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authorLaurent Vivier <laurent@vivier.eu>2015-08-09 01:44:24 +0200
committerLaurent Vivier <laurent@vivier.eu>2016-10-25 20:54:47 +0200
commit9fdb533fb129b19610941bd1e5dd93e7471a18f5 (patch)
treeb6d6d84319038c3468e478b0ce1b1e3522e09c39 /target-m68k
parent91f90d7191f862ab27528dbdf76cee55c77f79cf (diff)
downloadqemu-arm-9fdb533fb129b19610941bd1e5dd93e7471a18f5.tar.gz
target-m68k: update CPU flags management
Copied from target-i386 Signed-off-by: Laurent Vivier <laurent@vivier.eu> Reviewed-by: Richard Henderson <rth@twiddle.net>
Diffstat (limited to 'target-m68k')
-rw-r--r--target-m68k/cpu.h5
-rw-r--r--target-m68k/translate.c121
2 files changed, 86 insertions, 40 deletions
diff --git a/target-m68k/cpu.h b/target-m68k/cpu.h
index 72a939eeaa..f0f670c2e2 100644
--- a/target-m68k/cpu.h
+++ b/target-m68k/cpu.h
@@ -167,7 +167,7 @@ int cpu_m68k_signal_handler(int host_signum, void *pinfo,
* using this information. Condition codes are not generated if they
* are only needed for conditional branches.
*/
-enum {
+typedef enum {
CC_OP_DYNAMIC, /* Use env->cc_op */
CC_OP_FLAGS, /* CC_DEST = CVZN, CC_SRC = unused */
CC_OP_LOGICB, /* CC_DEST = result, CC_SRC = unused */
@@ -188,7 +188,8 @@ enum {
CC_OP_SHIFTB, /* CC_DEST = result, CC_SRC = carry */
CC_OP_SHIFTW, /* CC_DEST = result, CC_SRC = carry */
CC_OP_SHIFT, /* CC_DEST = result, CC_SRC = carry */
-};
+ CC_OP_NB,
+} CCOp;
#define CCF_C 0x01
#define CCF_V 0x02
diff --git a/target-m68k/translate.c b/target-m68k/translate.c
index 3db7918b98..edd8744d20 100644
--- a/target-m68k/translate.c
+++ b/target-m68k/translate.c
@@ -133,7 +133,7 @@ typedef struct DisasContext {
target_ulong insn_pc; /* Start of the current instruction. */
target_ulong pc;
int is_jmp;
- int cc_op;
+ CCOp cc_op; /* Current CC operation */
int user;
uint32_t fpcr;
struct TranslationBlock *tb;
@@ -175,6 +175,53 @@ typedef void (*disas_proc)(CPUM68KState *env, DisasContext *s, uint16_t insn);
uint16_t insn)
#endif
+enum {
+ USES_CC_DST = 1,
+ USES_CC_SRC = 2,
+};
+
+static const uint8_t cc_op_live[CC_OP_NB] = {
+ [CC_OP_DYNAMIC] = USES_CC_DST | USES_CC_SRC,
+ [CC_OP_FLAGS] = USES_CC_DST,
+ [CC_OP_LOGICB ... CC_OP_LOGIC] = USES_CC_DST,
+ [CC_OP_ADDB ... CC_OP_ADD] = USES_CC_DST | USES_CC_SRC,
+ [CC_OP_SUBB ... CC_OP_SUB] = USES_CC_DST | USES_CC_SRC,
+ [CC_OP_ADDXB ... CC_OP_ADDX] = USES_CC_DST | USES_CC_SRC,
+ [CC_OP_SUBXB ... CC_OP_SUBX] = USES_CC_DST | USES_CC_SRC,
+ [CC_OP_SHIFTB ... CC_OP_SHIFT] = USES_CC_DST | USES_CC_SRC,
+};
+
