Incrementally paves the way towards using the generic instruction translation
loop.
Signed-off-by: Lluís Vilanova <vilan...@ac.upc.edu>
---
target/arm/translate.c | 147 +++++++++++++++++++++++++++---------------------
target/arm/translate.h | 4 +
2 files changed, 88 insertions(+), 63 deletions(-)
diff --git a/target/arm/translate.c b/target/arm/translate.c
index 790eaa2164..7ab09a7e5f 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -11841,6 +11841,9 @@ static void
arm_trblock_init_disas_context(DisasContextBase *dcbase,
dc->pstate_ss = ARM_TBFLAG_PSTATE_SS(dc->base.tb->flags);
dc->is_ldex = false;
dc->ss_same_el = false; /* Can't be true since EL_d must be AArch64 */
+
+ dc->next_page_start =
+ (dc->base.pc_first & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE;
}
static void arm_trblock_init_globals(DisasContextBase *dcbase, CPUState *cpu)
@@ -11944,14 +11947,82 @@ static BreakpointCheckType
arm_trblock_breakpoint_check(
}
}
+static target_ulong arm_trblock_translate_insn(DisasContextBase *dcbase,
+ CPUState *cpu)
+{
+ DisasContext *dc = container_of(dcbase, DisasContext, base);
+ CPUARMState *env = cpu->env_ptr;
+
+ if (dc->ss_active && !dc->pstate_ss) {
+ /* Singlestep state is Active-pending.
+ * If we're in this state at the start of a TB then either
+ * a) we just took an exception to an EL which is being debugged
+ * and this is the first insn in the exception handler
+ * b) debug exceptions were masked and we just unmasked them
+ * without changing EL (eg by clearing PSTATE.D)
+ * In either case we're going to take a swstep exception in the
+ * "did not step an insn" case, and so the syndrome ISV and EX
+ * bits should be zero.
+ */
+ assert(dc->base.num_insns == 1);
+ gen_exception(EXCP_UDEF, syn_swstep(dc->ss_same_el, 0, 0),
+ default_exception_el(dc));
+ dc->base.is_jmp = DISAS_SKIP;
+ return dc->pc;
+ }
+
+ if (dc->thumb) {
+ disas_thumb_insn(env, dc);
+ if (dc->condexec_mask) {
+ dc->condexec_cond = (dc->condexec_cond & 0xe)
+ | ((dc->condexec_mask >> 4) & 1);
+ dc->condexec_mask = (dc->condexec_mask << 1) & 0x1f;
+ if (dc->condexec_mask == 0) {
+ dc->condexec_cond = 0;
+ }
+ }
+ } else {
+ unsigned int insn = arm_ldl_code(env, dc->pc, dc->sctlr_b);
+ dc->pc += 4;
+ disas_arm_insn(dc, insn);
+ }
+
+ if (dc->condjmp && !dc->base.is_jmp) {
+ gen_set_label(dc->condlabel);
+ dc->condjmp = 0;
+ }
+
+
+ /* Translation stops when a conditional branch is encountered.
+ * Otherwise the subsequent code could get translated several times.
+ * Also stop translation when a page boundary is reached. This
+ * ensures prefetch aborts occur at the right place. */
+
+ if (is_singlestepping(dc)) {
+ dc->base.is_jmp = DISAS_SS;
+ } else if ((dc->pc >= dc->next_page_start) ||
+ ((dc->pc >= dc->next_page_start - 3) &&
+ insn_crosses_page(env, dc))) {
+ /* We want to stop the TB if the next insn starts in a new page,
+ * or if it spans between this page and the next. This means that
+ * if we're looking at the last halfword in the page we need to
+ * see if it's a 16-bit Thumb insn (which will fit in this TB)
+ * or a 32-bit Thumb insn (which won't).
+ * This is to avoid generating a silly TB with a single 16-bit insn
+ * in it at the end of this page (which would execute correctly
+ * but isn't very efficient).
+ */
+ return DISAS_PAGE_CROSS;
+ }
+
+ return dc->pc;
+}
+
/* generate intermediate code for basic block 'tb'. */
void gen_intermediate_code(CPUState *cpu, TranslationBlock *tb)
{
- CPUARMState *env = cpu->env_ptr;
DisasContext dc1, *dc = &dc1;
- target_ulong next_page_start;
int max_insns;
- bool end_of_page;
/* generate intermediate code */
@@ -11973,7 +12044,6 @@ void gen_intermediate_code(CPUState *cpu,
TranslationBlock *tb)
arm_trblock_init_globals(&dc->base, cpu);
- next_page_start = (dc->base.pc_first & TARGET_PAGE_MASK) +
TARGET_PAGE_SIZE;
max_insns = tb->cflags & CF_COUNT_MASK;
if (max_insns == 0) {
max_insns = CF_COUNT_MASK;
@@ -12024,72 +12094,20 @@ void gen_intermediate_code(CPUState *cpu,
TranslationBlock *tb)
gen_io_start();
}
- if (dc->ss_active && !dc->pstate_ss) {
- /* Singlestep state is Active-pending.
