Re: [PATCH v3 34/38] tcg/ppc: Support TCG_COND_TST{EQ,NE}

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 10/1/24 23:44, Richard Henderson wrote:
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>   tcg/ppc/tcg-target.h     |   2 +-
>   tcg/ppc/tcg-target.c.inc | 122 ++++++++++++++++++++++++++++++++++++---
>   2 files changed, 115 insertions(+), 9 deletions(-)
> 
> diff --git a/tcg/ppc/tcg-target.h b/tcg/ppc/tcg-target.h
> index 60ce49e672..04a7aba4d3 100644
> --- a/tcg/ppc/tcg-target.h
> +++ b/tcg/ppc/tcg-target.h
> @@ -143,7 +143,7 @@ typedef enum {
>   #define TCG_TARGET_HAS_qemu_ldst_i128   \
>       (TCG_TARGET_REG_BITS == 64 && have_isa_2_07)
>   
> -#define TCG_TARGET_HAS_tst              0
> +#define TCG_TARGET_HAS_tst              1
>   
>   /*
>    * While technically Altivec could support V64, it has no 64-bit store
> diff --git a/tcg/ppc/tcg-target.c.inc b/tcg/ppc/tcg-target.c.inc
> index 535ef2cbe7..7f3829beeb 100644
> --- a/tcg/ppc/tcg-target.c.inc
> +++ b/tcg/ppc/tcg-target.c.inc
> @@ -283,11 +283,15 @@ static bool reloc_pc34(tcg_insn_unit *src_rw, const tcg_insn_unit *target)
>       return false;
>   }
>   
> +static bool mask_operand(uint32_t c, int *mb, int *me);
> +static bool mask64_operand(uint64_t c, int *mb, int *me);
> +
>   /* test if a constant matches the constraint */
>   static bool tcg_target_const_match(int64_t sval, int ct,
>                                      TCGType type, TCGCond cond, int vece)
>   {
>       uint64_t uval = sval;
> +    int mb, me;
>   
>       if (ct & TCG_CT_CONST) {
>           return 1;
> @@ -316,6 +320,17 @@ static bool tcg_target_const_match(int64_t sval, int ct,
>           case TCG_COND_GTU:
>               ct |= TCG_CT_CONST_U16;
>               break;
> +        case TCG_COND_TSTEQ:
> +        case TCG_COND_TSTNE:
> +            if ((uval & ~0xffff) == 0 || (uval & ~0xffff0000ull) == 0) {
> +                return 1;
> +            }
> +            if (TCG_TARGET_REG_BITS == 32 || type == TCG_TYPE_I32
> +                ? mask_operand(uval, &mb, &me)
> +                : mask64_operand(uval << clz64(uval), &mb, &me)) {
> +                return 1;
> +            }
> +            return 0;
>           default:
>               g_assert_not_reached();
>           }
> @@ -703,9 +718,11 @@ enum {
>       CR_SO
>   };
>   
> -static const uint32_t tcg_to_bc[] = {
> +static const uint32_t tcg_to_bc[16] = {
>       [TCG_COND_EQ]  = BC | BI(0, CR_EQ) | BO_COND_TRUE,
>       [TCG_COND_NE]  = BC | BI(0, CR_EQ) | BO_COND_FALSE,
> +    [TCG_COND_TSTEQ]  = BC | BI(0, CR_EQ) | BO_COND_TRUE,
