *s, int opsize, int base)
{
int scale;
uint32_t offset;
uint16_t ext;
int add;
int tmp;
offset = s->pc;
ext = lduw_code(s->pc);
s->pc += 2;
tmp = ((ext >> 12) & 7) + ((ext & 0x8000) ? QREG_A0 : QREG_D0);
/* ??? Check W/L bit. */
scale = (ext >> 9) & 3;
if (scale == 0) {
add = tmp;
} else {
add = gen_new_qreg(QMODE_I32);
gen_op_shl32(add, tmp, gen_im32(scale));
}
tmp = gen_new_qreg(QMODE_I32);
if (base != -1) {
gen_op_add32(tmp, base, gen_im32((int8_t)ext));
gen_op_add32(tmp, tmp, add);
} else {
gen_op_add32(tmp, add, gen_im32(offset + (int8_t)ext));
}
return tmp;
}
/* Read a 32-bit immediate constant. */
static inline uint32_t read_im32(DisasContext *s)
{
@ -241,6 +210,127 @@ static inline uint32_t read_im32(DisasContext *s)
return im;
}
/* Calculate and address index. */
static int gen_addr_index(uint16_t ext, int tmp)
{
int add;
int scale;
add = (ext & 0x8000) ? AREG(ext, 12) : DREG(ext, 12);
if ((ext & 0x800) == 0) {
gen_op_ext16s32(tmp, add);
add = tmp;
}
scale = (ext >> 9) & 3;
if (scale != 0) {
gen_op_shl32(tmp, add, gen_im32(scale));
add = tmp;
}
return add;
}
/* Handle a base + index + displacement effective addresss. A base of
-1 means pc-relative. */
static int gen_lea_indexed(DisasContext *s, int opsize, int base)
{
uint32_t offset;
uint16_t ext;
int add;
int tmp;
uint32_t bd, od;
offset = s->pc;
ext = lduw_code(s->pc);
s->pc += 2;
if ((ext & 0x800) == 0 && !m68k_feature(s->env, M68K_FEATURE_WORD_INDEX))
return -1;
if (ext & 0x100) {
/* full extension word format */
if (!m68k_feature(s->env, M68K_FEATURE_EXT_FULL))
return -1;
if ((ext & 0x30) > 0x10) {
/* base displacement */
if ((ext & 0x30) == 0x20) {
bd = (int16_t)lduw_code(s->pc);
s->pc += 2;
} else {
bd = read_im32(s);
}
} else {
bd = 0;
}
tmp = gen_new_qreg(QMODE_I32);
if ((ext & 0x44) == 0) {
/* pre-index */
add = gen_addr_index(ext, tmp);
} else {
add = QREG_NULL;
}
if ((ext & 0x80) == 0) {
/* base not suppressed */
if (base == -1) {
base = gen_im32(offset + bd);
bd = 0;
}
if (add) {
gen_op_add32(tmp, add, base);
add = tmp;
} else {
add = base;
}
}
if (add) {
if (bd != 0) {
gen_op_add32(tmp, add, gen_im32(bd));
add = tmp;
}
} else {
add = gen_im32(bd);
}
if ((ext & 3) != 0) {
/* memory indirect */
base = gen_load(s, OS_LONG, add, 0);
if ((ext & 0x44) == 4) {
add = gen_addr_index(ext, tmp);
gen_op_add32(tmp, add, base);
add = tmp;
} else {
add = base;
}
if ((ext & 3) > 1) {
/* outer displacement */
if ((ext & 3) == 2) {
od = (int16_t)lduw_code(s->pc);
s->pc += 2;
} else {
od = read_im32(s);
}
} else {
od = 0;
}
if (od != 0) {
gen_op_add32(add, tmp, gen_im32(od));
add = tmp;
}
}
} else {
/* brief extension word format */
tmp = gen_new_qreg(QMODE_I32);
add = gen_addr_index(ext, tmp);
if (base != -1) {
gen_op_add32(tmp, add, base);
if ((int8_t)ext)
gen_op_add32(tmp, tmp, gen_im32((int8_t)ext));
} else {
gen_op_add32(tmp, add, gen_im32(offset + (int8_t)ext));
}
add = tmp;
}
return add;
}
/* Update the CPU env CC_OP state. */
static inline void gen_flush_cc_op(DisasContext *s)
@ -2721,6 +2811,7 @@ gen_intermediate_code_internal(CPUState *env, TranslationBlock *tb,
gen_opc_end = gen_opc_buf + OPC_MAX_SIZE;
gen_opparam_ptr = gen_opparam_buf;
dc->env = env;
dc->is_jmp = DISAS_NEXT;
dc->pc = pc_start;
dc->cc_op = CC_OP_DYNAMIC;