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authorRichard Henderson <rth@twiddle.net>2016-11-03 14:50:01 -0600
committerLaurent Vivier <laurent@vivier.eu>2016-12-27 18:16:42 +0100
commit8a1e52b69d2cd1c633f3c473a213d575931bf46d (patch)
tree987db2fe9b4b8f21279799b80ce9d3dcbea7aec5 /target/m68k
parente5fdf663cf01f824f0e29701551a2c29554d80a4 (diff)
target-m68k: Delay autoinc writeback
Signed-off-by: Richard Henderson <rth@twiddle.net> Message-Id: <1478206203-4606-2-git-send-email-rth@twiddle.net>
Diffstat (limited to 'target/m68k')
-rw-r--r--target/m68k/translate.c84
1 files changed, 64 insertions, 20 deletions
diff --git a/target/m68k/translate.c b/target/m68k/translate.c
index d6ed883882..a9066dc09f 100644
--- a/target/m68k/translate.c
+++ b/target/m68k/translate.c
@@ -59,12 +59,12 @@ static TCGv cpu_aregs[8];
static TCGv_i64 cpu_fregs[8];
static TCGv_i64 cpu_macc[4];
-#define REG(insn, pos) (((insn) >> (pos)) & 7)
+#define REG(insn, pos) (((insn) >> (pos)) & 7)
#define DREG(insn, pos) cpu_dregs[REG(insn, pos)]
-#define AREG(insn, pos) cpu_aregs[REG(insn, pos)]
+#define AREG(insn, pos) get_areg(s, REG(insn, pos))
#define FREG(insn, pos) cpu_fregs[REG(insn, pos)]
-#define MACREG(acc) cpu_macc[acc]
-#define QREG_SP cpu_aregs[7]
+#define MACREG(acc) cpu_macc[acc]
+#define QREG_SP get_areg(s, 7)
static TCGv NULL_QREG;
#define IS_NULL_QREG(t) (TCGV_EQUAL(t, NULL_QREG))
@@ -141,8 +141,55 @@ typedef struct DisasContext {
int singlestep_enabled;
TCGv_i64 mactmp;
int done_mac;
+ int writeback_mask;
+ TCGv writeback[8];
} DisasContext;
+static TCGv get_areg(DisasContext *s, unsigned regno)
+{
+ if (s->writeback_mask & (1 << regno)) {
+ return s->writeback[regno];
+ } else {
+ return cpu_aregs[regno];
+ }
+}
+
+static void delay_set_areg(DisasContext *s, unsigned regno,
+ TCGv val, bool give_temp)
+{
+ if (s->writeback_mask & (1 << regno)) {
+ if (give_temp) {
+ tcg_temp_free(s->writeback[regno]);
+ s->writeback[regno] = val;
+ } else {
+ tcg_gen_mov_i32(s->writeback[regno], val);
+ }
+ } else {
+ s->writeback_mask |= 1 << regno;
+ if (give_temp) {
+ s->writeback[regno] = val;
+ } else {
+ TCGv tmp = tcg_temp_new();
+ s->writeback[regno] = tmp;
+ tcg_gen_mov_i32(tmp, val);
+ }
+ }
+}
+
+static void do_writebacks(DisasContext *s)
+{
+ unsigned mask = s->writeback_mask;
+ if (mask) {
+ s->writeback_mask = 0;
+ do {
+ unsigned regno = ctz32(mask);
+ tcg_gen_mov_i32(cpu_aregs[regno], s->writeback[regno]);
+ tcg_temp_free(s->writeback[regno]);
+ mask &= mask - 1;
+ } while (mask);
+ }
+}
+
#define DISAS_JUMP_NEXT 4
#if defined(CONFIG_USER_ONLY)
@@ -331,7 +378,7 @@ static inline uint32_t read_im32(CPUM68KState *env, DisasContext *s)
}
/* Calculate and address index. */
-static TCGv gen_addr_index(uint16_t ext, TCGv tmp)
+static TCGv gen_addr_index(DisasContext *s, uint16_t ext, TCGv tmp)
{
TCGv add;
int scale;
@@ -388,7 +435,7 @@ static TCGv gen_lea_indexed(CPUM68KState *env, DisasContext *s, TCGv base)
tmp = tcg_temp_new();
if ((ext & 0x44) == 0) {
/* pre-index */
- add = gen_addr_index(ext, tmp);
+ add = gen_addr_index(s, ext, tmp);
} else {
add = NULL_QREG;
}
@@ -417,7 +464,7 @@ static TCGv gen_lea_indexed(CPUM68KState *env, DisasContext *s, TCGv base)
/* memory indirect */
base = gen_load(s, OS_LONG, add, 0);
if ((ext & 0x44) == 4) {
- add = gen_addr_index(ext, tmp);
+ add = gen_addr_index(s, ext, tmp);
tcg_gen_add_i32(tmp, add, base);
add = tmp;
} else {
@@ -441,7 +488,7 @@ static TCGv gen_lea_indexed(CPUM68KState *env, DisasContext *s, TCGv base)
} else {
/* brief extension word format */
tmp = tcg_temp_new();
- add = gen_addr_index(ext, tmp);
+ add = gen_addr_index(s, ext, tmp);
if (!IS_NULL_QREG(base)) {
tcg_gen_add_i32(tmp, add, base);
if ((int8_t)ext)
@@ -755,10 +802,11 @@ static TCGv gen_ea(CPUM68KState *env, DisasContext *s, uint16_t insn,
case 3: /* Indirect postincrement. */
reg = AREG(insn, 0);
result = gen_ldst(s, opsize, reg, val, what);
- /* ??? This is not exception safe. The instruction may still
- fault after this point. */
- if (what == EA_STORE || !addrp)
- tcg_gen_addi_i32(reg, reg, opsize_bytes(opsize));
+ if (what == EA_STORE || !addrp) {
+ TCGv tmp = tcg_temp_new();
+ tcg_gen_addi_i32(tmp, reg, opsize_bytes(opsize));
+ delay_set_areg(s, REG(insn, 0), tmp, true);
+ }
return result;
case 4: /* Indirect predecrememnt. */
{
@@ -773,11 +821,8 @@ static TCGv gen_ea(CPUM68KState *env, DisasContext *s, uint16_t insn,
*addrp = tmp;
}
result = gen_ldst(s, opsize, tmp, val, what);
- /* ??? This is not exception safe. The instruction may still
- fault after this point. */
if (what == EA_STORE || !addrp) {
- reg = AREG(insn, 0);
- tcg_gen_mov_i32(reg, tmp);
+ delay_set_areg(s, REG(insn, 0), tmp, false);
}
}
return result;
@@ -3446,11 +3491,9 @@ void register_m68k_insns (CPUM68KState *env)
write back the result to memory before setting the condition codes. */
static void disas_m68k_insn(CPUM68KState * env, DisasContext *s)
{
- uint16_t insn;
-
- insn = read_im16(env, s);
-
+ uint16_t insn = read_im16(env, s);
opcode_table[insn](env, s, insn);
+ do_writebacks(s);
}
/* generate intermediate code for basic block 'tb'. */
@@ -3478,6 +3521,7 @@ void gen_intermediate_code(CPUM68KState *env, TranslationBlock *tb)
dc->fpcr = env->fpcr;
dc->user = (env->sr & SR_S) == 0;
dc->done_mac = 0;
+ dc->writeback_mask = 0;
num_insns = 0;
max_insns = tb->cflags & CF_COUNT_MASK;
if (max_insns == 0) {