> +    [TCG_COND_TSTNE]  = BC | BI(0, CR_EQ) | BO_COND_FALSE,
>       [TCG_COND_LT]  = BC | BI(0, CR_LT) | BO_COND_TRUE,
>       [TCG_COND_GE]  = BC | BI(0, CR_LT) | BO_COND_FALSE,
>       [TCG_COND_LE]  = BC | BI(0, CR_GT) | BO_COND_FALSE,
> @@ -717,9 +734,11 @@ static const uint32_t tcg_to_bc[] = {
>   };
>   
>   /* The low bit here is set if the RA and RB fields must be inverted.  */
> -static const uint32_t tcg_to_isel[] = {
> +static const uint32_t tcg_to_isel[16] = {
>       [TCG_COND_EQ]  = ISEL | BC_(0, CR_EQ),
>       [TCG_COND_NE]  = ISEL | BC_(0, CR_EQ) | 1,
> +    [TCG_COND_TSTEQ] = ISEL | BC_(0, CR_EQ),
> +    [TCG_COND_TSTNE] = ISEL | BC_(0, CR_EQ) | 1,
>       [TCG_COND_LT]  = ISEL | BC_(0, CR_LT),
>       [TCG_COND_GE]  = ISEL | BC_(0, CR_LT) | 1,
>       [TCG_COND_LE]  = ISEL | BC_(0, CR_GT) | 1,
> @@ -872,19 +891,31 @@ static bool tcg_out_mov(TCGContext *s, TCGType type, TCGReg ret, TCGReg arg)
>       return true;
>   }
>   
> -static inline void tcg_out_rld(TCGContext *s, int op, TCGReg ra, TCGReg rs,
> -                               int sh, int mb)
> +static void tcg_out_rld_rc(TCGContext *s, int op, TCGReg ra, TCGReg rs,
> +                           int sh, int mb, bool rc)
>   {
>       tcg_debug_assert(TCG_TARGET_REG_BITS == 64);
>       sh = SH(sh & 0x1f) | (((sh >> 5) & 1) << 1);
>       mb = MB64((mb >> 5) | ((mb << 1) & 0x3f));
> -    tcg_out32(s, op | RA(ra) | RS(rs) | sh | mb);
> +    tcg_out32(s, op | RA(ra) | RS(rs) | sh | mb | rc);
>   }
>   
> -static inline void tcg_out_rlw(TCGContext *s, int op, TCGReg ra, TCGReg rs,
> -                               int sh, int mb, int me)
> +static void tcg_out_rld(TCGContext *s, int op, TCGReg ra, TCGReg rs,
> +                        int sh, int mb)
>   {
> -    tcg_out32(s, op | RA(ra) | RS(rs) | SH(sh) | MB(mb) | ME(me));
> +    tcg_out_rld_rc(s, op, ra, rs, sh, mb, false);
> +}
> +
> +static void tcg_out_rlw_rc(TCGContext *s, int op, TCGReg ra, TCGReg rs,
> +                           int sh, int mb, int me, bool rc)
> +{
> +    tcg_out32(s, op | RA(ra) | RS(rs) | SH(sh) | MB(mb) | ME(me) | rc);
> +}
> +
> +static void tcg_out_rlw(TCGContext *s, int op, TCGReg ra, TCGReg rs,
> +                        int sh, int mb, int me)
> +{
> +    tcg_out_rlw_rc(s, op, ra, rs, sh, mb, me, false);
>   }
>   
>   static void tcg_out_ext8s(TCGContext *s, TCGType type, TCGReg dst, TCGReg src)
> @@ -1702,6 +1733,50 @@ static inline bool tcg_out_sti(TCGContext *s, TCGType type, TCGArg val,
>       return false;
>   }
>   
> +/*
> + * Set dest non-zero if and only if (arg1 & arg2) is non-zero.
> + * If RC, then also set RC0.
