Re: [Qemu-devel] [PATCH v3 11/16] tcg-aarch64: Define TCG_TARGET_INSN_UNIT_SIZE

[Claudio Fontana]

On 28.04.2014 21:28, Richard Henderson wrote:
> And use tcg pointer differencing functions as appropriate.
> 
> Cc: Claudio Fontana <address@hidden>
> Signed-off-by: Richard Henderson <address@hidden>
> ---
>  tcg/aarch64/tcg-target.c | 121 
> ++++++++++++++++++++---------------------------
>  tcg/aarch64/tcg-target.h |   1 +
>  2 files changed, 53 insertions(+), 69 deletions(-)
> 
> diff --git a/tcg/aarch64/tcg-target.c b/tcg/aarch64/tcg-target.c
> index 0a580b6..1a71df1 100644
> --- a/tcg/aarch64/tcg-target.c
> +++ b/tcg/aarch64/tcg-target.c
> @@ -63,40 +63,34 @@ static const int tcg_target_call_oarg_regs[1] = {
>  # endif
>  #endif
>  
> -static inline void reloc_pc26(void *code_ptr, intptr_t target)
> +static inline void reloc_pc26(tcg_insn_unit *code_ptr, tcg_insn_unit *target)
>  {
> -    intptr_t offset = (target - (intptr_t)code_ptr) / 4;
> +    ptrdiff_t offset = target - code_ptr;
> +    assert(offset == sextract64(offset, 0, 26));
>      /* read instruction, mask away previous PC_REL26 parameter contents,
>         set the proper offset, then write back the instruction. */
> -    uint32_t insn = *(uint32_t *)code_ptr;
> -    insn = deposit32(insn, 0, 26, offset);
> -    *(uint32_t *)code_ptr = insn;
> +    *code_ptr = deposit32(*code_ptr, 0, 26, offset);
>  }
>  
> -static inline void reloc_pc19(void *code_ptr, intptr_t target)
> +static inline void reloc_pc19(tcg_insn_unit *code_ptr, tcg_insn_unit *target)
>  {
> -    intptr_t offset = (target - (intptr_t)code_ptr) / 4;
> -    /* read instruction, mask away previous PC_REL19 parameter contents,
> -       set the proper offset, then write back the instruction. */
> -    uint32_t insn = *(uint32_t *)code_ptr;
> -    insn = deposit32(insn, 5, 19, offset);
> -    *(uint32_t *)code_ptr = insn;
> +    ptrdiff_t offset = target - code_ptr;
> +    assert(offset == sextract64(offset, 0, 19));
> +    *code_ptr = deposit32(*code_ptr, 5, 19, offset);
>  }
>  
> -static inline void patch_reloc(uint8_t *code_ptr, int type,
> +static inline void patch_reloc(tcg_insn_unit *code_ptr, int type,
>                                 intptr_t value, intptr_t addend)
>  {
> -    value += addend;
> -
> +    assert(addend == 0);
>      switch (type) {
>      case R_AARCH64_JUMP26:
>      case R_AARCH64_CALL26:
> -        reloc_pc26(code_ptr, value);
> +        reloc_pc26(code_ptr, (tcg_insn_unit *)value);
>          break;
>      case R_AARCH64_CONDBR19:
> -        reloc_pc19(code_ptr, value);
> +        reloc_pc19(code_ptr, (tcg_insn_unit *)value);
>          break;
> -
>      default:
>          tcg_abort();
>      }
> @@ -794,15 +788,10 @@ static void tcg_out_cmp(TCGContext *s, TCGType ext, 
> TCGReg a,
>      }
>  }
>  
> -static inline void tcg_out_goto(TCGContext *s, intptr_t target)
> +static inline void tcg_out_goto(TCGContext *s, tcg_insn_unit *target)
>  {
> -    intptr_t offset = (target - (intptr_t)s->code_ptr) / 4;
> -
> -    if (offset < -0x02000000 || offset >= 0x02000000) {
> -        /* out of 26bit range */
> -        tcg_abort();
> -    }
> -
> +    ptrdiff_t offset = target - s->code_ptr;
> +    assert(offset == sextract64(offset, 0, 26));
>      tcg_out_insn(s, 3206, B, offset);
>  }
>  
> @@ -828,29 +817,23 @@ static inline void tcg_out_callr(TCGContext *s, TCGReg 