+static void set_cc_op(DisasContext *s, CCOp op)
+{
+ int dead;
+
+ if (s->cc_op == op) {
+ return;
+ }
+
+ /* Discard CC computation that will no longer be used. */
+
+ dead = cc_op_live[s->cc_op] & ~cc_op_live[op];
+ if (dead & USES_CC_DST) {
+ tcg_gen_discard_i32(QREG_CC_DEST);
+ }
+ if (dead & USES_CC_SRC) {
+ tcg_gen_discard_i32(QREG_CC_SRC);
+ }
+ if (s->cc_op == CC_OP_DYNAMIC) {
+ tcg_gen_discard_i32(QREG_CC_OP);
+ }
+ s->cc_op = op;
+}
+
+/* Update the CPU env CC_OP state. */
+static inline void update_cc_op(DisasContext *s)
+{
+ if (s->cc_op != CC_OP_DYNAMIC) {
+ tcg_gen_movi_i32(QREG_CC_OP, s->cc_op);
+ }
+}
+
/* Generate a load from the specified address. Narrow values are
sign extended to full register width. */
static inline TCGv gen_load(DisasContext * s, int opsize, TCGv addr, int sign)
@@ -411,31 +458,28 @@ static TCGv gen_lea_indexed(CPUM68KState *env, DisasContext *s, TCGv base)
return add;
}
-/* Update the CPU env CC_OP state. */
-static inline void gen_flush_cc_op(DisasContext *s)
-{
- if (s->cc_op != CC_OP_DYNAMIC)
- tcg_gen_movi_i32(QREG_CC_OP, s->cc_op);
-}
-
/* Evaluate all the CC flags. */
+
static inline void gen_flush_flags(DisasContext *s)
{
if (s->cc_op == CC_OP_FLAGS)
return;
- gen_flush_cc_op(s);
- gen_helper_flush_flags(QREG_CC_DEST, cpu_env, QREG_CC_OP);
- s->cc_op = CC_OP_FLAGS;
+ if (s->cc_op == CC_OP_DYNAMIC) {
+ gen_helper_flush_flags(QREG_CC_DEST, cpu_env, QREG_CC_OP);
+ } else {
+ gen_helper_flush_flags(QREG_CC_DEST, cpu_env, tcg_const_i32(s->cc_op));
+ }
+ set_cc_op(s, CC_OP_FLAGS);
}
#define SET_CC_OP(opsize, op) do { \
switch (opsize) { \
case OS_BYTE: \
- s->cc_op = CC_OP_##op##B; break; \
+ set_cc_op(s, CC_OP_##op##B); break; \
case OS_WORD: \
- s->cc_op = CC_OP_##op##W; break; \
+ set_cc_op(s, CC_OP_##op##W); break; \
case OS_LONG: \
- s->cc_op = CC_OP_##op; break; \
+ set_cc_op(s, CC_OP_##op); break; \
default: \
abort(); \
} \
@@ -719,7 +763,7 @@ static void gen_jmpcc(DisasContext *s, int cond, TCGLabel *l1)
/* TODO: Optimize compare/branch pairs rather than always flushing
flag state to CC_OP_FLAGS. */
gen_flush_flags(s);
- gen_flush_cc_op(s);
+ update_cc_op(s);
switch (cond) {
case 0: /* T */
tcg_gen_br(l1);
@@ -836,7 +880,7 @@ DISAS_INSN(scc)
/* Force a TB lookup after an instruction that changes the CPU state. */
static void gen_lookup_tb(DisasContext *s)
{
- gen_flush_cc_op(s);
+ update_cc_op(s);
tcg_gen_movi_i32(QREG_PC, s->pc);
s->is_jmp = DISAS_UPDATE;
}
@@ -844,7 +888,7 @@ static void gen_lookup_tb(DisasContext *s)
/* Generate a jump to an immediate address. */
