target/openrisc: Tidy handling of delayed branches

Signed-off-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Richard Henderson 2016-04-05 18:00:33 -07:00
parent 24c328521b
commit a01deb36a6
5 changed files with 25 additions and 35 deletions

View File

@ -83,9 +83,6 @@ enum {
/* Version Register */ /* Version Register */
#define SPR_VR 0xFFFF003F #define SPR_VR 0xFFFF003F
/* Internal flags, delay slot flag */
#define D_FLAG 1
/* Interrupt */ /* Interrupt */
#define NR_IRQS 32 #define NR_IRQS 32
@ -298,8 +295,7 @@ typedef struct CPUOpenRISCState {
target_ulong lock_addr; target_ulong lock_addr;
target_ulong lock_value; target_ulong lock_value;
uint32_t flags; /* cpu_flags, we only use it for exception uint32_t dflag; /* In delay slot (boolean) */
in solt so far. */
/* Fields up to this point are cleared by a CPU reset */ /* Fields up to this point are cleared by a CPU reset */
struct {} end_reset_fields; struct {} end_reset_fields;
@ -392,14 +388,16 @@ int cpu_openrisc_get_phys_data(OpenRISCCPU *cpu,
#include "exec/cpu-all.h" #include "exec/cpu-all.h"
#define TB_FLAGS_DFLAG 1
#define TB_FLAGS_OVE SR_OVE
static inline void cpu_get_tb_cpu_state(CPUOpenRISCState *env, static inline void cpu_get_tb_cpu_state(CPUOpenRISCState *env,
target_ulong *pc, target_ulong *pc,
target_ulong *cs_base, uint32_t *flags) target_ulong *cs_base, uint32_t *flags)
{ {
*pc = env->pc; *pc = env->pc;
*cs_base = 0; *cs_base = 0;
/* D_FLAG -- branch instruction exception, OVE overflow trap enable. */ *flags = env->dflag | (env->sr & SR_OVE);
*flags = (env->flags & D_FLAG) | (env->sr & SR_OVE);
} }
static inline int cpu_mmu_index(CPUOpenRISCState *env, bool ifetch) static inline int cpu_mmu_index(CPUOpenRISCState *env, bool ifetch)

View File

@ -73,7 +73,7 @@ int openrisc_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
also clear delayed branch status. */ also clear delayed branch status. */
if (env->pc != tmp) { if (env->pc != tmp) {
env->pc = tmp; env->pc = tmp;
env->flags = 0; env->dflag = 0;
} }
break; break;

View File

@ -34,8 +34,8 @@ void openrisc_cpu_do_interrupt(CPUState *cs)
CPUOpenRISCState *env = &cpu->env; CPUOpenRISCState *env = &cpu->env;
env->epcr = env->pc; env->epcr = env->pc;
if (env->flags & D_FLAG) { if (env->dflag) {
env->flags &= ~D_FLAG; env->dflag = 0;
env->sr |= SR_DSX; env->sr |= SR_DSX;
env->epcr -= 4; env->epcr -= 4;
} else { } else {

View File

@ -45,7 +45,7 @@ void HELPER(mtspr)(CPUOpenRISCState *env,
when "jumping" to the current instruction. */ when "jumping" to the current instruction. */
if (env->pc != rb) { if (env->pc != rb) {
env->pc = rb; env->pc = rb;
env->flags = 0; env->dflag = 0;
cpu_loop_exit(cs); cpu_loop_exit(cs);
} }
break; break;

