From ab21785d3f5deffbe0bd90f6370a7d2aac6d438b Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Sun, 4 Mar 2018 20:38:19 -0500 Subject: [PATCH] target/arm: Split out thumb_tr_translate_insn We need not check for ARM vs Thumb state in order to dispatch disassembly of every instruction. Backports commit 722ef0a562a8cd810297b00516e36380e2f33353 from qemu --- qemu/target/arm/translate.c | 124 ++++++++++++++++++++++++------------ 1 file changed, 82 insertions(+), 42 deletions(-) diff --git a/qemu/target/arm/translate.c b/qemu/target/arm/translate.c index 8601af99..19246549 100644 --- a/qemu/target/arm/translate.c +++ b/qemu/target/arm/translate.c @@ -12195,12 +12195,8 @@ static bool arm_tr_breakpoint_check(DisasContextBase *dcbase, CPUState *cpu, return true; } -static void arm_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu) +static bool arm_pre_translate_insn(DisasContext *dc) { - DisasContext *dc = container_of(dcbase, DisasContext, base); - CPUARMState *env = cpu->env_ptr; - TCGContext *tcg_ctx = cpu->uc->tcg_ctx; - #ifdef CONFIG_USER_ONLY /* Intercept jump to the magic kernel page. */ if (dc->pc >= 0xffff0000) { @@ -12208,7 +12204,7 @@ static void arm_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu) conditional execution block. */ gen_exception_internal(dc, EXCP_KERNEL_TRAP); dc->base.is_jmp = DISAS_NORETURN; - return; + return true; } #endif @@ -12227,56 +12223,87 @@ static void arm_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu) gen_exception(dc, EXCP_UDEF, syn_swstep(dc->ss_same_el, 0, 0), default_exception_el(dc)); dc->base.is_jmp = DISAS_NORETURN; - return; + return true; } - 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); - } + return false; +} + +static void arm_post_translate_insn(CPUARMState *env, DisasContext *dc) +{ + TCGContext *tcg_ctx = dc->uc->tcg_ctx; if (dc->condjmp && !dc->base.is_jmp) { gen_set_label(tcg_ctx, dc->condlabel); dc->condjmp = 0; } - if (dc->base.is_jmp == DISAS_NEXT) { - /* 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 (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). - */ - dc->base.is_jmp = DISAS_TOO_MANY; - } + /* 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). + */ + if (dc->base.is_jmp == DISAS_NEXT + && (dc->pc >= dc->next_page_start + || (dc->pc >= dc->next_page_start - 3 + && insn_crosses_page(env, dc)))) { + dc->base.is_jmp = DISAS_TOO_MANY; } dc->base.pc_next = dc->pc; translator_loop_temp_check(&dc->base); } +static void arm_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu) +{ + DisasContext *dc = container_of(dcbase, DisasContext, base); + CPUARMState *env = cpu->env_ptr; + unsigned int insn; + + if (arm_pre_translate_insn(dc)) { + return; + } + + insn = arm_ldl_code(env, dc->pc, dc->sctlr_b); + dc->pc += 4; + disas_arm_insn(dc, insn); + + arm_post_translate_insn(env, dc); +} + +static void thumb_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu) +{ + DisasContext *dc = container_of(dcbase, DisasContext, base); + CPUARMState *env = cpu->env_ptr; + + if (arm_pre_translate_insn(dc)) { + return; + } + + disas_thumb_insn(env, dc); + + /* Advance the Thumb condexec condition. */ + 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; + } + } + + arm_post_translate_insn(env, dc); +} + static void arm_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu) { DisasContext *dc = container_of(dcbase, DisasContext, base); @@ -12416,12 +12443,25 @@ static const TranslatorOps arm_translator_ops = { arm_tr_disas_log, }; +static const TranslatorOps thumb_translator_ops = { + arm_tr_init_disas_context, + arm_tr_tb_start, + arm_tr_insn_start, + arm_tr_breakpoint_check, + thumb_tr_translate_insn, + arm_tr_tb_stop, + arm_tr_disas_log, +}; + /* generate intermediate code for basic block 'tb'. */ void gen_intermediate_code(CPUState *cpu, TranslationBlock *tb) { DisasContext dc; const TranslatorOps *ops = &arm_translator_ops; + if (ARM_TBFLAG_THUMB(tb->flags)) { + ops = &thumb_translator_ops; + } #ifdef TARGET_AARCH64 if (ARM_TBFLAG_AARCH64_STATE(tb->flags)) { ops = &aarch64_translator_ops;