static void gen_jmp_im(DisasContext *s, uint32_t dest)
{
- gen_flush_cc_op(s);
+ update_cc_op(s);
tcg_gen_movi_i32(QREG_PC, dest);
s->is_jmp = DISAS_JUMP;
}
@@ -852,14 +896,14 @@ static void gen_jmp_im(DisasContext *s, uint32_t dest)
/* Generate a jump to the address in qreg DEST. */
static void gen_jmp(DisasContext *s, TCGv dest)
{
- gen_flush_cc_op(s);
+ update_cc_op(s);
tcg_gen_mov_i32(QREG_PC, dest);
s->is_jmp = DISAS_JUMP;
}
static void gen_exception(DisasContext *s, uint32_t where, int nr)
{
- gen_flush_cc_op(s);
+ update_cc_op(s);
gen_jmp_im(s, where);
gen_helper_raise_exception(cpu_env, tcg_const_i32(nr));
}
@@ -977,7 +1021,7 @@ DISAS_INSN(divw)
tcg_gen_ext16u_i32(tmp, QREG_DIV1);
tcg_gen_shli_i32(src, QREG_DIV2, 16);
tcg_gen_or_i32(reg, tmp, src);
- s->cc_op = CC_OP_FLAGS;
+ set_cc_op(s, CC_OP_FLAGS);
}
DISAS_INSN(divl)
@@ -1009,7 +1053,7 @@ DISAS_INSN(divl)
/* rem */
tcg_gen_mov_i32 (reg, QREG_DIV2);
}
- s->cc_op = CC_OP_FLAGS;
+ set_cc_op(s, CC_OP_FLAGS);
}
DISAS_INSN(addsub)
@@ -1034,11 +1078,11 @@ DISAS_INSN(addsub)
if (add) {
tcg_gen_add_i32(dest, tmp, src);
tcg_gen_setcond_i32(TCG_COND_LTU, QREG_CC_X, dest, src);
- s->cc_op = CC_OP_ADD;
+ set_cc_op(s, CC_OP_ADD);
} else {
tcg_gen_setcond_i32(TCG_COND_LTU, QREG_CC_X, tmp, src);
tcg_gen_sub_i32(dest, tmp, src);
- s->cc_op = CC_OP_SUB;
+ set_cc_op(s, CC_OP_SUB);
}
gen_update_cc_add(dest, src);
if (insn & 0x100) {
@@ -1225,7 +1269,6 @@ DISAS_INSN(bitop_im)
DEST_EA(env, insn, opsize, tmp, &addr);
}
}
-
DISAS_INSN(arith_im)
{
int op;
@@ -1252,14 +1295,14 @@ DISAS_INSN(arith_im)
tcg_gen_setcond_i32(TCG_COND_LTU, QREG_CC_X, dest, tcg_const_i32(im));
tcg_gen_subi_i32(dest, dest, im);
gen_update_cc_add(dest, tcg_const_i32(im));
- s->cc_op = CC_OP_SUB;
+ set_cc_op(s, CC_OP_SUB);
break;
case 3: /* addi */
tcg_gen_mov_i32(dest, src1);
tcg_gen_addi_i32(dest, dest, im);
gen_update_cc_add(dest, tcg_const_i32(im));
tcg_gen_setcond_i32(TCG_COND_LTU, QREG_CC_X, dest, tcg_const_i32(im));
- s->cc_op = CC_OP_ADD;
+ set_cc_op(s, CC_OP_ADD);
break;
case 5: /* eori */
tcg_gen_xori_i32(dest, src1, im);
@@ -1269,7 +1312,7 @@ DISAS_INSN(arith_im)
tcg_gen_mov_i32(dest, src1);
tcg_gen_subi_i32(dest, dest, im);
gen_update_cc_add(dest, tcg_const_i32(im));
- s->cc_op = CC_OP_SUB;
+ set_cc_op(s, CC_OP_SUB);
break;
default:
abort();
@@ -1384,10 +1427,9 @@ DISAS_INSN(neg)
src1 = tcg_temp_new();
tcg_gen_mov_i32(src1, reg);
tcg_gen_neg_i32(reg, src1);
- s->cc_op = CC_OP_SUB;
gen_update_cc_add(reg, src1);
tcg_gen_setcond_i32(TCG_COND_LTU, QREG_CC_X, tcg_const_i32(0), src1);