> reg)
>      tcg_out_insn(s, 3207, BLR, reg);
>  }
>  
> -static inline void tcg_out_call(TCGContext *s, intptr_t target)
> +static inline void tcg_out_call(TCGContext *s, tcg_insn_unit *target)
>  {
> -    intptr_t offset = (target - (intptr_t)s->code_ptr) / 4;
> -
> -    if (offset < -0x02000000 || offset >= 0x02000000) { /* out of 26bit rng 
> */
> -        tcg_out_movi(s, TCG_TYPE_I64, TCG_REG_TMP, target);
> -        tcg_out_callr(s, TCG_REG_TMP);
> -    } else {
> +    ptrdiff_t offset = target - s->code_ptr;
> +    if (offset == sextract64(offset, 0, 26)) {
>          tcg_out_insn(s, 3206, BL, offset);
> +    } else {
> +        tcg_out_movi(s, TCG_TYPE_I64, TCG_REG_TMP, (intptr_t)target);
> +        tcg_out_callr(s, TCG_REG_TMP);
>      }
>  }
>  
>  void aarch64_tb_set_jmp_target(uintptr_t jmp_addr, uintptr_t addr)
>  {
> -    intptr_t target = addr;
> -    intptr_t offset = (target - (intptr_t)jmp_addr) / 4;
> -
> -    if (offset < -0x02000000 || offset >= 0x02000000) {
> -        /* out of 26bit range */
> -        tcg_abort();
> -    }
> +    tcg_insn_unit *code_ptr = (tcg_insn_unit *)jmp_addr;
> +    tcg_insn_unit *target = (tcg_insn_unit *)addr;
>  
> -    patch_reloc((uint8_t *)jmp_addr, R_AARCH64_JUMP26, target, 0);
> +    reloc_pc26(code_ptr, target);
>      flush_icache_range(jmp_addr, jmp_addr + 4);
>  }
>  
> @@ -862,7 +845,7 @@ static inline void tcg_out_goto_label(TCGContext *s, int 
> label_index)
>          tcg_out_reloc(s, s->code_ptr, R_AARCH64_JUMP26, label_index, 0);
>          tcg_out_goto_noaddr(s);
>      } else {
> -        tcg_out_goto(s, l->u.value);
> +        tcg_out_goto(s, l->u.value_ptr);
>      }
>  }
>  
> @@ -884,9 +867,8 @@ static void tcg_out_brcond(TCGContext *s, TCGMemOp ext, 
> TCGCond c, TCGArg a,
>          tcg_out_reloc(s, s->code_ptr, R_AARCH64_CONDBR19, label, 0);
>          offset = tcg_in32(s) >> 5;
>      } else {
> -        offset = l->u.value - (uintptr_t)s->code_ptr;
> -        offset >>= 2;
> -        assert(offset >= -0x40000 && offset < 0x40000);
> +        offset = l->u.value_ptr - s->code_ptr;
> +        assert(offset == sextract64(offset, 0, 19));
>      }
>  
>      if (need_cmp) {
> @@ -982,7 +964,7 @@ static inline void tcg_out_addsub2(TCGContext *s, int 
> ext, TCGReg rl,
>  /* helper signature: helper_ret_ld_mmu(CPUState *env, target_ulong addr,
>   *                                     int mmu_idx, uintptr_t ra)
>   */
> -static const void * const qemu_ld_helpers[16] = {
> +static void * const qemu_ld_helpers[16] = {
>      [MO_UB]   = helper_ret_ldub_mmu,
>      [MO_LEUW] = helper_le_lduw_mmu,
>      [MO_LEUL] = helper_le_ldul_mmu,
> @@ -995,7 +977,7 @@ static const void * const qemu_ld_helpers[16] = {
>  /* helper signature: helper_ret_st_mmu(CPUState *env, target_ulong addr,
>   *                                     uintxx_t val, int mmu_idx, uintptr_t 
> ra)
>   */
> -static const void * const qemu_st_helpers[16] = {
> +static void * const qemu_st_helpers[16] = {
>      [MO_UB]   = helper_ret_stb_mmu,
>      [MO_LEUW] = helper_le_stw_mmu,
>      [MO_LEUL] = helper_le_stl_mmu,
> @@ -1005,11 +987,11 @@ static const void * const qemu_st_helpers[16] = {
>      [MO_BEQ]  = helper_be_stq_mmu,
>  };
>  
> -static inline void tcg_out_adr(TCGContext *s, TCGReg rd, uintptr_t addr)
> +static inline void tcg_out_adr(TCGContext *s, TCGReg rd, void *target)
