Re: [Qemu-devel] [PATCH v3 11/16] tcg: Return success from patch_reloc

["Alex Bennée" <alex.bennee@linaro.org>]

Richard Henderson <richard.henderson@linaro.org> writes:

> This will move the assert for success from within (subroutines of)
> patch_reloc into the callers.  It will also let new code do something
> different when a relocation is out of range.
>
> For the moment, all backends are trivially converted to return true.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>

> ---
>  tcg/aarch64/tcg-target.inc.c | 3 ++-
>  tcg/arm/tcg-target.inc.c     | 3 ++-
>  tcg/i386/tcg-target.inc.c    | 3 ++-
>  tcg/mips/tcg-target.inc.c    | 3 ++-
>  tcg/ppc/tcg-target.inc.c     | 3 ++-
>  tcg/s390/tcg-target.inc.c    | 3 ++-
>  tcg/sparc/tcg-target.inc.c   | 5 +++--
>  tcg/tcg.c                    | 8 +++++---
>  tcg/tci/tcg-target.inc.c     | 3 ++-
>  9 files changed, 22 insertions(+), 12 deletions(-)
>
> diff --git a/tcg/aarch64/tcg-target.inc.c b/tcg/aarch64/tcg-target.inc.c
> index 28de0226fb..16f08c59c4 100644
> --- a/tcg/aarch64/tcg-target.inc.c
> +++ b/tcg/aarch64/tcg-target.inc.c
> @@ -94,7 +94,7 @@ static inline void reloc_pc19(tcg_insn_unit *code_ptr, tcg_insn_unit *target)
>      *code_ptr = deposit32(*code_ptr, 5, 19, offset);
>  }
>
> -static inline void patch_reloc(tcg_insn_unit *code_ptr, int type,
> +static inline bool patch_reloc(tcg_insn_unit *code_ptr, int type,
>                                 intptr_t value, intptr_t addend)
>  {
>      tcg_debug_assert(addend == 0);
> @@ -109,6 +109,7 @@ static inline void patch_reloc(tcg_insn_unit *code_ptr, int type,
>      default:
>          tcg_abort();
>      }
> +    return true;
>  }
>
>  #define TCG_CT_CONST_AIMM 0x100
> diff --git a/tcg/arm/tcg-target.inc.c b/tcg/arm/tcg-target.inc.c
> index 1651f00281..deefa20fbf 100644
> --- a/tcg/arm/tcg-target.inc.c
> +++ b/tcg/arm/tcg-target.inc.c
> @@ -193,7 +193,7 @@ static inline void reloc_pc24(tcg_insn_unit *code_ptr, tcg_insn_unit *target)
>      *code_ptr = (*code_ptr & ~0xffffff) | (offset & 0xffffff);
>  }
>
> -static void patch_reloc(tcg_insn_unit *code_ptr, int type,
> +static bool patch_reloc(tcg_insn_unit *code_ptr, int type,
>                          intptr_t value, intptr_t addend)
>  {
>      tcg_debug_assert(addend == 0);
> @@ -229,6 +229,7 @@ static void patch_reloc(tcg_insn_unit *code_ptr, int type,
>      } else {
>          g_assert_not_reached();
>      }
> +    return true;
>  }
>
>  #define TCG_CT_CONST_ARM  0x100
> diff --git a/tcg/i386/tcg-target.inc.c b/tcg/i386/tcg-target.inc.c
> index 436195894b..5c88f1f36b 100644
> --- a/tcg/i386/tcg-target.inc.c
> +++ b/tcg/i386/tcg-target.inc.c
> @@ -167,7 +167,7 @@ static bool have_lzcnt;
>
>  static tcg_insn_unit *tb_ret_addr;
>
> -static void patch_reloc(tcg_insn_unit *code_ptr, int type,
> +static bool patch_reloc(tcg_insn_unit *code_ptr, int type,
>                          intptr_t value, intptr_t addend)
>  {
>      value += addend;
> @@ -191,6 +191,7 @@ static void patch_reloc(tcg_insn_unit *code_ptr, int type,
>      default:
>          tcg_abort();
>      }
> +    return true;
>  }
>
>  #if TCG_TARGET_REG_BITS == 64
> diff --git a/tcg/mips/tcg-target.inc.c b/tcg/mips/tcg-target.inc.c
> index e21cb1ae28..a06ff257fa 100644
> --- a/tcg/mips/tcg-target.inc.c
> +++ b/tcg/mips/tcg-target.inc.c
> @@ -168,12 +168,13 @@ static inline void reloc_26(tcg_insn_unit *pc, tcg_insn_unit *target)
>      *pc = deposit32(*pc, 0, 26, reloc_26_val(pc, target));
>  }
>
> -static void patch_reloc(tcg_insn_unit *code_ptr, int type,
> +static bool patch_reloc(tcg_insn_unit *code_ptr, int type,
>                          intptr_t value, intptr_t addend)
>  {
>      tcg_debug_assert(type == R_MIPS_PC16);
>      tcg_debug_assert(addend == 0);
>      reloc_pc16(code_ptr, (tcg_insn_unit *)value);
> +    return true;
>  }
>
>  #define TCG_CT_CONST_ZERO 0x100
> diff --git a/tcg/ppc/tcg-target.inc.c b/tcg/ppc/tcg-target.inc.c
> index 2e2a22f579..860b0d36e1 100644
> --- a/tcg/ppc/tcg-target.inc.c
> +++ b/tcg/ppc/tcg-target.inc.c
> @@ -513,7 +513,7 @@ static const uint32_t tcg_to_isel[] = {
>      [TCG_COND_GTU] = ISEL | BC_(7, CR_GT),
>  };
>
> -static void patch_reloc(tcg_insn_unit *code_ptr, int type,
> +static bool patch_reloc(tcg_insn_unit *code_ptr, int type,
>                          intptr_t value, intptr_t addend)