> + */
> +static void tcg_out_test(TCGContext *s, TCGReg dest, TCGReg arg1, TCGArg arg2,
> +                         bool const_arg2, TCGType type, bool rc)
> +{
> +    int mb, me;
> +
> +    if (!const_arg2) {
> +        tcg_out32(s, AND | SAB(arg1, dest, arg2) | rc);
> +        return;
> +    }
> +
> +    if (type == TCG_TYPE_I32) {
> +        arg2 = (uint32_t)arg2;
> +    } else if (arg2 == (uint32_t)arg2) {
> +        type = TCG_TYPE_I32;
> +    }
> +
> +    if ((arg2 & ~0xffff) == 0) {
> +        tcg_out32(s, ANDI | SAI(arg1, dest, arg2));
> +        return;
> +    }
> +    if ((arg2 & ~0xffff0000ull) == 0) {
> +        tcg_out32(s, ANDIS | SAI(arg1, dest, arg2 >> 16));
> +        return;
> +    }
> +    if (TCG_TARGET_REG_BITS == 32 || type == TCG_TYPE_I32) {
> +        if (mask_operand(arg2, &mb, &me)) {
> +            tcg_out_rlw_rc(s, RLWINM, dest, arg1, 0, mb, me, rc);
> +            return;
> +        }
> +    } else {
> +        int sh = clz64(arg2);
> +        if (mask64_operand(arg2 << sh, &mb, &me)) {
> +            tcg_out_rld_rc(s, RLDICR, dest, arg1, sh, me, rc);
> +            return;
> +        }
> +    }
> +    /* Constraints should satisfy this. */
> +    g_assert_not_reached();
> +}
> +
>   static void tcg_out_cmp(TCGContext *s, int cond, TCGArg arg1, TCGArg arg2,
>                           int const_arg2, int cr, TCGType type)
>   {
> @@ -1736,6 +1811,12 @@ static void tcg_out_cmp(TCGContext *s, int cond, TCGArg arg1, TCGArg arg2,
>           imm = 0;
>           break;
>   
> +    case TCG_COND_TSTEQ:
> +    case TCG_COND_TSTNE:
> +        tcg_debug_assert(cr == 0);
> +        tcg_out_test(s, TCG_REG_R0, arg1, arg2, const_arg2, type, true);
> +        return;
> +
>       case TCG_COND_LT:
>       case TCG_COND_GE:
>       case TCG_COND_LE:
> @@ -1946,6 +2027,16 @@ static void tcg_out_setcond(TCGContext *s, TCGType type, TCGCond cond,
>           tcg_out_setcond_ne0(s, type, arg0, arg1, neg);
>           break;
>   
> +    case TCG_COND_TSTEQ:
> +        tcg_out_test(s, TCG_REG_R0, arg1, arg2, const_arg2, type, false);
> +        tcg_out_setcond_eq0(s, type, arg0, TCG_REG_R0, neg);
> +        break;
> +
> +    case TCG_COND_TSTNE:
> +        tcg_out_test(s, TCG_REG_R0, arg1, arg2, const_arg2, type, false);
> +        tcg_out_setcond_ne0(s, type, arg0, TCG_REG_R0, neg);
> +        break;
> +
>       case TCG_COND_LE:
>       case TCG_COND_LEU:
>           inv = true;
> @@ -2118,6 +2209,21 @@ static void tcg_out_cmp2(TCGContext *s, const TCGArg *args,
>           tcg_out32(s, op | BT(0, CR_EQ) | BA(6, CR_EQ) | BB(7, CR_EQ));
>           break;
>   
> +    case TCG_COND_TSTEQ:
> +    case TCG_COND_TSTNE:
> +        if (blconst) {
> +            tcg_out_andi32(s, TCG_REG_R0, al, bl);
> +        } else {
> +            tcg_out32(s, AND | SAB(al, TCG_REG_R0, bl));
> +        }
> +        if (bhconst) {
> +            tcg_out_andi32(s, TCG_REG_TMP1, ah, bh);
> +        } else {
> +            tcg_out32(s, AND | SAB(ah, TCG_REG_TMP1, bh));
> +        }
> +        tcg_out32(s, OR | SAB(TCG_REG_R0, TCG_REG_R0, TCG_REG_TMP1) | 1);
> +        break;
> +
>       case TCG_COND_LT:
>       case TCG_COND_LE:
>       case TCG_COND_GT:

To the best of my PPC knowledge:

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>