>  {
> -    addr -= (uintptr_t)s->code_ptr;
> -    assert(addr == sextract64(addr, 0, 21));
> -    tcg_out_insn(s, 3406, ADR, rd, addr);
> +    ptrdiff_t offset = tcg_pcrel_diff(s, target);
> +    assert(offset == sextract64(offset, 0, 21));
> +    tcg_out_insn(s, 3406, ADR, rd, offset);
>  }
>  
>  static void tcg_out_qemu_ld_slow_path(TCGContext *s, TCGLabelQemuLdst *lb)
> @@ -1017,20 +999,20 @@ static void tcg_out_qemu_ld_slow_path(TCGContext *s, 
> TCGLabelQemuLdst *lb)
>      TCGMemOp opc = lb->opc;
>      TCGMemOp size = opc & MO_SIZE;
>  
> -    reloc_pc19(lb->label_ptr[0], (intptr_t)s->code_ptr);
> +    reloc_pc19(lb->label_ptr[0], s->code_ptr);
>  
>      tcg_out_mov(s, TCG_TYPE_I64, TCG_REG_X0, TCG_AREG0);
>      tcg_out_mov(s, TARGET_LONG_BITS == 64, TCG_REG_X1, lb->addrlo_reg);
>      tcg_out_movi(s, TCG_TYPE_I32, TCG_REG_X2, lb->mem_index);
> -    tcg_out_adr(s, TCG_REG_X3, (intptr_t)lb->raddr);
> -    tcg_out_call(s, (intptr_t)qemu_ld_helpers[opc & ~MO_SIGN]);
> +    tcg_out_adr(s, TCG_REG_X3, lb->raddr);
> +    tcg_out_call(s, qemu_ld_helpers[opc & ~MO_SIGN]);
>      if (opc & MO_SIGN) {
>          tcg_out_sxt(s, TCG_TYPE_I64, size, lb->datalo_reg, TCG_REG_X0);
>      } else {
>          tcg_out_mov(s, size == MO_64, lb->datalo_reg, TCG_REG_X0);
>      }
>  
> -    tcg_out_goto(s, (intptr_t)lb->raddr);
> +    tcg_out_goto(s, lb->raddr);
>  }
>  
>  static void tcg_out_qemu_st_slow_path(TCGContext *s, TCGLabelQemuLdst *lb)
> @@ -1038,21 +1020,21 @@ static void tcg_out_qemu_st_slow_path(TCGContext *s, 
> TCGLabelQemuLdst *lb)
>      TCGMemOp opc = lb->opc;
>      TCGMemOp size = opc & MO_SIZE;
>  
> -    reloc_pc19(lb->label_ptr[0], (intptr_t)s->code_ptr);
> +    reloc_pc19(lb->label_ptr[0], s->code_ptr);
>  
>      tcg_out_mov(s, TCG_TYPE_I64, TCG_REG_X0, TCG_AREG0);
>      tcg_out_mov(s, TARGET_LONG_BITS == 64, TCG_REG_X1, lb->addrlo_reg);
>      tcg_out_mov(s, size == MO_64, TCG_REG_X2, lb->datalo_reg);
>      tcg_out_movi(s, TCG_TYPE_I32, TCG_REG_X3, lb->mem_index);
> -    tcg_out_adr(s, TCG_REG_X4, (intptr_t)lb->raddr);
> -    tcg_out_call(s, (intptr_t)qemu_st_helpers[opc]);
> -    tcg_out_goto(s, (intptr_t)lb->raddr);
> +    tcg_out_adr(s, TCG_REG_X4, lb->raddr);
> +    tcg_out_call(s, qemu_st_helpers[opc]);
> +    tcg_out_goto(s, lb->raddr);
>  }
>  
>  static void add_qemu_ldst_label(TCGContext *s, bool is_ld, TCGMemOp opc,
>                                  TCGReg data_reg, TCGReg addr_reg,
> -                                int mem_index,
> -                                uint8_t *raddr, uint8_t *label_ptr)
> +                                int mem_index, tcg_insn_unit *raddr,
> +                                tcg_insn_unit *label_ptr)
>  {
>      TCGLabelQemuLdst *label = new_ldst_label(s);
>  
> @@ -1070,7 +1052,8 @@ static void add_qemu_ldst_label(TCGContext *s, bool 
> is_ld, TCGMemOp opc,
>     the slow path. Generated code returns the host addend in X1,
>     clobbers X0,X2,X3,TMP. */
>  static void tcg_out_tlb_read(TCGContext *s, TCGReg addr_reg, TCGMemOp s_bits,
> -                             uint8_t **label_ptr, int mem_index, bool 
> is_read)
> +                             tcg_insn_unit **label_ptr, int mem_index,
> +                             bool is_read)
>  {
>      TCGReg base = TCG_AREG0;
>      int tlb_offset = is_read ?
