Re: [Qemu-devel] [PATCH 3/5] tcg-i386: Implement movcond

[Aurelien Jarno <aurelien@aurel32.net>]

On Tue, Sep 18, 2012 at 07:23:58AM -0700, Richard Henderson wrote:
> Signed-off-by: Richard Henderson <rth@twiddle.net>
> ---
>  tcg/i386/tcg-target.c | 29 +++++++++++++++++++++++++++++
>  tcg/i386/tcg-target.h |  7 ++++++-
>  2 files changed, 35 insertions(+), 1 deletion(-)
> 
> diff --git a/tcg/i386/tcg-target.c b/tcg/i386/tcg-target.c
> index 34c2df8..cf28f56 100644
> --- a/tcg/i386/tcg-target.c
> +++ b/tcg/i386/tcg-target.c
> @@ -249,6 +249,7 @@ static inline int tcg_target_const_match(tcg_target_long val,
>  #define OPC_ADD_GvEv	(OPC_ARITH_GvEv | (ARITH_ADD << 3))
>  #define OPC_BSWAP	(0xc8 | P_EXT)
>  #define OPC_CALL_Jz	(0xe8)
> +#define OPC_CMOVCC      (0x40 | P_EXT)  /* ... plus condition code */
>  #define OPC_CMP_GvEv	(OPC_ARITH_GvEv | (ARITH_CMP << 3))
>  #define OPC_DEC_r32	(0x48)
>  #define OPC_IMUL_GvEv	(0xaf | P_EXT)
> @@ -935,6 +936,24 @@ static void tcg_out_setcond2(TCGContext *s, const TCGArg *args,
>  }
>  #endif
>  
> +static void tcg_out_movcond32(TCGContext *s, TCGCond cond, TCGArg dest,
> +                              TCGArg c1, TCGArg c2, int const_c2,
> +                              TCGArg v1)
> +{
> +    tcg_out_cmp(s, c1, c2, const_c2, 0);
> +    tcg_out_modrm(s, OPC_CMOVCC | tcg_cond_to_jcc[cond], dest, v1);
> +}
> +
> +#if TCG_TARGET_REG_BITS == 64
> +static void tcg_out_movcond64(TCGContext *s, TCGCond cond, TCGArg dest,
> +                              TCGArg c1, TCGArg c2, int const_c2,
> +                              TCGArg v1)
> +{
> +    tcg_out_cmp(s, c1, c2, const_c2, P_REXW);
> +    tcg_out_modrm(s, OPC_CMOVCC | tcg_cond_to_jcc[cond] | P_REXW, dest, v1);
> +}
> +#endif
> +
>  static void tcg_out_branch(TCGContext *s, int call, tcg_target_long dest)
>  {
>      tcg_target_long disp = dest - (tcg_target_long)s->code_ptr - 5;
> @@ -1650,6 +1669,10 @@ static inline void tcg_out_op(TCGContext *s, TCGOpcode opc,
>          tcg_out_setcond32(s, args[3], args[0], args[1],
>                            args[2], const_args[2]);
>          break;
> +    case INDEX_op_movcond_i32:
> +        tcg_out_movcond32(s, args[5], args[0], args[1],
> +                          args[2], const_args[2], args[3]);
> +        break;
>  
>      OP_32_64(bswap16):
>          tcg_out_rolw_8(s, args[0]);
> @@ -1772,6 +1795,10 @@ static inline void tcg_out_op(TCGContext *s, TCGOpcode opc,
>          tcg_out_setcond64(s, args[3], args[0], args[1],
>                            args[2], const_args[2]);
>          break;
> +    case INDEX_op_movcond_i64:
> +        tcg_out_movcond64(s, args[5], args[0], args[1],
> +                          args[2], const_args[2], args[3]);
> +        break;
>  
>      case INDEX_op_bswap64_i64:
>          tcg_out_bswap64(s, args[0]);
> @@ -1856,6 +1883,7 @@ static const TCGTargetOpDef x86_op_defs[] = {
>      { INDEX_op_setcond_i32, { "q", "r", "ri" } },
>  
>      { INDEX_op_deposit_i32, { "Q", "0", "Q" } },
> +    { INDEX_op_movcond_i32, { "r", "r", "ri", "r", "0" } },
>  
>  #if TCG_TARGET_REG_BITS == 32
>      { INDEX_op_mulu2_i32, { "a", "d", "a", "r" } },
> @@ -1910,6 +1938,7 @@ static const TCGTargetOpDef x86_op_defs[] = {
>      { INDEX_op_ext32u_i64, { "r", "r" } },
>  
>      { INDEX_op_deposit_i64, { "Q", "0", "Q" } },
> +    { INDEX_op_movcond_i64, { "r", "r", "re", "r", "0" } },
>  #endif
>  
>  #if TCG_TARGET_REG_BITS == 64
> diff --git a/tcg/i386/tcg-target.h b/tcg/i386/tcg-target.h
> index 504f953..b356d76 100644
> --- a/tcg/i386/tcg-target.h
> +++ b/tcg/i386/tcg-target.h
> @@ -86,7 +86,12 @@ typedef enum {
>  #define TCG_TARGET_HAS_nand_i32         0
>  #define TCG_TARGET_HAS_nor_i32          0
>  #define TCG_TARGET_HAS_deposit_i32      1
> +#if defined(__x86_64__) || defined(__i686__)
> +/* Use cmov only if the compiler is already doing so.  */
> +#define TCG_TARGET_HAS_movcond_i32      1
> +#else
>  #define TCG_TARGET_HAS_movcond_i32      0
> +#endif
>  
>  #if TCG_TARGET_REG_BITS == 64
>  #define TCG_TARGET_HAS_div2_i64         1
> @@ -108,7 +113,7 @@ typedef enum {
>  #define TCG_TARGET_HAS_nand_i64         0
>  #define TCG_TARGET_HAS_nor_i64          0
>  #define TCG_TARGET_HAS_deposit_i64      1
> -#define TCG_TARGET_HAS_movcond_i64      0
> +#define TCG_TARGET_HAS_movcond_i64      1
>  #endif
>  
>  #define TCG_TARGET_deposit_i32_valid(ofs, len) \
> -- 
> 1.7.11.4
> 

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>

-- 
Aurelien Jarno                          GPG: 1024D/F1BCDB73
aurelien@aurel32.net                 http://www.aurel32.net