Re: [Qemu-devel] [PATCH 0/2] target/arm: Implement ARMv8.5-FRINT

[Laurent Desnogues]

Hi Richard,

On Sat, Feb 23, 2019 at 2:23 AM Richard Henderson
<address@hidden> wrote:
>
> Based-on: the ARMv8.2-FHM patch set, although I don't know that
> this is an actual dependency; it's just the tree I started with.
>
> There is not yet support for this extension within FVP, so I've
> self-tested it against my own understanding of what is supposed
> to go on with the file below.

I ran some tests and found no issue.  Your understanding looks correct :-)

Tested-by: Laurent Desnogues <address@hidden>

Thanks,

Laurent


>
> r~
>
>
> Richard Henderson (2):
>   target/arm: Restructure handle_fp_1src_{single,double}
>   target/arm: Implement ARMv8.5-FRINT
>
>  target/arm/cpu.h           |   5 ++
>  target/arm/helper.h        |   5 ++
>  target/arm/cpu64.c         |   1 +
>  target/arm/translate-a64.c | 161 ++++++++++++++++++++++++++-----------
>  target/arm/vfp_helper.c    |  96 ++++++++++++++++++++++
>  5 files changed, 222 insertions(+), 46 deletions(-)
>
> --
>
> #include <stdio.h>
> #include <limits.h>
>
> asm(".arch armv8.5-a");
>
> static const float f32_i32_z[][2] = {
>     { 0, 0 },
>     { -0.0, -0.0 },
>     { 0.9, 0.0 },
>     { 1.0, 1.0 },
>     { 1.1, 1.0 },
>     { 1.9, 1.0 },
>     { 0x1.fffffep30, 0x1.fffffep30 },           /* 2^31 - epsilon */
>     { -0x1p31, -0x1.0p31 },                     /* -2^31 = INT32_MIN */
>     { 0x1.0p31, -0x1.0p31 },                    /* overflow */
>     { 0x1.0p32, -0x1.0p31 },                    /* overflow */
>     { -0x1.0p32, -0x1.0p31 },                   /* overflow */
>     { __builtin_inf(), -0x1.0p31 },             /* overflow */
> };
>
> static const double f64_i32_z[][2] = {
>     { 0, 0 },
>     { -0.0, -0.0 },
>     { 0.9, 0.0 },
>     { 1.0, 1.0 },
>     { 1.1, 1.0 },
>     { 1.9, 1.0 },
>     { 2147483647, 2147483647 },                 /* 2^31 - 1 = INT32_MAX */
>     { -0x1p31, -0x1.0p31 },                     /* -2^31 = INT32_MIN */
>     { 0x1.0p31, -0x1.0p31 },                    /* overflow */
>     { 0x1.0p32, -0x1.0p31 },                    /* overflow */
>     { -0x1.0p32, -0x1.0p31 },                   /* overflow */
>     { __builtin_inf(), -0x1.0p31 },             /* overflow */
> };
>
> static const float f32_i64_z[][2] = {
>     { 0, 0 },
>     { -0.0, -0.0 },
>     { 0.9, 0.0 },
>     { 1.0, 1.0 },
>     { 1.1, 1.0 },
>     { 1.9, 1.0 },
>     { 0x1.fffffep30, 0x1.fffffep30 },           /* 2^31 - epsilon */
>     { -0x1p31, -0x1.0p31 },                     /* -2^31 = INT32_MIN */
>     { 0x1.0p31, 0x1.0p31 },
>     { 0x1.0p32, 0x1.0p32 },
>     { -0x1.0p32, -0x1.0p32 },
>     { 0x1.0p62, 0x1.0p62 },
>     { 0x1.fffffep62, 0x1.fffffep62 },           /* 2^63 - epsilon */
>     { -0x1.0p63, -0x1.0p63 },                   /* -2^63 = INT64_MIN */
>     { 0x1.0p63, -0x1.0p63 },                    /* overflow */
>     { 0x1.0p64, -0x1.0p63 },                    /* overflow */
>     { -0x1.0p64, -0x1.0p63 },                   /* overflow */
>     { __builtin_inf(), -0x1.0p63 },             /* overflow */
> };
>
> static const double f64_i64_z[][2] = {
>     { 0, 0 },
>     { -0.0, -0.0 },
>     { 0.9, 0.0 },
>     { 1.0, 1.0 },
>     { 1.1, 1.0 },
>     { 1.9, 1.0 },
>     { 2147483647, 2147483647 },                 /* 2^31 - 1 = INT32_MAX */
>     { -0x1p31, -0x1.0p31 },                     /* -2^31 = INT32_MIN */
>     { 0x1.0p31, 0x1.0p31 },
>     { 0x1.0p32, 0x1.0p32 },
>     { -0x1.0p32, -0x1.0p32 },
>     { 0x1.0p62, 0x1.0p62 },
>     { 0x1.fffffffffffffp62, 0x1.fffffffffffffp62 }, /* 2^63 - epsilon */
>     { -0x1.0p63, -0x1.0p63 },                   /* -2^63 = INT64_MIN */
>     { 0x1.0p63, -0x1.0p63 },                    /* overflow */
>     { 0x1.0p64, -0x1.0p63 },                    /* overflow */
>     { -0x1.0p64, -0x1.0p63 },                   /* overflow */
>     { __builtin_inf(), -0x1.0p63 },             /* overflow */
> };
>
> int main()
> {
>     int i;
>
>     for (i = 0; i < sizeof(f32_i32_z)/sizeof(f32_i32_z[0]); i++) {
>         float x;
>         asm("frint32z %s0,%s1" : "=w"(x) : "w"(f32_i32_z[i][0]));
>         if (x != f32_i32_z[i][1]) {
>             printf("%-2d: frint(%a) -> %a != %a\n",
>                    i, f32_i32_z[i][0], x, f32_i32_z[i][1]);
>         }
>     }
>
>     for (i = 0; i < sizeof(f32_i64_z)/sizeof(f32_i64_z[0]); i++) {
>         float x;
>         asm("frint64z %s0,%s1" : "=w"(x) : "w"(f32_i64_z[i][0]));
>         if (x != f32_i64_z[i][1]) {
>             printf("%-2d: frint(%a) -> %a != %a\n",
>                    i, f32_i64_z[i][0], x, f32_i64_z[i][1]);
>         }
>     }
>
>     for (i = 0; i < sizeof(f64_i32_z)/sizeof(f64_i32_z[0]); i++) {
>         double x;
>         asm("frint32z %d0,%d1" : "=w"(x) : "w"(f64_i32_z[i][0]));
>         if (x != f64_i32_z[i][1]) {
>             printf("%-2d: frint(%a) -> %a != %a\n",
>                    i, f64_i32_z[i][0], x, f64_i32_z[i][1]);
>         }
>     }
>
>     for (i = 0; i < sizeof(f64_i64_z)/sizeof(f64_i64_z[0]); i++) {
>         double x;
>         asm("frint64z %d0,%d1" : "=w"(x) : "w"(f64_i64_z[i][0]));
>         if (x != f64_i64_z[i][1]) {
>             printf("%-2d: frint(%a) -> %a != %a\n",
>                    i, f64_i64_z[i][0], x, f64_i64_z[i][1]);
>         }
>     }
>
>     return 0;
> }
>