- s->cc_op = CC_OP_SUB;
+ set_cc_op(s, CC_OP_SUB);
}
static void gen_set_sr_im(DisasContext *s, uint16_t val, int ccr_only)
@@ -1397,6 +1439,7 @@ static void gen_set_sr_im(DisasContext *s, uint16_t val, int ccr_only)
if (!ccr_only) {
gen_helper_set_sr(cpu_env, tcg_const_i32(val & 0xff00));
}
+ set_cc_op(s, CC_OP_FLAGS);
}
static void gen_set_sr(DisasContext *s, TCGv val, int ccr_only)
@@ -1628,11 +1671,11 @@ DISAS_INSN(addsubq)
if (insn & 0x0100) {
tcg_gen_setcond_i32(TCG_COND_LTU, QREG_CC_X, dest, src2);
tcg_gen_subi_i32(dest, dest, val);
- s->cc_op = CC_OP_SUB;
+ set_cc_op(s, CC_OP_SUB);
} else {
tcg_gen_addi_i32(dest, dest, val);
tcg_gen_setcond_i32(TCG_COND_LTU, QREG_CC_X, dest, src2);
- s->cc_op = CC_OP_ADD;
+ set_cc_op(s, CC_OP_ADD);
}
gen_update_cc_add(dest, src2);
}
@@ -1678,11 +1721,14 @@ DISAS_INSN(branch)
/* Bcc */
l1 = gen_new_label();
gen_jmpcc(s, ((insn >> 8) & 0xf) ^ 1, l1);
+ update_cc_op(s);
gen_jmp_tb(s, 1, base + offset);
gen_set_label(l1);
+ update_cc_op(s);
gen_jmp_tb(s, 0, s->pc);
} else {
/* Unconditional branch. */
+ update_cc_op(s);
gen_jmp_tb(s, 0, base + offset);
}
}
@@ -1858,7 +1904,6 @@ DISAS_INSN(addx)
reg = DREG(insn, 9);
src = DREG(insn, 0);
gen_helper_addx_cc(reg, cpu_env, reg, src);
- s->cc_op = CC_OP_FLAGS;
}
/* TODO: This could be implemented without helper functions. */
@@ -1883,7 +1928,7 @@ DISAS_INSN(shift_im)
gen_helper_sar_cc(reg, cpu_env, reg, shift);
}
}
- s->cc_op = CC_OP_SHIFT;
+ set_cc_op(s, CC_OP_SHIFT);
}
DISAS_INSN(shift_reg)
@@ -1904,7 +1949,7 @@ DISAS_INSN(shift_reg)
gen_helper_sar_cc(reg, cpu_env, reg, shift);
}
}
- s->cc_op = CC_OP_SHIFT;
+ set_cc_op(s, CC_OP_SHIFT);
}
DISAS_INSN(ff1)
@@ -2716,7 +2761,7 @@ DISAS_INSN(macsr_to_ccr)
{
tcg_gen_movi_i32(QREG_CC_X, 0);
tcg_gen_andi_i32(QREG_CC_DEST, QREG_MACSR, 0xf);
- s->cc_op = CC_OP_FLAGS;
+ set_cc_op(s, CC_OP_FLAGS);
}
DISAS_INSN(to_mac)
@@ -3047,20 +3092,20 @@ void gen_intermediate_code(CPUM68KState *env, TranslationBlock *tb)
if (unlikely(cs->singlestep_enabled)) {
/* Make sure the pc is updated, and raise a debug exception. */
if (!dc->is_jmp) {
- gen_flush_cc_op(dc);
+ update_cc_op(dc);
tcg_gen_movi_i32(QREG_PC, dc->pc);
}
gen_helper_raise_exception(cpu_env, tcg_const_i32(EXCP_DEBUG));
} else {
switch(dc->is_jmp) {
case DISAS_NEXT:
- gen_flush_cc_op(dc);
+ update_cc_op(dc);
gen_jmp_tb(dc, 0, dc->pc);
break;
default:
case DISAS_JUMP:
case DISAS_UPDATE:
- gen_flush_cc_op(dc);
+ update_cc_op(dc);
/* indicate that the hash table must be used to find the next TB */
tcg_gen_exit_tb(0);
break;