Hi Carl,
on 2023/8/9 23:52, Carl Love wrote:
>
> GCC maintainers:
>
> The following patch adds four built-ins for the decimal floating point
> (DFP) quantize instructions on rs6000. The built-ins are for 64-bit
> and 128-bit DFP operands.
>
> The patch also adds a test case for the new builtins.
>
> The Patch has been tested on Power 10LE and Power 9 LE/BE.
>
> Please let me know if the patch is acceptable for mainline. Thanks.
>
> Carl Love
>
>
> ------------------------------------------
> rs6000, add overloaded DFP quantize support
>
> Add decimal floating point (DFP) quantize built-ins for both 64-bit DFP
> and 128-DFP operands. In each case, there is an immediate version and a
> variable version of the bult-in. The RM value is a 2-bit const int which
Nit: s/bult-in//built-in/
> specifies the rounding mode to use. For the immediate versions of the
> built-in, TE field is a 5-bit constant that specifies the value of the
> ideal exponent for the result. The built-in specifications are:
>
> __Decimal64 builtin_dfp_quantize (_Decimal64, _Decimal64,
> const int RM)
> __Decimal64 builtin_dfp_quantize (const int TE, _Decimal64,
> const int)
> __Decimal128 builtin_dfpq_quantize (_Decimal128, _Decimal128,
> const int RM)
> __Decimal128 builtin_dfpq_quantize (const int TE, _Decimal128,
> const int)
>
I noticed that the existing DFP bifs are directly using the insn
mnemonics, I perfer to keep consistent with them. So could we
have one function like unique external interface like dfp_quantize
for users' uses?
And we can have the underlying instances for it:
__Decimal64 builtin_dfp_dqua (_Decimal64, _Decimal64, const int RM)
__Decimal64 builtin_dfp_dquai (const int TE, _Decimal64, const int)
__Decimal128 builtin_dfp_dquaq (_Decimal128, _Decimal128, const int RM)
__Decimal128 builtin_dfp_dquaiq (const int TE, _Decimal128, const int)
Besides, this patch missed to update the documentation, please add them
in gcc//doc/extend.texi by searching "The following built-in functions
are available when hardware decimal floating point".
> A testcase is added for the new built-in definitions.
>
> gcc/ChangeLog:
> * config/rs6000/dfp.md: New UNSPECDQUAN.
> (dfp_quan_<mode>, dfp_quan_i<mode>): New define_insn.
> * config/rs6000/rs6000-builtins.def (__builtin_dfp_quantize_64,
> __builtin_dfp_quantize_64i, __builtin_dfp_quantize_128,
> __builtin_dfp_quantize_128i): New buit-in definitions.
> * config/rs6000/rs6000-overload.def (__builtin_dfp_quantize,
> __builtin_dfpq_quantize): New overloaded definitions.
>
> gcc/testsuite/
> * gcc.target/powerpc/builtin-dfp-quantize-runnable.c: New test
> case.
> ---
> gcc/config/rs6000/dfp.md | 25 ++-
> gcc/config/rs6000/rs6000-builtins.def | 15 ++
> gcc/config/rs6000/rs6000-overload.def | 12 ++
> .../powerpc/builtin-dfp-quantize-runnable.c | 198 ++++++++++++++++++
> 4 files changed, 249 insertions(+), 1 deletion(-)
> create mode 100644
> gcc/testsuite/gcc.target/powerpc/builtin-dfp-quantize-runnable.c
>
> diff --git a/gcc/config/rs6000/dfp.md b/gcc/config/rs6000/dfp.md
> index 5ed8a73ac51..254c22a5c20 100644
> --- a/gcc/config/rs6000/dfp.md
> +++ b/gcc/config/rs6000/dfp.md
> @@ -271,7 +271,8 @@
> UNSPEC_DIEX
> UNSPEC_DSCLI
> UNSPEC_DTSTSFI
> - UNSPEC_DSCRI])
> + UNSPEC_DSCRI
> + UNSPEC_DQUAN])
>
> (define_code_iterator DFP_TEST [eq lt gt unordered])
>
> @@ -395,3 +396,25 @@
> "dscri<q> %0,%1,%2"
> [(set_attr "type" "dfp")
> (set_attr "size" "<bits>")])
> +
> +(define_insn "dfp_quan_<mode>"
s/quan/dqua/ to aglin with the others.
