Since jump_pc[1] is always npc + 4, and since we
only continue translation when pc + 4 == npc, we
can infer that jump_pc[1] == pc + 8.
Because of that, we can encode the branch destination
into a single word, and store that in npc.
Signed-off-by: Richard Henderson <r...@twiddle.net>
---
target-sparc/translate.c | 50 +++++++++++++++++++++++-------------------------
1 file changed, 24 insertions(+), 26 deletions(-)
diff --git a/target-sparc/translate.c b/target-sparc/translate.c
index 8aa19e1..b1e533f 100644
--- a/target-sparc/translate.c
+++ b/target-sparc/translate.c
@@ -39,7 +39,7 @@
#define DYNAMIC_PC 1 /* dynamic pc value */
#define JUMP_PC 2 /* dynamic pc value which takes only two values
- according to jump_pc[T2] */
+ according to npc & ~3 and pc + 4. */
/* global register indexes */
static TCGv_ptr cpu_env, cpu_regwptr;
@@ -65,14 +65,12 @@ static TCGv cpu_wim;
static TCGv_i64 cpu_fpr[TARGET_DPREGS];
static target_ulong gen_opc_npc[OPC_BUF_SIZE];
-static target_ulong gen_opc_jump_pc[2];
#include "exec/gen-icount.h"
typedef struct DisasContext {
target_ulong pc; /* current Program Counter: integer or DYNAMIC_PC */
target_ulong npc; /* next PC: integer or DYNAMIC_PC or JUMP_PC */
- target_ulong jump_pc[2]; /* used when JUMP_PC pc value is used */
int is_br;
int mem_idx;
int fpu_enabled;
@@ -976,9 +974,7 @@ static void gen_branch_n(DisasContext *dc, target_ulong pc1)
if (likely(npc != DYNAMIC_PC)) {
dc->pc = npc;
- dc->jump_pc[0] = pc1;
- dc->jump_pc[1] = npc + 4;
- dc->npc = JUMP_PC;
+ dc->npc = pc1 | JUMP_PC;
} else {
TCGv t, z;
@@ -997,12 +993,15 @@ static void gen_branch_n(DisasContext *dc, target_ulong
pc1)
static inline void gen_generic_branch(DisasContext *dc)
{
- TCGv npc0 = tcg_const_tl(dc->jump_pc[0]);
- TCGv npc1 = tcg_const_tl(dc->jump_pc[1]);
- TCGv zero = tcg_const_tl(0);
+ TCGv npc0, npc1, zero;
- tcg_gen_movcond_tl(TCG_COND_NE, cpu_npc, cpu_cond, zero, npc0, npc1);
+ assert((dc->npc & 3) == JUMP_PC);
+ assert((dc->pc & 3) == 0);
+ npc0 = tcg_const_tl(dc->npc & ~3);
+ npc1 = tcg_const_tl(dc->pc + 4);
+ zero = tcg_const_tl(0);
+ tcg_gen_movcond_tl(TCG_COND_NE, cpu_npc, cpu_cond, zero, npc0, npc1);
tcg_temp_free(npc0);
tcg_temp_free(npc1);
tcg_temp_free(zero);
@@ -1012,7 +1011,7 @@ static inline void gen_generic_branch(DisasContext *dc)
have been set for a jump */
static inline void flush_cond(DisasContext *dc)
{
- if (dc->npc == JUMP_PC) {
+ if (dc->npc & JUMP_PC) {
gen_generic_branch(dc);
dc->npc = DYNAMIC_PC;
}
@@ -1020,7 +1019,7 @@ static inline void flush_cond(DisasContext *dc)
static inline void save_npc(DisasContext *dc)
{
- if (dc->npc == JUMP_PC) {
+ if (dc->npc & JUMP_PC) {
gen_generic_branch(dc);
dc->npc = DYNAMIC_PC;
} else if (dc->npc != DYNAMIC_PC) {
@@ -1044,7 +1043,7 @@ static inline void save_state(DisasContext *dc)
static inline void gen_mov_pc_npc(DisasContext *dc)
{
- if (dc->npc == JUMP_PC) {
+ if (dc->npc & JUMP_PC) {
gen_generic_branch(dc);
tcg_gen_mov_tl(cpu_pc, cpu_npc);
dc->pc = DYNAMIC_PC;
@@ -5122,9 +5121,9 @@ static void disas_sparc_insn(DisasContext * dc, unsigned
int insn)
if (dc->npc == DYNAMIC_PC) {
dc->pc = DYNAMIC_PC;
gen_op_next_insn();
- } else if (dc->npc == JUMP_PC) {
- /* we can do a static jump */
- gen_branch2(dc, dc->jump_pc[0], dc->jump_pc[1], cpu_cond);
+ } else if (dc->npc & JUMP_PC) {
+ assert((dc->pc & 3) == 0);
+ gen_branch2(dc, dc->npc & ~3, dc->pc + 4, cpu_cond);
dc->is_br = 1;
} else {
dc->pc = dc->npc;
@@ -5324,8 +5323,6 @@ static inline void
gen_intermediate_code_internal(SPARCCPU *cpu,
#if 0
log_page_dump();
#endif
- gen_opc_jump_pc[0] = dc->jump_pc[0];
- gen_opc_jump_pc[1] = dc->jump_pc[1];
} else {
tb->size = last_pc + 4 - pc_start;
tb->icount = num_insns;
@@ -5453,17 +5450,18 @@ void gen_intermediate_code_init(CPUSPARCState *env)
void restore_state_to_opc(CPUSPARCState *env, TranslationBlock *tb, int pc_pos)
{
- target_ulong npc;
- env->pc = tcg_ctx.gen_opc_pc[pc_pos];
+ target_ulong pc, npc;
+
+ env->pc = pc = tcg_ctx.gen_opc_pc[pc_pos];
npc = gen_opc_npc[pc_pos];
- if (npc == 1) {
- /* dynamic NPC: already stored */
- } else if (npc == 2) {
- /* jump PC: use 'cond' and the jump targets of the translation */
+ if (npc == DYNAMIC_PC) {
+ /* already stored */
+ } else if (npc & JUMP_PC) {
+ /* use 'cond' and the jump targets of the translation */
if (env->cond) {
- env->npc = gen_opc_jump_pc[0];
+ env->npc = npc & ~3;
} else {
- env->npc = gen_opc_jump_pc[1];
+ env->npc = pc + 8;
}
} else {
env->npc = npc;
--
2.4.3