> @@ -1218,7 +1201,7 @@ static void tcg_out_qemu_ld(TCGContext *s, TCGReg 
> data_reg, TCGReg addr_reg,
>  {
>  #ifdef CONFIG_SOFTMMU
>      TCGMemOp s_bits = memop & MO_SIZE;
> -    uint8_t *label_ptr;
> +    tcg_insn_unit *label_ptr;
>  
>      tcg_out_tlb_read(s, addr_reg, s_bits, &label_ptr, mem_index, 1);
>      tcg_out_qemu_ld_direct(s, memop, data_reg, addr_reg, TCG_REG_X1);
> @@ -1235,7 +1218,7 @@ static void tcg_out_qemu_st(TCGContext *s, TCGReg 
> data_reg, TCGReg addr_reg,
>  {
>  #ifdef CONFIG_SOFTMMU
>      TCGMemOp s_bits = memop & MO_SIZE;
> -    uint8_t *label_ptr;
> +    tcg_insn_unit *label_ptr;
>  
>      tcg_out_tlb_read(s, addr_reg, s_bits, &label_ptr, mem_index, 0);
>      tcg_out_qemu_st_direct(s, memop, data_reg, addr_reg, TCG_REG_X1);
> @@ -1247,7 +1230,7 @@ static void tcg_out_qemu_st(TCGContext *s, TCGReg 
> data_reg, TCGReg addr_reg,
>  #endif /* CONFIG_SOFTMMU */
>  }
>  
> -static uint8_t *tb_ret_addr;
> +static tcg_insn_unit *tb_ret_addr;
>  
>  static void tcg_out_op(TCGContext *s, TCGOpcode opc,
>                         const TCGArg args[TCG_MAX_OP_ARGS],
> @@ -1270,7 +1253,7 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc,
>      switch (opc) {
>      case INDEX_op_exit_tb:
>          tcg_out_movi(s, TCG_TYPE_I64, TCG_REG_X0, a0);
> -        tcg_out_goto(s, (intptr_t)tb_ret_addr);
> +        tcg_out_goto(s, tb_ret_addr);
>          break;
>  
>      case INDEX_op_goto_tb:
> @@ -1278,16 +1261,16 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc,
>  #error "USE_DIRECT_JUMP required for aarch64"
>  #endif
>          assert(s->tb_jmp_offset != NULL); /* consistency for USE_DIRECT_JUMP 
> */
> -        s->tb_jmp_offset[a0] = s->code_ptr - s->code_buf;
> +        s->tb_jmp_offset[a0] = tcg_current_code_size(s);
>          /* actual branch destination will be patched by
>             aarch64_tb_set_jmp_target later, beware retranslation. */
>          tcg_out_goto_noaddr(s);
> -        s->tb_next_offset[a0] = s->code_ptr - s->code_buf;
> +        s->tb_next_offset[a0] = tcg_current_code_size(s);
>          break;
>  
>      case INDEX_op_call:
>          if (const_args[0]) {
> -            tcg_out_call(s, a0);
> +            tcg_out_call(s, (tcg_insn_unit *)(intptr_t)a0);
>          } else {
>              tcg_out_callr(s, a0);
>          }
> diff --git a/tcg/aarch64/tcg-target.h b/tcg/aarch64/tcg-target.h
> index a1d4322..a32aea6 100644
> --- a/tcg/aarch64/tcg-target.h
> +++ b/tcg/aarch64/tcg-target.h
> @@ -13,6 +13,7 @@
>  #ifndef TCG_TARGET_AARCH64
>  #define TCG_TARGET_AARCH64 1
>  
> +#define TCG_TARGET_INSN_UNIT_SIZE  4
>  #undef TCG_TARGET_STACK_GROWSUP
>  
>  typedef enum {
> 

Acked-by: Claudio Fontana <address@hidden>