> + [(set (match_operand:DDTD 0 "gpc_reg_operand" "=d")
> + (unspec:DDTD [(match_operand:DDTD 1 "gpc_reg_operand" "d")
> + (match_operand:DDTD 2 "gpc_reg_operand" "d")
> + (match_operand:QI 3 "immediate_operand" "i")]
> + UNSPEC_DQUAN))]
> + "TARGET_DFP"
> + "dqua<q> %0,%1,%2,%3"
> + [(set_attr "type" "dfp")
> + (set_attr "size" "<bits>")])
> +
> +(define_insn "dfp_quan_i<mode>"
also s/quan_i/dquai_/
> + [(set (match_operand:DDTD 0 "gpc_reg_operand" "=d")
> + (unspec:DDTD [(match_operand:SI 1 "const_int_operand" "n")
> + (match_operand:DDTD 2 "gpc_reg_operand" "d")
> + (match_operand:SI 3 "immediate_operand" "i")]
> + UNSPEC_DQUAN))]
> + "TARGET_DFP"
> + "dquai<q> %1,%0,%2,%3"
> + [(set_attr "type" "dfp")
> + (set_attr "size" "<bits>")])
> diff --git a/gcc/config/rs6000/rs6000-builtins.def
> b/gcc/config/rs6000/rs6000-builtins.def
> index 35c4cdf74c5..36a56311643 100644
> --- a/gcc/config/rs6000/rs6000-builtins.def
> +++ b/gcc/config/rs6000/rs6000-builtins.def
> @@ -2983,6 +2983,21 @@
> const unsigned long long __builtin_unpack_dec128 (_Decimal128, const
> int<1>);
> UNPACK_TD unpacktd {}
>
> + const _Decimal64 __builtin_dfp_quantize_64 (_Decimal64, _Decimal64, \
> + const int<2>);
> + DFPQUAN_64 dfp_quan_dd {}
Update with builtin_dfp_dqua and dfp_dqua_dd accordingly, similar for the below
ones.
> +
> + const _Decimal64 __builtin_dfp_quantize_64i (const int<5>, _Decimal64, \
> + const int<2>);
> + DFPQUAN_64i dfp_quan_idd {}
> +
> + const _Decimal128 __builtin_dfp_quantize_128 (_Decimal128, _Decimal128, \
> + const int<2>);
> + DFPQUAN_128 dfp_quan_td {}
> +
> + const _Decimal128 __builtin_dfp_quantize_128i (const int<5>, _Decimal128, \
> + const int<2>);
> + DFPQUAN_128i dfp_quan_itd {}
>
> [crypto]
> const vull __builtin_crypto_vcipher (vull, vull);
> diff --git a/gcc/config/rs6000/rs6000-overload.def
> b/gcc/config/rs6000/rs6000-overload.def
> index b83946f5ad8..3bb1bedd69d 100644
> --- a/gcc/config/rs6000/rs6000-overload.def
> +++ b/gcc/config/rs6000/rs6000-overload.def
> @@ -195,6 +195,18 @@
> unsigned long long __builtin_cmpb (unsigned long long, unsigned long long);
> CMPB
>
> +[DFPQUAN_64, dfp_quan_64, __builtin_dfp_quantize]
> + _Decimal64 __builtin_dfp_quantize (_Decimal64, _Decimal64, const int);
> + DFPQUAN_64
> + _Decimal64 __builtin_dfp_quantize (const int, _Decimal64, const int);
> + DFPQUAN_64i
> +
> +[DFPQUAN_128, dfp_quan_128, __builtin_dfpq_quantize]
> + _Decimal128 __builtin_dfpq_quantize (_Decimal128, _Decimal128, const int);
> + DFPQUAN_128
> + _Decimal128 __builtin_dfpq_quantize (const int, _Decimal128, const int);
> + DFPQUAN_128i
> +
> [VEC_ABS, vec_abs, __builtin_vec_abs]
> vsc __builtin_vec_abs (vsc);
> ABS_V16QI
> diff --git a/gcc/testsuite/gcc.target/powerpc/builtin-dfp-quantize-runnable.c
> b/gcc/testsuite/gcc.target/powerpc/builtin-dfp-quantize-runnable.c
> new file mode 100644
> index 00000000000..f4ba7236fe3
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/powerpc/builtin-dfp-quantize-runnable.c
Nit: Since there is PR93448, use its name as test case name?
Also add one line as PR marker in commit log.
> @@ -0,0 +1,198 @@
> +/* { dg-do run } */
> +/* { dg-require-effective-target dfp } */> +/* { dg-options "-O2
> -save-temps" } */
Since this is for run, I think what you want are:
/* { dg-require-effective-target dfp_hw } */
/* { dg-require-effective-target has_arch_pwr6 } */
/* { dg-options "-mhard-float -O2 -save-temps" } */
> +
> +
> +#define DEBUG 0
> +
> +#ifdef DEBUG
> +#include <stdio.h>
> +#endif
> +#include <float.h>
> +
> +void abort (void);
> +
> +int main()
> +{
> +#define IMM2 2
> +#define IMM3 3
> +#define IMM4 4
> +
> + _Decimal64 srcA_dfp64, srcB_dfp64;
> + _Decimal64 result_dfp64;
> + _Decimal64 expected_result_dfp64;
> + _Decimal128 srcA_dfp128, srcB_dfp128;
> + _Decimal128 result_dfp128;
> + _Decimal128 expected_result_dfp128;
> +
> + /* Third argument of quantize built-ins is the rounding mode value (RMC).
> +
> + RMC Rounding Mode
> + 00 Round toward 0
> + 01 Round to -infinity
> + 10 Round to nearest, ties toward 0
> + 11 Round according to DRN */
As ISA doc, the description should be:
Primary
RMC Rounding Mode
00 Round to nearest, ties to even
01 Round toward 0
10 Round to nearest, ties away from 0
11 Round according to DRN
BR,
Kewen
