Re: [PATCH 3/5 ver4] RS6000: Add TI to TD (128-bit DFP) and TD to TI support

[will schmidt <will_schmidt@vnet.ibm.com>]

On Mon, 2021-04-26 at 09:36 -0700, Carl Love wrote:
> Will, Segher:
> 


Hi,


> This patch adds support for converting to/from 128-bit integers and
> 128-bit decimal floating point formats.


You reference TI,TD in the subject, would be helpful to elaborate a bit in your description.


> 
> The patch has been tested on
>     powerpc64-linux instead (Power 8 BE)
>     powerpc64-linux instead (Power 9 LE)
>     powerpc64-linux instead (Power 10 LE)
> 
> Please let me know if the patch is acceptable for mainline.
> 
>                    Carl Love
> ------------------------------------------------
> 
> gcc/ChangeLog
> dje.gcc@gmail.com, gcc-patches@gcc.gnu.org, Bill Schmidt <wschmidt@linux.vnet.ibm.com>, Peter Bergner <bergner@vnet.ibm.com>,  
> 2021-04-26  Carl Love  <cel@us.ibm.com>


Something there seems wrong.

>         * config/rs6000/dfp.md (floattitd2, fixtdti2): New define_insns.


>         * config/rs6000/rs6000-call.c (P10V_BUILTIN_VCMPNET_P,
> 	P10V_BUILTIN_VCMPAET_P): New overloaded definitions.

I don't see this below.

> 
> gcc/testsuite/ChangeLog
> 
> 2021-04-26  Carl Love  <cel@us.ibm.com>
>         * gcc.target/powerpc/int_128bit-runnable.c: Add 128-bit DFP
>         conversion tests.

ok

> ---
>  gcc/config/rs6000/dfp.md                      | 14 +++++
>  .../gcc.target/powerpc/int_128bit-runnable.c  | 61 

> +++++++++++++++++++
>  2 files changed, 75 insertions(+)
> 
> diff --git a/gcc/config/rs6000/dfp.md b/gcc/config/rs6000/dfp.md
> index 026be5d48a6..b89d5ecc91d 100644
> --- a/gcc/config/rs6000/dfp.md
> +++ b/gcc/config/rs6000/dfp.md
> @@ -226,6 +226,13 @@
>    [(set_attr "type" "dfp")
>     (set_attr "size" "128")])
> 
> +(define_insn "floattitd2"
> +  [(set (match_operand:TD 0 "gpc_reg_operand" "=d")
> +	(float:TD (match_operand:TI 1 "gpc_reg_operand" "v")))]
> +  "TARGET_POWER10"
> +  "dcffixqq %0,%1"
> +  [(set_attr "type" "dfp")])
> +
>  ;; Convert a decimal64/128 to a decimal64/128 whose value is an integer.
>  ;; This is the first stage of converting it to an integer type.
> 
> @@ -247,6 +254,13 @@
>    "dctfix<q> %0,%1"
>    [(set_attr "type" "dfp")
>     (set_attr "size" "<bits>")])
> +
> +(define_insn "fixtdti2"
> +  [(set (match_operand:TI 0 "gpc_reg_operand" "=v")
> +	(fix:TI (match_operand:TD 1 "gpc_reg_operand" "d")))]
> +  "TARGET_POWER10"
> +  "dctfixqq %0,%1"
> +  [(set_attr "type" "dfp")])

ok


>  
>  ;; Decimal builtin support
> 
> diff --git a/gcc/testsuite/gcc.target/powerpc/int_128bit-runnable.c b/gcc/testsuite/gcc.target/powerpc/int_128bit-runnable.c
> index 042758c8684..625b3869118 100644
> --- a/gcc/testsuite/gcc.target/powerpc/int_128bit-runnable.c
> +++ b/gcc/testsuite/gcc.target/powerpc/int_128bit-runnable.c
> @@ -37,6 +37,7 @@
>  #if DEBUG
>  #include <stdio.h>
>  #include <stdlib.h>
> +#include <math.h>
> 
> 
>  void print_i128(__int128_t val)
> @@ -58,6 +59,13 @@ int main ()
>    __int128_t arg1, result;
>    __uint128_t uarg2;
> 
> +  _Decimal128 arg1_dfp128, result_dfp128, expected_result_dfp128;
> +
> +  struct conv_t {
> +    __uint128_t u128;
> +    _Decimal128 d128;
> +  } conv, conv2;
> +
>    vector signed long long int vec_arg1_di, vec_arg2_di;
>    vector signed long long int vec_result_di, vec_expected_result_di;
>    vector unsigned long long int vec_uarg1_di, vec_uarg2_di, vec_uarg3_di;
> @@ -2258,6 +2266,59 @@ int main ()
>      abort();
>  #endif
>    }
> +  
> +  /* DFP to __int128 and __int128 to DFP conversions */
> +  /* Print the DFP value as an unsigned int so we can see the bit patterns.  */
> +  conv.u128 = 0x2208000000000000ULL;
> +  conv.u128 = (conv.u128 << 64) | 0x4ULL;   //DFP bit pattern for integer 4
> +  expected_result_dfp128 = conv.d128;
> 
> +  arg1 = 4;
> +
> +  conv.d128 = (_Decimal128) arg1;
> +
> +  result_dfp128 = (_Decimal128) arg1;
> +  if (((conv.u128 >>64) != 0x2208000000000000ULL) &&
> +      ((conv.u128 & 0xFFFFFFFFFFFFFFFF) != 0x4ULL)) {
> +#if DEBUG
> +    printf("ERROR:  convert int128 value ");
> +    print_i128 (arg1);
> +    conv.d128 = result_dfp128;
> +    printf("\nto DFP value 0x%llx %llx (printed as hex bit string) ",
> +	   (unsigned long long)((conv.u128) >>64),
> +	   (unsigned long long)((conv.u128) & 0xFFFFFFFFFFFFFFFF));
> +
> +    conv.d128 = expected_result_dfp128;
> +    printf("\ndoes not match expected_result = 0x%llx %llx\n\n",
> +	   (unsigned long long) (conv.u128>>64),
> +	   (unsigned long long) (conv.u128 & 0xFFFFFFFFFFFFFFFF));
> +#else

> +    abort();
> +#endif
> +  }
> +
> +  expected_result = 4;
> +
> +  conv.u128 = 0x2208000000000000ULL;
> +  conv.u128 = (conv.u128 << 64) | 0x4ULL;  // 4 as DFP
> +  arg1_dfp128 = conv.d128;
> +
> +  result = (__int128_t) arg1_dfp128;
> +
> +  if (result != expected_result) {
> +#if DEBUG
> +    printf("ERROR:  convert DFP value ");
> +    printf("0x%llx %llx (printed as hex bit string) ",
> +	   (unsigned long long)(conv.u128>>64),
> +	   (unsigned long long)(conv.u128 & 0xFFFFFFFFFFFFFFFF));
> +    printf("to __int128 value = ");
> +    print_i128 (result);
> +    printf("\ndoes not match expected_result = ");
> +    print_i128 (expected_result);
> +    printf("\n");
> +#else
> +    abort();
> +#endif
> +  }
>    return 0;
>  }


ok