- * If we're in this state at the start of a TB then either
- * a) we just took an exception to an EL which is being debugged
- * and this is the first insn in the exception handler
- * b) debug exceptions were masked and we just unmasked them
- * without changing EL (eg by clearing PSTATE.D)
- * In either case we're going to take a swstep exception in the
- * "did not step an insn" case, and so the syndrome ISV and EX
- * bits should be zero.
- */
- assert(dc->base.num_insns == 1);
- gen_exception(EXCP_UDEF, syn_swstep(dc->ss_same_el, 0, 0),
- default_exception_el(dc));
- goto done_generating;
- }
-
- if (dc->thumb) {
- disas_thumb_insn(env, dc);
- if (dc->condexec_mask) {
- dc->condexec_cond = (dc->condexec_cond & 0xe)
- | ((dc->condexec_mask >> 4) & 1);
- dc->condexec_mask = (dc->condexec_mask << 1) & 0x1f;
- if (dc->condexec_mask == 0) {
- dc->condexec_cond = 0;
- }
- }
- } else {
- unsigned int insn = arm_ldl_code(env, dc->pc, dc->sctlr_b);
- dc->pc += 4;
- disas_arm_insn(dc, insn);
- }
-
- if (dc->condjmp && !dc->base.is_jmp) {
- gen_set_label(dc->condlabel);
- dc->condjmp = 0;
- }
+ dc->base.pc_next = arm_trblock_translate_insn(&dc->base, cpu);
if (tcg_check_temp_count()) {
fprintf(stderr, "TCG temporary leak before "TARGET_FMT_lx"\n",
dc->pc);
}
- /* Translation stops when a conditional branch is encountered.
- * Otherwise the subsequent code could get translated several times.
- * Also stop translation when a page boundary is reached. This
- * ensures prefetch aborts occur at the right place. */
-
- /* We want to stop the TB if the next insn starts in a new page,
- * or if it spans between this page and the next. This means that
- * if we're looking at the last halfword in the page we need to
- * see if it's a 16-bit Thumb insn (which will fit in this TB)
- * or a 32-bit Thumb insn (which won't).
- * This is to avoid generating a silly TB with a single 16-bit insn
- * in it at the end of this page (which would execute correctly
- * but isn't very efficient).
- */
- end_of_page = (dc->pc >= next_page_start) ||
- ((dc->pc >= next_page_start - 3) && insn_crosses_page(env, dc));
-
- } while (!dc->base.is_jmp && !tcg_op_buf_full() &&
- !is_singlestepping(dc) &&
- !singlestep &&
- !end_of_page &&
- dc->base.num_insns < max_insns);
+ if (!dc->base.is_jmp && (tcg_op_buf_full() || singlestep ||
+ dc->base.num_insns >= max_insns)) {
+ dc->base.is_jmp = DISAS_TOO_MANY;
+ }
+ } while (!dc->base.is_jmp);
+ if (dc->base.is_jmp != DISAS_SKIP) {
if (tb->cflags & CF_LAST_IO) {
if (dc->condjmp) {
/* FIXME: This can theoretically happen with self-modifying
@@ -12127,6 +12145,7 @@ void gen_intermediate_code(CPUState *cpu,
TranslationBlock *tb)
gen_exception(EXCP_SMC, syn_aa32_smc(), 3);
break;
case DISAS_NEXT:
+ case DISAS_TOO_MANY:
case DISAS_UPDATE:
gen_set_pc_im(dc, dc->pc);
/* fall through */
@@ -12145,6 +12164,7 @@ void gen_intermediate_code(CPUState *cpu,
TranslationBlock *tb)
*/
switch(dc->base.is_jmp) {
case DISAS_NEXT:
+ case DISAS_TOO_MANY:
gen_goto_tb(dc, 1, dc->pc);
break;
case DISAS_UPDATE:
@@ -12198,6 +12218,7 @@ void gen_intermediate_code(CPUState *cpu,
TranslationBlock *tb)
gen_goto_tb(dc, 1, dc->pc);
}
}
+ }
done_generating:
gen_tb_end(tb, dc->base.num_insns);
diff --git a/target/arm/translate.h b/target/arm/translate.h
index 6fe40a344a..f830775540 100644
--- a/target/arm/translate.h
+++ b/target/arm/translate.h
@@ -9,6 +9,7 @@ typedef struct DisasContext {
DisasContextBase base;
target_ulong pc;
+ target_ulong next_page_start;
uint32_t insn;
/* Nonzero if this instruction has been conditionally skipped. */
int condjmp;
@@ -148,6 +149,9 @@ static void disas_set_insn_syndrome(DisasContext *s,
uint32_t syn)
* as opposed to attempting to use lookup_and_goto_ptr.
*/
#define DISAS_EXIT DISAS_TARGET_11
+#define DISAS_SS DISAS_TARGET_12
+#define DISAS_PAGE_CROSS DISAS_TARGET_13
+#define DISAS_SKIP DISAS_TARGET_14
#ifdef TARGET_AARCH64
void a64_translate_init(void);
