[Piglit] [PATCH] CL: Fix check of ULP when probing float/double results
Jan Vesely
jan.vesely at rutgers.edu
Sun Jun 14 14:19:53 PDT 2015
On Sat, 2015-06-13 at 21:22 -0500, Aaron Watry wrote:
> Meh, this still feels broken. Give me a bit longer.
and it is :). I don't think this can work based on abs(expected - real),
since ULP depends on the magnitude of the numbers. This information is
lost after subtraction.
I had an idea some time back to implement this using nextafterf in both
directions and checking whether the result falls in that interval.
However, there is still a problem. Some of the expected values are
already rounded (I'm not sure what rounding mode is used by python by
default), but unless it always rounds in one direction, we'll still get
slight differences based on whether the actual value was rounded up or
down.
I have attached a small test program that shows the deficiencies of
fabsf based approaches.
regards,
Jan
>
> --Aaron
>
> On Sat, Jun 13, 2015 at 2:28 PM, Aaron Watry <awatry at gmail.com> wrote:
>
> > We need to actually check against the float value from the union,
> > instead of just doing (diff > ulp), which seems to cast the diff to
> > an int before checking against ulp.
> >
> > Signed-off-by: Aaron Watry <awatry at gmail.com>
> > CC: Tom Stellard <thomas.stellard at amd.com>
> > CC: Jan Vesely <jan.vesely at rutgers.edu>
> > ---
> > tests/util/piglit-util-cl.c | 28 ++++++++++++++--------------
> > 1 file changed, 14 insertions(+), 14 deletions(-)
> >
> > diff --git a/tests/util/piglit-util-cl.c b/tests/util/piglit-util-cl.c
> > index 47e0c7a..6cdd718 100644
> > --- a/tests/util/piglit-util-cl.c
> > +++ b/tests/util/piglit-util-cl.c
> > @@ -80,7 +80,7 @@ piglit_cl_probe_floating(float value, float expect,
> > uint32_t ulp)
> >
> > diff = fabsf(value - expect);
> >
> > - if(diff > ulp || isnan(value)) {
> > + if (diff > t.f || isnan(value)) {
> > printf("Expecting %f (0x%x) with tolerance %f (%u ulps),
> > but got %f (0x%x)\n",
> > e.f, e.u, t.f, t.u, v.f, v.u);
> > return false;
> > @@ -108,7 +108,7 @@ piglit_cl_probe_double(double value, double expect,
> > uint64_t ulp)
> >
> > diff = fabsl(value - expect);
> >
> > - if(diff > ulp || isnan(value)) {
> > + if (diff > t.f || isnan(value)) {
> > printf("Expecting %f (0x%lx) with tolerance %f (%lu ulps),
> > but got %f (0x%lx)\n",
> > e.f, e.u, t.f, t.u, v.f, v.u);
> > return false;
> > @@ -162,7 +162,7 @@ piglit_cl_get_platform_version(cl_platform_id platform)
> > int scanf_count;
> > int major;
> > int minor;
> > -
> > +
> > /*
> > * Returned format:
> > *
> > OpenCL<space><major_version.minor_version><space><platform-specific
> > information>
> > @@ -353,7 +353,7 @@ piglit_cl_get_info(void* fn_ptr, void* obj, cl_uint
> > param)
> >
> > if(errNo == CL_SUCCESS) {
> > param_ptr = calloc(param_size, sizeof(char));
> > -
> > +
> > /* retrieve param */
> > if(fn_ptr == clGetPlatformInfo) {
> > errNo = clGetPlatformInfo(*(cl_platform_id*)obj,
> > param,
> > @@ -463,7 +463,7 @@ piglit_cl_get_program_build_info(cl_program program,
> > cl_device_id device,
> > .program = program,
> > .device = device
> > };
> > -
> > +
> > return piglit_cl_get_info(clGetProgramBuildInfo, &args, param);
> > }
> >
> > @@ -479,7 +479,7 @@ piglit_cl_get_kernel_work_group_info(cl_kernel kernel,
> > cl_device_id device,
> > .kernel = kernel,
> > .device = device
> > };
> > -
> > +
> > return piglit_cl_get_info(clGetKernelWorkGroupInfo, &args, param);
> > }
> >
> > @@ -620,7 +620,7 @@ piglit_cl_get_device_ids(cl_platform_id platform_id,
> > cl_device_type device_type,
> > piglit_cl_get_error_name(errNo));
> > return 0;
> > }
> > -
> > +
> > /* get device list */
> > if(device_ids != NULL && num_device_ids > 0) {
> > *device_ids = malloc(num_device_ids *
> > sizeof(cl_device_id));
> > @@ -761,7 +761,7 @@
> > piglit_cl_build_program_with_source_extended(piglit_cl_context context,
> > piglit_cl_get_error_name(errNo));
> > return NULL;
> > }
> > -
> > +
> > errNo = clBuildProgram(program,
> > context->num_devices,
> > context->device_ids,
> > @@ -788,7 +788,7 @@
> > piglit_cl_build_program_with_source_extended(piglit_cl_context context,
> > char* log =
> > piglit_cl_get_program_build_info(program,
> >
> > context->device_ids[i],
> >
> > CL_PROGRAM_BUILD_LOG);
> > -
> > +
> > printf("Build log for device %s:\n -------- \n%s\n
> > -------- \n",
> > device_name,
> > log);
> > @@ -848,11 +848,11 @@
> > piglit_cl_build_program_with_binary_extended(piglit_cl_context context,
> > for(i = 0; i < context->num_devices; i++) {
> > char* device_name =
> > piglit_cl_get_device_info(context->device_ids[i],
> >
> > CL_DEVICE_NAME);
> > -
> > +
> > printf("Error for %s: %s\n",
> > device_name,
> > piglit_cl_get_error_name(binary_status[i]));
> > -
> > +
> > free(device_name);
> > }
> >
> > @@ -860,7 +860,7 @@
> > piglit_cl_build_program_with_binary_extended(piglit_cl_context context,
> > return NULL;
> > }
> > free(binary_status);
> > -
> > +
> > errNo = clBuildProgram(program,
> > context->num_devices,
> > context->device_ids,
> > @@ -884,11 +884,11 @@
> > piglit_cl_build_program_with_binary_extended(piglit_cl_context context,
> > char* log =
> > piglit_cl_get_program_build_info(program,
> >
> > context->device_ids[i],
> >
> > CL_PROGRAM_BUILD_LOG);
> > -
> > +
> > printf("Build log for device %s:\n -------- \n%s\n
> > -------- \n",
> > device_name,
> > log);
> > -
> > +
> > free(device_name);
> > free(log);
> > }
> > --
> > 2.1.4
> >
> >
--
Jan Vesely <jan.vesely at rutgers.edu>
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