>  {
>      tcg_insn_unit *target;
> @@ -548,6 +548,7 @@ static void patch_reloc(tcg_insn_unit *code_ptr, int type,
>      default:
>          g_assert_not_reached();
>      }
> +    return true;
>  }
>
>  static void tcg_out_mem_long(TCGContext *s, int opi, int opx, TCGReg rt,
> diff --git a/tcg/s390/tcg-target.inc.c b/tcg/s390/tcg-target.inc.c
> index 96c344142e..68a4c60394 100644
> --- a/tcg/s390/tcg-target.inc.c
> +++ b/tcg/s390/tcg-target.inc.c
> @@ -366,7 +366,7 @@ static void * const qemu_st_helpers[16] = {
>  static tcg_insn_unit *tb_ret_addr;
>  uint64_t s390_facilities;
>
> -static void patch_reloc(tcg_insn_unit *code_ptr, int type,
> +static bool patch_reloc(tcg_insn_unit *code_ptr, int type,
>                          intptr_t value, intptr_t addend)
>  {
>      intptr_t pcrel2;
> @@ -393,6 +393,7 @@ static void patch_reloc(tcg_insn_unit *code_ptr, int type,
>      default:
>          g_assert_not_reached();
>      }
> +    return true;
>  }
>
>  /* parse target specific constraints */
> diff --git a/tcg/sparc/tcg-target.inc.c b/tcg/sparc/tcg-target.inc.c
> index 671a04c54b..cadda770c4 100644
> --- a/tcg/sparc/tcg-target.inc.c
> +++ b/tcg/sparc/tcg-target.inc.c
> @@ -291,7 +291,7 @@ static inline int check_fit_i32(int32_t val, unsigned int bits)
>  # define check_fit_ptr  check_fit_i32
>  #endif
>
> -static void patch_reloc(tcg_insn_unit *code_ptr, int type,
> +static bool patch_reloc(tcg_insn_unit *code_ptr, int type,
>                          intptr_t value, intptr_t addend)
>  {
>      uint32_t insn = *code_ptr;
> @@ -328,12 +328,13 @@ static void patch_reloc(tcg_insn_unit *code_ptr, int type,
>          /* Note that we're abusing this reloc type for our own needs.  */
>          code_ptr[0] = deposit32(code_ptr[0], 0, 22, value >> 10);
>          code_ptr[1] = deposit32(code_ptr[1], 0, 10, value);
> -        return;
> +        return true;
>      default:
>          g_assert_not_reached();
>      }
>
>      *code_ptr = insn;
> +    return true;
>  }
>
>  /* parse target specific constraints */
> diff --git a/tcg/tcg.c b/tcg/tcg.c
> index e85133ef05..54f1272187 100644
> --- a/tcg/tcg.c
> +++ b/tcg/tcg.c
> @@ -66,7 +66,7 @@
>  static void tcg_target_init(TCGContext *s);
>  static const TCGTargetOpDef *tcg_target_op_def(TCGOpcode);
>  static void tcg_target_qemu_prologue(TCGContext *s);
> -static void patch_reloc(tcg_insn_unit *code_ptr, int type,
> +static bool patch_reloc(tcg_insn_unit *code_ptr, int type,
>                          intptr_t value, intptr_t addend);
>
>  /* The CIE and FDE header definitions will be common to all hosts.  */
> @@ -268,7 +268,8 @@ static void tcg_out_reloc(TCGContext *s, tcg_insn_unit *code_ptr, int type,
>          /* FIXME: This may break relocations on RISC targets that
>             modify instruction fields in place.  The caller may not have
>             written the initial value.  */
> -        patch_reloc(code_ptr, type, l->u.value, addend);
> +        bool ok = patch_reloc(code_ptr, type, l->u.value, addend);
> +        tcg_debug_assert(ok);
>      } else {
>          /* add a new relocation entry */
>          r = tcg_malloc(sizeof(TCGRelocation));
> @@ -288,7 +289,8 @@ static void tcg_out_label(TCGContext *s, TCGLabel *l, tcg_insn_unit *ptr)
>      tcg_debug_assert(!l->has_value);
>
>      for (r = l->u.first_reloc; r != NULL; r = r->next) {
> -        patch_reloc(r->ptr, r->type, value, r->addend);
> +        bool ok = patch_reloc(r->ptr, r->type, value, r->addend);
> +        tcg_debug_assert(ok);
>      }
>
>      l->has_value = 1;
> diff --git a/tcg/tci/tcg-target.inc.c b/tcg/tci/tcg-target.inc.c
> index 62ed097254..0015a98485 100644
> --- a/tcg/tci/tcg-target.inc.c
> +++ b/tcg/tci/tcg-target.inc.c
> @@ -369,7 +369,7 @@ static const char *const tcg_target_reg_names[TCG_TARGET_NB_REGS] = {
>  };
>  #endif
>
> -static void patch_reloc(tcg_insn_unit *code_ptr, int type,
> +static bool patch_reloc(tcg_insn_unit *code_ptr, int type,
>                          intptr_t value, intptr_t addend)
>  {
>      /* tcg_out_reloc always uses the same type, addend. */
> @@ -381,6 +381,7 @@ static void patch_reloc(tcg_insn_unit *code_ptr, int type,
>      } else {
>          tcg_patch64(code_ptr, value);
>      }
> +    return true;
>  }
>
>  /* Parse target specific constraints. */


--
Alex Bennée