View File

@ -40,11 +40,11 @@
typedef struct DisasContext { typedef struct DisasContext {
TranslationBlock *tb; TranslationBlock *tb;
target_ulong pc; target_ulong pc;
uint32_t tb_flags, synced_flags, flags;
uint32_t is_jmp; uint32_t is_jmp;
uint32_t mem_idx; uint32_t mem_idx;
int singlestep_enabled; uint32_t tb_flags;
uint32_t delayed_branch; uint32_t delayed_branch;
bool singlestep_enabled;
} DisasContext; } DisasContext;
static TCGv_env cpu_env; static TCGv_env cpu_env;
@ -60,7 +60,7 @@ static TCGv cpu_lock_addr;
static TCGv cpu_lock_value; static TCGv cpu_lock_value;
static TCGv_i32 fpcsr; static TCGv_i32 fpcsr;
static TCGv_i64 cpu_mac; /* MACHI:MACLO */ static TCGv_i64 cpu_mac; /* MACHI:MACLO */
static TCGv_i32 env_flags; static TCGv_i32 cpu_dflag;
#include "exec/gen-icount.h" #include "exec/gen-icount.h"
void openrisc_translate_init(void) void openrisc_translate_init(void)
@ -77,9 +77,9 @@ void openrisc_translate_init(void)
tcg_ctx.tcg_env = cpu_env; tcg_ctx.tcg_env = cpu_env;
cpu_sr = tcg_global_mem_new(cpu_env, cpu_sr = tcg_global_mem_new(cpu_env,
offsetof(CPUOpenRISCState, sr), "sr"); offsetof(CPUOpenRISCState, sr), "sr");
env_flags = tcg_global_mem_new_i32(cpu_env, cpu_dflag = tcg_global_mem_new_i32(cpu_env,
offsetof(CPUOpenRISCState, flags), offsetof(CPUOpenRISCState, dflag),
"flags"); "dflag");
cpu_pc = tcg_global_mem_new(cpu_env, cpu_pc = tcg_global_mem_new(cpu_env,
offsetof(CPUOpenRISCState, pc), "pc"); offsetof(CPUOpenRISCState, pc), "pc");
cpu_ppc = tcg_global_mem_new(cpu_env, cpu_ppc = tcg_global_mem_new(cpu_env,
@ -111,15 +111,6 @@ void openrisc_translate_init(void)
} }
} }
static inline void gen_sync_flags(DisasContext *dc)
{
/* Sync the tb dependent flag between translate and runtime. */
if ((dc->tb_flags ^ dc->synced_flags) & D_FLAG) {
tcg_gen_movi_tl(env_flags, dc->tb_flags & D_FLAG);
dc->synced_flags = dc->tb_flags;
}
}
static void gen_exception(DisasContext *dc, unsigned int excp) static void gen_exception(DisasContext *dc, unsigned int excp)
{ {
TCGv_i32 tmp = tcg_const_i32(excp); TCGv_i32 tmp = tcg_const_i32(excp);
@ -230,8 +221,6 @@ static void gen_jump(DisasContext *dc, int32_t n26, uint32_t reg, uint32_t op0)
} }
dc->delayed_branch = 2; dc->delayed_branch = 2;
dc->tb_flags |= D_FLAG;
gen_sync_flags(dc);
} }
static void gen_ove_cy(DisasContext *dc) static void gen_ove_cy(DisasContext *dc)
@ -1512,10 +1501,9 @@ void gen_intermediate_code(CPUOpenRISCState *env, struct TranslationBlock *tb)
dc->is_jmp = DISAS_NEXT; dc->is_jmp = DISAS_NEXT;
dc->pc = pc_start; dc->pc = pc_start;
dc->flags = cpu->env.cpucfgr;
dc->mem_idx = cpu_mmu_index(&cpu->env, false); dc->mem_idx = cpu_mmu_index(&cpu->env, false);
dc->synced_flags = dc->tb_flags = tb->flags; dc->tb_flags = tb->flags;
dc->delayed_branch = (dc->tb_flags & D_FLAG) != 0; dc->delayed_branch = (dc->tb_flags & TB_FLAGS_DFLAG) != 0;
dc->singlestep_enabled = cs->singlestep_enabled; dc->singlestep_enabled = cs->singlestep_enabled;
next_page_start = (pc_start & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE; next_page_start = (pc_start & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE;
@ -1539,7 +1527,8 @@ void gen_intermediate_code(CPUOpenRISCState *env, struct TranslationBlock *tb)
gen_tb_start(tb); gen_tb_start(tb);
do { do {
tcg_gen_insn_start(dc->pc, num_insns != 0); tcg_gen_insn_start(dc->pc, (dc->delayed_branch ? 1 : 0)
| (num_insns ? 2 : 0));
num_insns++; num_insns++;
if (unlikely(cpu_breakpoint_test(cs, dc->pc, BP_ANY))) { if (unlikely(cpu_breakpoint_test(cs, dc->pc, BP_ANY))) {
@ -1564,8 +1553,6 @@ void gen_intermediate_code(CPUOpenRISCState *env, struct TranslationBlock *tb)
if (dc->delayed_branch) { if (dc->delayed_branch) {
dc->delayed_branch--; dc->delayed_branch--;
if (!dc->delayed_branch) { if (!dc->delayed_branch) {
dc->tb_flags &= ~D_FLAG;
gen_sync_flags(dc);
tcg_gen_mov_tl(cpu_pc, jmp_pc); tcg_gen_mov_tl(cpu_pc, jmp_pc);
tcg_gen_discard_tl(jmp_pc); tcg_gen_discard_tl(jmp_pc);
dc->is_jmp = DISAS_UPDATE; dc->is_jmp = DISAS_UPDATE;
@ -1583,6 +1570,10 @@ void gen_intermediate_code(CPUOpenRISCState *env, struct TranslationBlock *tb)
gen_io_end(); gen_io_end();
} }
if ((dc->tb_flags & TB_FLAGS_DFLAG ? 1 : 0) != (dc->delayed_branch != 0)) {
tcg_gen_movi_i32(cpu_dflag, dc->delayed_branch != 0);
}
tcg_gen_movi_tl(cpu_ppc, dc->pc - 4); tcg_gen_movi_tl(cpu_ppc, dc->pc - 4);
if (dc->is_jmp == DISAS_NEXT) { if (dc->is_jmp == DISAS_NEXT) {
dc->is_jmp = DISAS_UPDATE; dc->is_jmp = DISAS_UPDATE;
@ -1641,7 +1632,8 @@ void restore_state_to_opc(CPUOpenRISCState *env, TranslationBlock *tb,
target_ulong *data) target_ulong *data)
{ {
env->pc = data[0]; env->pc = data[0];
if (data[1]) { env->dflag = data[1] & 1;
if (data[1] & 2) {
env->ppc = env->pc - 4; env->ppc = env->pc - 4;
} }
} }